The number reported by the query is N-1 and I think people reading the
sysfs file would expect N instead. For users creating VMs there's no
actual difference because KVM's limit is currently below the UV's
limit.
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Fixes: a0f60f8431999 ("s390/protvirt: Add sysfs firmware interface for Ultravisor information")
Cc: stable@vger.kernel.org
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
This implements the missing mount_setattr() syscall. While the new mount
api allows to change the properties of a superblock there is currently
no way to change the properties of a mount or a mount tree using file
descriptors which the new mount api is based on. In addition the old
mount api has the restriction that mount options cannot be applied
recursively. This hasn't changed since changing mount options on a
per-mount basis was implemented in [1] and has been a frequent request
not just for convenience but also for security reasons. The legacy
mount syscall is unable to accommodate this behavior without introducing
a whole new set of flags because MS_REC | MS_REMOUNT | MS_BIND |
MS_RDONLY | MS_NOEXEC | [...] only apply the mount option to the topmost
mount. Changing MS_REC to apply to the whole mount tree would mean
introducing a significant uapi change and would likely cause significant
regressions.
The new mount_setattr() syscall allows to recursively clear and set
mount options in one shot. Multiple calls to change mount options
requesting the same changes are idempotent:
int mount_setattr(int dfd, const char *path, unsigned flags,
struct mount_attr *uattr, size_t usize);
Flags to modify path resolution behavior are specified in the @flags
argument. Currently, AT_EMPTY_PATH, AT_RECURSIVE, AT_SYMLINK_NOFOLLOW,
and AT_NO_AUTOMOUNT are supported. If useful, additional lookup flags to
restrict path resolution as introduced with openat2() might be supported
in the future.
The mount_setattr() syscall can be expected to grow over time and is
designed with extensibility in mind. It follows the extensible syscall
pattern we have used with other syscalls such as openat2(), clone3(),
sched_{set,get}attr(), and others.
The set of mount options is passed in the uapi struct mount_attr which
currently has the following layout:
struct mount_attr {
__u64 attr_set;
__u64 attr_clr;
__u64 propagation;
__u64 userns_fd;
};
The @attr_set and @attr_clr members are used to clear and set mount
options. This way a user can e.g. request that a set of flags is to be
raised such as turning mounts readonly by raising MOUNT_ATTR_RDONLY in
@attr_set while at the same time requesting that another set of flags is
to be lowered such as removing noexec from a mount tree by specifying
MOUNT_ATTR_NOEXEC in @attr_clr.
Note, since the MOUNT_ATTR_<atime> values are an enum starting from 0,
not a bitmap, users wanting to transition to a different atime setting
cannot simply specify the atime setting in @attr_set, but must also
specify MOUNT_ATTR__ATIME in the @attr_clr field. So we ensure that
MOUNT_ATTR__ATIME can't be partially set in @attr_clr and that @attr_set
can't have any atime bits set if MOUNT_ATTR__ATIME isn't set in
@attr_clr.
The @propagation field lets callers specify the propagation type of a
mount tree. Propagation is a single property that has four different
settings and as such is not really a flag argument but an enum.
Specifically, it would be unclear what setting and clearing propagation
settings in combination would amount to. The legacy mount() syscall thus
forbids the combination of multiple propagation settings too. The goal
is to keep the semantics of mount propagation somewhat simple as they
are overly complex as it is.
The @userns_fd field lets user specify a user namespace whose idmapping
becomes the idmapping of the mount. This is implemented and explained in
detail in the next patch.
[1]: commit 2e4b7fcd9260 ("[PATCH] r/o bind mounts: honor mount writer counts at remount")
Link: https://lore.kernel.org/r/20210121131959.646623-35-christian.brauner@ubuntu.com
Cc: David Howells <dhowells@redhat.com>
Cc: Aleksa Sarai <cyphar@cyphar.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Cc: linux-api@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Instead of fetching all registers from struct pt_regs and passing
them to the syscall wrappers, let the system call wrappers only
fetch the values really required.
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
This patch converts s390 to use the generic entry infrastructure from
kernel/entry/*.
There are a few special things on s390:
- PIF_PER_TRAP is moved to TIF_PER_TRAP as the generic code doesn't
know about our PIF flags in exit_to_user_mode_loop().
- The old code had several ways to restart syscalls:
a) PIF_SYSCALL_RESTART, which was only set during execve to force a
restart after upgrading a process (usually qemu-kvm) to pgste page
table extensions.
b) PIF_SYSCALL, which is set by do_signal() to indicate that the
current syscall should be restarted. This is changed so that
do_signal() now also uses PIF_SYSCALL_RESTART. Continuing to use
PIF_SYSCALL doesn't work with the generic code, and changing it
to PIF_SYSCALL_RESTART makes PIF_SYSCALL and PIF_SYSCALL_RESTART
more unique.
- On s390 calling sys_sigreturn or sys_rt_sigreturn is implemented by
executing a svc instruction on the process stack which causes a fault.
While handling that fault the fault code sets PIF_SYSCALL to hand over
processing to the syscall code on exit to usermode.
The patch introduces PIF_SYSCALL_RET_SET, which is set if ptrace sets
a return value for a syscall. The s390x ptrace ABI uses r2 both for the
syscall number and return value, so ptrace cannot set the syscall number +
return value at the same time. The flag makes handling that a bit easier.
do_syscall() will just skip executing the syscall if PIF_SYSCALL_RET_SET
is set.
CONFIG_DEBUG_ASCE was removd in favour of the generic CONFIG_DEBUG_ENTRY.
CR1/7/13 will be checked both on kernel entry and exit to contain the
correct asces.
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Preparations to doing i386 compat elf_prstatus sanely - rather than duplicating
the beginning of compat_elf_prstatus, take these fields into a separate
structure (compat_elf_prstatus_common), so that it could be reused. Due to
the incestous relationship between binfmt_elf.c and compat_binfmt_elf.c we
need the same shape change done to native struct elf_prstatus, gathering the
fields prior to pr_reg into a new structure (struct elf_prstatus_common).
Fortunately, offset of pr_reg is always a multiple of 16 with no padding
right before it, so it's possible to turn all the stuff prior to it into
a single member without disturbing the layout.
[build fix from Geert Uytterhoeven folded in]
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
accesses, inefficient and disfunctional code. The goal is to remove the
export of irq_to_desc() to prevent these things from creeping up again.
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Merge tag 'irq-core-2020-12-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq updates from Thomas Gleixner:
"This is the second attempt after the first one failed miserably and
got zapped to unblock the rest of the interrupt related patches.
A treewide cleanup of interrupt descriptor (ab)use with all sorts of
racy accesses, inefficient and disfunctional code. The goal is to
remove the export of irq_to_desc() to prevent these things from
creeping up again"
* tag 'irq-core-2020-12-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (30 commits)
genirq: Restrict export of irq_to_desc()
xen/events: Implement irq distribution
xen/events: Reduce irq_info:: Spurious_cnt storage size
xen/events: Only force affinity mask for percpu interrupts
xen/events: Use immediate affinity setting
xen/events: Remove disfunct affinity spreading
xen/events: Remove unused bind_evtchn_to_irq_lateeoi()
net/mlx5: Use effective interrupt affinity
net/mlx5: Replace irq_to_desc() abuse
net/mlx4: Use effective interrupt affinity
net/mlx4: Replace irq_to_desc() abuse
PCI: mobiveil: Use irq_data_get_irq_chip_data()
PCI: xilinx-nwl: Use irq_data_get_irq_chip_data()
NTB/msi: Use irq_has_action()
mfd: ab8500-debugfs: Remove the racy fiddling with irq_desc
pinctrl: nomadik: Use irq_has_action()
drm/i915/pmu: Replace open coded kstat_irqs() copy
drm/i915/lpe_audio: Remove pointless irq_to_desc() usage
s390/irq: Use irq_desc_kstat_cpu() in show_msi_interrupt()
parisc/irq: Use irq_desc_kstat_cpu() in show_interrupts()
...
Commit b0a0c2615f6f ("epoll: wire up syscall epoll_pwait2") wired up
the 64 bit syscall instead of the compat variant in a couple of places.
Fixes: b0a0c2615f6f ("epoll: wire up syscall epoll_pwait2")
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge still more updates from Andrew Morton:
"18 patches.
Subsystems affected by this patch series: mm (memcg and cleanups) and
epoll"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
mm/Kconfig: fix spelling mistake "whats" -> "what's"
selftests/filesystems: expand epoll with epoll_pwait2
epoll: wire up syscall epoll_pwait2
epoll: add syscall epoll_pwait2
epoll: convert internal api to timespec64
epoll: eliminate unnecessary lock for zero timeout
epoll: replace gotos with a proper loop
epoll: pull all code between fetch_events and send_event into the loop
epoll: simplify and optimize busy loop logic
epoll: move eavail next to the list_empty_careful check
epoll: pull fatal signal checks into ep_send_events()
epoll: simplify signal handling
epoll: check for events when removing a timed out thread from the wait queue
mm/memcontrol:rewrite mem_cgroup_page_lruvec()
mm, kvm: account kvm_vcpu_mmap to kmemcg
mm/memcg: remove unused definitions
mm/memcg: warning on !memcg after readahead page charged
mm/memcg: bail early from swap accounting if memcg disabled
Split off from prev patch in the series that implements the syscall.
Link: https://lkml.kernel.org/r/20201121144401.3727659-4-willemdebruijn.kernel@gmail.com
Signed-off-by: Willem de Bruijn <willemb@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
that unwinding works properly.
- Fix stack unwinder test case to avoid rare interrupt stack corruption.
- Simplify udelay() and just let it busy loop instead of implementing a
complex logic.
- arch_cpu_idle() cleanup.
- Some other minor improvements.
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Merge tag 's390-5.11-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull more s390 updates from Heiko Carstens:
"This is mainly to decouple udelay() and arch_cpu_idle() and simplify
both of them.
Summary:
- Always initialize kernel stack backchain when entering the kernel,
so that unwinding works properly.
- Fix stack unwinder test case to avoid rare interrupt stack
corruption.
- Simplify udelay() and just let it busy loop instead of implementing
a complex logic.
- arch_cpu_idle() cleanup.
- Some other minor improvements"
* tag 's390-5.11-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/zcrypt: convert comma to semicolon
s390/idle: allow arch_cpu_idle() to be kprobed
s390/idle: remove raw_local_irq_save()/restore() from arch_cpu_idle()
s390/idle: merge enabled_wait() and arch_cpu_idle()
s390/delay: remove udelay_simple()
s390/irq: select HAVE_IRQ_EXIT_ON_IRQ_STACK
s390/delay: simplify udelay
s390/test_unwind: use timer instead of udelay
s390/test_unwind: fix CALL_ON_STACK tests
s390: make calls to TRACE_IRQS_OFF/TRACE_IRQS_ON balanced
s390: always clear kernel stack backchain before calling functions
The major update to this release is that there's a new arch config option called:
CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS. Currently, only x86_64 enables it.
All the ftrace callbacks now take a struct ftrace_regs instead of a struct
pt_regs. If the architecture has HAVE_DYNAMIC_FTRACE_WITH_ARGS enabled, then
the ftrace_regs will have enough information to read the arguments of the
function being traced, as well as access to the stack pointer. This way, if
a user (like live kernel patching) only cares about the arguments, then it
can avoid using the heavier weight "regs" callback, that puts in enough
information in the struct ftrace_regs to simulate a breakpoint exception
(needed for kprobes).
New config option that audits the timestamps of the ftrace ring buffer at
most every event recorded. The "check_buffer()" calls will conflict with
mainline, because I purposely added the check without including the fix that
it caught, which is in mainline. Running a kernel built from the commit of
the added check will trigger it.
Ftrace recursion protection has been cleaned up to move the protection to
the callback itself (this saves on an extra function call for those
callbacks).
Perf now handles its own RCU protection and does not depend on ftrace to do
it for it (saving on that extra function call).
New debug option to add "recursed_functions" file to tracefs that lists all
the places that triggered the recursion protection of the function tracer.
This will show where things need to be fixed as recursion slows down the
function tracer.
The eval enum mapping updates done at boot up are now offloaded to a work
queue, as it caused a noticeable pause on slow embedded boards.
Various clean ups and last minute fixes.
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Merge tag 'trace-v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing updates from Steven Rostedt:
"The major update to this release is that there's a new arch config
option called CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS.
Currently, only x86_64 enables it. All the ftrace callbacks now take a
struct ftrace_regs instead of a struct pt_regs. If the architecture
has HAVE_DYNAMIC_FTRACE_WITH_ARGS enabled, then the ftrace_regs will
have enough information to read the arguments of the function being
traced, as well as access to the stack pointer.
This way, if a user (like live kernel patching) only cares about the
arguments, then it can avoid using the heavier weight "regs" callback,
that puts in enough information in the struct ftrace_regs to simulate
a breakpoint exception (needed for kprobes).
A new config option that audits the timestamps of the ftrace ring
buffer at most every event recorded.
Ftrace recursion protection has been cleaned up to move the protection
to the callback itself (this saves on an extra function call for those
callbacks).
Perf now handles its own RCU protection and does not depend on ftrace
to do it for it (saving on that extra function call).
New debug option to add "recursed_functions" file to tracefs that
lists all the places that triggered the recursion protection of the
function tracer. This will show where things need to be fixed as
recursion slows down the function tracer.
The eval enum mapping updates done at boot up are now offloaded to a
work queue, as it caused a noticeable pause on slow embedded boards.
Various clean ups and last minute fixes"
* tag 'trace-v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (33 commits)
tracing: Offload eval map updates to a work queue
Revert: "ring-buffer: Remove HAVE_64BIT_ALIGNED_ACCESS"
ring-buffer: Add rb_check_bpage in __rb_allocate_pages
ring-buffer: Fix two typos in comments
tracing: Drop unneeded assignment in ring_buffer_resize()
tracing: Disable ftrace selftests when any tracer is running
seq_buf: Avoid type mismatch for seq_buf_init
ring-buffer: Fix a typo in function description
ring-buffer: Remove obsolete rb_event_is_commit()
ring-buffer: Add test to validate the time stamp deltas
ftrace/documentation: Fix RST C code blocks
tracing: Clean up after filter logic rewriting
tracing: Remove the useless value assignment in test_create_synth_event()
livepatch: Use the default ftrace_ops instead of REGS when ARGS is available
ftrace/x86: Allow for arguments to be passed in to ftrace_regs by default
ftrace: Have the callbacks receive a struct ftrace_regs instead of pt_regs
MAINTAINERS: assign ./fs/tracefs to TRACING
tracing: Fix some typos in comments
ftrace: Remove unused varible 'ret'
ring-buffer: Add recording of ring buffer recursion into recursed_functions
...
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Merge tag 'tif-task_work.arch-2020-12-14' of git://git.kernel.dk/linux-block
Pull TIF_NOTIFY_SIGNAL updates from Jens Axboe:
"This sits on top of of the core entry/exit and x86 entry branch from
the tip tree, which contains the generic and x86 parts of this work.
Here we convert the rest of the archs to support TIF_NOTIFY_SIGNAL.
With that done, we can get rid of JOBCTL_TASK_WORK from task_work and
signal.c, and also remove a deadlock work-around in io_uring around
knowing that signal based task_work waking is invoked with the sighand
wait queue head lock.
The motivation for this work is to decouple signal notify based
task_work, of which io_uring is a heavy user of, from sighand. The
sighand lock becomes a huge contention point, particularly for
threaded workloads where it's shared between threads. Even outside of
threaded applications it's slower than it needs to be.
Roman Gershman <romger@amazon.com> reported that his networked
workload dropped from 1.6M QPS at 80% CPU to 1.0M QPS at 100% CPU
after io_uring was changed to use TIF_NOTIFY_SIGNAL. The time was all
spent hammering on the sighand lock, showing 57% of the CPU time there
[1].
There are further cleanups possible on top of this. One example is
TIF_PATCH_PENDING, where a patch already exists to use
TIF_NOTIFY_SIGNAL instead. Hopefully this will also lead to more
consolidation, but the work stands on its own as well"
[1] https://github.com/axboe/liburing/issues/215
* tag 'tif-task_work.arch-2020-12-14' of git://git.kernel.dk/linux-block: (28 commits)
io_uring: remove 'twa_signal_ok' deadlock work-around
kernel: remove checking for TIF_NOTIFY_SIGNAL
signal: kill JOBCTL_TASK_WORK
io_uring: JOBCTL_TASK_WORK is no longer used by task_work
task_work: remove legacy TWA_SIGNAL path
sparc: add support for TIF_NOTIFY_SIGNAL
riscv: add support for TIF_NOTIFY_SIGNAL
nds32: add support for TIF_NOTIFY_SIGNAL
ia64: add support for TIF_NOTIFY_SIGNAL
h8300: add support for TIF_NOTIFY_SIGNAL
c6x: add support for TIF_NOTIFY_SIGNAL
alpha: add support for TIF_NOTIFY_SIGNAL
xtensa: add support for TIF_NOTIFY_SIGNAL
arm: add support for TIF_NOTIFY_SIGNAL
microblaze: add support for TIF_NOTIFY_SIGNAL
hexagon: add support for TIF_NOTIFY_SIGNAL
csky: add support for TIF_NOTIFY_SIGNAL
openrisc: add support for TIF_NOTIFY_SIGNAL
sh: add support for TIF_NOTIFY_SIGNAL
um: add support for TIF_NOTIFY_SIGNAL
...
Remove NOKPROBE_SYMBOL() for arch_cpu_idle(). This might have made
sense when enabled_wait() (aka arch_cpu_idle()) was called from
udelay.
But now there shouldn't be a reason why s390 should be the only
architecture which doesn't allow arch_cpu_idle() to be probed.
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
arch_cpu_idle() gets called with interrupts disabled,
and psw_idle() returns with interrupts disabled.
No reason to use raw_local_irq_save() / restore().
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
The only caller of enabled_wait() besides arch_cpu_idle() was
udelay(). Since that call doesn't exist anymore, merge enabled_wait()
and arch_cpu_idle().
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
udelay_simple() callers can make use of the now simplified udelay()
implementation. No need to keep it.
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
udelay is implemented by using quite subtle details to make it
possible to load an idle psw and waiting for an interrupt even in irq
context or when interrupts are disabled. Also handling (or better: no
handling) of softirqs is taken into account.
All this is done to optimize for something which should in normal
circumstances never happen: calling udelay to busy wait. Therefore get
rid of the whole complexity and just busy loop like other
architectures are doing it also.
It could have been possible to use diag 0x44 instead of cpu_relax() in
the busy loop, however we have seen too many bad things happen with
diag 0x44 that it seems to be better to simply busy loop.
Also note that with this new implementation kernel preemption does
work when within the udelay loop. This did not work before.
To get a feeling what the former code optimizes for: IPL'ing a kernel
with 'defconfig' and afterwards compiling a kernel ends with a total
of zero udelay calls.
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
In case of udelay CIF_IGNORE_IRQ is set. This leads to an unbalanced
call of TRACE_IRQS_OFF and TRACE_IRQS_ON. That is: from lockdep's
point of view TRACE_IRQS_ON is called one time too often.
This doesn't fix any real bug, just makes the calls balanced.
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Clear the kernel stack backchain before potentially calling the
lockdep trace_hardirqs_off/on functions. Without this walking the
kernel backchain, e.g. during a panic, might stop too early.
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Core:
- Consolidation and robustness changes for irq time accounting
- Cleanup and consolidation of irq stats
- Remove the fasteoi IPI flow which has been proved useless
- Provide an interface for converting legacy interrupt mechanism into
irqdomains
Drivers:
The rare event of not having completely new chip driver code, just new
DT bindings and extensions of existing drivers to accomodate new
variants!
- Preliminary support for managed interrupts on platform devices
- Correctly identify allocation of MSIs proxyied by another device
- Generalise the Ocelot support to new SoCs
- Improve GICv4.1 vcpu entry, matching the corresponding KVM optimisation
- Work around spurious interrupts on Qualcomm PDC
- Random fixes and cleanups
Thanks,
tglx
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Merge tag 'irq-core-2020-12-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq updates from Thomas Gleixner:
"Generic interrupt and irqchips subsystem updates. Unusually, there is
not a single completely new irq chip driver, just new DT bindings and
extensions of existing drivers to accomodate new variants!
Core:
- Consolidation and robustness changes for irq time accounting
- Cleanup and consolidation of irq stats
- Remove the fasteoi IPI flow which has been proved useless
- Provide an interface for converting legacy interrupt mechanism into
irqdomains
Drivers:
- Preliminary support for managed interrupts on platform devices
- Correctly identify allocation of MSIs proxyied by another device
- Generalise the Ocelot support to new SoCs
- Improve GICv4.1 vcpu entry, matching the corresponding KVM
optimisation
- Work around spurious interrupts on Qualcomm PDC
- Random fixes and cleanups"
* tag 'irq-core-2020-12-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (54 commits)
irqchip/qcom-pdc: Fix phantom irq when changing between rising/falling
driver core: platform: Add devm_platform_get_irqs_affinity()
ACPI: Drop acpi_dev_irqresource_disabled()
resource: Add irqresource_disabled()
genirq/affinity: Add irq_update_affinity_desc()
irqchip/gic-v3-its: Flag device allocation as proxied if behind a PCI bridge
irqchip/gic-v3-its: Tag ITS device as shared if allocating for a proxy device
platform-msi: Track shared domain allocation
irqchip/ti-sci-intr: Fix freeing of irqs
irqchip/ti-sci-inta: Fix printing of inta id on probe success
drivers/irqchip: Remove EZChip NPS interrupt controller
Revert "genirq: Add fasteoi IPI flow"
irqchip/hip04: Make IPIs use handle_percpu_devid_irq()
irqchip/bcm2836: Make IPIs use handle_percpu_devid_irq()
irqchip/armada-370-xp: Make IPIs use handle_percpu_devid_irq()
irqchip/gic, gic-v3: Make SGIs use handle_percpu_devid_irq()
irqchip/ocelot: Add support for Jaguar2 platforms
irqchip/ocelot: Add support for Serval platforms
irqchip/ocelot: Add support for Luton platforms
irqchip/ocelot: prepare to support more SoC
...
Merge misc updates from Andrew Morton:
- a few random little subsystems
- almost all of the MM patches which are staged ahead of linux-next
material. I'll trickle to post-linux-next work in as the dependents
get merged up.
Subsystems affected by this patch series: kthread, kbuild, ide, ntfs,
ocfs2, arch, and mm (slab-generic, slab, slub, dax, debug, pagecache,
gup, swap, shmem, memcg, pagemap, mremap, hmm, vmalloc, documentation,
kasan, pagealloc, memory-failure, hugetlb, vmscan, z3fold, compaction,
oom-kill, migration, cma, page-poison, userfaultfd, zswap, zsmalloc,
uaccess, zram, and cleanups).
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (200 commits)
mm: cleanup kstrto*() usage
mm: fix fall-through warnings for Clang
mm: slub: convert sysfs sprintf family to sysfs_emit/sysfs_emit_at
mm: shmem: convert shmem_enabled_show to use sysfs_emit_at
mm:backing-dev: use sysfs_emit in macro defining functions
mm: huge_memory: convert remaining use of sprintf to sysfs_emit and neatening
mm: use sysfs_emit for struct kobject * uses
mm: fix kernel-doc markups
zram: break the strict dependency from lzo
zram: add stat to gather incompressible pages since zram set up
zram: support page writeback
mm/process_vm_access: remove redundant initialization of iov_r
mm/zsmalloc.c: rework the list_add code in insert_zspage()
mm/zswap: move to use crypto_acomp API for hardware acceleration
mm/zswap: fix passing zero to 'PTR_ERR' warning
mm/zswap: make struct kernel_param_ops definitions const
userfaultfd/selftests: hint the test runner on required privilege
userfaultfd/selftests: fix retval check for userfaultfd_open()
userfaultfd/selftests: always dump something in modes
userfaultfd: selftests: make __{s,u}64 format specifiers portable
...
Don't allow splitting of vm_special_mapping's. It affects vdso/vvar
areas. Uprobes have only one page in xol_area so they aren't affected.
Those restrictions were enforced by checks in .mremap() callbacks.
Restrict resizing with generic .split() callback.
Link: https://lkml.kernel.org/r/20201013013416.390574-7-dima@arista.com
Signed-off-by: Dmitry Safonov <dima@arista.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Brian Geffon <bgeffon@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- Preliminary support for managed interrupts on platform devices
- Correctly identify allocation of MSIs proxyied by another device
- Remove the fasteoi IPI flow which has been proved useless
- Generalise the Ocelot support to new SoCs
- Improve GICv4.1 vcpu entry, matching the corresponding KVM optimisation
- Work around spurious interrupts on Qualcomm PDC
- Random fixes and cleanups
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Merge tag 'irqchip-5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/core
Pull irqchip updates for 5.11 from Marc Zyngier:
- Preliminary support for managed interrupts on platform devices
- Correctly identify allocation of MSIs proxyied by another device
- Remove the fasteoi IPI flow which has been proved useless
- Generalise the Ocelot support to new SoCs
- Improve GICv4.1 vcpu entry, matching the corresponding KVM optimisation
- Work around spurious interrupts on Qualcomm PDC
- Random fixes and cleanups
Link: https://lore.kernel.org/r/20201212135626.1479884-1-maz@kernel.org
hugepages using CMA:
- Add arch_get_random_long() support.
- Add ap bus userspace notifications.
- Increase default size of vmalloc area to 512GB and otherwise let it increase
dynamically by the size of physical memory. This should fix all occurrences
where the vmalloc area was not large enough.
- Completely get rid of set_fs() (aka select SET_FS) and rework address space
handling while doing that; making address space handling much more simple.
- Reimplement getcpu vdso syscall in C.
- Add support for extended SCLP responses (> 4k). This allows e.g. to handle
also potential large system configurations.
- Simplify KASAN by removing 3-level page table support and only supporting
4-levels from now on.
- Improve debug-ability of the kernel decompressor code, which now prints also
stack traces and symbols in case of problems to the console.
- Remove more power management leftovers.
- Other various fixes and improvements all over the place.
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Merge tag 's390-5.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 updates from Heiko Carstens:
- Add support for the hugetlb_cma command line option to allocate
gigantic hugepages using CMA
- Add arch_get_random_long() support.
- Add ap bus userspace notifications.
- Increase default size of vmalloc area to 512GB and otherwise let it
increase dynamically by the size of physical memory. This should fix
all occurrences where the vmalloc area was not large enough.
- Completely get rid of set_fs() (aka select SET_FS) and rework address
space handling while doing that; making address space handling much
more simple.
- Reimplement getcpu vdso syscall in C.
- Add support for extended SCLP responses (> 4k). This allows e.g. to
handle also potential large system configurations.
- Simplify KASAN by removing 3-level page table support and only
supporting 4-levels from now on.
- Improve debug-ability of the kernel decompressor code, which now
prints also stack traces and symbols in case of problems to the
console.
- Remove more power management leftovers.
- Other various fixes and improvements all over the place.
* tag 's390-5.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (62 commits)
s390/mm: add support to allocate gigantic hugepages using CMA
s390/crypto: add arch_get_random_long() support
s390/smp: perform initial CPU reset also for SMT siblings
s390/mm: use invalid asce for user space when switching to init_mm
s390/idle: fix accounting with machine checks
s390/idle: add missing mt_cycles calculation
s390/boot: add build-id to decompressor
s390/kexec_file: fix diag308 subcode when loading crash kernel
s390/cio: fix use-after-free in ccw_device_destroy_console
s390/cio: remove pm support from ccw bus driver
s390/cio: remove pm support from css-bus driver
s390/cio: remove pm support from IO subchannel drivers
s390/cio: remove pm support from chsc subchannel driver
s390/vmur: remove unused pm related functions
s390/tape: remove unsupported PM functions
s390/cio: remove pm support from eadm-sch drivers
s390: remove pm support from console drivers
s390/dasd: remove unused pm related functions
s390/zfcp: remove pm support from zfcp driver
s390/ap: let bus_register() add the AP bus sysfs attributes
...
Commit cf11e85fc08c ("mm: hugetlb: optionally allocate gigantic hugepages
using cma") added support for allocating gigantic hugepages using CMA,
by specifying the hugetlb_cma= kernel parameter, which will disable any
boot-time allocation of gigantic hugepages.
This patch enables that option also for s390.
Signed-off-by: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Not resetting the SMT siblings might leave them in unpredictable
state. One of the observed problems was that the CPU timer wasn't
reset and therefore large system time values where accounted during
CPU bringup.
Cc: <stable@kernel.org> # 4.0
Fixes: 10ad34bc76dfb ("s390: add SMT support")
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
When a machine check interrupt is triggered during idle, the code
is using the async timer/clock for idle time calculation. It should use
the machine check enter timer/clock which is passed to the macro.
Fixes: 0b0ed657fe00 ("s390: remove critical section cleanup from entry.S")
Cc: <stable@vger.kernel.org> # 5.8
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
During removal of the critical section cleanup the calculation
of mt_cycles during idle was removed. This causes invalid
accounting on systems with SMT enabled.
Fixes: 0b0ed657fe00 ("s390: remove critical section cleanup from entry.S")
Cc: <stable@vger.kernel.org> # 5.8
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
The 3 architectures implementing CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
all have their own version of irq time accounting that dispatch the
cputime to the appropriate index: hardirq, softirq, system, idle,
guest... from an all-in-one function.
Instead of having these ad-hoc versions, move the cputime destination
dispatch decision to the core code and leave only the actual per-index
cputime accounting to the architecture.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20201202115732.27827-4-frederic@kernel.org
s390 has its own version of IRQ entry accounting because it doesn't
account the idle time the same way the other architectures do. Only
the actual idle sleep time is accounted as idle time, the rest of the
idle task execution is accounted as system time.
Make the generic IRQ entry accounting aware of architectures that have
their own way of accounting idle time and convert s390 to use it.
This prepares s390 to get involved in further consolidations of IRQ
time accounting.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20201202115732.27827-3-frederic@kernel.org
account_irq_enter_time() and account_irq_exit_time() are not called
from modules. EXPORT_SYMBOL_GPL() can be safely removed from the IRQ
cputime accounting functions called from there.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20201202115732.27827-2-frederic@kernel.org
With commit 58c644ba512c ("sched/idle: Fix arch_cpu_idle() vs
tracing") common code calls arch_cpu_idle() with a lockdep state that
tells irqs are on.
This doesn't work very well for s390: psw_idle() will enable interrupts
to wait for an interrupt. As soon as an interrupt occurs the interrupt
handler will verify if the old context was psw_idle(). If that is the
case the interrupt enablement bits in the old program status word will
be cleared.
A subsequent test in both the external as well as the io interrupt
handler checks if in the old context interrupts were enabled. Due to
the above patching of the old program status word it is assumed the
old context had interrupts disabled, and therefore a call to
TRACE_IRQS_OFF (aka trace_hardirqs_off_caller) is skipped. Which in
turn makes lockdep incorrectly "think" that interrupts are enabled
within the interrupt handler.
Fix this by unconditionally calling TRACE_IRQS_OFF when entering
interrupt handlers. Also call unconditionally TRACE_IRQS_ON when
leaving interrupts handlers.
This leaves the special psw_idle() case, which now returns with
interrupts disabled, but has an "irqs on" lockdep state. So callers of
psw_idle() must adjust the state on their own, if required. This is
currently only __udelay_disabled().
Fixes: 58c644ba512c ("sched/idle: Fix arch_cpu_idle() vs tracing")
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
clang W=1 warns about missing prototypes:
>> arch/s390/kernel/vdso64/getcpu.c:8:5: warning: no previous prototype for function '__s390_vdso_getcpu' [-Wmissing-prototypes]
int __s390_vdso_getcpu(unsigned *cpu, unsigned *node, struct getcpu_cache *unused)
^
Add a local header file in order to get rid of this warnings.
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
idle path. Similar to the entry path the low level idle functions have to
be non-instrumentable.
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Merge tag 'locking-urgent-2020-11-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking fixes from Thomas Gleixner:
"Two more places which invoke tracing from RCU disabled regions in the
idle path.
Similar to the entry path the low level idle functions have to be
non-instrumentable"
* tag 'locking-urgent-2020-11-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
intel_idle: Fix intel_idle() vs tracing
sched/idle: Fix arch_cpu_idle() vs tracing
- Fix alignment of the new HYP sections
- Fix GICR_TYPER access from userspace
S390:
- do not reset the global diag318 data for per-cpu reset
- do not mark memory as protected too early
- fix for destroy page ultravisor call
x86:
- fix for SEV debugging
- fix incorrect return code
- fix for "noapic" with PIC in userspace and LAPIC in kernel
- fix for 5-level paging
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm fixes from Paolo Bonzini:
"ARM:
- Fix alignment of the new HYP sections
- Fix GICR_TYPER access from userspace
S390:
- do not reset the global diag318 data for per-cpu reset
- do not mark memory as protected too early
- fix for destroy page ultravisor call
x86:
- fix for SEV debugging
- fix incorrect return code
- fix for 'noapic' with PIC in userspace and LAPIC in kernel
- fix for 5-level paging"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
kvm: x86/mmu: Fix get_mmio_spte() on CPUs supporting 5-level PT
KVM: x86: Fix split-irqchip vs interrupt injection window request
KVM: x86: handle !lapic_in_kernel case in kvm_cpu_*_extint
MAINTAINERS: Update email address for Sean Christopherson
MAINTAINERS: add uv.c also to KVM/s390
s390/uv: handle destroy page legacy interface
KVM: arm64: vgic-v3: Drop the reporting of GICR_TYPER.Last for userspace
KVM: SVM: fix error return code in svm_create_vcpu()
KVM: SVM: Fix offset computation bug in __sev_dbg_decrypt().
KVM: arm64: Correctly align nVHE percpu data
KVM: s390: remove diag318 reset code
KVM: s390: pv: Mark mm as protected after the set secure parameters and improve cleanup
We call arch_cpu_idle() with RCU disabled, but then use
local_irq_{en,dis}able(), which invokes tracing, which relies on RCU.
Switch all arch_cpu_idle() implementations to use
raw_local_irq_{en,dis}able() and carefully manage the
lockdep,rcu,tracing state like we do in entry.
(XXX: we really should change arch_cpu_idle() to not return with
interrupts enabled)
Reported-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lkml.kernel.org/r/20201120114925.594122626@infradead.org
Implement the previously removed getcpu vdso syscall by using the
TOD programmable field to pass the cpu number to user space.
Reviewed-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Verify on exit to user space that always
- the primary ASCE (cr1) is set to kernel ASCE
- the secondary ASCE (cr7) is set to user ASCE
If this is not the case: panic since something went terribly wrong.
Reviewed-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Create a region 3 page table which contains only invalid entries, and
use that via "s390_invalid_asce" instead of the kernel ASCE whenever
there is either
- no user address space available, e.g. during early startup
- as an intermediate ASCE when address spaces are switched
This makes sure that user space accesses in such situations are
guaranteed to fail.
Reviewed-by: Sven Schnelle <svens@linux.ibm.com>
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Remove set_fs support from s390. With doing this rework address space
handling and simplify it. As a result address spaces are now setup
like this:
CPU running in | %cr1 ASCE | %cr7 ASCE | %cr13 ASCE
----------------------------|-----------|-----------|-----------
user space | user | user | kernel
kernel, normal execution | kernel | user | kernel
kernel, kvm guest execution | gmap | user | kernel
To achieve this the getcpu vdso syscall is removed in order to avoid
secondary address mode and a separate vdso address space in for user
space. The getcpu vdso syscall will be implemented differently with a
subsequent patch.
The kernel accesses user space always via secondary address space.
This happens in different ways:
- with mvcos in home space mode and directly read/write to secondary
address space
- with mvcs/mvcp in primary space mode and copy from primary space to
secondary space or vice versa
- with e.g. cs in secondary space mode and access secondary space
Switching translation modes happens with sacf before and after
instructions which access user space, like before.
Lazy handling of control register reloading is removed in the hope to
make everything simpler, but at the cost of making kernel entry and
exit a bit slower. That is: on kernel entry the primary asce is always
changed to contain the kernel asce, and on kernel exit the primary
asce is changed again so it contains the user asce.
In kernel mode there is only one exception to the primary asce: when
kvm guests are executed the primary asce contains the gmap asce (which
describes the guest address space). The primary asce is reset to
kernel asce whenever kvm guest execution is interrupted, so that this
doesn't has to be taken into account for any user space accesses.
Reviewed-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
We need to disable interrupts in load_fpu_regs(). Otherwise an
interrupt might come in after the registers are loaded, but before
CIF_FPU is cleared in load_fpu_regs(). When the interrupt returns,
CIF_FPU will be cleared and the registers will never be restored.
The entry.S code usually saves the interrupt state in __SF_EMPTY on the
stack when disabling/restoring interrupts. sie64a however saves the pointer
to the sie control block in __SF_SIE_CONTROL, which references the same
location. This is non-obvious to the reader. To avoid thrashing the sie
control block pointer in load_fpu_regs(), move the __SIE_* offsets eight
bytes after __SF_EMPTY on the stack.
Cc: <stable@vger.kernel.org> # 5.8
Fixes: 0b0ed657fe00 ("s390: remove critical section cleanup from entry.S")
Reported-by: Pierre Morel <pmorel@linux.ibm.com>
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Instead of creating the sysfs attributes for the stp root_dev by hand,
pass them to subsys_system_register() as parameter.
This also ensures that the attributes are available when the KOBJ_ADD
event is raised.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Currently the kernel minimal compiler requirement is gcc 4.9 or
clang 10.0.1.
* gcc -mhotpatch option is supported since 4.8.
* A combination of -pg -mrecord-mcount -mnop-mcount -mfentry flags is
supported since gcc 9 and since clang 10.
Drop support for old -pg function prologues. Which leaves binary
compatible -mhotpatch / -mnop-mcount -mfentry prologues in a form:
brcl 0,0
Which are also do not require initial nop optimization / conversion and
presence of _mcount symbol.
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Currently we have to consider too many different values which
in the end only affect identity mapping size. These are:
1. max_physmem_end - end of physical memory online or standby.
Always <= end of the last online memory block (get_mem_detect_end()).
2. CONFIG_MAX_PHYSMEM_BITS - the maximum size of physical memory the
kernel is able to support.
3. "mem=" kernel command line option which limits physical memory usage.
4. OLDMEM_BASE which is a kdump memory limit when the kernel is executed as
crash kernel.
5. "hsa" size which is a memory limit when the kernel is executed during
zfcp/nvme dump.
Through out kernel startup and run we juggle all those values at once
but that does not bring any amusement, only confusion and complexity.
Unify all those values to a single one we should really care, that is
our identity mapping size.
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
System call and program check handler both use the system call exit
path when returning to previous context. However the program check
handler jumps right to the end of the system call exit path if the
previous context is kernel context.
This lead to the quite odd double disabling of interrupts in the
system call exit path introduced with commit ce9dfafe29be ("s390:
fix system call exit path").
To avoid that have a separate program check handler exit path if the
previous context is kernel context.
Reviewed-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
