The original implementation of vq_present() relied on aggressive
inlining in order for the compiler to know that the code is
correct, due to some const-casting issues. This was causing sparse
and clang to complain, while GCC compiled cleanly.
Commit 0c529ff789bc addressed this problem, but since vq_present()
is no longer a function, there is now no implicit casting of the
returned value to the return type (bool).
In set_sve_vls(), this uncast bit value is compared against a bool,
and so may spuriously compare as unequal when both are nonzero. As
a result, KVM may reject valid SVE vector length configurations as
invalid, and vice versa.
Fix it by forcing the returned value to a bool.
Signed-off-by: Zhang Lei <zhang.lei@jp.fujitsu.com>
Fixes: 0c529ff789bc ("KVM: arm64: Implement vq_present() as a macro")
Signed-off-by: Dave Martin <Dave.Martin@arm.com> [commit message rewrite]
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Likely our final small batch of fixes for 5.2:
- Some fixes for USB on davinci, regressions were due to the recent
conversion of the OCHI driver to use GPIO regulators
- A fixup of kconfig dependencies for a TI irq controller
- A switch of armada-38x to avoid dropped characters on uart, caused by
switch of base inherited platform description earlier this year
-----BEGIN PGP SIGNATURE-----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=2Hcr
-----END PGP SIGNATURE-----
Merge tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc
Pull ARM SoC fixes from Olof Johansson:
"Likely our final small batch of fixes for 5.2:
- Some fixes for USB on davinci, regressions were due to the recent
conversion of the OCHI driver to use GPIO regulators
- A fixup of kconfig dependencies for a TI irq controller
- A switch of armada-38x to avoid dropped characters on uart, caused
by switch of base inherited platform description earlier this year"
* tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc:
ARM: davinci: da830-evm: fix GPIO lookup for OHCI
ARM: davinci: omapl138-hawk: add missing regulator constraints for OHCI
ARM: davinci: da830-evm: add missing regulator constraints for OHCI
soc: ti: fix irq-ti-sci link error
ARM: dts: armada-xp-98dx3236: Switch to armada-38x-uart serial node
Do not issue CLP_SET_ENABLE_MIO after opting out of MIO instruction
usage. This should not fix a bug but reduce overhead within firmware.
Signed-off-by: Sebastian Ott <sebott@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Unfortunately we have to handle a class of devices that don't support the
new MIO instructions. Adjust resource assignment and mapping accordingly.
Signed-off-by: Sebastian Ott <sebott@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
perf/core has an earlier version of the x86/cpu tree merged, to avoid
conflicts, and due to this we want to pick up this ABI impacting
revert as well:
049331f277fe: ("x86/fsgsbase: Revert FSGSBASE support")
Signed-off-by: Ingo Molnar <mingo@kernel.org>
- Fixes a deadlock from a previous fix to keep module loading
and function tracing text modifications from stepping on each other.
(this has a few patches to help document the issue in comments)
- Fix a crash when the snapshot buffer gets out of sync with the
main ring buffer.
- Fix a memory leak when reading the memory logs
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCXRzBCBQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qnDaAP9qTFBOFtgIGCT5wVP8xjQeESxh1b8R
tbaT7/U2oPpeiwEAvp1mYo5UYcc8KauBqVaLSLJVN4pv07xiZF5Qgh9C1QE=
=m2IT
-----END PGP SIGNATURE-----
Merge tag 'trace-v5.2-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
"This includes three fixes:
- Fix a deadlock from a previous fix to keep module loading and
function tracing text modifications from stepping on each other
(this has a few patches to help document the issue in comments)
- Fix a crash when the snapshot buffer gets out of sync with the main
ring buffer
- Fix a memory leak when reading the memory logs"
* tag 'trace-v5.2-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
ftrace/x86: Anotate text_mutex split between ftrace_arch_code_modify_post_process() and ftrace_arch_code_modify_prepare()
tracing/snapshot: Resize spare buffer if size changed
tracing: Fix memory leak in tracing_err_log_open()
ftrace/x86: Add a comment to why we take text_mutex in ftrace_arch_code_modify_prepare()
ftrace/x86: Remove possible deadlock between register_kprobe() and ftrace_run_update_code()
The FSGSBASE series turned out to have serious bugs and there is still an
open issue which is not fully understood yet.
The confidence in those changes has become close to zero especially as the
test cases which have been shipped with that series were obviously never
run before sending the final series out to LKML.
./fsgsbase_64 >/dev/null
Segmentation fault
As the merge window is close, the only sane decision is to revert FSGSBASE
support. The revert is necessary as this branch has been merged into
perf/core already and rebasing all of that a few days before the merge
window is not the most brilliant idea.
I could definitely slap myself for not noticing the test case fail when
merging that series, but TBH my expectations weren't that low back
then. Won't happen again.
Revert the following commits:
539bca535dec ("x86/entry/64: Fix and clean up paranoid_exit")
2c7b5ac5d5a9 ("Documentation/x86/64: Add documentation for GS/FS addressing mode")
f987c955c745 ("x86/elf: Enumerate kernel FSGSBASE capability in AT_HWCAP2")
2032f1f96ee0 ("x86/cpu: Enable FSGSBASE on 64bit by default and add a chicken bit")
5bf0cab60ee2 ("x86/entry/64: Document GSBASE handling in the paranoid path")
708078f65721 ("x86/entry/64: Handle FSGSBASE enabled paranoid entry/exit")
79e1932fa3ce ("x86/entry/64: Introduce the FIND_PERCPU_BASE macro")
1d07316b1363 ("x86/entry/64: Switch CR3 before SWAPGS in paranoid entry")
f60a83df4593 ("x86/process/64: Use FSGSBASE instructions on thread copy and ptrace")
1ab5f3f7fe3d ("x86/process/64: Use FSBSBASE in switch_to() if available")
a86b4625138d ("x86/fsgsbase/64: Enable FSGSBASE instructions in helper functions")
8b71340d702e ("x86/fsgsbase/64: Add intrinsics for FSGSBASE instructions")
b64ed19b93c3 ("x86/cpu: Add 'unsafe_fsgsbase' to enable CR4.FSGSBASE")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Chang S. Bae <chang.seok.bae@intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ravi Shankar <ravi.v.shankar@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
This implements 5-way interleaving for ECB, CBC decryption and CTR,
resulting in a speedup of ~11% on Marvell ThunderX2, which has a
very deep pipeline and therefore a high issue latency for NEON
instructions operating on the same registers.
Note that XTS is left alone: implementing 5-way interleave there
would either involve spilling of the calculated tweaks to the
stack, or recalculating them after the encryption operation, and
doing either of those would most likely penalize low end cores.
For ECB, this is not a concern at all, given that we have plenty
of spare registers. For CTR and CBC decryption, we take advantage
of the fact that v16 is not used by the CE version of the code
(which is the only one targeted by the optimization), and so we
can reshuffle the code a bit and avoid having to spill to memory
(with the exception of one extra reload in the CBC routine)
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
In preparation of tweaking the accelerated AES chaining mode routines
to be able to use a 5-way stride, implement the core routines to
support processing 5 blocks of input at a time. While at it, drop
the 2 way versions, which have been unused for a while now.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Hyper-V clock/timer code and data structures are currently mixed
in with other code in the ISA independent drivers/hv directory as
well as the ISA dependent Hyper-V code under arch/x86.
Consolidate this code and data structures into a Hyper-V clocksource driver
to better follow the Linux model. In doing so, separate out the ISA
dependent portions so the new clocksource driver works for x86 and for the
in-process Hyper-V on ARM64 code.
To start, move the existing clockevents code to create the new clocksource
driver. Update the VMbus driver to call initialization and cleanup routines
since the Hyper-V synthetic timers are not independently enumerated in
ACPI.
No behavior is changed and no new functionality is added.
Suggested-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: "bp@alien8.de" <bp@alien8.de>
Cc: "will.deacon@arm.com" <will.deacon@arm.com>
Cc: "catalin.marinas@arm.com" <catalin.marinas@arm.com>
Cc: "mark.rutland@arm.com" <mark.rutland@arm.com>
Cc: "linux-arm-kernel@lists.infradead.org" <linux-arm-kernel@lists.infradead.org>
Cc: "gregkh@linuxfoundation.org" <gregkh@linuxfoundation.org>
Cc: "linux-hyperv@vger.kernel.org" <linux-hyperv@vger.kernel.org>
Cc: "olaf@aepfle.de" <olaf@aepfle.de>
Cc: "apw@canonical.com" <apw@canonical.com>
Cc: "jasowang@redhat.com" <jasowang@redhat.com>
Cc: "marcelo.cerri@canonical.com" <marcelo.cerri@canonical.com>
Cc: Sunil Muthuswamy <sunilmut@microsoft.com>
Cc: KY Srinivasan <kys@microsoft.com>
Cc: "sashal@kernel.org" <sashal@kernel.org>
Cc: "vincenzo.frascino@arm.com" <vincenzo.frascino@arm.com>
Cc: "linux-arch@vger.kernel.org" <linux-arch@vger.kernel.org>
Cc: "linux-mips@vger.kernel.org" <linux-mips@vger.kernel.org>
Cc: "linux-kselftest@vger.kernel.org" <linux-kselftest@vger.kernel.org>
Cc: "arnd@arndb.de" <arnd@arndb.de>
Cc: "linux@armlinux.org.uk" <linux@armlinux.org.uk>
Cc: "ralf@linux-mips.org" <ralf@linux-mips.org>
Cc: "paul.burton@mips.com" <paul.burton@mips.com>
Cc: "daniel.lezcano@linaro.org" <daniel.lezcano@linaro.org>
Cc: "salyzyn@android.com" <salyzyn@android.com>
Cc: "pcc@google.com" <pcc@google.com>
Cc: "shuah@kernel.org" <shuah@kernel.org>
Cc: "0x7f454c46@gmail.com" <0x7f454c46@gmail.com>
Cc: "linux@rasmusvillemoes.dk" <linux@rasmusvillemoes.dk>
Cc: "huw@codeweavers.com" <huw@codeweavers.com>
Cc: "sfr@canb.auug.org.au" <sfr@canb.auug.org.au>
Cc: "pbonzini@redhat.com" <pbonzini@redhat.com>
Cc: "rkrcmar@redhat.com" <rkrcmar@redhat.com>
Cc: "kvm@vger.kernel.org" <kvm@vger.kernel.org>
Link: https://lkml.kernel.org/r/1561955054-1838-2-git-send-email-mikelley@microsoft.com
Quite some time ago the interrupt entry stubs for unused vectors in the
system vector range got removed and directly mapped to the spurious
interrupt vector entry point.
Sounds reasonable, but it's subtly broken. The spurious interrupt vector
entry point pushes vector number 0xFF on the stack which makes the whole
logic in __smp_spurious_interrupt() pointless.
As a consequence any spurious interrupt which comes from a vector != 0xFF
is treated as a real spurious interrupt (vector 0xFF) and not
acknowledged. That subsequently stalls all interrupt vectors of equal and
lower priority, which brings the system to a grinding halt.
This can happen because even on 64-bit the system vector space is not
guaranteed to be fully populated. A full compile time handling of the
unused vectors is not possible because quite some of them are conditonally
populated at runtime.
Bring the entry stubs back, which wastes 160 bytes if all stubs are unused,
but gains the proper handling back. There is no point to selectively spare
some of the stubs which are known at compile time as the required code in
the IDT management would be way larger and convoluted.
Do not route the spurious entries through common_interrupt and do_IRQ() as
the original code did. Route it to smp_spurious_interrupt() which evaluates
the vector number and acts accordingly now that the real vector numbers are
handed in.
Fixup the pr_warn so the actual spurious vector (0xff) is clearly
distiguished from the other vectors and also note for the vectored case
whether it was pending in the ISR or not.
"Spurious APIC interrupt (vector 0xFF) on CPU#0, should never happen."
"Spurious interrupt vector 0xed on CPU#1. Acked."
"Spurious interrupt vector 0xee on CPU#1. Not pending!."
Fixes: 2414e021ac8d ("x86: Avoid building unused IRQ entry stubs")
Reported-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Jan Beulich <jbeulich@suse.com>
Link: https://lkml.kernel.org/r/20190628111440.550568228@linutronix.de
Since the rework of the vector management, warnings about spurious
interrupts have been reported. Robert provided some more information and
did an initial analysis. The following situation leads to these warnings:
CPU 0 CPU 1 IO_APIC
interrupt is raised
sent to CPU1
Unable to handle
immediately
(interrupts off,
deep idle delay)
mask()
...
free()
shutdown()
synchronize_irq()
clear_vector()
do_IRQ()
-> vector is clear
Before the rework the vector entries of legacy interrupts were statically
assigned and occupied precious vector space while most of them were
unused. Due to that the above situation was handled silently because the
vector was handled and the core handler of the assigned interrupt
descriptor noticed that it is shut down and returned.
While this has been usually observed with legacy interrupts, this situation
is not limited to them. Any other interrupt source, e.g. MSI, can cause the
same issue.
After adding proper synchronization for level triggered interrupts, this
can only happen for edge triggered interrupts where the IO-APIC obviously
cannot provide information about interrupts in flight.
While the spurious warning is actually harmless in this case it worries
users and driver developers.
Handle it gracefully by marking the vector entry as VECTOR_SHUTDOWN instead
of VECTOR_UNUSED when the vector is freed up.
If that above late handling happens the spurious detector will not complain
and switch the entry to VECTOR_UNUSED. Any subsequent spurious interrupt on
that line will trigger the spurious warning as before.
Fixes: 464d12309e1b ("x86/vector: Switch IOAPIC to global reservation mode")
Reported-by: Robert Hodaszi <Robert.Hodaszi@digi.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>-
Tested-by: Robert Hodaszi <Robert.Hodaszi@digi.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Link: https://lkml.kernel.org/r/20190628111440.459647741@linutronix.de
When an interrupt is shut down in free_irq() there might be an inflight
interrupt pending in the IO-APIC remote IRR which is not yet serviced. That
means the interrupt has been sent to the target CPUs local APIC, but the
target CPU is in a state which delays the servicing.
So free_irq() would proceed to free resources and to clear the vector
because synchronize_hardirq() does not see an interrupt handler in
progress.
That can trigger a spurious interrupt warning, which is harmless and just
confuses users, but it also can leave the remote IRR in a stale state
because once the handler is invoked the interrupt resources might be freed
already and therefore acknowledgement is not possible anymore.
Implement the irq_get_irqchip_state() callback for the IO-APIC irq chip. The
callback is invoked from free_irq() via __synchronize_hardirq(). Check the
remote IRR bit of the interrupt and return 'in flight' if it is set and the
interrupt is configured in level mode. For edge mode the remote IRR has no
meaning.
As this is only meaningful for level triggered interrupts this won't cure
the potential spurious interrupt warning for edge triggered interrupts, but
the edge trigger case does not result in stale hardware state. This has to
be addressed at the vector/interrupt entry level seperately.
Fixes: 464d12309e1b ("x86/vector: Switch IOAPIC to global reservation mode")
Reported-by: Robert Hodaszi <Robert.Hodaszi@digi.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Link: https://lkml.kernel.org/r/20190628111440.370295517@linutronix.de
- Fix module allocation when running with KASLR enabled
- Fix broken build due to bug in LLVM linker (ld.lld)
-----BEGIN PGP SIGNATURE-----
iQEzBAABCgAdFiEEPxTL6PPUbjXGY88ct6xw3ITBYzQFAl0Z9bIACgkQt6xw3ITB
YzS70gf/Trw6+Yy1dHSyz5f2W9OtedFFv+rEGcvUkF6kYFffw7taNj30K6otjkK7
CYPp9kWYpFhGgE7VwAfQ9NGyAwZ62IvGhQDYdAG72Y39zX7yQ4OHWKdr8K53KYN8
CThcgXxEPoZw1pP7fwXkaBiiljW6JGF64Hv3ybA1vzGmjiv6wdjO3pQlbXkJu4kk
xlsLSLOZUDawcRuVNGWwPiToxopVTcAJ3lapYBVmO2dSO00QYv1jvJgV0tK6n68q
ZQMJbTdNHLIKMRdLcDBGQAwetWkkZ5LazwuiaHQcSQcRgp7IkKrIvEz8vzkdAvcR
jniDc7bbKYlvlJdiquIOH2l1ElEQyQ==
=Pp2j
-----END PGP SIGNATURE-----
Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 fixes from Will Deacon:
"Fix a build failure with the LLVM linker and a module allocation
failure when KASLR is active:
- Fix module allocation when running with KASLR enabled
- Fix broken build due to bug in LLVM linker (ld.lld)"
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64/efi: Mark __efistub_stext_offset as an absolute symbol explicitly
arm64: kaslr: keep modules inside module region when KASAN is enabled
OHCI driver was converted over to use GPIO regulators.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1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=vwpF
-----END PGP SIGNATURE-----
Merge tag 'davinci-fixes-for-v5.2-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/nsekhar/linux-davinci into arm/fixes
This set of patches fixes regressions introduced in v5.2 kernel when DA8xx
OHCI driver was converted over to use GPIO regulators.
* tag 'davinci-fixes-for-v5.2-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/nsekhar/linux-davinci:
ARM: davinci: da830-evm: fix GPIO lookup for OHCI
ARM: davinci: omapl138-hawk: add missing regulator constraints for OHCI
ARM: davinci: da830-evm: add missing regulator constraints for OHCI
+ Linux 5.2-rc7
Signed-off-by: Olof Johansson <olof@lixom.net>
ftrace_arch_code_modify_prepare() is acquiring text_mutex, while the
corresponding release is happening in ftrace_arch_code_modify_post_process().
This has already been documented in the code, but let's also make the fact
that this is intentional clear to the semantic analysis tools such as sparse.
Link: http://lkml.kernel.org/r/nycvar.YFH.7.76.1906292321170.27227@cbobk.fhfr.pm
Fixes: 39611265edc1a ("ftrace/x86: Add a comment to why we take text_mutex in ftrace_arch_code_modify_prepare()")
Fixes: d5b844a2cf507 ("ftrace/x86: Remove possible deadlock between register_kprobe() and ftrace_run_update_code()")
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Thomas reported that:
| Background:
|
| In preparation of supporting IPI shorthands I changed the CPU offline
| code to software disable the local APIC instead of just masking it.
| That's done by clearing the APIC_SPIV_APIC_ENABLED bit in the APIC_SPIV
| register.
|
| Failure:
|
| When the CPU comes back online the startup code triggers occasionally
| the warning in apic_pending_intr_clear(). That complains that the IRRs
| are not empty.
|
| The offending vector is the local APIC timer vector who's IRR bit is set
| and stays set.
|
| It took me quite some time to reproduce the issue locally, but now I can
| see what happens.
|
| It requires apicv_enabled=0, i.e. full apic emulation. With apicv_enabled=1
| (and hardware support) it behaves correctly.
|
| Here is the series of events:
|
| Guest CPU
|
| goes down
|
| native_cpu_disable()
|
| apic_soft_disable();
|
| play_dead()
|
| ....
|
| startup()
|
| if (apic_enabled())
| apic_pending_intr_clear() <- Not taken
|
| enable APIC
|
| apic_pending_intr_clear() <- Triggers warning because IRR is stale
|
| When this happens then the deadline timer or the regular APIC timer -
| happens with both, has fired shortly before the APIC is disabled, but the
| interrupt was not serviced because the guest CPU was in an interrupt
| disabled region at that point.
|
| The state of the timer vector ISR/IRR bits:
|
| ISR IRR
| before apic_soft_disable() 0 1
| after apic_soft_disable() 0 1
|
| On startup 0 1
|
| Now one would assume that the IRR is cleared after the INIT reset, but this
| happens only on CPU0.
|
| Why?
|
| Because our CPU0 hotplug is just for testing to make sure nothing breaks
| and goes through an NMI wakeup vehicle because INIT would send it through
| the boots-trap code which is not really working if that CPU was not
| physically unplugged.
|
| Now looking at a real world APIC the situation in that case is:
|
| ISR IRR
| before apic_soft_disable() 0 1
| after apic_soft_disable() 0 1
|
| On startup 0 0
|
| Why?
|
| Once the dying CPU reenables interrupts the pending interrupt gets
| delivered as a spurious interupt and then the state is clear.
|
| While that CPU0 hotplug test case is surely an esoteric issue, the APIC
| emulation is still wrong, Even if the play_dead() code would not enable
| interrupts then the pending IRR bit would turn into an ISR .. interrupt
| when the APIC is reenabled on startup.
From SDM 10.4.7.2 Local APIC State After It Has Been Software Disabled
* Pending interrupts in the IRR and ISR registers are held and require
masking or handling by the CPU.
In Thomas's testing, hardware cpu will not respect soft disable LAPIC
when IRR has already been set or APICv posted-interrupt is in flight,
so we can skip soft disable APIC checking when clearing IRR and set ISR,
continue to respect soft disable APIC when attempting to set IRR.
Reported-by: Rong Chen <rong.a.chen@intel.com>
Reported-by: Feng Tang <feng.tang@intel.com>
Reported-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Rong Chen <rong.a.chen@intel.com>
Cc: Feng Tang <feng.tang@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Currently KVM_STATE_NESTED_EVMCS is used to signal that eVMCS
capability is enabled on vCPU.
As indicated by vmx->nested.enlightened_vmcs_enabled.
This is quite bizarre as userspace VMM should make sure to expose
same vCPU with same CPUID values in both source and destination.
In case vCPU is exposed with eVMCS support on CPUID, it is also
expected to enable KVM_CAP_HYPERV_ENLIGHTENED_VMCS capability.
Therefore, KVM_STATE_NESTED_EVMCS is redundant.
KVM_STATE_NESTED_EVMCS is currently used on restore path
(vmx_set_nested_state()) only to enable eVMCS capability in KVM
and to signal need_vmcs12_sync such that on next VMEntry to guest
nested_sync_from_vmcs12() will be called to sync vmcs12 content
into eVMCS in guest memory.
However, because restore nested-state is rare enough, we could
have just modified vmx_set_nested_state() to always signal
need_vmcs12_sync.
From all the above, it seems that we could have just removed
the usage of KVM_STATE_NESTED_EVMCS. However, in order to preserve
backwards migration compatibility, we cannot do that.
(vmx_get_nested_state() needs to signal flag when migrating from
new kernel to old kernel).
Returning KVM_STATE_NESTED_EVMCS when just vCPU have eVMCS enabled
have a bad side-effect of userspace VMM having to send nested-state
from source to destination as part of migration stream. Even if
guest have never used eVMCS as it doesn't even run a nested
hypervisor workload. This requires destination userspace VMM and
KVM to support setting nested-state. Which make it more difficult
to migrate from new host to older host.
To avoid this, change KVM_STATE_NESTED_EVMCS to signal eVMCS is
not only enabled but also active. i.e. Guest have made some
eVMCS active via an enlightened VMEntry. i.e. vmcs12 is copied
from eVMCS and therefore should be restored into eVMCS resident
in memory (by copy_vmcs12_to_enlightened()).
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Maran Wilson <maran.wilson@oracle.com>
Reviewed-by: Krish Sadhukhan <krish.sadhukhan@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
As comment in code specifies, SMM temporarily disables VMX so we cannot
be in guest mode, nor can VMLAUNCH/VMRESUME be pending.
However, code currently assumes that these are the only flags that can be
set on kvm_state->flags. This is not true as KVM_STATE_NESTED_EVMCS
can also be set on this field to signal that eVMCS should be enabled.
Therefore, fix code to check for guest-mode and pending VMLAUNCH/VMRESUME
explicitly.
Reviewed-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This warning can be triggered easily by userspace, so it should certainly not
cause a panic if panic_on_warn is set.
Reported-by: syzbot+c03f30b4f4c46bdf8575@syzkaller.appspotmail.com
Suggested-by: Alexander Potapenko <glider@google.com>
Acked-by: Alexander Potapenko <glider@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The fixed regulator driver doesn't specify any con_id for gpio lookup
so it must be NULL in the table entry.
Fixes: 274e4c336192 ("ARM: davinci: da830-evm: add a fixed regulator for ohci-da8xx")
Cc: stable@vger.kernel.org
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
We need to enable status changes for the fixed power supply for the USB
controller.
Fixes: 1d272894ec4f ("ARM: davinci: omapl138-hawk: add a fixed regulator for ohci-da8xx")
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
We need to enable status changes for the fixed power supply for the USB
controller.
Fixes: 274e4c336192 ("ARM: davinci: da830-evm: add a fixed regulator for ohci-da8xx")
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
AP Queue Interruption Control (AQIC) facility gives
the guest the possibility to control interruption for
the Cryptographic Adjunct Processor queues.
Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: Tony Krowiak <akrowiak@linux.ibm.com>
Acked-by: Harald Freudenberger <freude@linux.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
[ Modified while picking: we may not expose STFLE facility 65
unconditionally because AIV is a pre-requirement.]
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
We prepare the interception of the PQAP/AQIC instruction for
the case the AQIC facility is enabled in the guest.
First of all we do not want to change existing behavior when
intercepting AP instructions without the SIE allowing the guest
to use AP instructions.
In this patch we only handle the AQIC interception allowed by
facility 65 which will be enabled when the complete interception
infrastructure will be present.
We add a callback inside the KVM arch structure for s390 for
a VFIO driver to handle a specific response to the PQAP
instruction with the AQIC command and only this command.
But we want to be able to return a correct answer to the guest
even there is no VFIO AP driver in the kernel.
Therefor, we inject the correct exceptions from inside KVM for the
case the callback is not initialized, which happens when the vfio_ap
driver is not loaded.
We do consider the responsibility of the driver to always initialize
the PQAP callback if it defines queues by initializing the CRYCB for
a guest.
If the callback has been setup we call it.
If not we setup an answer considering that no queue is available
for the guest when no callback has been setup.
Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: Tony Krowiak <akrowiak@linux.ibm.com>
Acked-by: Harald Freudenberger <freude@linux.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Kasan instrumentation of backchain unwinder stack reads is disabled
completely and simply uses READ_ONCE_NOCHECK now.
READ_ONCE_TASK_STACK macro is unused and could be removed.
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Avoid kasan false positive when current task is interrupted in-between
stack frame allocation and backchain write instructions leaving new stack
frame backchain invalid. In particular if backchain is 0 the unwinder
tries to read pt_regs from the stack and might hit kasan poisoned bytes,
leading to kasan "stack-out-of-bounds" report.
Disable kasan instrumentation of unwinder stack reads, since this
limitation couldn't be handled otherwise with current backchain unwinder
implementation.
Fixes: 78c98f907413 ("s390/unwind: introduce stack unwind API")
Reported-by: Julian Wiedmann <jwi@linux.ibm.com>
Tested-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
paranoid_exit needs to restore CR3 before GSBASE. Doing it in the opposite
order crashes if the exception came from a context with user GSBASE and
user CR3 -- RESTORE_CR3 cannot resture user CR3 if run with user GSBASE.
This results in infinitely recursing exceptions if user code does SYSENTER
with TF set if both FSGSBASE and PTI are enabled.
The old code worked if user code just set TF without SYSENTER because #DB
from user mode is special cased in idtentry and paranoid_exit doesn't run.
Fix it by cleaning up the spaghetti code. All that paranoid_exit needs to
do is to disable IRQs, handle IRQ tracing, then restore CR3, and restore
GSBASE. Simply do those actions in that order.
Fixes: 708078f65721 ("x86/entry/64: Handle FSGSBASE enabled paranoid entry/exit")
Reported-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ravi Shankar <ravi.v.shankar@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Link: https://lkml.kernel.org/r/59725ceb08977359489fbed979716949ad45f616.1562035429.git.luto@kernel.org
It's only used if !CONFIG_IA32_EMULATION, so disable it in normal
configs. This will save a few bytes of text and reduce confusion.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: "BaeChang Seok" <chang.seok.bae@intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: "Bae, Chang Seok" <chang.seok.bae@intel.com>
Link: https://lkml.kernel.org/r/0f7dafa72fe7194689de5ee8cfe5d83509fabcf5.1562035429.git.luto@kernel.org
Use the armada-38x-uart compatible strings for Armada XP 98dx3236 SoCs
in order to not loose character anymore.
-----BEGIN PGP SIGNATURE-----
iF0EABECAB0WIQQYqXDMF3cvSLY+g9cLBhiOFHI71QUCXRYouQAKCRALBhiOFHI7
1XlVAJ0Qjg4gFXUrf7MUpn8LuUi6UTEf3ACdGLW5ZT78BM78TiEGG79H+WsJ/ow=
=jxUU
-----END PGP SIGNATURE-----
Merge tag 'mvebu-fixes-5.2-2' of git://git.infradead.org/linux-mvebu into arm/fixes
mvebu fixes for 5.2 (part 2)
Use the armada-38x-uart compatible strings for Armada XP 98dx3236 SoCs
in order to not loose character anymore.
* tag 'mvebu-fixes-5.2-2' of git://git.infradead.org/linux-mvebu:
ARM: dts: armada-xp-98dx3236: Switch to armada-38x-uart serial node
Signed-off-by: Olof Johansson <olof@lixom.net>
When we remap memory as non-cached, to be used as a DMA coherent buffer,
we should writeback all cache and invalidate the cache lines so that we
make sure we have a clean slate. Implement this using the cache_push()
helper.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
This switches m68k to using common code for the DMA allocations,
including potential use of the CMA allocator if configured.
Also add a comment where the existing behavior seems to be lacking.
Switching to the generic code enables DMA allocations from atomic
context, which is required by the DMA API documentation, and also
adds various other minor features drivers start relying upon. It
also makes sure we have a tested code base for all architectures
that require uncached pte bits for coherent DMA allocations.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
One fix for a regression in my commit adding KUAP (Kernel User Access
Prevention) on Radix, which incorrectly touched the AMR in the early machine
check handler.
Thanks to:
Nicholas Piggin.
-----BEGIN PGP SIGNATURE-----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=I22i
-----END PGP SIGNATURE-----
Merge tag 'powerpc-5.2-7' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fix from Michael Ellerman:
"One fix for a regression in my commit adding KUAP (Kernel User Access
Prevention) on Radix, which incorrectly touched the AMR in the early
machine check handler.
Thanks to Nicholas Piggin"
* tag 'powerpc-5.2-7' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/64s/exception: Fix machine check early corrupting AMR
Pull x86 fixes from Ingo Molnar:
"Misc fixes all over the place:
- might_sleep() atomicity fix in the microcode loader
- resctrl boundary condition fix
- APIC arithmethics bug fix for frequencies >= 4.2 GHz
- three 5-level paging crash fixes
- two speculation fixes
- a perf/stacktrace fix"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/unwind/orc: Fall back to using frame pointers for generated code
perf/x86: Always store regs->ip in perf_callchain_kernel()
x86/speculation: Allow guests to use SSBD even if host does not
x86/mm: Handle physical-virtual alignment mismatch in phys_p4d_init()
x86/boot/64: Add missing fixup_pointer() for next_early_pgt access
x86/boot/64: Fix crash if kernel image crosses page table boundary
x86/apic: Fix integer overflow on 10 bit left shift of cpu_khz
x86/resctrl: Prevent possible overrun during bitmap operations
x86/microcode: Fix the microcode load on CPU hotplug for real
Pull perf fixes from Ingo Molnar:
"Various fixes, most of them related to bugs perf fuzzing found in the
x86 code"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/regs: Use PERF_REG_EXTENDED_MASK
perf/x86: Remove pmu->pebs_no_xmm_regs
perf/x86: Clean up PEBS_XMM_REGS
perf/x86/regs: Check reserved bits
perf/x86: Disable extended registers for non-supported PMUs
perf/ioctl: Add check for the sample_period value
perf/core: Fix perf_sample_regs_user() mm check
Pull irq fixes from Ingo Molnar:
"Diverse irqchip driver fixes"
* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irqchip/gic-v3-its: Fix command queue pointer comparison bug
irqchip/mips-gic: Use the correct local interrupt map registers
irqchip/ti-sci-inta: Fix kernel crash if irq_create_fwspec_mapping fail
irqchip/irq-csky-mpintc: Support auto irq deliver to all cpus
Pull EFI fixes from Ingo Molnar:
"Four fixes:
- fix a kexec crash on arm64
- fix a reboot crash on some Android platforms
- future-proof the code for upcoming ACPI 6.2 changes
- fix a build warning on x86"
* 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
efibc: Replace variable set function in notifier call
x86/efi: fix a -Wtype-limits compilation warning
efi/bgrt: Drop BGRT status field reserved bits check
efi/memreserve: deal with memreserve entries in unmapped memory
Recent Intel chipsets including Skylake and ApolloLake have a special
ITSSPRC register which allows the 8254 PIT to be gated. When gated, the
8254 registers can still be programmed as normal, but there are no IRQ0
timer interrupts.
Some products such as the Connex L1430 and exone go Rugged E11 use this
register to ship with the PIT gated by default. This causes Linux to fail
to boot:
Kernel panic - not syncing: IO-APIC + timer doesn't work! Boot with
apic=debug and send a report.
The panic happens before the framebuffer is initialized, so to the user, it
appears as an early boot hang on a black screen.
Affected products typically have a BIOS option that can be used to enable
the 8254 and make Linux work (Chipset -> South Cluster Configuration ->
Miscellaneous Configuration -> 8254 Clock Gating), however it would be best
to make Linux support the no-8254 case.
Modern sytems allow to discover the TSC and local APIC timer frequencies,
so the calibration against the PIT is not required. These systems have
always running timers and the local APIC timer works also in deep power
states.
So the setup of the PIT including the IO-APIC timer interrupt delivery
checks are a pointless exercise.
Skip the PIT setup and the IO-APIC timer interrupt checks on these systems,
which avoids the panic caused by non ticking PITs and also speeds up the
boot process.
Thanks to Daniel for providing the changelog, initial analysis of the
problem and testing against a variety of machines.
Reported-by: Daniel Drake <drake@endlessm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Daniel Drake <drake@endlessm.com>
Cc: bp@alien8.de
Cc: hpa@zytor.com
Cc: linux@endlessm.com
Cc: rafael.j.wysocki@intel.com
Cc: hdegoede@redhat.com
Link: https://lkml.kernel.org/r/20190628072307.24678-1-drake@endlessm.com
The fixes have no functional impact:
- Fix some comment text in the memory management vmalloc_fault path.
- Fix some warnings from the DT compiler in our newly-added DT files.
- Change the newly-added DT bindings such that SoC IP blocks with
external I/O are marked as "disabled" by default, then enable them
explicitly in board DT files when the devices are used on the board.
This aligns the bindings with existing upstream practice.
- Add the MIT license as an option for a minor header file, at the
request of one of the U-Boot maintainers.
The RISC-V defconfig update builds the SiFive SPI driver and the
MMC-SPI driver by default. The intention here is to make v5.2 more
usable for testers and users with RISC-V hardware.
-----BEGIN PGP SIGNATURE-----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=+HL9
-----END PGP SIGNATURE-----
Merge tag 'riscv-for-v5.2/fixes-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
Pull RISC-V fixes from Paul Walmsley:
"Minor RISC-V fixes and one defconfig update.
The fixes have no functional impact:
- Fix some comment text in the memory management vmalloc_fault path.
- Fix some warnings from the DT compiler in our newly-added DT files.
- Change the newly-added DT bindings such that SoC IP blocks with
external I/O are marked as "disabled" by default, then enable them
explicitly in board DT files when the devices are used on the
board. This aligns the bindings with existing upstream practice.
- Add the MIT license as an option for a minor header file, at the
request of one of the U-Boot maintainers.
The RISC-V defconfig update builds the SiFive SPI driver and the
MMC-SPI driver by default. The intention here is to make v5.2 more
usable for testers and users with RISC-V hardware"
* tag 'riscv-for-v5.2/fixes-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
riscv: mm: Fix code comment
dt-bindings: clock: sifive: add MIT license as an option for the header file
dt-bindings: riscv: resolve 'make dt_binding_check' warnings
riscv: dts: Re-organize the DT nodes
RISC-V: defconfig: enable MMC & SPI for RISC-V
Taking the text_mutex in ftrace_arch_code_modify_prepare() is to fix a
race against module loading and live kernel patching that might try to
change the text permissions while ftrace has it as read/write. This
really needs to be documented in the code. Add a comment that does such.
Link: http://lkml.kernel.org/r/20190627211819.5a591f52@gandalf.local.home
Suggested-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The commit 9f255b632bf12c4dd7 ("module: Fix livepatch/ftrace module text
permissions race") causes a possible deadlock between register_kprobe()
and ftrace_run_update_code() when ftrace is using stop_machine().
The existing dependency chain (in reverse order) is:
-> #1 (text_mutex){+.+.}:
validate_chain.isra.21+0xb32/0xd70
__lock_acquire+0x4b8/0x928
lock_acquire+0x102/0x230
__mutex_lock+0x88/0x908
mutex_lock_nested+0x32/0x40
register_kprobe+0x254/0x658
init_kprobes+0x11a/0x168
do_one_initcall+0x70/0x318
kernel_init_freeable+0x456/0x508
kernel_init+0x22/0x150
ret_from_fork+0x30/0x34
kernel_thread_starter+0x0/0xc
-> #0 (cpu_hotplug_lock.rw_sem){++++}:
check_prev_add+0x90c/0xde0
validate_chain.isra.21+0xb32/0xd70
__lock_acquire+0x4b8/0x928
lock_acquire+0x102/0x230
cpus_read_lock+0x62/0xd0
stop_machine+0x2e/0x60
arch_ftrace_update_code+0x2e/0x40
ftrace_run_update_code+0x40/0xa0
ftrace_startup+0xb2/0x168
register_ftrace_function+0x64/0x88
klp_patch_object+0x1a2/0x290
klp_enable_patch+0x554/0x980
do_one_initcall+0x70/0x318
do_init_module+0x6e/0x250
load_module+0x1782/0x1990
__s390x_sys_finit_module+0xaa/0xf0
system_call+0xd8/0x2d0
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(text_mutex);
lock(cpu_hotplug_lock.rw_sem);
lock(text_mutex);
lock(cpu_hotplug_lock.rw_sem);
It is similar problem that has been solved by the commit 2d1e38f56622b9b
("kprobes: Cure hotplug lock ordering issues"). Many locks are involved.
To be on the safe side, text_mutex must become a low level lock taken
after cpu_hotplug_lock.rw_sem.
This can't be achieved easily with the current ftrace design.
For example, arm calls set_all_modules_text_rw() already in
ftrace_arch_code_modify_prepare(), see arch/arm/kernel/ftrace.c.
This functions is called:
+ outside stop_machine() from ftrace_run_update_code()
+ without stop_machine() from ftrace_module_enable()
Fortunately, the problematic fix is needed only on x86_64. It is
the only architecture that calls set_all_modules_text_rw()
in ftrace path and supports livepatching at the same time.
Therefore it is enough to move text_mutex handling from the generic
kernel/trace/ftrace.c into arch/x86/kernel/ftrace.c:
ftrace_arch_code_modify_prepare()
ftrace_arch_code_modify_post_process()
This patch basically reverts the ftrace part of the problematic
commit 9f255b632bf12c4dd7 ("module: Fix livepatch/ftrace module
text permissions race"). And provides x86_64 specific-fix.
Some refactoring of the ftrace code will be needed when livepatching
is implemented for arm or nds32. These architectures call
set_all_modules_text_rw() and use stop_machine() at the same time.
Link: http://lkml.kernel.org/r/20190627081334.12793-1-pmladek@suse.com
Fixes: 9f255b632bf12c4dd7 ("module: Fix livepatch/ftrace module text permissions race")
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Reported-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
[
As reviewed by Miroslav Benes <mbenes@suse.cz>, removed return value of
ftrace_run_update_code() as it is a void function.
]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Programming MTRR registers in multi-processor systems is a rather lengthy
process. Furthermore, all processors must program these registers in lock
step and with interrupts disabled; the process also involves flushing
caches and TLBs twice. As a result, the process may take a considerable
amount of time.
On some platforms, this can lead to a large skew of the refined-jiffies
clock source. Early when booting, if no other clock is available (e.g.,
booting with hpet=disabled), the refined-jiffies clock source is used to
monitor the TSC clock source. If the skew of refined-jiffies is too large,
Linux wrongly assumes that the TSC is unstable:
clocksource: timekeeping watchdog on CPU1: Marking clocksource
'tsc-early' as unstable because the skew is too large:
clocksource: 'refined-jiffies' wd_now: fffedc10 wd_last:
fffedb90 mask: ffffffff
clocksource: 'tsc-early' cs_now: 5eccfddebc cs_last: 5e7e3303d4
mask: ffffffffffffffff
tsc: Marking TSC unstable due to clocksource watchdog
As per measurements, around 98% of the time needed by the procedure to
program MTRRs in multi-processor systems is spent flushing caches with
wbinvd(). As per the Section 11.11.8 of the Intel 64 and IA 32
Architectures Software Developer's Manual, it is not necessary to flush
caches if the CPU supports cache self-snooping. Thus, skipping the cache
flushes can reduce by several tens of milliseconds the time needed to
complete the programming of the MTRR registers:
Platform Before After
104-core (208 Threads) Skylake 1437ms 28ms
2-core ( 4 Threads) Haswell 114ms 2ms
Reported-by: Mohammad Etemadi <mohammad.etemadi@intel.com>
Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Alan Cox <alan.cox@intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Andi Kleen <andi.kleen@intel.com>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jordan Borgner <mail@jordan-borgner.de>
Cc: "Ravi V. Shankar" <ravi.v.shankar@intel.com>
Cc: Ricardo Neri <ricardo.neri@intel.com>
Cc: Andy Shevchenko <andriy.shevchenko@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Peter Feiner <pfeiner@google.com>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Link: https://lkml.kernel.org/r/1561689337-19390-3-git-send-email-ricardo.neri-calderon@linux.intel.com
Processors which have self-snooping capability can handle conflicting
memory type across CPUs by snooping its own cache. However, there exists
CPU models in which having conflicting memory types still leads to
unpredictable behavior, machine check errors, or hangs.
Clear this feature on affected CPUs to prevent its use.
Suggested-by: Alan Cox <alan.cox@intel.com>
Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Andi Kleen <andi.kleen@intel.com>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jordan Borgner <mail@jordan-borgner.de>
Cc: "Ravi V. Shankar" <ravi.v.shankar@intel.com>
Cc: Mohammad Etemadi <mohammad.etemadi@intel.com>
Cc: Ricardo Neri <ricardo.neri@intel.com>
Cc: Andy Shevchenko <andriy.shevchenko@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Peter Feiner <pfeiner@google.com>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Link: https://lkml.kernel.org/r/1561689337-19390-2-git-send-email-ricardo.neri-calderon@linux.intel.com
