2597 Commits

Author SHA1 Message Date
Paolo Bonzini
86014c1e20 KVM generic changes for 6.11
- Enable halt poll shrinking by default, as Intel found it to be a clear win.
 
  - Setup empty IRQ routing when creating a VM to avoid having to synchronize
    SRCU when creating a split IRQCHIP on x86.
 
  - Rework the sched_in/out() paths to replace kvm_arch_sched_in() with a flag
    that arch code can use for hooking both sched_in() and sched_out().
 
  - Take the vCPU @id as an "unsigned long" instead of "u32" to avoid
    truncating a bogus value from userspace, e.g. to help userspace detect bugs.
 
  - Mark a vCPU as preempted if and only if it's scheduled out while in the
    KVM_RUN loop, e.g. to avoid marking it preempted and thus writing guest
    memory when retrieving guest state during live migration blackout.
 
  - A few minor cleanups
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Merge tag 'kvm-x86-generic-6.11' of https://github.com/kvm-x86/linux into HEAD

KVM generic changes for 6.11

 - Enable halt poll shrinking by default, as Intel found it to be a clear win.

 - Setup empty IRQ routing when creating a VM to avoid having to synchronize
   SRCU when creating a split IRQCHIP on x86.

 - Rework the sched_in/out() paths to replace kvm_arch_sched_in() with a flag
   that arch code can use for hooking both sched_in() and sched_out().

 - Take the vCPU @id as an "unsigned long" instead of "u32" to avoid
   truncating a bogus value from userspace, e.g. to help userspace detect bugs.

 - Mark a vCPU as preempted if and only if it's scheduled out while in the
   KVM_RUN loop, e.g. to avoid marking it preempted and thus writing guest
   memory when retrieving guest state during live migration blackout.

 - A few minor cleanups
2024-07-16 09:51:36 -04:00
David Matlack
a6816314af KVM: Introduce vcpu->wants_to_run
Introduce vcpu->wants_to_run to indicate when a vCPU is in its core run
loop, i.e. when the vCPU is running the KVM_RUN ioctl and immediate_exit
was not set.

Replace all references to vcpu->run->immediate_exit with
!vcpu->wants_to_run to avoid TOCTOU races with userspace. For example, a
malicious userspace could invoked KVM_RUN with immediate_exit=true and
then after KVM reads it to set wants_to_run=false, flip it to false.
This would result in the vCPU running in KVM_RUN with
wants_to_run=false. This wouldn't cause any real bugs today but is a
dangerous landmine.

Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://lore.kernel.org/r/20240503181734.1467938-2-dmatlack@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-06-18 09:20:01 -07:00
Michael Ellerman
a986fa57fd KVM: PPC: Book3S HV: Prevent UAF in kvm_spapr_tce_attach_iommu_group()
Al reported a possible use-after-free (UAF) in kvm_spapr_tce_attach_iommu_group().

It looks up `stt` from tablefd, but then continues to use it after doing
fdput() on the returned fd. After the fdput() the tablefd is free to be
closed by another thread. The close calls kvm_spapr_tce_release() and
then release_spapr_tce_table() (via call_rcu()) which frees `stt`.

Although there are calls to rcu_read_lock() in
kvm_spapr_tce_attach_iommu_group() they are not sufficient to prevent
the UAF, because `stt` is used outside the locked regions.

With an artifcial delay after the fdput() and a userspace program which
triggers the race, KASAN detects the UAF:

  BUG: KASAN: slab-use-after-free in kvm_spapr_tce_attach_iommu_group+0x298/0x720 [kvm]
  Read of size 4 at addr c000200027552c30 by task kvm-vfio/2505
  CPU: 54 PID: 2505 Comm: kvm-vfio Not tainted 6.10.0-rc3-next-20240612-dirty #1
  Hardware name: 8335-GTH POWER9 0x4e1202 opal:skiboot-v6.5.3-35-g1851b2a06 PowerNV
  Call Trace:
    dump_stack_lvl+0xb4/0x108 (unreliable)
    print_report+0x2b4/0x6ec
    kasan_report+0x118/0x2b0
    __asan_load4+0xb8/0xd0
    kvm_spapr_tce_attach_iommu_group+0x298/0x720 [kvm]
    kvm_vfio_set_attr+0x524/0xac0 [kvm]
    kvm_device_ioctl+0x144/0x240 [kvm]
    sys_ioctl+0x62c/0x1810
    system_call_exception+0x190/0x440
    system_call_vectored_common+0x15c/0x2ec
  ...
  Freed by task 0:
   ...
   kfree+0xec/0x3e0
   release_spapr_tce_table+0xd4/0x11c [kvm]
   rcu_core+0x568/0x16a0
   handle_softirqs+0x23c/0x920
   do_softirq_own_stack+0x6c/0x90
   do_softirq_own_stack+0x58/0x90
   __irq_exit_rcu+0x218/0x2d0
   irq_exit+0x30/0x80
   arch_local_irq_restore+0x128/0x230
   arch_local_irq_enable+0x1c/0x30
   cpuidle_enter_state+0x134/0x5cc
   cpuidle_enter+0x6c/0xb0
   call_cpuidle+0x7c/0x100
   do_idle+0x394/0x410
   cpu_startup_entry+0x60/0x70
   start_secondary+0x3fc/0x410
   start_secondary_prolog+0x10/0x14

Fix it by delaying the fdput() until `stt` is no longer in use, which
is effectively the entire function. To keep the patch minimal add a call
to fdput() at each of the existing return paths. Future work can convert
the function to goto or __cleanup style cleanup.

With the fix in place the test case no longer triggers the UAF.

Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Closes: https://lore.kernel.org/all/20240610024437.GA1464458@ZenIV/
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240614122910.3499489-1-mpe@ellerman.id.au
2024-06-16 10:20:11 +10:00
Linus Torvalds
ff2632d7d0 powerpc updates for 6.10
- Enable BPF Kernel Functions (kfuncs) in the powerpc BPF JIT.
 
  - Allow per-process DEXCR (Dynamic Execution Control Register) settings via
    prctl, notably NPHIE which controls hashst/hashchk for ROP protection.
 
  - Install powerpc selftests in sub-directories. Note this changes the way
    run_kselftest.sh needs to be invoked for powerpc selftests.
 
  - Change fadump (Firmware Assisted Dump) to better handle memory add/remove.
 
  - Add support for passing additional parameters to the fadump kernel.
 
  - Add support for updating the kdump image on CPU/memory add/remove events.
 
  - Other small features, cleanups and fixes.
 
 Thanks to: Andrew Donnellan, Andy Shevchenko, Aneesh Kumar K.V, Arnd Bergmann,
 Benjamin Gray, Bjorn Helgaas, Christian Zigotzky, Christophe Jaillet, Christophe
 Leroy, Colin Ian King, Cédric Le Goater, Dr. David Alan Gilbert, Erhard Furtner,
 Frank Li, GUO Zihua, Ganesh Goudar, Geoff Levand, Ghanshyam Agrawal, Greg Kurz,
 Hari Bathini, Joel Stanley, Justin Stitt, Kunwu Chan, Li Yang, Lidong Zhong,
 Madhavan Srinivasan, Mahesh Salgaonkar, Masahiro Yamada, Matthias Schiffer,
 Naresh Kamboju, Nathan Chancellor, Nathan Lynch, Naveen N Rao, Nicholas
 Miehlbradt, Ran Wang, Randy Dunlap, Ritesh Harjani, Sachin Sant, Shirisha Ganta,
 Shrikanth Hegde, Sourabh Jain, Stephen Rothwell, sundar, Thorsten Blum, Vaibhav
 Jain, Xiaowei Bao, Yang Li, Zhao Chenhui.
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Merge tag 'powerpc-6.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:

 - Enable BPF Kernel Functions (kfuncs) in the powerpc BPF JIT.

 - Allow per-process DEXCR (Dynamic Execution Control Register) settings
   via prctl, notably NPHIE which controls hashst/hashchk for ROP
   protection.

 - Install powerpc selftests in sub-directories. Note this changes the
   way run_kselftest.sh needs to be invoked for powerpc selftests.

 - Change fadump (Firmware Assisted Dump) to better handle memory
   add/remove.

 - Add support for passing additional parameters to the fadump kernel.

 - Add support for updating the kdump image on CPU/memory add/remove
   events.

 - Other small features, cleanups and fixes.

Thanks to Andrew Donnellan, Andy Shevchenko, Aneesh Kumar K.V, Arnd
Bergmann, Benjamin Gray, Bjorn Helgaas, Christian Zigotzky, Christophe
Jaillet, Christophe Leroy, Colin Ian King, Cédric Le Goater, Dr. David
Alan Gilbert, Erhard Furtner, Frank Li, GUO Zihua, Ganesh Goudar, Geoff
Levand, Ghanshyam Agrawal, Greg Kurz, Hari Bathini, Joel Stanley, Justin
Stitt, Kunwu Chan, Li Yang, Lidong Zhong, Madhavan Srinivasan, Mahesh
Salgaonkar, Masahiro Yamada, Matthias Schiffer, Naresh Kamboju, Nathan
Chancellor, Nathan Lynch, Naveen N Rao, Nicholas Miehlbradt, Ran Wang,
Randy Dunlap, Ritesh Harjani, Sachin Sant, Shirisha Ganta, Shrikanth
Hegde, Sourabh Jain, Stephen Rothwell, sundar, Thorsten Blum, Vaibhav
Jain, Xiaowei Bao, Yang Li, and Zhao Chenhui.

* tag 'powerpc-6.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (85 commits)
  powerpc/fadump: Fix section mismatch warning
  powerpc/85xx: fix compile error without CONFIG_CRASH_DUMP
  powerpc/fadump: update documentation about bootargs_append
  powerpc/fadump: pass additional parameters when fadump is active
  powerpc/fadump: setup additional parameters for dump capture kernel
  powerpc/pseries/fadump: add support for multiple boot memory regions
  selftests/powerpc/dexcr: Fix spelling mistake "predicition" -> "prediction"
  KVM: PPC: Book3S HV nestedv2: Fix an error handling path in gs_msg_ops_kvmhv_nestedv2_config_fill_info()
  KVM: PPC: Fix documentation for ppc mmu caps
  KVM: PPC: code cleanup for kvmppc_book3s_irqprio_deliver
  KVM: PPC: Book3S HV nestedv2: Cancel pending DEC exception
  powerpc/xmon: Check cpu id in commands "c#", "dp#" and "dx#"
  powerpc/code-patching: Use dedicated memory routines for patching
  powerpc/code-patching: Test patch_instructions() during boot
  powerpc64/kasan: Pass virtual addresses to kasan_init_phys_region()
  powerpc: rename SPRN_HID2 define to SPRN_HID2_750FX
  powerpc: Fix typos
  powerpc/eeh: Fix spelling of the word "auxillary" and update comment
  macintosh/ams: Fix unused variable warning
  powerpc/Makefile: Remove bits related to the previous use of -mcmodel=large
  ...
2024-05-17 09:05:46 -07:00
Linus Torvalds
f4b0c4b508 ARM:
* Move a lot of state that was previously stored on a per vcpu
   basis into a per-CPU area, because it is only pertinent to the
   host while the vcpu is loaded. This results in better state
   tracking, and a smaller vcpu structure.
 
 * Add full handling of the ERET/ERETAA/ERETAB instructions in
   nested virtualisation. The last two instructions also require
   emulating part of the pointer authentication extension.
   As a result, the trap handling of pointer authentication has
   been greatly simplified.
 
 * Turn the global (and not very scalable) LPI translation cache
   into a per-ITS, scalable cache, making non directly injected
   LPIs much cheaper to make visible to the vcpu.
 
 * A batch of pKVM patches, mostly fixes and cleanups, as the
   upstreaming process seems to be resuming. Fingers crossed!
 
 * Allocate PPIs and SGIs outside of the vcpu structure, allowing
   for smaller EL2 mapping and some flexibility in implementing
   more or less than 32 private IRQs.
 
 * Purge stale mpidr_data if a vcpu is created after the MPIDR
   map has been created.
 
 * Preserve vcpu-specific ID registers across a vcpu reset.
 
 * Various minor cleanups and improvements.
 
 LoongArch:
 
 * Add ParaVirt IPI support.
 
 * Add software breakpoint support.
 
 * Add mmio trace events support.
 
 RISC-V:
 
 * Support guest breakpoints using ebreak
 
 * Introduce per-VCPU mp_state_lock and reset_cntx_lock
 
 * Virtualize SBI PMU snapshot and counter overflow interrupts
 
 * New selftests for SBI PMU and Guest ebreak
 
 * Some preparatory work for both TDX and SNP page fault handling.
   This also cleans up the page fault path, so that the priorities
   of various kinds of fauls (private page, no memory, write
   to read-only slot, etc.) are easier to follow.
 
 x86:
 
 * Minimize amount of time that shadow PTEs remain in the special
   REMOVED_SPTE state.  This is a state where the mmu_lock is held for
   reading but concurrent accesses to the PTE have to spin; shortening
   its use allows other vCPUs to repopulate the zapped region while
   the zapper finishes tearing down the old, defunct page tables.
 
 * Advertise the max mappable GPA in the "guest MAXPHYADDR" CPUID field,
   which is defined by hardware but left for software use.  This lets KVM
   communicate its inability to map GPAs that set bits 51:48 on hosts
   without 5-level nested page tables.  Guest firmware is expected to
   use the information when mapping BARs; this avoids that they end up at
   a legal, but unmappable, GPA.
 
 * Fixed a bug where KVM would not reject accesses to MSR that aren't
   supposed to exist given the vCPU model and/or KVM configuration.
 
 * As usual, a bunch of code cleanups.
 
 x86 (AMD):
 
 * Implement a new and improved API to initialize SEV and SEV-ES VMs, which
   will also be extendable to SEV-SNP.  The new API specifies the desired
   encryption in KVM_CREATE_VM and then separately initializes the VM.
   The new API also allows customizing the desired set of VMSA features;
   the features affect the measurement of the VM's initial state, and
   therefore enabling them cannot be done tout court by the hypervisor.
 
   While at it, the new API includes two bugfixes that couldn't be
   applied to the old one without a flag day in userspace or without
   affecting the initial measurement.  When a SEV-ES VM is created with
   the new VM type, KVM_GET_REGS/KVM_SET_REGS and friends are
   rejected once the VMSA has been encrypted.  Also, the FPU and AVX
   state will be synchronized and encrypted too.
 
 * Support for GHCB version 2 as applicable to SEV-ES guests.  This, once
   more, is only accessible when using the new KVM_SEV_INIT2 flow for
   initialization of SEV-ES VMs.
 
 x86 (Intel):
 
 * An initial bunch of prerequisite patches for Intel TDX were merged.
   They generally don't do anything interesting.  The only somewhat user
   visible change is a new debugging mode that checks that KVM's MMU
   never triggers a #VE virtualization exception in the guest.
 
 * Clear vmcs.EXIT_QUALIFICATION when synthesizing an EPT Misconfig VM-Exit to
   L1, as per the SDM.
 
 Generic:
 
 * Use vfree() instead of kvfree() for allocations that always use vcalloc()
   or __vcalloc().
 
 * Remove .change_pte() MMU notifier - the changes to non-KVM code are
   small and Andrew Morton asked that I also take those through the KVM
   tree.  The callback was only ever implemented by KVM (which was also the
   original user of MMU notifiers) but it had been nonfunctional ever since
   calls to set_pte_at_notify were wrapped with invalidate_range_start
   and invalidate_range_end... in 2012.
 
 Selftests:
 
 * Enhance the demand paging test to allow for better reporting and stressing
   of UFFD performance.
 
 * Convert the steal time test to generate TAP-friendly output.
 
 * Fix a flaky false positive in the xen_shinfo_test due to comparing elapsed
   time across two different clock domains.
 
 * Skip the MONITOR/MWAIT test if the host doesn't actually support MWAIT.
 
 * Avoid unnecessary use of "sudo" in the NX hugepage test wrapper shell
   script, to play nice with running in a minimal userspace environment.
 
 * Allow skipping the RSEQ test's sanity check that the vCPU was able to
   complete a reasonable number of KVM_RUNs, as the assert can fail on a
   completely valid setup.  If the test is run on a large-ish system that is
   otherwise idle, and the test isn't affined to a low-ish number of CPUs, the
   vCPU task can be repeatedly migrated to CPUs that are in deep sleep states,
   which results in the vCPU having very little net runtime before the next
   migration due to high wakeup latencies.
 
 * Define _GNU_SOURCE for all selftests to fix a warning that was introduced by
   a change to kselftest_harness.h late in the 6.9 cycle, and because forcing
   every test to #define _GNU_SOURCE is painful.
 
 * Provide a global pseudo-RNG instance for all tests, so that library code can
   generate random, but determinstic numbers.
 
 * Use the global pRNG to randomly force emulation of select writes from guest
   code on x86, e.g. to help validate KVM's emulation of locked accesses.
 
 * Allocate and initialize x86's GDT, IDT, TSS, segments, and default exception
   handlers at VM creation, instead of forcing tests to manually trigger the
   related setup.
 
 Documentation:
 
 * Fix a goof in the KVM_CREATE_GUEST_MEMFD documentation.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "ARM:

   - Move a lot of state that was previously stored on a per vcpu basis
     into a per-CPU area, because it is only pertinent to the host while
     the vcpu is loaded. This results in better state tracking, and a
     smaller vcpu structure.

   - Add full handling of the ERET/ERETAA/ERETAB instructions in nested
     virtualisation. The last two instructions also require emulating
     part of the pointer authentication extension. As a result, the trap
     handling of pointer authentication has been greatly simplified.

   - Turn the global (and not very scalable) LPI translation cache into
     a per-ITS, scalable cache, making non directly injected LPIs much
     cheaper to make visible to the vcpu.

   - A batch of pKVM patches, mostly fixes and cleanups, as the
     upstreaming process seems to be resuming. Fingers crossed!

   - Allocate PPIs and SGIs outside of the vcpu structure, allowing for
     smaller EL2 mapping and some flexibility in implementing more or
     less than 32 private IRQs.

   - Purge stale mpidr_data if a vcpu is created after the MPIDR map has
     been created.

   - Preserve vcpu-specific ID registers across a vcpu reset.

   - Various minor cleanups and improvements.

  LoongArch:

   - Add ParaVirt IPI support

   - Add software breakpoint support

   - Add mmio trace events support

  RISC-V:

   - Support guest breakpoints using ebreak

   - Introduce per-VCPU mp_state_lock and reset_cntx_lock

   - Virtualize SBI PMU snapshot and counter overflow interrupts

   - New selftests for SBI PMU and Guest ebreak

   - Some preparatory work for both TDX and SNP page fault handling.

     This also cleans up the page fault path, so that the priorities of
     various kinds of fauls (private page, no memory, write to read-only
     slot, etc.) are easier to follow.

  x86:

   - Minimize amount of time that shadow PTEs remain in the special
     REMOVED_SPTE state.

     This is a state where the mmu_lock is held for reading but
     concurrent accesses to the PTE have to spin; shortening its use
     allows other vCPUs to repopulate the zapped region while the zapper
     finishes tearing down the old, defunct page tables.

   - Advertise the max mappable GPA in the "guest MAXPHYADDR" CPUID
     field, which is defined by hardware but left for software use.

     This lets KVM communicate its inability to map GPAs that set bits
     51:48 on hosts without 5-level nested page tables. Guest firmware
     is expected to use the information when mapping BARs; this avoids
     that they end up at a legal, but unmappable, GPA.

   - Fixed a bug where KVM would not reject accesses to MSR that aren't
     supposed to exist given the vCPU model and/or KVM configuration.

   - As usual, a bunch of code cleanups.

  x86 (AMD):

   - Implement a new and improved API to initialize SEV and SEV-ES VMs,
     which will also be extendable to SEV-SNP.

     The new API specifies the desired encryption in KVM_CREATE_VM and
     then separately initializes the VM. The new API also allows
     customizing the desired set of VMSA features; the features affect
     the measurement of the VM's initial state, and therefore enabling
     them cannot be done tout court by the hypervisor.

     While at it, the new API includes two bugfixes that couldn't be
     applied to the old one without a flag day in userspace or without
     affecting the initial measurement. When a SEV-ES VM is created with
     the new VM type, KVM_GET_REGS/KVM_SET_REGS and friends are rejected
     once the VMSA has been encrypted. Also, the FPU and AVX state will
     be synchronized and encrypted too.

   - Support for GHCB version 2 as applicable to SEV-ES guests.

     This, once more, is only accessible when using the new
     KVM_SEV_INIT2 flow for initialization of SEV-ES VMs.

  x86 (Intel):

   - An initial bunch of prerequisite patches for Intel TDX were merged.

     They generally don't do anything interesting. The only somewhat
     user visible change is a new debugging mode that checks that KVM's
     MMU never triggers a #VE virtualization exception in the guest.

   - Clear vmcs.EXIT_QUALIFICATION when synthesizing an EPT Misconfig
     VM-Exit to L1, as per the SDM.

  Generic:

   - Use vfree() instead of kvfree() for allocations that always use
     vcalloc() or __vcalloc().

   - Remove .change_pte() MMU notifier - the changes to non-KVM code are
     small and Andrew Morton asked that I also take those through the
     KVM tree.

     The callback was only ever implemented by KVM (which was also the
     original user of MMU notifiers) but it had been nonfunctional ever
     since calls to set_pte_at_notify were wrapped with
     invalidate_range_start and invalidate_range_end... in 2012.

  Selftests:

   - Enhance the demand paging test to allow for better reporting and
     stressing of UFFD performance.

   - Convert the steal time test to generate TAP-friendly output.

   - Fix a flaky false positive in the xen_shinfo_test due to comparing
     elapsed time across two different clock domains.

   - Skip the MONITOR/MWAIT test if the host doesn't actually support
     MWAIT.

   - Avoid unnecessary use of "sudo" in the NX hugepage test wrapper
     shell script, to play nice with running in a minimal userspace
     environment.

   - Allow skipping the RSEQ test's sanity check that the vCPU was able
     to complete a reasonable number of KVM_RUNs, as the assert can fail
     on a completely valid setup.

     If the test is run on a large-ish system that is otherwise idle,
     and the test isn't affined to a low-ish number of CPUs, the vCPU
     task can be repeatedly migrated to CPUs that are in deep sleep
     states, which results in the vCPU having very little net runtime
     before the next migration due to high wakeup latencies.

   - Define _GNU_SOURCE for all selftests to fix a warning that was
     introduced by a change to kselftest_harness.h late in the 6.9
     cycle, and because forcing every test to #define _GNU_SOURCE is
     painful.

   - Provide a global pseudo-RNG instance for all tests, so that library
     code can generate random, but determinstic numbers.

   - Use the global pRNG to randomly force emulation of select writes
     from guest code on x86, e.g. to help validate KVM's emulation of
     locked accesses.

   - Allocate and initialize x86's GDT, IDT, TSS, segments, and default
     exception handlers at VM creation, instead of forcing tests to
     manually trigger the related setup.

  Documentation:

   - Fix a goof in the KVM_CREATE_GUEST_MEMFD documentation"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (225 commits)
  selftests/kvm: remove dead file
  KVM: selftests: arm64: Test vCPU-scoped feature ID registers
  KVM: selftests: arm64: Test that feature ID regs survive a reset
  KVM: selftests: arm64: Store expected register value in set_id_regs
  KVM: selftests: arm64: Rename helper in set_id_regs to imply VM scope
  KVM: arm64: Only reset vCPU-scoped feature ID regs once
  KVM: arm64: Reset VM feature ID regs from kvm_reset_sys_regs()
  KVM: arm64: Rename is_id_reg() to imply VM scope
  KVM: arm64: Destroy mpidr_data for 'late' vCPU creation
  KVM: arm64: Use hVHE in pKVM by default on CPUs with VHE support
  KVM: arm64: Fix hvhe/nvhe early alias parsing
  KVM: SEV: Allow per-guest configuration of GHCB protocol version
  KVM: SEV: Add GHCB handling for termination requests
  KVM: SEV: Add GHCB handling for Hypervisor Feature Support requests
  KVM: SEV: Add support to handle AP reset MSR protocol
  KVM: x86: Explicitly zero kvm_caps during vendor module load
  KVM: x86: Fully re-initialize supported_mce_cap on vendor module load
  KVM: x86: Fully re-initialize supported_vm_types on vendor module load
  KVM: x86/mmu: Sanity check that __kvm_faultin_pfn() doesn't create noslot pfns
  KVM: x86/mmu: Initialize kvm_page_fault's pfn and hva to error values
  ...
2024-05-15 14:46:43 -07:00
Michael Ellerman
6d4e52f899 Merge branch 'topic/ppc-kvm' into next
Merge our KVM topic branch.
2024-05-13 23:08:32 +10:00
Christophe JAILLET
b52e8cd3f8 KVM: PPC: Book3S HV nestedv2: Fix an error handling path in gs_msg_ops_kvmhv_nestedv2_config_fill_info()
The return value of kvmppc_gse_put_buff_info() is not assigned to 'rc' and
'rc' is uninitialized at this point.
So the error handling can not work.

Assign the expected value to 'rc' to fix the issue.

Fixes: 19d31c5f1157 ("KVM: PPC: Add support for nestedv2 guests")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/a7ed4cc12e0a0bbd97fac44fe6c222d1c393ec95.1706441651.git.christophe.jaillet@wanadoo.fr
2024-05-08 01:28:00 +10:00
Kunwu Chan
a9c08bcd31 KVM: PPC: code cleanup for kvmppc_book3s_irqprio_deliver
This part was commented from commit 2f4cf5e42d13 ("Add book3s.c")
in about 14 years before.
If there are no plans to enable this part code in the future,
we can remove this dead code.

Signed-off-by: Kunwu Chan <chentao@kylinos.cn>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240125083348.533883-1-chentao@kylinos.cn
2024-05-08 01:27:59 +10:00
Vaibhav Jain
7be6ce7043 KVM: PPC: Book3S HV nestedv2: Cancel pending DEC exception
This reverts commit 180c6b072bf3 ("KVM: PPC: Book3S HV nestedv2: Do not
cancel pending decrementer exception") [1] which prevented canceling a
pending HDEC exception for nestedv2 KVM guests. It was done to avoid
overhead of a H_GUEST_GET_STATE hcall to read the 'DEC expiry TB' register
which was higher compared to handling extra decrementer exceptions.

However recent benchmarks indicate that overhead of not handling 'DECR'
expiry for Nested KVM Guest(L2) is higher and results in much larger exits
to Pseries Host(L1) as indicated by the Unixbench-arithoh bench[2]

Metric	    	      | Current upstream    | Revert [1]  | Difference %
========================================================================
arithoh-count (10)    |	3244831634	    | 3403089673  | +04.88%
kvm_hv:kvm_guest_exit |	513558		    | 152441	  | -70.32%
probe:kvmppc_gsb_recv |	28060		    | 28110	  | +00.18%

N=1

As indicated by the data above that reverting [1] results in substantial
reduction in number of L2->L1 exits with only slight increase in number of
H_GUEST_GET_STATE hcalls to read the value of 'DEC expiry TB'. This results
in an overall ~4% improvement of arithoh[2] throughput.

[1] commit 180c6b072bf3 ("KVM: PPC: Book3S HV nestedv2: Do not cancel pending decrementer exception")
[2] https://github.com/kdlucas/byte-unixbench/

Fixes: 180c6b072bf3 ("KVM: PPC: Book3S HV nestedv2: Do not cancel pending decrementer exception")
Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240415035731.103097-1-vaibhav@linux.ibm.com
2024-05-08 01:27:59 +10:00
Matthias Schiffer
ad679719d7 powerpc: rename SPRN_HID2 define to SPRN_HID2_750FX
This register number is hardware-specific, rename it for clarity.

FIXME comments are added in a few places where it seems like the wrong
register is used. As I can't test this, only the rename is done with no
functional change.

Signed-off-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240124105031.45734-1-matthias.schiffer@ew.tq-group.com
2024-05-08 00:25:00 +10:00
Bjorn Helgaas
0ddbbb8960 powerpc: Fix typos
Fix typos, most reported by "codespell arch/powerpc".  Only touches
comments, no code changes.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240103231605.1801364-8-helgaas@kernel.org
2024-05-08 00:21:30 +10:00
Bitao Hu
86d2a2f51f genirq: Convert kstat_irqs to a struct
The irq_desc::kstat_irqs member is a per-CPU variable of type int, which is
only capable of counting. A snapshot mechanism for interrupt statistics
will be added soon, which requires an additional variable to store the
snapshot.

To facilitate expansion, convert kstat_irqs here to a struct containing
only the count.

Originally-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Bitao Hu <yaoma@linux.alibaba.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20240411074134.30922-2-yaoma@linux.alibaba.com
2024-04-12 17:08:05 +02:00
Paolo Bonzini
f3b65bbaed KVM: delete .change_pte MMU notifier callback
The .change_pte() MMU notifier callback was intended as an
optimization. The original point of it was that KSM could tell KVM to flip
its secondary PTE to a new location without having to first zap it. At
the time there was also an .invalidate_page() callback; both of them were
*not* bracketed by calls to mmu_notifier_invalidate_range_{start,end}(),
and .invalidate_page() also doubled as a fallback implementation of
.change_pte().

Later on, however, both callbacks were changed to occur within an
invalidate_range_start/end() block.

In the case of .change_pte(), commit 6bdb913f0a70 ("mm: wrap calls to
set_pte_at_notify with invalidate_range_start and invalidate_range_end",
2012-10-09) did so to remove the fallback from .invalidate_page() to
.change_pte() and allow sleepable .invalidate_page() hooks.

This however made KVM's usage of the .change_pte() callback completely
moot, because KVM unmaps the sPTEs during .invalidate_range_start()
and therefore .change_pte() has no hope of finding a sPTE to change.
Drop the generic KVM code that dispatches to kvm_set_spte_gfn(), as
well as all the architecture specific implementations.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Anup Patel <anup@brainfault.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Reviewed-by: Bibo Mao <maobibo@loongson.cn>
Message-ID: <20240405115815.3226315-2-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-04-11 13:18:27 -04:00
Linus Torvalds
66a27abac3 powerpc updates for 6.9
- Add AT_HWCAP3 and AT_HWCAP4 aux vector entries for future use by glibc.
 
  - Add support for recognising the Power11 architected and raw PVRs.
 
  - Add support for nr_cpus=n on the command line where the boot CPU is >= n.
 
  - Add ppcxx_allmodconfig targets for all 32-bit sub-arches.
 
  - Other small features, cleanups and fixes.
 
 Thanks to: Akanksha J N, Brian King, Christophe Leroy, Dawei Li, Geoff Levand,
 Greg Kroah-Hartman, Jan-Benedict Glaw, Kajol Jain, Kunwu Chan, Li zeming,
 Madhavan Srinivasan, Masahiro Yamada, Nathan Chancellor, Nicholas Piggin, Peter
 Bergner, Qiheng Lin, Randy Dunlap, Ricardo B. Marliere, Rob Herring, Sathvika
 Vasireddy, Shrikanth Hegde, Uwe Kleine-König, Vaibhav Jain, Wen Xiong.
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Merge tag 'powerpc-6.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:

 - Add AT_HWCAP3 and AT_HWCAP4 aux vector entries for future use
   by glibc

 - Add support for recognising the Power11 architected and raw PVRs

 - Add support for nr_cpus=n on the command line where the
   boot CPU is >= n

 - Add ppcxx_allmodconfig targets for all 32-bit sub-arches

 - Other small features, cleanups and fixes

Thanks to Akanksha J N, Brian King, Christophe Leroy, Dawei Li, Geoff
Levand, Greg Kroah-Hartman, Jan-Benedict Glaw, Kajol Jain, Kunwu Chan,
Li zeming, Madhavan Srinivasan, Masahiro Yamada, Nathan Chancellor,
Nicholas Piggin, Peter Bergner, Qiheng Lin, Randy Dunlap, Ricardo B.
Marliere, Rob Herring, Sathvika Vasireddy, Shrikanth Hegde, Uwe
Kleine-König, Vaibhav Jain, and Wen Xiong.

* tag 'powerpc-6.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (71 commits)
  powerpc/macio: Make remove callback of macio driver void returned
  powerpc/83xx: Fix build failure with FPU=n
  powerpc/64s: Fix get_hugepd_cache_index() build failure
  powerpc/4xx: Fix warp_gpio_leds build failure
  powerpc/amigaone: Make several functions static
  powerpc/embedded6xx: Fix no previous prototype for avr_uart_send() etc.
  macintosh/adb: make adb_dev_class constant
  powerpc: xor_vmx: Add '-mhard-float' to CFLAGS
  powerpc/fsl: Fix mfpmr() asm constraint error
  powerpc: Remove cpu-as-y completely
  powerpc/fsl: Modernise mt/mfpmr
  powerpc/fsl: Fix mfpmr build errors with newer binutils
  powerpc/64s: Use .machine power4 around dcbt
  powerpc/64s: Move dcbt/dcbtst sequence into a macro
  powerpc/mm: Code cleanup for __hash_page_thp
  powerpc/hv-gpci: Fix the H_GET_PERF_COUNTER_INFO hcall return value checks
  powerpc/irq: Allow softirq to hardirq stack transition
  powerpc: Stop using of_root
  powerpc/machdep: Define 'compatibles' property in ppc_md and use it
  of: Reimplement of_machine_is_compatible() using of_machine_compatible_match()
  ...
2024-03-15 17:53:48 -07:00
Linus Torvalds
4f712ee0cb S390:
* Changes to FPU handling came in via the main s390 pull request
 
 * Only deliver to the guest the SCLP events that userspace has
   requested.
 
 * More virtual vs physical address fixes (only a cleanup since
   virtual and physical address spaces are currently the same).
 
 * Fix selftests undefined behavior.
 
 x86:
 
 * Fix a restriction that the guest can't program a PMU event whose
   encoding matches an architectural event that isn't included in the
   guest CPUID.  The enumeration of an architectural event only says
   that if a CPU supports an architectural event, then the event can be
   programmed *using the architectural encoding*.  The enumeration does
   NOT say anything about the encoding when the CPU doesn't report support
   the event *in general*.  It might support it, and it might support it
   using the same encoding that made it into the architectural PMU spec.
 
 * Fix a variety of bugs in KVM's emulation of RDPMC (more details on
   individual commits) and add a selftest to verify KVM correctly emulates
   RDMPC, counter availability, and a variety of other PMC-related
   behaviors that depend on guest CPUID and therefore are easier to
   validate with selftests than with custom guests (aka kvm-unit-tests).
 
 * Zero out PMU state on AMD if the virtual PMU is disabled, it does not
   cause any bug but it wastes time in various cases where KVM would check
   if a PMC event needs to be synthesized.
 
 * Optimize triggering of emulated events, with a nice ~10% performance
   improvement in VM-Exit microbenchmarks when a vPMU is exposed to the
   guest.
 
 * Tighten the check for "PMI in guest" to reduce false positives if an NMI
   arrives in the host while KVM is handling an IRQ VM-Exit.
 
 * Fix a bug where KVM would report stale/bogus exit qualification information
   when exiting to userspace with an internal error exit code.
 
 * Add a VMX flag in /proc/cpuinfo to report 5-level EPT support.
 
 * Rework TDP MMU root unload, free, and alloc to run with mmu_lock held for
   read, e.g. to avoid serializing vCPUs when userspace deletes a memslot.
 
 * Tear down TDP MMU page tables at 4KiB granularity (used to be 1GiB).  KVM
   doesn't support yielding in the middle of processing a zap, and 1GiB
   granularity resulted in multi-millisecond lags that are quite impolite
   for CONFIG_PREEMPT kernels.
 
 * Allocate write-tracking metadata on-demand to avoid the memory overhead when
   a kernel is built with i915 virtualization support but the workloads use
   neither shadow paging nor i915 virtualization.
 
 * Explicitly initialize a variety of on-stack variables in the emulator that
   triggered KMSAN false positives.
 
 * Fix the debugregs ABI for 32-bit KVM.
 
 * Rework the "force immediate exit" code so that vendor code ultimately decides
   how and when to force the exit, which allowed some optimization for both
   Intel and AMD.
 
 * Fix a long-standing bug where kvm_has_noapic_vcpu could be left elevated if
   vCPU creation ultimately failed, causing extra unnecessary work.
 
 * Cleanup the logic for checking if the currently loaded vCPU is in-kernel.
 
 * Harden against underflowing the active mmu_notifier invalidation
   count, so that "bad" invalidations (usually due to bugs elsehwere in the
   kernel) are detected earlier and are less likely to hang the kernel.
 
 x86 Xen emulation:
 
 * Overlay pages can now be cached based on host virtual address,
   instead of guest physical addresses.  This removes the need to
   reconfigure and invalidate the cache if the guest changes the
   gpa but the underlying host virtual address remains the same.
 
 * When possible, use a single host TSC value when computing the deadline for
   Xen timers in order to improve the accuracy of the timer emulation.
 
 * Inject pending upcall events when the vCPU software-enables its APIC to fix
   a bug where an upcall can be lost (and to follow Xen's behavior).
 
 * Fall back to the slow path instead of warning if "fast" IRQ delivery of Xen
   events fails, e.g. if the guest has aliased xAPIC IDs.
 
 RISC-V:
 
 * Support exception and interrupt handling in selftests
 
 * New self test for RISC-V architectural timer (Sstc extension)
 
 * New extension support (Ztso, Zacas)
 
 * Support userspace emulation of random number seed CSRs.
 
 ARM:
 
 * Infrastructure for building KVM's trap configuration based on the
   architectural features (or lack thereof) advertised in the VM's ID
   registers
 
 * Support for mapping vfio-pci BARs as Normal-NC (vaguely similar to
   x86's WC) at stage-2, improving the performance of interacting with
   assigned devices that can tolerate it
 
 * Conversion of KVM's representation of LPIs to an xarray, utilized to
   address serialization some of the serialization on the LPI injection
   path
 
 * Support for _architectural_ VHE-only systems, advertised through the
   absence of FEAT_E2H0 in the CPU's ID register
 
 * Miscellaneous cleanups, fixes, and spelling corrections to KVM and
   selftests
 
 LoongArch:
 
 * Set reserved bits as zero in CPUCFG.
 
 * Start SW timer only when vcpu is blocking.
 
 * Do not restart SW timer when it is expired.
 
 * Remove unnecessary CSR register saving during enter guest.
 
 * Misc cleanups and fixes as usual.
 
 Generic:
 
 * cleanup Kconfig by removing CONFIG_HAVE_KVM, which was basically always
   true on all architectures except MIPS (where Kconfig determines the
   available depending on CPU capabilities).  It is replaced either by
   an architecture-dependent symbol for MIPS, and IS_ENABLED(CONFIG_KVM)
   everywhere else.
 
 * Factor common "select" statements in common code instead of requiring
   each architecture to specify it
 
 * Remove thoroughly obsolete APIs from the uapi headers.
 
 * Move architecture-dependent stuff to uapi/asm/kvm.h
 
 * Always flush the async page fault workqueue when a work item is being
   removed, especially during vCPU destruction, to ensure that there are no
   workers running in KVM code when all references to KVM-the-module are gone,
   i.e. to prevent a very unlikely use-after-free if kvm.ko is unloaded.
 
 * Grab a reference to the VM's mm_struct in the async #PF worker itself instead
   of gifting the worker a reference, so that there's no need to remember
   to *conditionally* clean up after the worker.
 
 Selftests:
 
 * Reduce boilerplate especially when utilize selftest TAP infrastructure.
 
 * Add basic smoke tests for SEV and SEV-ES, along with a pile of library
   support for handling private/encrypted/protected memory.
 
 * Fix benign bugs where tests neglect to close() guest_memfd files.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm updates from Paolo Bonzini:
 "S390:

   - Changes to FPU handling came in via the main s390 pull request

   - Only deliver to the guest the SCLP events that userspace has
     requested

   - More virtual vs physical address fixes (only a cleanup since
     virtual and physical address spaces are currently the same)

   - Fix selftests undefined behavior

  x86:

   - Fix a restriction that the guest can't program a PMU event whose
     encoding matches an architectural event that isn't included in the
     guest CPUID. The enumeration of an architectural event only says
     that if a CPU supports an architectural event, then the event can
     be programmed *using the architectural encoding*. The enumeration
     does NOT say anything about the encoding when the CPU doesn't
     report support the event *in general*. It might support it, and it
     might support it using the same encoding that made it into the
     architectural PMU spec

   - Fix a variety of bugs in KVM's emulation of RDPMC (more details on
     individual commits) and add a selftest to verify KVM correctly
     emulates RDMPC, counter availability, and a variety of other
     PMC-related behaviors that depend on guest CPUID and therefore are
     easier to validate with selftests than with custom guests (aka
     kvm-unit-tests)

   - Zero out PMU state on AMD if the virtual PMU is disabled, it does
     not cause any bug but it wastes time in various cases where KVM
     would check if a PMC event needs to be synthesized

   - Optimize triggering of emulated events, with a nice ~10%
     performance improvement in VM-Exit microbenchmarks when a vPMU is
     exposed to the guest

   - Tighten the check for "PMI in guest" to reduce false positives if
     an NMI arrives in the host while KVM is handling an IRQ VM-Exit

   - Fix a bug where KVM would report stale/bogus exit qualification
     information when exiting to userspace with an internal error exit
     code

   - Add a VMX flag in /proc/cpuinfo to report 5-level EPT support

   - Rework TDP MMU root unload, free, and alloc to run with mmu_lock
     held for read, e.g. to avoid serializing vCPUs when userspace
     deletes a memslot

   - Tear down TDP MMU page tables at 4KiB granularity (used to be
     1GiB). KVM doesn't support yielding in the middle of processing a
     zap, and 1GiB granularity resulted in multi-millisecond lags that
     are quite impolite for CONFIG_PREEMPT kernels

   - Allocate write-tracking metadata on-demand to avoid the memory
     overhead when a kernel is built with i915 virtualization support
     but the workloads use neither shadow paging nor i915 virtualization

   - Explicitly initialize a variety of on-stack variables in the
     emulator that triggered KMSAN false positives

   - Fix the debugregs ABI for 32-bit KVM

   - Rework the "force immediate exit" code so that vendor code
     ultimately decides how and when to force the exit, which allowed
     some optimization for both Intel and AMD

   - Fix a long-standing bug where kvm_has_noapic_vcpu could be left
     elevated if vCPU creation ultimately failed, causing extra
     unnecessary work

   - Cleanup the logic for checking if the currently loaded vCPU is
     in-kernel

   - Harden against underflowing the active mmu_notifier invalidation
     count, so that "bad" invalidations (usually due to bugs elsehwere
     in the kernel) are detected earlier and are less likely to hang the
     kernel

  x86 Xen emulation:

   - Overlay pages can now be cached based on host virtual address,
     instead of guest physical addresses. This removes the need to
     reconfigure and invalidate the cache if the guest changes the gpa
     but the underlying host virtual address remains the same

   - When possible, use a single host TSC value when computing the
     deadline for Xen timers in order to improve the accuracy of the
     timer emulation

   - Inject pending upcall events when the vCPU software-enables its
     APIC to fix a bug where an upcall can be lost (and to follow Xen's
     behavior)

   - Fall back to the slow path instead of warning if "fast" IRQ
     delivery of Xen events fails, e.g. if the guest has aliased xAPIC
     IDs

  RISC-V:

   - Support exception and interrupt handling in selftests

   - New self test for RISC-V architectural timer (Sstc extension)

   - New extension support (Ztso, Zacas)

   - Support userspace emulation of random number seed CSRs

  ARM:

   - Infrastructure for building KVM's trap configuration based on the
     architectural features (or lack thereof) advertised in the VM's ID
     registers

   - Support for mapping vfio-pci BARs as Normal-NC (vaguely similar to
     x86's WC) at stage-2, improving the performance of interacting with
     assigned devices that can tolerate it

   - Conversion of KVM's representation of LPIs to an xarray, utilized
     to address serialization some of the serialization on the LPI
     injection path

   - Support for _architectural_ VHE-only systems, advertised through
     the absence of FEAT_E2H0 in the CPU's ID register

   - Miscellaneous cleanups, fixes, and spelling corrections to KVM and
     selftests

  LoongArch:

   - Set reserved bits as zero in CPUCFG

   - Start SW timer only when vcpu is blocking

   - Do not restart SW timer when it is expired

   - Remove unnecessary CSR register saving during enter guest

   - Misc cleanups and fixes as usual

  Generic:

   - Clean up Kconfig by removing CONFIG_HAVE_KVM, which was basically
     always true on all architectures except MIPS (where Kconfig
     determines the available depending on CPU capabilities). It is
     replaced either by an architecture-dependent symbol for MIPS, and
     IS_ENABLED(CONFIG_KVM) everywhere else

   - Factor common "select" statements in common code instead of
     requiring each architecture to specify it

   - Remove thoroughly obsolete APIs from the uapi headers

   - Move architecture-dependent stuff to uapi/asm/kvm.h

   - Always flush the async page fault workqueue when a work item is
     being removed, especially during vCPU destruction, to ensure that
     there are no workers running in KVM code when all references to
     KVM-the-module are gone, i.e. to prevent a very unlikely
     use-after-free if kvm.ko is unloaded

   - Grab a reference to the VM's mm_struct in the async #PF worker
     itself instead of gifting the worker a reference, so that there's
     no need to remember to *conditionally* clean up after the worker

  Selftests:

   - Reduce boilerplate especially when utilize selftest TAP
     infrastructure

   - Add basic smoke tests for SEV and SEV-ES, along with a pile of
     library support for handling private/encrypted/protected memory

   - Fix benign bugs where tests neglect to close() guest_memfd files"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (246 commits)
  selftests: kvm: remove meaningless assignments in Makefiles
  KVM: riscv: selftests: Add Zacas extension to get-reg-list test
  RISC-V: KVM: Allow Zacas extension for Guest/VM
  KVM: riscv: selftests: Add Ztso extension to get-reg-list test
  RISC-V: KVM: Allow Ztso extension for Guest/VM
  RISC-V: KVM: Forward SEED CSR access to user space
  KVM: riscv: selftests: Add sstc timer test
  KVM: riscv: selftests: Change vcpu_has_ext to a common function
  KVM: riscv: selftests: Add guest helper to get vcpu id
  KVM: riscv: selftests: Add exception handling support
  LoongArch: KVM: Remove unnecessary CSR register saving during enter guest
  LoongArch: KVM: Do not restart SW timer when it is expired
  LoongArch: KVM: Start SW timer only when vcpu is blocking
  LoongArch: KVM: Set reserved bits as zero in CPUCFG
  KVM: selftests: Explicitly close guest_memfd files in some gmem tests
  KVM: x86/xen: fix recursive deadlock in timer injection
  KVM: pfncache: simplify locking and make more self-contained
  KVM: x86/xen: remove WARN_ON_ONCE() with false positives in evtchn delivery
  KVM: x86/xen: inject vCPU upcall vector when local APIC is enabled
  KVM: x86/xen: improve accuracy of Xen timers
  ...
2024-03-15 13:03:13 -07:00
Linus Torvalds
e5eb28f6d1 - Kuan-Wei Chiu has developed the well-named series "lib min_heap: Min
heap optimizations".
 
 - Kuan-Wei Chiu has also sped up the library sorting code in the series
   "lib/sort: Optimize the number of swaps and comparisons".
 
 - Alexey Gladkov has added the ability for code running within an IPC
   namespace to alter its IPC and MQ limits.  The series is "Allow to
   change ipc/mq sysctls inside ipc namespace".
 
 - Geert Uytterhoeven has contributed some dhrystone maintenance work in
   the series "lib: dhry: miscellaneous cleanups".
 
 - Ryusuke Konishi continues nilfs2 maintenance work in the series
 
 	"nilfs2: eliminate kmap and kmap_atomic calls"
 	"nilfs2: fix kernel bug at submit_bh_wbc()"
 
 - Nathan Chancellor has updated our build tools requirements in the
   series "Bump the minimum supported version of LLVM to 13.0.1".
 
 - Muhammad Usama Anjum continues with the selftests maintenance work in
   the series "selftests/mm: Improve run_vmtests.sh".
 
 - Oleg Nesterov has done some maintenance work against the signal code
   in the series "get_signal: minor cleanups and fix".
 
 Plus the usual shower of singleton patches in various parts of the tree.
 Please see the individual changelogs for details.
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Merge tag 'mm-nonmm-stable-2024-03-14-09-36' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull non-MM updates from Andrew Morton:

 - Kuan-Wei Chiu has developed the well-named series "lib min_heap: Min
   heap optimizations".

 - Kuan-Wei Chiu has also sped up the library sorting code in the series
   "lib/sort: Optimize the number of swaps and comparisons".

 - Alexey Gladkov has added the ability for code running within an IPC
   namespace to alter its IPC and MQ limits. The series is "Allow to
   change ipc/mq sysctls inside ipc namespace".

 - Geert Uytterhoeven has contributed some dhrystone maintenance work in
   the series "lib: dhry: miscellaneous cleanups".

 - Ryusuke Konishi continues nilfs2 maintenance work in the series

	"nilfs2: eliminate kmap and kmap_atomic calls"
	"nilfs2: fix kernel bug at submit_bh_wbc()"

 - Nathan Chancellor has updated our build tools requirements in the
   series "Bump the minimum supported version of LLVM to 13.0.1".

 - Muhammad Usama Anjum continues with the selftests maintenance work in
   the series "selftests/mm: Improve run_vmtests.sh".

 - Oleg Nesterov has done some maintenance work against the signal code
   in the series "get_signal: minor cleanups and fix".

Plus the usual shower of singleton patches in various parts of the tree.
Please see the individual changelogs for details.

* tag 'mm-nonmm-stable-2024-03-14-09-36' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (77 commits)
  nilfs2: prevent kernel bug at submit_bh_wbc()
  nilfs2: fix failure to detect DAT corruption in btree and direct mappings
  ocfs2: enable ocfs2_listxattr for special files
  ocfs2: remove SLAB_MEM_SPREAD flag usage
  assoc_array: fix the return value in assoc_array_insert_mid_shortcut()
  buildid: use kmap_local_page()
  watchdog/core: remove sysctl handlers from public header
  nilfs2: use div64_ul() instead of do_div()
  mul_u64_u64_div_u64: increase precision by conditionally swapping a and b
  kexec: copy only happens before uchunk goes to zero
  get_signal: don't initialize ksig->info if SIGNAL_GROUP_EXIT/group_exec_task
  get_signal: hide_si_addr_tag_bits: fix the usage of uninitialized ksig
  get_signal: don't abuse ksig->info.si_signo and ksig->sig
  const_structs.checkpatch: add device_type
  Normalise "name (ad@dr)" MODULE_AUTHORs to "name <ad@dr>"
  dyndbg: replace kstrdup() + strchr() with kstrdup_and_replace()
  list: leverage list_is_head() for list_entry_is_head()
  nilfs2: MAINTAINERS: drop unreachable project mirror site
  smp: make __smp_processor_id() 0-argument macro
  fat: fix uninitialized field in nostale filehandles
  ...
2024-03-14 18:03:09 -07:00
Linus Torvalds
902861e34c - Sumanth Korikkar has taught s390 to allocate hotplug-time page frames
from hotplugged memory rather than only from main memory.  Series
   "implement "memmap on memory" feature on s390".
 
 - More folio conversions from Matthew Wilcox in the series
 
 	"Convert memcontrol charge moving to use folios"
 	"mm: convert mm counter to take a folio"
 
 - Chengming Zhou has optimized zswap's rbtree locking, providing
   significant reductions in system time and modest but measurable
   reductions in overall runtimes.  The series is "mm/zswap: optimize the
   scalability of zswap rb-tree".
 
 - Chengming Zhou has also provided the series "mm/zswap: optimize zswap
   lru list" which provides measurable runtime benefits in some
   swap-intensive situations.
 
 - And Chengming Zhou further optimizes zswap in the series "mm/zswap:
   optimize for dynamic zswap_pools".  Measured improvements are modest.
 
 - zswap cleanups and simplifications from Yosry Ahmed in the series "mm:
   zswap: simplify zswap_swapoff()".
 
 - In the series "Add DAX ABI for memmap_on_memory", Vishal Verma has
   contributed several DAX cleanups as well as adding a sysfs tunable to
   control the memmap_on_memory setting when the dax device is hotplugged
   as system memory.
 
 - Johannes Weiner has added the large series "mm: zswap: cleanups",
   which does that.
 
 - More DAMON work from SeongJae Park in the series
 
 	"mm/damon: make DAMON debugfs interface deprecation unignorable"
 	"selftests/damon: add more tests for core functionalities and corner cases"
 	"Docs/mm/damon: misc readability improvements"
 	"mm/damon: let DAMOS feeds and tame/auto-tune itself"
 
 - In the series "mm/mempolicy: weighted interleave mempolicy and sysfs
   extension" Rakie Kim has developed a new mempolicy interleaving policy
   wherein we allocate memory across nodes in a weighted fashion rather
   than uniformly.  This is beneficial in heterogeneous memory environments
   appearing with CXL.
 
 - Christophe Leroy has contributed some cleanup and consolidation work
   against the ARM pagetable dumping code in the series "mm: ptdump:
   Refactor CONFIG_DEBUG_WX and check_wx_pages debugfs attribute".
 
 - Luis Chamberlain has added some additional xarray selftesting in the
   series "test_xarray: advanced API multi-index tests".
 
 - Muhammad Usama Anjum has reworked the selftest code to make its
   human-readable output conform to the TAP ("Test Anything Protocol")
   format.  Amongst other things, this opens up the use of third-party
   tools to parse and process out selftesting results.
 
 - Ryan Roberts has added fork()-time PTE batching of THP ptes in the
   series "mm/memory: optimize fork() with PTE-mapped THP".  Mainly
   targeted at arm64, this significantly speeds up fork() when the process
   has a large number of pte-mapped folios.
 
 - David Hildenbrand also gets in on the THP pte batching game in his
   series "mm/memory: optimize unmap/zap with PTE-mapped THP".  It
   implements batching during munmap() and other pte teardown situations.
   The microbenchmark improvements are nice.
 
 - And in the series "Transparent Contiguous PTEs for User Mappings" Ryan
   Roberts further utilizes arm's pte's contiguous bit ("contpte
   mappings").  Kernel build times on arm64 improved nicely.  Ryan's series
   "Address some contpte nits" provides some followup work.
 
 - In the series "mm/hugetlb: Restore the reservation" Breno Leitao has
   fixed an obscure hugetlb race which was causing unnecessary page faults.
   He has also added a reproducer under the selftest code.
 
 - In the series "selftests/mm: Output cleanups for the compaction test",
   Mark Brown did what the title claims.
 
 - Kinsey Ho has added the series "mm/mglru: code cleanup and refactoring".
 
 - Even more zswap material from Nhat Pham.  The series "fix and extend
   zswap kselftests" does as claimed.
 
 - In the series "Introduce cpu_dcache_is_aliasing() to fix DAX
   regression" Mathieu Desnoyers has cleaned up and fixed rather a mess in
   our handling of DAX on archiecctures which have virtually aliasing data
   caches.  The arm architecture is the main beneficiary.
 
 - Lokesh Gidra's series "per-vma locks in userfaultfd" provides dramatic
   improvements in worst-case mmap_lock hold times during certain
   userfaultfd operations.
 
 - Some page_owner enhancements and maintenance work from Oscar Salvador
   in his series
 
 	"page_owner: print stacks and their outstanding allocations"
 	"page_owner: Fixup and cleanup"
 
 - Uladzislau Rezki has contributed some vmalloc scalability improvements
   in his series "Mitigate a vmap lock contention".  It realizes a 12x
   improvement for a certain microbenchmark.
 
 - Some kexec/crash cleanup work from Baoquan He in the series "Split
   crash out from kexec and clean up related config items".
 
 - Some zsmalloc maintenance work from Chengming Zhou in the series
 
 	"mm/zsmalloc: fix and optimize objects/page migration"
 	"mm/zsmalloc: some cleanup for get/set_zspage_mapping()"
 
 - Zi Yan has taught the MM to perform compaction on folios larger than
   order=0.  This a step along the path to implementaton of the merging of
   large anonymous folios.  The series is named "Enable >0 order folio
   memory compaction".
 
 - Christoph Hellwig has done quite a lot of cleanup work in the
   pagecache writeback code in his series "convert write_cache_pages() to
   an iterator".
 
 - Some modest hugetlb cleanups and speedups in Vishal Moola's series
   "Handle hugetlb faults under the VMA lock".
 
 - Zi Yan has changed the page splitting code so we can split huge pages
   into sizes other than order-0 to better utilize large folios.  The
   series is named "Split a folio to any lower order folios".
 
 - David Hildenbrand has contributed the series "mm: remove
   total_mapcount()", a cleanup.
 
 - Matthew Wilcox has sought to improve the performance of bulk memory
   freeing in his series "Rearrange batched folio freeing".
 
 - Gang Li's series "hugetlb: parallelize hugetlb page init on boot"
   provides large improvements in bootup times on large machines which are
   configured to use large numbers of hugetlb pages.
 
 - Matthew Wilcox's series "PageFlags cleanups" does that.
 
 - Qi Zheng's series "minor fixes and supplement for ptdesc" does that
   also.  S390 is affected.
 
 - Cleanups to our pagemap utility functions from Peter Xu in his series
   "mm/treewide: Replace pXd_large() with pXd_leaf()".
 
 - Nico Pache has fixed a few things with our hugepage selftests in his
   series "selftests/mm: Improve Hugepage Test Handling in MM Selftests".
 
 - Also, of course, many singleton patches to many things.  Please see
   the individual changelogs for details.
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Merge tag 'mm-stable-2024-03-13-20-04' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:

 - Sumanth Korikkar has taught s390 to allocate hotplug-time page frames
   from hotplugged memory rather than only from main memory. Series
   "implement "memmap on memory" feature on s390".

 - More folio conversions from Matthew Wilcox in the series

	"Convert memcontrol charge moving to use folios"
	"mm: convert mm counter to take a folio"

 - Chengming Zhou has optimized zswap's rbtree locking, providing
   significant reductions in system time and modest but measurable
   reductions in overall runtimes. The series is "mm/zswap: optimize the
   scalability of zswap rb-tree".

 - Chengming Zhou has also provided the series "mm/zswap: optimize zswap
   lru list" which provides measurable runtime benefits in some
   swap-intensive situations.

 - And Chengming Zhou further optimizes zswap in the series "mm/zswap:
   optimize for dynamic zswap_pools". Measured improvements are modest.

 - zswap cleanups and simplifications from Yosry Ahmed in the series
   "mm: zswap: simplify zswap_swapoff()".

 - In the series "Add DAX ABI for memmap_on_memory", Vishal Verma has
   contributed several DAX cleanups as well as adding a sysfs tunable to
   control the memmap_on_memory setting when the dax device is
   hotplugged as system memory.

 - Johannes Weiner has added the large series "mm: zswap: cleanups",
   which does that.

 - More DAMON work from SeongJae Park in the series

	"mm/damon: make DAMON debugfs interface deprecation unignorable"
	"selftests/damon: add more tests for core functionalities and corner cases"
	"Docs/mm/damon: misc readability improvements"
	"mm/damon: let DAMOS feeds and tame/auto-tune itself"

 - In the series "mm/mempolicy: weighted interleave mempolicy and sysfs
   extension" Rakie Kim has developed a new mempolicy interleaving
   policy wherein we allocate memory across nodes in a weighted fashion
   rather than uniformly. This is beneficial in heterogeneous memory
   environments appearing with CXL.

 - Christophe Leroy has contributed some cleanup and consolidation work
   against the ARM pagetable dumping code in the series "mm: ptdump:
   Refactor CONFIG_DEBUG_WX and check_wx_pages debugfs attribute".

 - Luis Chamberlain has added some additional xarray selftesting in the
   series "test_xarray: advanced API multi-index tests".

 - Muhammad Usama Anjum has reworked the selftest code to make its
   human-readable output conform to the TAP ("Test Anything Protocol")
   format. Amongst other things, this opens up the use of third-party
   tools to parse and process out selftesting results.

 - Ryan Roberts has added fork()-time PTE batching of THP ptes in the
   series "mm/memory: optimize fork() with PTE-mapped THP". Mainly
   targeted at arm64, this significantly speeds up fork() when the
   process has a large number of pte-mapped folios.

 - David Hildenbrand also gets in on the THP pte batching game in his
   series "mm/memory: optimize unmap/zap with PTE-mapped THP". It
   implements batching during munmap() and other pte teardown
   situations. The microbenchmark improvements are nice.

 - And in the series "Transparent Contiguous PTEs for User Mappings"
   Ryan Roberts further utilizes arm's pte's contiguous bit ("contpte
   mappings"). Kernel build times on arm64 improved nicely. Ryan's
   series "Address some contpte nits" provides some followup work.

 - In the series "mm/hugetlb: Restore the reservation" Breno Leitao has
   fixed an obscure hugetlb race which was causing unnecessary page
   faults. He has also added a reproducer under the selftest code.

 - In the series "selftests/mm: Output cleanups for the compaction
   test", Mark Brown did what the title claims.

 - Kinsey Ho has added the series "mm/mglru: code cleanup and
   refactoring".

 - Even more zswap material from Nhat Pham. The series "fix and extend
   zswap kselftests" does as claimed.

 - In the series "Introduce cpu_dcache_is_aliasing() to fix DAX
   regression" Mathieu Desnoyers has cleaned up and fixed rather a mess
   in our handling of DAX on archiecctures which have virtually aliasing
   data caches. The arm architecture is the main beneficiary.

 - Lokesh Gidra's series "per-vma locks in userfaultfd" provides
   dramatic improvements in worst-case mmap_lock hold times during
   certain userfaultfd operations.

 - Some page_owner enhancements and maintenance work from Oscar Salvador
   in his series

	"page_owner: print stacks and their outstanding allocations"
	"page_owner: Fixup and cleanup"

 - Uladzislau Rezki has contributed some vmalloc scalability
   improvements in his series "Mitigate a vmap lock contention". It
   realizes a 12x improvement for a certain microbenchmark.

 - Some kexec/crash cleanup work from Baoquan He in the series "Split
   crash out from kexec and clean up related config items".

 - Some zsmalloc maintenance work from Chengming Zhou in the series

	"mm/zsmalloc: fix and optimize objects/page migration"
	"mm/zsmalloc: some cleanup for get/set_zspage_mapping()"

 - Zi Yan has taught the MM to perform compaction on folios larger than
   order=0. This a step along the path to implementaton of the merging
   of large anonymous folios. The series is named "Enable >0 order folio
   memory compaction".

 - Christoph Hellwig has done quite a lot of cleanup work in the
   pagecache writeback code in his series "convert write_cache_pages()
   to an iterator".

 - Some modest hugetlb cleanups and speedups in Vishal Moola's series
   "Handle hugetlb faults under the VMA lock".

 - Zi Yan has changed the page splitting code so we can split huge pages
   into sizes other than order-0 to better utilize large folios. The
   series is named "Split a folio to any lower order folios".

 - David Hildenbrand has contributed the series "mm: remove
   total_mapcount()", a cleanup.

 - Matthew Wilcox has sought to improve the performance of bulk memory
   freeing in his series "Rearrange batched folio freeing".

 - Gang Li's series "hugetlb: parallelize hugetlb page init on boot"
   provides large improvements in bootup times on large machines which
   are configured to use large numbers of hugetlb pages.

 - Matthew Wilcox's series "PageFlags cleanups" does that.

 - Qi Zheng's series "minor fixes and supplement for ptdesc" does that
   also. S390 is affected.

 - Cleanups to our pagemap utility functions from Peter Xu in his series
   "mm/treewide: Replace pXd_large() with pXd_leaf()".

 - Nico Pache has fixed a few things with our hugepage selftests in his
   series "selftests/mm: Improve Hugepage Test Handling in MM
   Selftests".

 - Also, of course, many singleton patches to many things. Please see
   the individual changelogs for details.

* tag 'mm-stable-2024-03-13-20-04' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (435 commits)
  mm/zswap: remove the memcpy if acomp is not sleepable
  crypto: introduce: acomp_is_async to expose if comp drivers might sleep
  memtest: use {READ,WRITE}_ONCE in memory scanning
  mm: prohibit the last subpage from reusing the entire large folio
  mm: recover pud_leaf() definitions in nopmd case
  selftests/mm: skip the hugetlb-madvise tests on unmet hugepage requirements
  selftests/mm: skip uffd hugetlb tests with insufficient hugepages
  selftests/mm: dont fail testsuite due to a lack of hugepages
  mm/huge_memory: skip invalid debugfs new_order input for folio split
  mm/huge_memory: check new folio order when split a folio
  mm, vmscan: retry kswapd's priority loop with cache_trim_mode off on failure
  mm: add an explicit smp_wmb() to UFFDIO_CONTINUE
  mm: fix list corruption in put_pages_list
  mm: remove folio from deferred split list before uncharging it
  filemap: avoid unnecessary major faults in filemap_fault()
  mm,page_owner: drop unnecessary check
  mm,page_owner: check for null stack_record before bumping its refcount
  mm: swap: fix race between free_swap_and_cache() and swapoff()
  mm/treewide: align up pXd_leaf() retval across archs
  mm/treewide: drop pXd_large()
  ...
2024-03-14 17:43:30 -07:00
Paolo Bonzini
961e2bfcf3 KVM/arm64 updates for 6.9
- Infrastructure for building KVM's trap configuration based on the
    architectural features (or lack thereof) advertised in the VM's ID
    registers
 
  - Support for mapping vfio-pci BARs as Normal-NC (vaguely similar to
    x86's WC) at stage-2, improving the performance of interacting with
    assigned devices that can tolerate it
 
  - Conversion of KVM's representation of LPIs to an xarray, utilized to
    address serialization some of the serialization on the LPI injection
    path
 
  - Support for _architectural_ VHE-only systems, advertised through the
    absence of FEAT_E2H0 in the CPU's ID register
 
  - Miscellaneous cleanups, fixes, and spelling corrections to KVM and
    selftests
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Merge tag 'kvmarm-6.9' of https://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm64 updates for 6.9

 - Infrastructure for building KVM's trap configuration based on the
   architectural features (or lack thereof) advertised in the VM's ID
   registers

 - Support for mapping vfio-pci BARs as Normal-NC (vaguely similar to
   x86's WC) at stage-2, improving the performance of interacting with
   assigned devices that can tolerate it

 - Conversion of KVM's representation of LPIs to an xarray, utilized to
   address serialization some of the serialization on the LPI injection
   path

 - Support for _architectural_ VHE-only systems, advertised through the
   absence of FEAT_E2H0 in the CPU's ID register

 - Miscellaneous cleanups, fixes, and spelling corrections to KVM and
   selftests
2024-03-11 10:02:32 -04:00
Paolo Bonzini
233d0bc4d8 LoongArch KVM changes for v6.9
1. Set reserved bits as zero in CPUCFG.
 2. Start SW timer only when vcpu is blocking.
 3. Do not restart SW timer when it is expired.
 4. Remove unnecessary CSR register saving during enter guest.
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Merge tag 'loongarch-kvm-6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson into HEAD

LoongArch KVM changes for v6.9

* Set reserved bits as zero in CPUCFG.
* Start SW timer only when vcpu is blocking.
* Do not restart SW timer when it is expired.
* Remove unnecessary CSR register saving during enter guest.
2024-03-11 09:56:54 -04:00
Peter Xu
bd18b68822 mm/powerpc: replace pXd_is_leaf() with pXd_leaf()
They're the same macros underneath.  Drop pXd_is_leaf(), instead always use
pXd_leaf().

At the meantime, instead of renames, drop the pXd_is_leaf() fallback
definitions directly in arch/powerpc/include/asm/pgtable.h.  because
similar fallback macros for pXd_leaf() are already defined in
include/linux/pgtable.h.

Link: https://lkml.kernel.org/r/20240305043750.93762-3-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Suggested-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@kernel.org>
Cc: "Naveen N. Rao" <naveen.n.rao@linux.ibm.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-03-06 13:04:19 -08:00
Oliver Upton
284851ee5c KVM: Get rid of return value from kvm_arch_create_vm_debugfs()
The general expectation with debugfs is that any initialization failure
is nonfatal. Nevertheless, kvm_arch_create_vm_debugfs() allows
implementations to return an error and kvm_create_vm_debugfs() allows
that to fail VM creation.

Change to a void return to discourage architectures from making debugfs
failures fatal for the VM. Seems like everyone already had the right
idea, as all implementations already return 0 unconditionally.

Acked-by: Marc Zyngier <maz@kernel.org>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Link: https://lore.kernel.org/r/20240216155941.2029458-1-oliver.upton@linux.dev
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-02-23 21:44:58 +00:00
Nathan Chancellor
2947a4567f treewide: update LLVM Bugzilla links
LLVM moved their issue tracker from their own Bugzilla instance to GitHub
issues.  While all of the links are still valid, they may not necessarily
show the most up to date information around the issues, as all updates
will occur on GitHub, not Bugzilla.

Another complication is that the Bugzilla issue number is not always the
same as the GitHub issue number.  Thankfully, LLVM maintains this mapping
through two shortlinks:

  https://llvm.org/bz<num> -> https://bugs.llvm.org/show_bug.cgi?id=<num>
  https://llvm.org/pr<num> -> https://github.com/llvm/llvm-project/issues/<mapped_num>

Switch all "https://bugs.llvm.org/show_bug.cgi?id=<num>" links to the
"https://llvm.org/pr<num>" shortlink so that the links show the most up to
date information.  Each migrated issue links back to the Bugzilla entry,
so there should be no loss of fidelity of information here.

Link: https://lkml.kernel.org/r/20240109-update-llvm-links-v1-3-eb09b59db071@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Fangrui Song <maskray@google.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Mykola Lysenko <mykolal@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-22 15:38:51 -08:00
Madhavan Srinivasan
c2ed087ed3 powerpc: Add Power11 architected and raw mode
Add CPU table entries for raw and architected mode. Most fields are
copied from the Power10 table entries.

CPU, MMU and user (ELF_HWCAP) features are unchanged vs P10. However
userspace can detect P11 because the AT_PLATFORM value changes to
"power11".

The logical PVR value of 0x0F000007, passed to firmware via the
ibm_arch_vec, indicates the kernel can support a P11 compatible CPU,
which means at least ISA v3.1 compliant.

Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240221044623.1598642-1-mpe@ellerman.id.au
2024-02-21 23:11:00 +11:00
Amit Machhiwal
20c8c4dafe KVM: PPC: Book3S HV: Fix L2 guest reboot failure due to empty 'arch_compat'
Currently, rebooting a pseries nested qemu-kvm guest (L2) results in
below error as L1 qemu sends PVR value 'arch_compat' == 0 via
ppc_set_compat ioctl. This triggers a condition failure in
kvmppc_set_arch_compat() resulting in an EINVAL.

qemu-system-ppc64: Unable to set CPU compatibility mode in KVM: Invalid
argument

Also, a value of 0 for arch_compat generally refers the default
compatibility of the host. But, arch_compat, being a Guest Wide Element
in nested API v2, cannot be set to 0 in GSB as PowerVM (L0) expects a
non-zero value. A value of 0 triggers a kernel trap during a reboot and
consequently causes it to fail:

[   22.106360] reboot: Restarting system
KVM: unknown exit, hardware reason ffffffffffffffea
NIP 0000000000000100   LR 000000000000fe44 CTR 0000000000000000 XER 0000000020040092 CPU#0
MSR 0000000000001000 HID0 0000000000000000  HF 6c000000 iidx 3 didx 3
TB 00000000 00000000 DECR 0
GPR00 0000000000000000 0000000000000000 c000000002a8c300 000000007fe00000
GPR04 0000000000000000 0000000000000000 0000000000001002 8000000002803033
GPR08 000000000a000000 0000000000000000 0000000000000004 000000002fff0000
GPR12 0000000000000000 c000000002e10000 0000000105639200 0000000000000004
GPR16 0000000000000000 000000010563a090 0000000000000000 0000000000000000
GPR20 0000000105639e20 00000001056399c8 00007fffe54abab0 0000000105639288
GPR24 0000000000000000 0000000000000001 0000000000000001 0000000000000000
GPR28 0000000000000000 0000000000000000 c000000002b30840 0000000000000000
CR 00000000  [ -  -  -  -  -  -  -  -  ]     RES 000@ffffffffffffffff
 SRR0 0000000000000000  SRR1 0000000000000000    PVR 0000000000800200 VRSAVE 0000000000000000
SPRG0 0000000000000000 SPRG1 0000000000000000  SPRG2 0000000000000000  SPRG3 0000000000000000
SPRG4 0000000000000000 SPRG5 0000000000000000  SPRG6 0000000000000000  SPRG7 0000000000000000
HSRR0 0000000000000000 HSRR1 0000000000000000
 CFAR 0000000000000000
 LPCR 0000000000020400
 PTCR 0000000000000000   DAR 0000000000000000  DSISR 0000000000000000

 kernel:trap=0xffffffea | pc=0x100 | msr=0x1000

This patch updates kvmppc_set_arch_compat() to use the host PVR value if
'compat_pvr' == 0 indicating that qemu doesn't want to enforce any
specific PVR compat mode.

The relevant part of the code might need a rework if PowerVM implements
a support for `arch_compat == 0` in nestedv2 API.

Fixes: 19d31c5f1157 ("KVM: PPC: Add support for nestedv2 guests")
Reviewed-by: "Aneesh Kumar K.V (IBM)" <aneesh.kumar@kernel.org>
Reviewed-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Signed-off-by: Amit Machhiwal <amachhiw@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240207054526.3720087-1-amachhiw@linux.ibm.com
2024-02-20 22:32:20 +11:00
Paolo Bonzini
61df71ee99 kvm: move "select IRQ_BYPASS_MANAGER" to common code
CONFIG_IRQ_BYPASS_MANAGER is a dependency of the common code included by
CONFIG_HAVE_KVM_IRQ_BYPASS.  There is no advantage in adding the corresponding
"select" directive to each architecture.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-02-08 08:45:34 -05:00
Linus Torvalds
09d1c6a80f Generic:
- Use memdup_array_user() to harden against overflow.
 
 - Unconditionally advertise KVM_CAP_DEVICE_CTRL for all architectures.
 
 - Clean up Kconfigs that all KVM architectures were selecting
 
 - New functionality around "guest_memfd", a new userspace API that
   creates an anonymous file and returns a file descriptor that refers
   to it.  guest_memfd files are bound to their owning virtual machine,
   cannot be mapped, read, or written by userspace, and cannot be resized.
   guest_memfd files do however support PUNCH_HOLE, which can be used to
   switch a memory area between guest_memfd and regular anonymous memory.
 
 - New ioctl KVM_SET_MEMORY_ATTRIBUTES allowing userspace to specify
   per-page attributes for a given page of guest memory; right now the
   only attribute is whether the guest expects to access memory via
   guest_memfd or not, which in Confidential SVMs backed by SEV-SNP,
   TDX or ARM64 pKVM is checked by firmware or hypervisor that guarantees
   confidentiality (AMD PSP, Intel TDX module, or EL2 in the case of pKVM).
 
 x86:
 
 - Support for "software-protected VMs" that can use the new guest_memfd
   and page attributes infrastructure.  This is mostly useful for testing,
   since there is no pKVM-like infrastructure to provide a meaningfully
   reduced TCB.
 
 - Fix a relatively benign off-by-one error when splitting huge pages during
   CLEAR_DIRTY_LOG.
 
 - Fix a bug where KVM could incorrectly test-and-clear dirty bits in non-leaf
   TDP MMU SPTEs if a racing thread replaces a huge SPTE with a non-huge SPTE.
 
 - Use more generic lockdep assertions in paths that don't actually care
   about whether the caller is a reader or a writer.
 
 - let Xen guests opt out of having PV clock reported as "based on a stable TSC",
   because some of them don't expect the "TSC stable" bit (added to the pvclock
   ABI by KVM, but never set by Xen) to be set.
 
 - Revert a bogus, made-up nested SVM consistency check for TLB_CONTROL.
 
 - Advertise flush-by-ASID support for nSVM unconditionally, as KVM always
   flushes on nested transitions, i.e. always satisfies flush requests.  This
   allows running bleeding edge versions of VMware Workstation on top of KVM.
 
 - Sanity check that the CPU supports flush-by-ASID when enabling SEV support.
 
 - On AMD machines with vNMI, always rely on hardware instead of intercepting
   IRET in some cases to detect unmasking of NMIs
 
 - Support for virtualizing Linear Address Masking (LAM)
 
 - Fix a variety of vPMU bugs where KVM fail to stop/reset counters and other state
   prior to refreshing the vPMU model.
 
 - Fix a double-overflow PMU bug by tracking emulated counter events using a
   dedicated field instead of snapshotting the "previous" counter.  If the
   hardware PMC count triggers overflow that is recognized in the same VM-Exit
   that KVM manually bumps an event count, KVM would pend PMIs for both the
   hardware-triggered overflow and for KVM-triggered overflow.
 
 - Turn off KVM_WERROR by default for all configs so that it's not
   inadvertantly enabled by non-KVM developers, which can be problematic for
   subsystems that require no regressions for W=1 builds.
 
 - Advertise all of the host-supported CPUID bits that enumerate IA32_SPEC_CTRL
   "features".
 
 - Don't force a masterclock update when a vCPU synchronizes to the current TSC
   generation, as updating the masterclock can cause kvmclock's time to "jump"
   unexpectedly, e.g. when userspace hotplugs a pre-created vCPU.
 
 - Use RIP-relative address to read kvm_rebooting in the VM-Enter fault paths,
   partly as a super minor optimization, but mostly to make KVM play nice with
   position independent executable builds.
 
 - Guard KVM-on-HyperV's range-based TLB flush hooks with an #ifdef on
   CONFIG_HYPERV as a minor optimization, and to self-document the code.
 
 - Add CONFIG_KVM_HYPERV to allow disabling KVM support for HyperV "emulation"
   at build time.
 
 ARM64:
 
 - LPA2 support, adding 52bit IPA/PA capability for 4kB and 16kB
   base granule sizes. Branch shared with the arm64 tree.
 
 - Large Fine-Grained Trap rework, bringing some sanity to the
   feature, although there is more to come. This comes with
   a prefix branch shared with the arm64 tree.
 
 - Some additional Nested Virtualization groundwork, mostly
   introducing the NV2 VNCR support and retargetting the NV
   support to that version of the architecture.
 
 - A small set of vgic fixes and associated cleanups.
 
 Loongarch:
 
 - Optimization for memslot hugepage checking
 
 - Cleanup and fix some HW/SW timer issues
 
 - Add LSX/LASX (128bit/256bit SIMD) support
 
 RISC-V:
 
 - KVM_GET_REG_LIST improvement for vector registers
 
 - Generate ISA extension reg_list using macros in get-reg-list selftest
 
 - Support for reporting steal time along with selftest
 
 s390:
 
 - Bugfixes
 
 Selftests:
 
 - Fix an annoying goof where the NX hugepage test prints out garbage
   instead of the magic token needed to run the test.
 
 - Fix build errors when a header is delete/moved due to a missing flag
   in the Makefile.
 
 - Detect if KVM bugged/killed a selftest's VM and print out a helpful
   message instead of complaining that a random ioctl() failed.
 
 - Annotate the guest printf/assert helpers with __printf(), and fix the
   various bugs that were lurking due to lack of said annotation.
 
 There are two non-KVM patches buried in the middle of guest_memfd support:
 
   fs: Rename anon_inode_getfile_secure() and anon_inode_getfd_secure()
   mm: Add AS_UNMOVABLE to mark mapping as completely unmovable
 
 The first is small and mostly suggested-by Christian Brauner; the second
 a bit less so but it was written by an mm person (Vlastimil Babka).
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm updates from Paolo Bonzini:
 "Generic:

   - Use memdup_array_user() to harden against overflow.

   - Unconditionally advertise KVM_CAP_DEVICE_CTRL for all
     architectures.

   - Clean up Kconfigs that all KVM architectures were selecting

   - New functionality around "guest_memfd", a new userspace API that
     creates an anonymous file and returns a file descriptor that refers
     to it. guest_memfd files are bound to their owning virtual machine,
     cannot be mapped, read, or written by userspace, and cannot be
     resized. guest_memfd files do however support PUNCH_HOLE, which can
     be used to switch a memory area between guest_memfd and regular
     anonymous memory.

   - New ioctl KVM_SET_MEMORY_ATTRIBUTES allowing userspace to specify
     per-page attributes for a given page of guest memory; right now the
     only attribute is whether the guest expects to access memory via
     guest_memfd or not, which in Confidential SVMs backed by SEV-SNP,
     TDX or ARM64 pKVM is checked by firmware or hypervisor that
     guarantees confidentiality (AMD PSP, Intel TDX module, or EL2 in
     the case of pKVM).

  x86:

   - Support for "software-protected VMs" that can use the new
     guest_memfd and page attributes infrastructure. This is mostly
     useful for testing, since there is no pKVM-like infrastructure to
     provide a meaningfully reduced TCB.

   - Fix a relatively benign off-by-one error when splitting huge pages
     during CLEAR_DIRTY_LOG.

   - Fix a bug where KVM could incorrectly test-and-clear dirty bits in
     non-leaf TDP MMU SPTEs if a racing thread replaces a huge SPTE with
     a non-huge SPTE.

   - Use more generic lockdep assertions in paths that don't actually
     care about whether the caller is a reader or a writer.

   - let Xen guests opt out of having PV clock reported as "based on a
     stable TSC", because some of them don't expect the "TSC stable" bit
     (added to the pvclock ABI by KVM, but never set by Xen) to be set.

   - Revert a bogus, made-up nested SVM consistency check for
     TLB_CONTROL.

   - Advertise flush-by-ASID support for nSVM unconditionally, as KVM
     always flushes on nested transitions, i.e. always satisfies flush
     requests. This allows running bleeding edge versions of VMware
     Workstation on top of KVM.

   - Sanity check that the CPU supports flush-by-ASID when enabling SEV
     support.

   - On AMD machines with vNMI, always rely on hardware instead of
     intercepting IRET in some cases to detect unmasking of NMIs

   - Support for virtualizing Linear Address Masking (LAM)

   - Fix a variety of vPMU bugs where KVM fail to stop/reset counters
     and other state prior to refreshing the vPMU model.

   - Fix a double-overflow PMU bug by tracking emulated counter events
     using a dedicated field instead of snapshotting the "previous"
     counter. If the hardware PMC count triggers overflow that is
     recognized in the same VM-Exit that KVM manually bumps an event
     count, KVM would pend PMIs for both the hardware-triggered overflow
     and for KVM-triggered overflow.

   - Turn off KVM_WERROR by default for all configs so that it's not
     inadvertantly enabled by non-KVM developers, which can be
     problematic for subsystems that require no regressions for W=1
     builds.

   - Advertise all of the host-supported CPUID bits that enumerate
     IA32_SPEC_CTRL "features".

   - Don't force a masterclock update when a vCPU synchronizes to the
     current TSC generation, as updating the masterclock can cause
     kvmclock's time to "jump" unexpectedly, e.g. when userspace
     hotplugs a pre-created vCPU.

   - Use RIP-relative address to read kvm_rebooting in the VM-Enter
     fault paths, partly as a super minor optimization, but mostly to
     make KVM play nice with position independent executable builds.

   - Guard KVM-on-HyperV's range-based TLB flush hooks with an #ifdef on
     CONFIG_HYPERV as a minor optimization, and to self-document the
     code.

   - Add CONFIG_KVM_HYPERV to allow disabling KVM support for HyperV
     "emulation" at build time.

  ARM64:

   - LPA2 support, adding 52bit IPA/PA capability for 4kB and 16kB base
     granule sizes. Branch shared with the arm64 tree.

   - Large Fine-Grained Trap rework, bringing some sanity to the
     feature, although there is more to come. This comes with a prefix
     branch shared with the arm64 tree.

   - Some additional Nested Virtualization groundwork, mostly
     introducing the NV2 VNCR support and retargetting the NV support to
     that version of the architecture.

   - A small set of vgic fixes and associated cleanups.

  Loongarch:

   - Optimization for memslot hugepage checking

   - Cleanup and fix some HW/SW timer issues

   - Add LSX/LASX (128bit/256bit SIMD) support

  RISC-V:

   - KVM_GET_REG_LIST improvement for vector registers

   - Generate ISA extension reg_list using macros in get-reg-list
     selftest

   - Support for reporting steal time along with selftest

  s390:

   - Bugfixes

  Selftests:

   - Fix an annoying goof where the NX hugepage test prints out garbage
     instead of the magic token needed to run the test.

   - Fix build errors when a header is delete/moved due to a missing
     flag in the Makefile.

   - Detect if KVM bugged/killed a selftest's VM and print out a helpful
     message instead of complaining that a random ioctl() failed.

   - Annotate the guest printf/assert helpers with __printf(), and fix
     the various bugs that were lurking due to lack of said annotation"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (185 commits)
  x86/kvm: Do not try to disable kvmclock if it was not enabled
  KVM: x86: add missing "depends on KVM"
  KVM: fix direction of dependency on MMU notifiers
  KVM: introduce CONFIG_KVM_COMMON
  KVM: arm64: Add missing memory barriers when switching to pKVM's hyp pgd
  KVM: arm64: vgic-its: Avoid potential UAF in LPI translation cache
  RISC-V: KVM: selftests: Add get-reg-list test for STA registers
  RISC-V: KVM: selftests: Add steal_time test support
  RISC-V: KVM: selftests: Add guest_sbi_probe_extension
  RISC-V: KVM: selftests: Move sbi_ecall to processor.c
  RISC-V: KVM: Implement SBI STA extension
  RISC-V: KVM: Add support for SBI STA registers
  RISC-V: KVM: Add support for SBI extension registers
  RISC-V: KVM: Add SBI STA info to vcpu_arch
  RISC-V: KVM: Add steal-update vcpu request
  RISC-V: KVM: Add SBI STA extension skeleton
  RISC-V: paravirt: Implement steal-time support
  RISC-V: Add SBI STA extension definitions
  RISC-V: paravirt: Add skeleton for pv-time support
  RISC-V: KVM: Fix indentation in kvm_riscv_vcpu_set_reg_csr()
  ...
2024-01-17 13:03:37 -08:00
Linus Torvalds
78273df7f6 header cleanups for 6.8
The goal is to get sched.h down to a type only header, so the main thing
 happening in this patchset is splitting out various _types.h headers and
 dependency fixups, as well as moving some things out of sched.h to
 better locations.
 
 This is prep work for the memory allocation profiling patchset which
 adds new sched.h interdepencencies.
 
 Testing - it's been in -next, and fixes from pretty much all
 architectures have percolated in - nothing major.
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Merge tag 'header_cleanup-2024-01-10' of https://evilpiepirate.org/git/bcachefs

Pull header cleanups from Kent Overstreet:
 "The goal is to get sched.h down to a type only header, so the main
  thing happening in this patchset is splitting out various _types.h
  headers and dependency fixups, as well as moving some things out of
  sched.h to better locations.

  This is prep work for the memory allocation profiling patchset which
  adds new sched.h interdepencencies"

* tag 'header_cleanup-2024-01-10' of https://evilpiepirate.org/git/bcachefs: (51 commits)
  Kill sched.h dependency on rcupdate.h
  kill unnecessary thread_info.h include
  Kill unnecessary kernel.h include
  preempt.h: Kill dependency on list.h
  rseq: Split out rseq.h from sched.h
  LoongArch: signal.c: add header file to fix build error
  restart_block: Trim includes
  lockdep: move held_lock to lockdep_types.h
  sem: Split out sem_types.h
  uidgid: Split out uidgid_types.h
  seccomp: Split out seccomp_types.h
  refcount: Split out refcount_types.h
  uapi/linux/resource.h: fix include
  x86/signal: kill dependency on time.h
  syscall_user_dispatch.h: split out *_types.h
  mm_types_task.h: Trim dependencies
  Split out irqflags_types.h
  ipc: Kill bogus dependency on spinlock.h
  shm: Slim down dependencies
  workqueue: Split out workqueue_types.h
  ...
2024-01-10 16:43:55 -08:00
Paolo Bonzini
fb872da8e7 Common KVM changes for 6.8:
- Use memdup_array_user() to harden against overflow.
 
  - Unconditionally advertise KVM_CAP_DEVICE_CTRL for all architectures.
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Merge tag 'kvm-x86-generic-6.8' of https://github.com/kvm-x86/linux into HEAD

Common KVM changes for 6.8:

 - Use memdup_array_user() to harden against overflow.

 - Unconditionally advertise KVM_CAP_DEVICE_CTRL for all architectures.
2024-01-08 08:09:57 -05:00
Paolo Bonzini
caadf876bb KVM: introduce CONFIG_KVM_COMMON
CONFIG_HAVE_KVM is currently used by some architectures to either
enabled the KVM config proper, or to enable host-side code that is
not part of the KVM module.  However, CONFIG_KVM's "select" statement
in virt/kvm/Kconfig corresponds to a third meaning, namely to
enable common Kconfigs required by all architectures that support
KVM.

These three meanings can be replaced respectively by an
architecture-specific Kconfig, by IS_ENABLED(CONFIG_KVM), or by
a new Kconfig symbol that is in turn selected by the
architecture-specific "config KVM".

Start by introducing such a new Kconfig symbol, CONFIG_KVM_COMMON.
Unlike CONFIG_HAVE_KVM, it is selected by CONFIG_KVM, not by
architecture code, and it brings in all dependencies of common
KVM code.  In particular, INTERVAL_TREE was missing in loongarch
and riscv, so that is another thing that is fixed.

Fixes: 8132d887a702 ("KVM: remove CONFIG_HAVE_KVM_EVENTFD", 2023-12-08)
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Closes: https://lore.kernel.org/all/44907c6b-c5bd-4e4a-a921-e4d3825539d8@infradead.org/
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-01-08 08:09:38 -05:00
Michael Ellerman
44a1aad2fe Merge branch 'topic/ppc-kvm' into next
Merge our topic branch containing KVM related patches.
2023-12-29 15:30:45 +11:00
Kent Overstreet
1e2f2d3199 Kill sched.h dependency on rcupdate.h
by moving cond_resched_rcu() to rcupdate_wait.h, we can kill another big
sched.h dependency.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-12-27 11:50:20 -05:00
Paolo Bonzini
c5b31cc237 KVM: remove CONFIG_HAVE_KVM_IRQFD
All platforms with a kernel irqchip have support for irqfd.  Unify the
two configuration items so that userspace can expect to use irqfd to
inject interrupts into the irqchip.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-12-08 15:43:33 -05:00
Paolo Bonzini
8132d887a7 KVM: remove CONFIG_HAVE_KVM_EVENTFD
virt/kvm/eventfd.c is compiled unconditionally, meaning that the ioeventfds
member of struct kvm is accessed unconditionally.  CONFIG_HAVE_KVM_EVENTFD
therefore must be defined for KVM common code to compile successfully,
remove it.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-12-08 15:43:33 -05:00
Jordan Niethe
180c6b072b KVM: PPC: Book3S HV nestedv2: Do not cancel pending decrementer exception
In the nestedv2 case, if there is a pending decrementer exception, the
L1 must get the L2's timebase from the L0 to see if the exception should
be cancelled. This adds the overhead of a H_GUEST_GET_STATE call to the
likely case in which the decrementer should not be cancelled.

Avoid this logic for the nestedv2 case.

Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231201132618.555031-13-vaibhav@linux.ibm.com
2023-12-07 23:33:08 +11:00
Jordan Niethe
797a5af8fc KVM: PPC: Reduce reliance on analyse_instr() in mmio emulation
Commit 709236039964 ("KVM: PPC: Reimplement non-SIMD LOAD/STORE
instruction mmio emulation with analyse_instr() input") and
commit 2b33cb585f94 ("KVM: PPC: Reimplement LOAD_FP/STORE_FP instruction
mmio emulation with analyse_instr() input") made
kvmppc_emulate_loadstore() use the results from analyse_instr() for
instruction emulation. In particular the effective address from
analyse_instr() is used for UPDATE type instructions and fact that
op.val is all ready endian corrected is used in the STORE case.

However, these changes now have some negative implications for the
nestedv2 case.  For analyse_instr() to determine the correct effective
address, the GPRs must be loaded from the L0. This is not needed as
vcpu->arch.vaddr_accessed is already set. Change back to using
vcpu->arch.vaddr_accessed.

In the STORE case, use kvmppc_get_gpr() value instead of the op.val.
kvmppc_get_gpr() will reload from the L0 if needed in the nestedv2 case.
This means if a byte reversal is needed must now be passed to
kvmppc_handle_store() like in the kvmppc_handle_load() case.

This means the call to kvmhv_nestedv2_reload_ptregs() can be avoided as
there is no concern about op.val being stale. Drop the call to
kvmhv_nestedv2_mark_dirty_ptregs() as without the call to
kvmhv_nestedv2_reload_ptregs(), stale state could be marked as valid.

This is fine as the required marking things dirty is already handled for
the UPDATE case by the call to kvmppc_set_gpr(). For LOADs, it is
handled in kvmppc_complete_mmio_load(). This is called either directly
in __kvmppc_handle_load() if the load can be handled in KVM, or on the
next kvm_arch_vcpu_ioctl_run() if an exit was required.

Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231201132618.555031-12-vaibhav@linux.ibm.com
2023-12-07 23:33:08 +11:00
Jordan Niethe
db1dcfae1d KVM: PPC: Book3S HV nestedv2: Register the VPA with the L0
In the nestedv2 case, the L1 may register the L2's VPA with the L0. This
allows the L0 to manage the L2's dispatch count, as well as enable
possible performance optimisations by seeing if certain resources are
not being used by the L2 (such as the PMCs).

Use the H_GUEST_SET_STATE call to inform the L0 of the L2's VPA
address. This can not be done in the H_GUEST_VCPU_RUN input buffer.

Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231201132618.555031-11-vaibhav@linux.ibm.com
2023-12-07 23:33:08 +11:00
Jordan Niethe
4bc8ff6f17 KVM: PPC: Book3S HV nestedv2: Do not call H_COPY_TOFROM_GUEST
H_COPY_TOFROM_GUEST is part of the nestedv1 API and so should not be
called by a nestedv2 host. Do not attempt to call it.

Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231201132618.555031-10-vaibhav@linux.ibm.com
2023-12-07 23:33:08 +11:00
Jordan Niethe
a9a3de530d KVM: PPC: Book3S HV nestedv2: Avoid msr check in kvmppc_handle_exit_hv()
The msr check in kvmppc_handle_exit_hv() is not needed for nestedv2 hosts,
skip the check to avoid a H_GUEST_GET_STATE hcall.

Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231201132618.555031-9-vaibhav@linux.ibm.com
2023-12-07 23:33:07 +11:00
Jordan Niethe
df938a5576 KVM: PPC: Book3S HV nestedv2: Do not inject certain interrupts
There is no need to inject an external interrupt in
kvmppc_book3s_irqprio_deliver() as the test for BOOK3S_IRQPRIO_EXTERNAL
in kvmhv_run_single_vcpu() before guest entry will raise LPCR_MER if
needed. There is also no need to inject the decrementer interrupt as
this will be raised within the L2 if needed. Avoiding these injections
reduces H_GUEST_GET_STATE hcalls by the L1.

Suggested-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231201132618.555031-8-vaibhav@linux.ibm.com
2023-12-07 23:33:07 +11:00
Nicholas Piggin
ecd10702ba KVM: PPC: Book3S HV: Handle pending exceptions on guest entry with MSR_EE
Commit 026728dc5d41 ("KVM: PPC: Book3S HV P9: Inject pending xive
interrupts at guest entry") changed guest entry so that if external
interrupts are enabled, BOOK3S_IRQPRIO_EXTERNAL is not tested for. Test
for this regardless of MSR_EE.

For an L1 host, do not inject an interrupt, but always
use LPCR_MER. If the L0 desires it can inject an interrupt.

Fixes: 026728dc5d41 ("KVM: PPC: Book3S HV P9: Inject pending xive interrupts at guest entry")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[jpn: use kvmpcc_get_msr(), write commit message]
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231201132618.555031-7-vaibhav@linux.ibm.com
2023-12-07 23:33:07 +11:00
Jordan Niethe
ec0f6639fa KVM: PPC: Book3S HV nestedv2: Ensure LPCR_MER bit is passed to the L0
LPCR_MER is conditionally set during entry to a guest if there is a
pending external interrupt. In the nestedv2 case, this change is not
being communicated to the L0, which means it is not being set in the L2.
Ensure the updated LPCR value is passed to the L0.

Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231201132618.555031-6-vaibhav@linux.ibm.com
2023-12-07 23:33:07 +11:00
Jordan Niethe
e678748a8d KVM: PPC: Book3S HV nestedv2: Get the PID only if needed to copy tofrom a guest
kvmhv_copy_tofrom_guest_radix() gets the PID at the start of the
function. If pid is not used, then this is a wasteful H_GUEST_GET_STATE
hcall for nestedv2 hosts. Move the assignment to where pid will be used.

Suggested-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231201132618.555031-5-vaibhav@linux.ibm.com
2023-12-07 23:33:07 +11:00
Jordan Niethe
63ccae78cd KVM: PPC: Book3S HV nestedv2: Do not check msr on hcalls
The check for a hcall coming from userspace is done for KVM-PR. This is
not supported for nestedv2 and the L0 will directly inject the necessary
exception to the L2 if userspace performs a hcall. Avoid checking the
MSR and thus avoid a H_GUEST_GET_STATE hcall in the L1.

Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231201132618.555031-4-vaibhav@linux.ibm.com
2023-12-07 23:33:07 +11:00
Jordan Niethe
7d370e1812 KVM: PPC: Book3S HV nestedv2: Invalidate RPT before deleting a guest
An L0 must invalidate the L2's RPT during H_GUEST_DELETE if this has not
already been done. This is a slow operation that means H_GUEST_DELETE
must return H_BUSY multiple times before completing. Invalidating the
tables before deleting the guest so there is less work for the L0 to do.

Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231201132618.555031-2-vaibhav@linux.ibm.com
2023-12-07 23:33:07 +11:00
Zhao Ke
e12d8e2602 powerpc: Add PVN support for HeXin C2000 processor
HeXin Tech Co. has applied for a new PVN from the OpenPower Community
for its new processor C2000. The OpenPower has assigned a new PVN
and this newly assigned PVN is 0x0066, add pvr register related
support for this PVN.

Signed-off-by: Zhao Ke <ke.zhao@shingroup.cn>
Link: https://discuss.openpower.foundation/t/how-to-get-a-new-pvr-for-processors-follow-power-isa/477/10
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231129075845.57976-1-ke.zhao@shingroup.cn
2023-12-01 21:15:33 +11:00
Wei Wang
63912245c1 KVM: move KVM_CAP_DEVICE_CTRL to the generic check
KVM_CAP_DEVICE_CTRL allows userspace to check if the kvm_device
framework (e.g. KVM_CREATE_DEVICE) is supported by KVM. Move
KVM_CAP_DEVICE_CTRL to the generic check for the two reasons:
1) it already supports arch agnostic usages (i.e. KVM_DEV_TYPE_VFIO).
For example, userspace VFIO implementation may needs to create
KVM_DEV_TYPE_VFIO on x86, riscv, or arm etc. It is simpler to have it
checked at the generic code than at each arch's code.
2) KVM_CREATE_DEVICE has been added to the generic code.

Link: https://lore.kernel.org/all/20221215115207.14784-1-wei.w.wang@intel.com
Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Acked-by: Anup Patel <anup@brainfault.org> (riscv)
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Link: https://lore.kernel.org/r/20230315101606.10636-1-wei.w.wang@intel.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-11-30 13:09:43 -08:00
Paolo Bonzini
6c370dc653 Merge branch 'kvm-guestmemfd' into HEAD
Introduce several new KVM uAPIs to ultimately create a guest-first memory
subsystem within KVM, a.k.a. guest_memfd.  Guest-first memory allows KVM
to provide features, enhancements, and optimizations that are kludgly
or outright impossible to implement in a generic memory subsystem.

The core KVM ioctl() for guest_memfd is KVM_CREATE_GUEST_MEMFD, which
similar to the generic memfd_create(), creates an anonymous file and
returns a file descriptor that refers to it.  Again like "regular"
memfd files, guest_memfd files live in RAM, have volatile storage,
and are automatically released when the last reference is dropped.
The key differences between memfd files (and every other memory subystem)
is that guest_memfd files are bound to their owning virtual machine,
cannot be mapped, read, or written by userspace, and cannot be resized.
guest_memfd files do however support PUNCH_HOLE, which can be used to
convert a guest memory area between the shared and guest-private states.

A second KVM ioctl(), KVM_SET_MEMORY_ATTRIBUTES, allows userspace to
specify attributes for a given page of guest memory.  In the long term,
it will likely be extended to allow userspace to specify per-gfn RWX
protections, including allowing memory to be writable in the guest
without it also being writable in host userspace.

The immediate and driving use case for guest_memfd are Confidential
(CoCo) VMs, specifically AMD's SEV-SNP, Intel's TDX, and KVM's own pKVM.
For such use cases, being able to map memory into KVM guests without
requiring said memory to be mapped into the host is a hard requirement.
While SEV+ and TDX prevent untrusted software from reading guest private
data by encrypting guest memory, pKVM provides confidentiality and
integrity *without* relying on memory encryption.  In addition, with
SEV-SNP and especially TDX, accessing guest private memory can be fatal
to the host, i.e. KVM must be prevent host userspace from accessing
guest memory irrespective of hardware behavior.

Long term, guest_memfd may be useful for use cases beyond CoCo VMs,
for example hardening userspace against unintentional accesses to guest
memory.  As mentioned earlier, KVM's ABI uses userspace VMA protections to
define the allow guest protection (with an exception granted to mapping
guest memory executable), and similarly KVM currently requires the guest
mapping size to be a strict subset of the host userspace mapping size.
Decoupling the mappings sizes would allow userspace to precisely map
only what is needed and with the required permissions, without impacting
guest performance.

A guest-first memory subsystem also provides clearer line of sight to
things like a dedicated memory pool (for slice-of-hardware VMs) and
elimination of "struct page" (for offload setups where userspace _never_
needs to DMA from or into guest memory).

guest_memfd is the result of 3+ years of development and exploration;
taking on memory management responsibilities in KVM was not the first,
second, or even third choice for supporting CoCo VMs.  But after many
failed attempts to avoid KVM-specific backing memory, and looking at
where things ended up, it is quite clear that of all approaches tried,
guest_memfd is the simplest, most robust, and most extensible, and the
right thing to do for KVM and the kernel at-large.

The "development cycle" for this version is going to be very short;
ideally, next week I will merge it as is in kvm/next, taking this through
the KVM tree for 6.8 immediately after the end of the merge window.
The series is still based on 6.6 (plus KVM changes for 6.7) so it
will require a small fixup for changes to get_file_rcu() introduced in
6.7 by commit 0ede61d8589c ("file: convert to SLAB_TYPESAFE_BY_RCU").
The fixup will be done as part of the merge commit, and most of the text
above will become the commit message for the merge.

Pending post-merge work includes:
- hugepage support
- looking into using the restrictedmem framework for guest memory
- introducing a testing mechanism to poison memory, possibly using
  the same memory attributes introduced here
- SNP and TDX support

There are two non-KVM patches buried in the middle of this series:

  fs: Rename anon_inode_getfile_secure() and anon_inode_getfd_secure()
  mm: Add AS_UNMOVABLE to mark mapping as completely unmovable

The first is small and mostly suggested-by Christian Brauner; the second
a bit less so but it was written by an mm person (Vlastimil Babka).
2023-11-14 08:31:31 -05:00
Sean Christopherson
eed52e434b KVM: Allow arch code to track number of memslot address spaces per VM
Let x86 track the number of address spaces on a per-VM basis so that KVM
can disallow SMM memslots for confidential VMs.  Confidentials VMs are
fundamentally incompatible with emulating SMM, which as the name suggests
requires being able to read and write guest memory and register state.

Disallowing SMM will simplify support for guest private memory, as KVM
will not need to worry about tracking memory attributes for multiple
address spaces (SMM is the only "non-default" address space across all
architectures).

Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fuad Tabba <tabba@google.com>
Tested-by: Fuad Tabba <tabba@google.com>
Message-Id: <20231027182217.3615211-23-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-11-14 08:01:05 -05:00
Sean Christopherson
f128cf8cfb KVM: Convert KVM_ARCH_WANT_MMU_NOTIFIER to CONFIG_KVM_GENERIC_MMU_NOTIFIER
Convert KVM_ARCH_WANT_MMU_NOTIFIER into a Kconfig and select it where
appropriate to effectively maintain existing behavior.  Using a proper
Kconfig will simplify building more functionality on top of KVM's
mmu_notifier infrastructure.

Add a forward declaration of kvm_gfn_range to kvm_types.h so that
including arch/powerpc/include/asm/kvm_ppc.h's with CONFIG_KVM=n doesn't
generate warnings due to kvm_gfn_range being undeclared.  PPC defines
hooks for PR vs. HV without guarding them via #ifdeffery, e.g.

  bool (*unmap_gfn_range)(struct kvm *kvm, struct kvm_gfn_range *range);
  bool (*age_gfn)(struct kvm *kvm, struct kvm_gfn_range *range);
  bool (*test_age_gfn)(struct kvm *kvm, struct kvm_gfn_range *range);
  bool (*set_spte_gfn)(struct kvm *kvm, struct kvm_gfn_range *range);

Alternatively, PPC could forward declare kvm_gfn_range, but there's no
good reason not to define it in common KVM.

Acked-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fuad Tabba <tabba@google.com>
Tested-by: Fuad Tabba <tabba@google.com>
Message-Id: <20231027182217.3615211-8-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-11-13 05:29:09 -05:00
Sean Christopherson
4a2e993faa KVM: PPC: Return '1' unconditionally for KVM_CAP_SYNC_MMU
Advertise that KVM's MMU is synchronized with the primary MMU for all
flavors of PPC KVM support, i.e. advertise that the MMU is synchronized
when CONFIG_KVM_BOOK3S_HV_POSSIBLE=y but the VM is not using hypervisor
mode (a.k.a. PR VMs).  PR VMs, via kvm_unmap_gfn_range_pr(), do the right
thing for mmu_notifier invalidation events, and more tellingly, KVM
returns '1' for KVM_CAP_SYNC_MMU when CONFIG_KVM_BOOK3S_HV_POSSIBLE=n
and CONFIG_KVM_BOOK3S_PR_POSSIBLE=y, i.e. KVM already advertises a
synchronized MMU for PR VMs, just not when CONFIG_KVM_BOOK3S_HV_POSSIBLE=y.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20231027182217.3615211-7-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-11-13 05:29:09 -05:00