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Pull x86 fixes from Ingo Molnar:
"Two fixes:
- A PCID related revert that fixes power management and performance
regressions.
- The module loader robustization and sanity check commit is rather
fresh, but it looked like a good idea to apply because of the
hidden data corruption problem such invalid modules could cause"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/module: Detect and skip invalid relocations
Revert "x86/mm: Stop calling leave_mm() in idle code"
Pull RAS fix from Ingo Molnar:
"Fix an RCU warning that triggers when /dev/mcelog is used"
* 'ras-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mcelog: Get rid of RCU remnants
There have been some cases where external tooling (e.g., kpatch-build)
creates a corrupt relocation which targets the wrong address. This is a
silent failure which can corrupt memory in unexpected places.
On x86, the bytes of data being overwritten by relocations are always
initialized to zero beforehand. Use that knowledge to add sanity checks
to detect such cases before they corrupt memory.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: jeyu@kernel.org
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/37450d6c6225e54db107fba447ce9e56e5f758e9.1509713553.git.jpoimboe@redhat.com
[ Restructured the messages, as it's unclear whether the relocation or the target is corrupted. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull perf fixes from Ingo Molnar:
"Various fixes:
- synchronize kernel and tooling headers
- cgroup support fix
- two tooling fixes"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
tools/headers: Synchronize kernel ABI headers
perf/cgroup: Fix perf cgroup hierarchy support
perf tools: Unwind properly location after REJECT
perf symbols: Fix memory corruption because of zero length symbols
Jeremy reported a suspicious RCU usage warning in mcelog.
/dev/mcelog is called in process context now as part of the notifier
chain and doesn't need any of the fancy RCU and lockless accesses which
it did in atomic context.
Axe it all in favor of a simple mutex synchronization which cures the
problem reported.
Fixes: 5de97c9f6d85 ("x86/mce: Factor out and deprecate the /dev/mcelog driver")
Reported-by: Jeremy Cline <jcline@redhat.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-and-tested-by: Tony Luck <tony.luck@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: linux-edac@vger.kernel.org
Cc: Laura Abbott <labbott@redhat.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20171101164754.xzzmskl4ngrqc5br@pd.tnic
Link: https://bugzilla.redhat.com/show_bug.cgi?id=1498969
This reverts commit 43858b4f25cf0adc5c2ca9cf5ce5fdf2532941e5.
The reason I removed the leave_mm() calls in question is because the
heuristic wasn't needed after that patch. With the original version
of my PCID series, we never flushed a "lazy cpu" (i.e. a CPU running
kernel thread) due a flush on the loaded mm.
Unfortunately, that caused architectural issues, so now I've
reinstated these flushes on non-PCID systems in:
commit b956575bed91 ("x86/mm: Flush more aggressively in lazy TLB mode").
That, in turn, gives us a power management and occasionally
performance regression as compared to old kernels: a process that
goes into a deep idle state on a given CPU and gets its mm flushed
due to activity on a different CPU will wake the idle CPU.
Reinstate the old ugly heuristic: if a CPU goes into ACPI C3 or an
intel_idle state that is likely to cause a TLB flush gets its mm
switched to init_mm before going idle.
FWIW, this heuristic is lousy. Whether we should change CR3 before
idle isn't a good hint except insofar as the performance hit is a bit
lower if the TLB is getting flushed by the idle code anyway. What we
really want to know is whether we anticipate being idle long enough
that the mm is likely to be flushed before we wake up. This is more a
matter of the expected latency than the idle state that gets chosen.
This heuristic also completely fails on systems that don't know
whether the TLB will be flushed (e.g. AMD systems?). OTOH it may be a
bit obsolete anyway -- PCID systems don't presently benefit from this
heuristic at all.
We also shouldn't do this callback from innermost bit of the idle code
due to the RCU nastiness it causes. All the information need is
available before rcu_idle_enter() needs to happen.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 43858b4f25cf "x86/mm: Stop calling leave_mm() in idle code"
Link: http://lkml.kernel.org/r/c513bbd4e653747213e05bc7062de000bf0202a5.1509793738.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull irq fix from Ingo Molnar:
"An irqchip driver init fix"
* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irqchip/irq-mvebu-gicp: Add missing spin_lock init
After the SPDX license tags were added a number of tooling headers got out of
sync with their kernel variants, generating lots of build warnings.
Sync them:
- tools/arch/x86/include/asm/disabled-features.h,
tools/arch/x86/include/asm/required-features.h,
tools/include/linux/hash.h:
Remove the SPDX tag where the kernel version does not have it.
- tools/include/asm-generic/bitops/__fls.h,
tools/include/asm-generic/bitops/arch_hweight.h,
tools/include/asm-generic/bitops/const_hweight.h,
tools/include/asm-generic/bitops/fls.h,
tools/include/asm-generic/bitops/fls64.h,
tools/include/uapi/asm-generic/ioctls.h,
tools/include/uapi/asm-generic/mman-common.h,
tools/include/uapi/sound/asound.h,
tools/include/uapi/linux/kvm.h,
tools/include/uapi/linux/perf_event.h,
tools/include/uapi/linux/sched.h,
tools/include/uapi/linux/vhost.h,
tools/include/uapi/sound/asound.h:
Add the SPDX tag of the respective kernel header.
- tools/include/uapi/linux/bpf_common.h,
tools/include/uapi/linux/fcntl.h,
tools/include/uapi/linux/hw_breakpoint.h,
tools/include/uapi/linux/mman.h,
tools/include/uapi/linux/stat.h,
Change the tag to the kernel header version:
-/* SPDX-License-Identifier: GPL-2.0 */
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
Also sync other header details:
- include/uapi/sound/asound.h:
Fix pointless end of line whitespace noise the header grew in this cycle.
- tools/arch/x86/lib/memcpy_64.S:
Sync the code and add tools/include/asm/export.h with dummy wrappers
to support building the kernel side code in a tooling header environment.
- tools/include/uapi/asm-generic/mman.h,
tools/include/uapi/linux/bpf.h:
Sync other details that don't impact tooling's use of the ABIs.
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
IB device index is nldev's handler and it should be checked always.
Fixes: c3f66f7b0052 ("RDMA/netlink: Implement nldev port doit callback")
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Acked-by: Doug Ledford <dledford@redhat.com>
[ Applying directly, since Doug fried his SSD's and is rebuilding - Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull power management fix from Rafael Wysocki:
"This fixes new breakage introduced by the most recent PM QoS fix in
which, embarrassingly enough, I forgot to update
dev_pm_qos_raw_read_value() to return the right default for devices
with no PM QoS constraints at all which prevents runtime PM from
suspending those devices (fix from Tero Kristo)"
* tag 'pm-urgent-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
PM / QoS: Fix default runtime_pm device resume latency
Pull core fixes from Ingo Molnar:
- workaround for gcc asm handling
- futex race fixes
- objtool build warning fix
- two watchdog fixes: a crash fix (revert) and a bug fix for
/proc/sys/kernel/watchdog_thresh handling.
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
objtool: Prevent GCC from merging annotate_unreachable(), take 2
objtool: Resync objtool's instruction decoder source code copy with the kernel's latest version
watchdog/hardlockup/perf: Use atomics to track in-use cpu counter
watchdog/harclockup/perf: Revert a33d44843d45 ("watchdog/hardlockup/perf: Simplify deferred event destroy")
futex: Fix more put_pi_state() vs. exit_pi_state_list() races
A spin lock is used in the irq-mvebu-gicp driver, but it is never
initialized. This patch adds the missing spin_lock_init() call in the
driver's probe function.
Fixes: a68a63cb4dfc ("irqchip/irq-mvebu-gicp: Add new driver for Marvell GICP")
Signed-off-by: Antoine Tenart <antoine.tenart@free-electrons.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: gregory.clement@free-electrons.com
Acked-by: marc.zyngier@arm.com
Cc: thomas.petazzoni@free-electrons.com
Cc: andrew@lunn.ch
Cc: jason@lakedaemon.net
Cc: nadavh@marvell.com
Cc: miquel.raynal@free-electrons.com
Cc: linux-arm-kernel@lists.infradead.org
Cc: sebastian.hesselbarth@gmail.com
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20171025072326.21030-1-antoine.tenart@free-electrons.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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