linux.git/kernel, branch v5.4-rc4 Linux kernel source tree Merge tag 'kbuild-fixes-v5.4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild 2019-10-20T16:36:57+00:00 Linus Torvalds torvalds@linux-foundation.org 2019-10-20T16:36:57+00:00 e2ab4ef83fe279e6f8e06ffa490144d082b95493 Pull more Kbuild fixes from Masahiro Yamada: - fix a bashism of setlocalversion - do not use the too new --sort option of tar * tag 'kbuild-fixes-v5.4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: kheaders: substituting --sort in archive creation scripts: setlocalversion: fix a bashism kbuild: update comment about KBUILD_ALLDIRS 
Pull more Kbuild fixes from Masahiro Yamada:

 - fix a bashism of setlocalversion

 - do not use the too new --sort option of tar

* tag 'kbuild-fixes-v5.4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kheaders: substituting --sort in archive creation
  scripts: setlocalversion: fix a bashism
  kbuild: update comment about KBUILD_ALLDIRS
Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-10-20T10:25:12+00:00 Linus Torvalds torvalds@linux-foundation.org 2019-10-20T10:25:12+00:00 188768f3c0727d4cb95eaad6c67799449aebcc03 Pull hrtimer fixlet from Thomas Gleixner: "A single commit annotating the lockcless access to timer->base with READ_ONCE() and adding the WRITE_ONCE() counterparts for completeness" * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: hrtimer: Annotate lockless access to timer->base 
Pull hrtimer fixlet from Thomas Gleixner:
 "A single commit annotating the lockcless access to timer->base with
  READ_ONCE() and adding the WRITE_ONCE() counterparts for completeness"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  hrtimer: Annotate lockless access to timer->base
Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-10-20T10:22:25+00:00 Linus Torvalds torvalds@linux-foundation.org 2019-10-20T10:22:25+00:00 589f1222e043ab1f5cbce558cfaed0c0fa76e7bb Pull stop-machine fix from Thomas Gleixner: "A single fix, amending stop machine with WRITE/READ_ONCE() to address the fallout of KCSAN" * 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: stop_machine: Avoid potential race behaviour 
Pull stop-machine fix from Thomas Gleixner:
 "A single fix, amending stop machine with WRITE/READ_ONCE() to address
  the fallout of KCSAN"

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  stop_machine: Avoid potential race behaviour
kernel/events/uprobes.c: only do FOLL_SPLIT_PMD for uprobe register 2019-10-19T10:32:33+00:00 Song Liu songliubraving@fb.com 2019-10-19T03:20:40+00:00 aa5de305c90c995321df452f274fe75b52bd8fcc Attaching uprobe to text section in THP splits the PMD mapped page table into PTE mapped entries. On uprobe detach, we would like to regroup PMD mapped page table entry to regain performance benefit of THP. However, the regroup is broken For perf_event based trace_uprobe. This is because perf_event based trace_uprobe calls uprobe_unregister twice on close: first in TRACE_REG_PERF_CLOSE, then in TRACE_REG_PERF_UNREGISTER. The second call will split the PMD mapped page table entry, which is not the desired behavior. Fix this by only use FOLL_SPLIT_PMD for uprobe register case. Add a WARN() to confirm uprobe unregister never work on huge pages, and abort the operation when this WARN() triggers. Link: http://lkml.kernel.org/r/20191017164223.2762148-6-songliubraving@fb.com Fixes: 5a52c9df62b4 ("uprobe: use FOLL_SPLIT_PMD instead of FOLL_SPLIT") Signed-off-by: Song Liu <songliubraving@fb.com> Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: William Kucharski <william.kucharski@oracle.com> Cc: Yang Shi <yang.shi@linux.alibaba.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> 
Attaching uprobe to text section in THP splits the PMD mapped page table
into PTE mapped entries.  On uprobe detach, we would like to regroup PMD
mapped page table entry to regain performance benefit of THP.

However, the regroup is broken For perf_event based trace_uprobe.  This
is because perf_event based trace_uprobe calls uprobe_unregister twice
on close: first in TRACE_REG_PERF_CLOSE, then in
TRACE_REG_PERF_UNREGISTER.  The second call will split the PMD mapped
page table entry, which is not the desired behavior.

Fix this by only use FOLL_SPLIT_PMD for uprobe register case.

Add a WARN() to confirm uprobe unregister never work on huge pages, and
abort the operation when this WARN() triggers.

Link: http://lkml.kernel.org/r/20191017164223.2762148-6-songliubraving@fb.com
Fixes: 5a52c9df62b4 ("uprobe: use FOLL_SPLIT_PMD instead of FOLL_SPLIT")
Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: William Kucharski <william.kucharski@oracle.com>
Cc: Yang Shi <yang.shi@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge tag 'pm-5.4-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm 2019-10-18T15:34:04+00:00 Linus Torvalds torvalds@linux-foundation.org 2019-10-18T15:34:04+00:00 e59b76ff67e527e58914409f13a9cffa1cbf42e7 Pull power management fixes from Rafael Wysocki: "These include a fix for a recent regression in the ACPI CPU performance scaling code, a PCI device power management fix, a system shutdown fix related to cpufreq, a removal of an ACPI suspend-to-idle blacklist entry and a build warning fix. Specifics: - Fix possible NULL pointer dereference in the ACPI processor scaling initialization code introduced by a recent cpufreq update (Rafael Wysocki). - Fix possible deadlock due to suspending cpufreq too late during system shutdown (Rafael Wysocki). - Make the PCI device system resume code path be more consistent with its PM-runtime counterpart to fix an issue with missing delay on transitions from D3cold to D0 during system resume from suspend-to-idle on some systems (Rafael Wysocki). - Drop Dell XPS13 9360 from the LPS0 Idle _DSM blacklist to make it use suspend-to-idle by default (Mario Limonciello). - Fix build warning in the core system suspend support code (Ben Dooks)" * tag 'pm-5.4-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: ACPI: processor: Avoid NULL pointer dereferences at init time PCI: PM: Fix pci_power_up() PM: sleep: include <linux/pm_runtime.h> for pm_wq cpufreq: Avoid cpufreq_suspend() deadlock on system shutdown ACPI: PM: Drop Dell XPS13 9360 from LPS0 Idle _DSM blacklist 
Pull power management fixes from Rafael Wysocki:
 "These include a fix for a recent regression in the ACPI CPU
performance scaling code, a PCI device power management fix,
a system shutdown fix related to cpufreq, a removal of an ACPI
suspend-to-idle blacklist entry and a build warning fix.

Specifics:

   - Fix possible NULL pointer dereference in the ACPI processor scaling
     initialization code introduced by a recent cpufreq update (Rafael
     Wysocki).

   - Fix possible deadlock due to suspending cpufreq too late during
     system shutdown (Rafael Wysocki).

   - Make the PCI device system resume code path be more consistent with
     its PM-runtime counterpart to fix an issue with missing delay on
     transitions from D3cold to D0 during system resume from
     suspend-to-idle on some systems (Rafael Wysocki).

   - Drop Dell XPS13 9360 from the LPS0 Idle _DSM blacklist to make it
     use suspend-to-idle by default (Mario Limonciello).

   - Fix build warning in the core system suspend support code (Ben
     Dooks)"

* tag 'pm-5.4-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI: processor: Avoid NULL pointer dereferences at init time
  PCI: PM: Fix pci_power_up()
  PM: sleep: include <linux/pm_runtime.h> for pm_wq
  cpufreq: Avoid cpufreq_suspend() deadlock on system shutdown
  ACPI: PM: Drop Dell XPS13 9360 from LPS0 Idle _DSM blacklist
Merge branches 'pm-cpufreq' and 'pm-sleep' 2019-10-18T08:27:55+00:00 Rafael J. Wysocki rafael.j.wysocki@intel.com 2019-10-18T08:27:55+00:00 b23eb5c74e6eb6a0b3fb9cf3eb64481a17ce1cd1 * pm-cpufreq: ACPI: processor: Avoid NULL pointer dereferences at init time cpufreq: Avoid cpufreq_suspend() deadlock on system shutdown * pm-sleep: PM: sleep: include <linux/pm_runtime.h> for pm_wq ACPI: PM: Drop Dell XPS13 9360 from LPS0 Idle _DSM blacklist 
* pm-cpufreq:
  ACPI: processor: Avoid NULL pointer dereferences at init time
  cpufreq: Avoid cpufreq_suspend() deadlock on system shutdown

* pm-sleep:
  PM: sleep: include <linux/pm_runtime.h> for pm_wq
  ACPI: PM: Drop Dell XPS13 9360 from LPS0 Idle _DSM blacklist
stop_machine: Avoid potential race behaviour 2019-10-17T10:47:12+00:00 Mark Rutland mark.rutland@arm.com 2019-10-07T10:45:36+00:00 b1fc5833357524d5d342737913dbe32ff3557bc5 Both multi_cpu_stop() and set_state() access multi_stop_data::state racily using plain accesses. These are subject to compiler transformations which could break the intended behaviour of the code, and this situation is detected by KCSAN on both arm64 and x86 (splats below). Improve matters by using READ_ONCE() and WRITE_ONCE() to ensure that the compiler cannot elide, replay, or tear loads and stores. In multi_cpu_stop() the two loads of multi_stop_data::state are expected to be a consistent value, so snapshot the value into a temporary variable to ensure this. The state transitions are serialized by atomic manipulation of multi_stop_data::num_threads, and other fields in multi_stop_data are not modified while subject to concurrent reads. KCSAN splat on arm64: | BUG: KCSAN: data-race in multi_cpu_stop+0xa8/0x198 and set_state+0x80/0xb0 | | write to 0xffff00001003bd00 of 4 bytes by task 24 on cpu 3: | set_state+0x80/0xb0 | multi_cpu_stop+0x16c/0x198 | cpu_stopper_thread+0x170/0x298 | smpboot_thread_fn+0x40c/0x560 | kthread+0x1a8/0x1b0 | ret_from_fork+0x10/0x18 | | read to 0xffff00001003bd00 of 4 bytes by task 14 on cpu 1: | multi_cpu_stop+0xa8/0x198 | cpu_stopper_thread+0x170/0x298 | smpboot_thread_fn+0x40c/0x560 | kthread+0x1a8/0x1b0 | ret_from_fork+0x10/0x18 | | Reported by Kernel Concurrency Sanitizer on: | CPU: 1 PID: 14 Comm: migration/1 Not tainted 5.3.0-00007-g67ab35a199f4-dirty #3 | Hardware name: linux,dummy-virt (DT) KCSAN splat on x86: | write to 0xffffb0bac0013e18 of 4 bytes by task 19 on cpu 2: | set_state kernel/stop_machine.c:170 [inline] | ack_state kernel/stop_machine.c:177 [inline] | multi_cpu_stop+0x1a4/0x220 kernel/stop_machine.c:227 | cpu_stopper_thread+0x19e/0x280 kernel/stop_machine.c:516 | smpboot_thread_fn+0x1a8/0x300 kernel/smpboot.c:165 | kthread+0x1b5/0x200 kernel/kthread.c:255 | ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:352 | | read to 0xffffb0bac0013e18 of 4 bytes by task 44 on cpu 7: | multi_cpu_stop+0xb4/0x220 kernel/stop_machine.c:213 | cpu_stopper_thread+0x19e/0x280 kernel/stop_machine.c:516 | smpboot_thread_fn+0x1a8/0x300 kernel/smpboot.c:165 | kthread+0x1b5/0x200 kernel/kthread.c:255 | ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:352 | | Reported by Kernel Concurrency Sanitizer on: | CPU: 7 PID: 44 Comm: migration/7 Not tainted 5.3.0+ #1 | Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Marco Elver <elver@google.com> Link: https://lkml.kernel.org/r/20191007104536.27276-1-mark.rutland@arm.com 
Both multi_cpu_stop() and set_state() access multi_stop_data::state
racily using plain accesses. These are subject to compiler
transformations which could break the intended behaviour of the code,
and this situation is detected by KCSAN on both arm64 and x86 (splats
below).

Improve matters by using READ_ONCE() and WRITE_ONCE() to ensure that the
compiler cannot elide, replay, or tear loads and stores.

In multi_cpu_stop() the two loads of multi_stop_data::state are expected to
be a consistent value, so snapshot the value into a temporary variable to
ensure this.

The state transitions are serialized by atomic manipulation of
multi_stop_data::num_threads, and other fields in multi_stop_data are not
modified while subject to concurrent reads.

KCSAN splat on arm64:

| BUG: KCSAN: data-race in multi_cpu_stop+0xa8/0x198 and set_state+0x80/0xb0
|
| write to 0xffff00001003bd00 of 4 bytes by task 24 on cpu 3:
|  set_state+0x80/0xb0
|  multi_cpu_stop+0x16c/0x198
|  cpu_stopper_thread+0x170/0x298
|  smpboot_thread_fn+0x40c/0x560
|  kthread+0x1a8/0x1b0
|  ret_from_fork+0x10/0x18
|
| read to 0xffff00001003bd00 of 4 bytes by task 14 on cpu 1:
|  multi_cpu_stop+0xa8/0x198
|  cpu_stopper_thread+0x170/0x298
|  smpboot_thread_fn+0x40c/0x560
|  kthread+0x1a8/0x1b0
|  ret_from_fork+0x10/0x18
|
| Reported by Kernel Concurrency Sanitizer on:
| CPU: 1 PID: 14 Comm: migration/1 Not tainted 5.3.0-00007-g67ab35a199f4-dirty #3
| Hardware name: linux,dummy-virt (DT)

KCSAN splat on x86:

| write to 0xffffb0bac0013e18 of 4 bytes by task 19 on cpu 2:
|  set_state kernel/stop_machine.c:170 [inline]
|  ack_state kernel/stop_machine.c:177 [inline]
|  multi_cpu_stop+0x1a4/0x220 kernel/stop_machine.c:227
|  cpu_stopper_thread+0x19e/0x280 kernel/stop_machine.c:516
|  smpboot_thread_fn+0x1a8/0x300 kernel/smpboot.c:165
|  kthread+0x1b5/0x200 kernel/kthread.c:255
|  ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:352
|
| read to 0xffffb0bac0013e18 of 4 bytes by task 44 on cpu 7:
|  multi_cpu_stop+0xb4/0x220 kernel/stop_machine.c:213
|  cpu_stopper_thread+0x19e/0x280 kernel/stop_machine.c:516
|  smpboot_thread_fn+0x1a8/0x300 kernel/smpboot.c:165
|  kthread+0x1b5/0x200 kernel/kthread.c:255
|  ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:352
|
| Reported by Kernel Concurrency Sanitizer on:
| CPU: 7 PID: 44 Comm: migration/7 Not tainted 5.3.0+ #1
| Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Marco Elver <elver@google.com>
Link: https://lkml.kernel.org/r/20191007104536.27276-1-mark.rutland@arm.com
kheaders: substituting --sort in archive creation 2019-10-17T00:08:19+00:00 Dmitry Goldin dgoldin+lkml@protonmail.ch 2019-10-09T13:42:14+00:00 700dea5a0bea9f64eba89fae7cb2540326fdfdc1 The option --sort=ORDER was only introduced in tar 1.28 (2014), which is rather new and might not be available in some setups. This patch tries to replicate the previous behaviour as closely as possible to fix the kheaders build for older environments. It does not produce identical archives compared to the previous version due to minor sorting differences but produces reproducible results itself in my tests. Reported-by: Andreas Schwab <schwab@suse.de> Signed-off-by: Dmitry Goldin <dgoldin+lkml@protonmail.ch> Tested-by: Andreas Schwab <schwab@suse.de> Tested-by: Quentin Perret <qperret@google.com> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> 
The option --sort=ORDER was only introduced in tar 1.28 (2014), which
is rather new and might not be available in some setups.

This patch tries to replicate the previous behaviour as closely as
possible to fix the kheaders build for older environments. It does
not produce identical archives compared to the previous version due
to minor sorting differences but produces reproducible results itself
in my tests.

Reported-by: Andreas Schwab <schwab@suse.de>
Signed-off-by: Dmitry Goldin <dgoldin+lkml@protonmail.ch>
Tested-by: Andreas Schwab <schwab@suse.de>
Tested-by: Quentin Perret <qperret@google.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
kthread: make __kthread_queue_delayed_work static 2019-10-16T16:20:58+00:00 Ben Dooks ben.dooks@codethink.co.uk 2019-10-16T11:24:58+00:00 bc88f85c6c09306bd21917e1ae28205e9cd775a7 The __kthread_queue_delayed_work is not exported so make it static, to avoid the following sparse warning: kernel/kthread.c:869:6: warning: symbol '__kthread_queue_delayed_work' was not declared. Should it be static? Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> 
The __kthread_queue_delayed_work is not exported so
make it static, to avoid the following sparse warning:

  kernel/kthread.c:869:6: warning: symbol '__kthread_queue_delayed_work' was not declared. Should it be static?

Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge branch 'parisc-5.4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux 2019-10-15T16:37:01+00:00 Linus Torvalds torvalds@linux-foundation.org 2019-10-15T16:37:01+00:00 02755af0f322fd1d2d7995c1e9fd6f9668511560 Pull parisc fixes from Helge Deller: - Fix a parisc-specific fallout of Christoph's dma_set_mask_and_coherent() patches (Sven) - Fix a vmap memory leak in ioremap()/ioremap() (Helge) - Some minor cleanups and documentation updates (Nick, Helge) * 'parisc-5.4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux: parisc: Remove 32-bit DMA enforcement from sba_iommu parisc: Fix vmap memory leak in ioremap()/iounmap() parisc: prefer __section from compiler_attributes.h parisc: sysctl.c: Use CONFIG_PARISC instead of __hppa_ define MAINTAINERS: Add hp_sdc drivers to parisc arch 
Pull parisc fixes from Helge Deller:

 - Fix a parisc-specific fallout of Christoph's
   dma_set_mask_and_coherent() patches (Sven)

 - Fix a vmap memory leak in ioremap()/ioremap() (Helge)

 - Some minor cleanups and documentation updates (Nick, Helge)

* 'parisc-5.4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: Remove 32-bit DMA enforcement from sba_iommu
  parisc: Fix vmap memory leak in ioremap()/iounmap()
  parisc: prefer __section from compiler_attributes.h
  parisc: sysctl.c: Use CONFIG_PARISC instead of __hppa_ define
  MAINTAINERS: Add hp_sdc drivers to parisc arch