Commit Graph

34678 Commits

Author SHA1 Message Date
Linus Torvalds 4312e0e8d3 A few fixes for timers/timekeeping:
- Prevent undefined behaviour in the timespec64_to_ns() conversion which
     is used for converting user supplied time input to nanoseconds. It
     lacked overflow protection.
 
   - Mark sched_clock_read_begin/retry() to prevent recursion in the tracer
 
   - Remove unused debug functions in the hrtimer and timerlist code
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Merge tag 'timers-urgent-2020-11-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timer fixes from Thomas Gleixner:
 "A few fixes for timers/timekeeping:

   - Prevent undefined behaviour in the timespec64_to_ns() conversion
     which is used for converting user supplied time input to
     nanoseconds. It lacked overflow protection.

   - Mark sched_clock_read_begin/retry() to prevent recursion in the
     tracer

   - Remove unused debug functions in the hrtimer and timerlist code"

* tag 'timers-urgent-2020-11-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  time: Prevent undefined behaviour in timespec64_to_ns()
  timers: Remove unused inline funtion debug_timer_free()
  hrtimer: Remove unused inline function debug_hrtimer_free()
  time/sched_clock: Mark sched_clock_read_begin/retry() as notrace
2020-11-01 11:13:45 -08:00
Linus Torvalds 82423b46fc A single fix for stop machine. Mark functions no trace to prevent a crash
caused by recursion when enabling or disabling a tracer on RISC-V (probably
 all architectures which patch through stop machine).
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Merge tag 'smp-urgent-2020-11-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull smp fix from Thomas Gleixner:
 "A single fix for stop machine.

  Mark functions no trace to prevent a crash caused by recursion when
  enabling or disabling a tracer on RISC-V (probably all architectures
  which patch through stop machine)"

* tag 'smp-urgent-2020-11-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  stop_machine, rcu: Mark functions as notrace
2020-11-01 11:11:38 -08:00
Linus Torvalds 8d99084efc A couple of locking fixes:
- Fix incorrect failure injection handling on the fuxtex code
 
  - Prevent a preemption warning in lockdep when tracking local_irq_enable()
    and interrupts are already enabled
 
  - Remove more raw_cpu_read() usage from lockdep which causes state
    corruption on !X86 architectures.
 
  - Make the nr_unused_locks accounting in lockdep correct again.
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Merge tag 'locking-urgent-2020-11-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull locking fixes from Thomas Gleixner:
 "A couple of locking fixes:

   - Fix incorrect failure injection handling in the fuxtex code

   - Prevent a preemption warning in lockdep when tracking
     local_irq_enable() and interrupts are already enabled

   - Remove more raw_cpu_read() usage from lockdep which causes state
     corruption on !X86 architectures.

   - Make the nr_unused_locks accounting in lockdep correct again"

* tag 'locking-urgent-2020-11-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  lockdep: Fix nr_unused_locks accounting
  locking/lockdep: Remove more raw_cpu_read() usage
  futex: Fix incorrect should_fail_futex() handling
  lockdep: Fix preemption WARN for spurious IRQ-enable
2020-11-01 11:08:17 -08:00
Linus Torvalds 53760f9b74 flexible-array member conversion patches for 5.10-rc2
Hi Linus,
 
 Please, pull the following patches that replace zero-length arrays with
 flexible-array members.
 
 Thanks
 --
 Gustavo
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Merge tag 'flexible-array-conversions-5.10-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux

Pull more flexible-array member conversions from Gustavo A. R. Silva:
 "Replace zero-length arrays with flexible-array members"

* tag 'flexible-array-conversions-5.10-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux:
  printk: ringbuffer: Replace zero-length array with flexible-array member
  net/smc: Replace zero-length array with flexible-array member
  net/mlx5: Replace zero-length array with flexible-array member
  mei: hw: Replace zero-length array with flexible-array member
  gve: Replace zero-length array with flexible-array member
  Bluetooth: btintel: Replace zero-length array with flexible-array member
  scsi: target: tcmu: Replace zero-length array with flexible-array member
  ima: Replace zero-length array with flexible-array member
  enetc: Replace zero-length array with flexible-array member
  fs: Replace zero-length array with flexible-array member
  Bluetooth: Replace zero-length array with flexible-array member
  params: Replace zero-length array with flexible-array member
  tracepoint: Replace zero-length array with flexible-array member
  platform/chrome: cros_ec_proto: Replace zero-length array with flexible-array member
  platform/chrome: cros_ec_commands: Replace zero-length array with flexible-array member
  mailbox: zynqmp-ipi-message: Replace zero-length array with flexible-array member
  dmaengine: ti-cppi5: Replace zero-length array with flexible-array member
2020-10-31 14:31:28 -07:00
Gustavo A. R. Silva a38283da05 printk: ringbuffer: Replace zero-length array with flexible-array member
There is a regular need in the kernel to provide a way to declare having a
dynamically sized set of trailing elements in a structure. Kernel code should
always use “flexible array members”[1] for these cases. The older style of
one-element or zero-length arrays should no longer be used[2].

[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://www.kernel.org/doc/html/v5.9/process/deprecated.html#zero-length-and-one-element-arrays

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-10-30 16:57:42 -05:00
Linus Torvalds 8843f40550 Power management fixes for 5.10-rc2
- Modify Kconfig to prevent configuring either the "conservative"
    or the "ondemand" governor as the default cpufreq governor if
    intel_pstate is selected, in which case "schedutil" is the
    default choice for the default governor setting (Rafael Wysocki).
 
  - Modify the cpufreq core, intel_pstate and the schedutil governor
    to avoid missing updates of the HWP max limit when intel_pstate
    operates in the passive mode with HWP enabled (Rafael Wysocki).
 
  - Fix max_cstate module parameter handling in intel_idle for
    processor models with C-state tables coming from ACPI (Chen Yu).
 
  - Clean up assorted pieces of power management code (Jackie Zamow,
    Tom Rix, Zhang Qilong).
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Merge tag 'pm-5.10-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management fixes from Rafael Wysocki:
 "These fix a few issues related to running intel_pstate in the passive
  mode with HWP enabled, correct the handling of the max_cstate module
  parameter in intel_idle and make a few janitorial changes.

  Specifics:

   - Modify Kconfig to prevent configuring either the "conservative" or
     the "ondemand" governor as the default cpufreq governor if
     intel_pstate is selected, in which case "schedutil" is the default
     choice for the default governor setting (Rafael Wysocki).

   - Modify the cpufreq core, intel_pstate and the schedutil governor to
     avoid missing updates of the HWP max limit when intel_pstate
     operates in the passive mode with HWP enabled (Rafael Wysocki).

   - Fix max_cstate module parameter handling in intel_idle for
     processor models with C-state tables coming from ACPI (Chen Yu).

   - Clean up assorted pieces of power management code (Jackie Zamow,
     Tom Rix, Zhang Qilong)"

* tag 'pm-5.10-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  cpufreq: schedutil: Always call driver if CPUFREQ_NEED_UPDATE_LIMITS is set
  cpufreq: Introduce cpufreq_driver_test_flags()
  cpufreq: speedstep: remove unneeded semicolon
  PM: sleep: fix typo in kernel/power/process.c
  intel_idle: Fix max_cstate for processor models without C-state tables
  cpufreq: intel_pstate: Avoid missing HWP max updates in passive mode
  cpufreq: Introduce CPUFREQ_NEED_UPDATE_LIMITS driver flag
  cpufreq: Avoid configuring old governors as default with intel_pstate
  cpufreq: e_powersaver: remove unreachable break
2020-10-30 12:45:04 -07:00
Peter Zijlstra 1a39340865 lockdep: Fix nr_unused_locks accounting
Chris reported that commit 24d5a3bffef1 ("lockdep: Fix
usage_traceoverflow") breaks the nr_unused_locks validation code
triggered by /proc/lockdep_stats.

By fully splitting LOCK_USED and LOCK_USED_READ it becomes a bad
indicator for accounting nr_unused_locks; simplyfy by using any first
bit.

Fixes: 24d5a3bffef1 ("lockdep: Fix usage_traceoverflow")
Reported-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://lkml.kernel.org/r/20201027124834.GL2628@hirez.programming.kicks-ass.net
2020-10-30 17:07:18 +01:00
Peter Zijlstra d48e385003 locking/lockdep: Remove more raw_cpu_read() usage
I initially thought raw_cpu_read() was OK, since if it is !0 we have
IRQs disabled and can't get migrated, so if we get migrated both CPUs
must have 0 and it doesn't matter which 0 we read.

And while that is true; it isn't the whole store, on pretty much all
architectures (except x86) this can result in computing the address for
one CPU, getting migrated, the old CPU continuing execution with another
task (possibly setting recursion) and then the new CPU reading the value
of the old CPU, which is no longer 0.

Similer to:

  baffd723e4 ("lockdep: Revert "lockdep: Use raw_cpu_*() for per-cpu variables"")

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20201026152256.GB2651@hirez.programming.kicks-ass.net
2020-10-30 17:07:18 +01:00
Rafael J. Wysocki dea47cf45a Merge branches 'pm-cpuidle' and 'pm-sleep'
* pm-cpuidle:
  intel_idle: Fix max_cstate for processor models without C-state tables

* pm-sleep:
  PM: sleep: fix typo in kernel/power/process.c
2020-10-30 16:30:14 +01:00
Gustavo A. R. Silva fa29c9c11d params: Replace zero-length array with flexible-array member
There is a regular need in the kernel to provide a way to declare having a
dynamically sized set of trailing elements in a structure. Kernel code should
always use “flexible array members”[1] for these cases. The older style of
one-element or zero-length arrays should no longer be used[2].

[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://www.kernel.org/doc/html/v5.9-rc1/process/deprecated.html#zero-length-and-one-element-arrays

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-10-29 17:22:59 -05:00
Gustavo A. R. Silva 9d0a49c702 tracepoint: Replace zero-length array with flexible-array member
There is a regular need in the kernel to provide a way to declare having a
dynamically sized set of trailing elements in a structure. Kernel code should
always use “flexible array members”[1] for these cases. The older style of
one-element or zero-length arrays should no longer be used[2].

[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://www.kernel.org/doc/html/v5.9-rc1/process/deprecated.html#zero-length-and-one-element-arrays

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-10-29 17:22:59 -05:00
Rafael J. Wysocki d1e7c2996e cpufreq: schedutil: Always call driver if CPUFREQ_NEED_UPDATE_LIMITS is set
Because sugov_update_next_freq() may skip a frequency update even if
the need_freq_update flag has been set for the policy at hand, policy
limits updates may not take effect as expected.

For example, if the intel_pstate driver operates in the passive mode
with HWP enabled, it needs to update the HWP min and max limits when
the policy min and max limits change, respectively, but that may not
happen if the target frequency does not change along with the limit
at hand.  In particular, if the policy min is changed first, causing
the target frequency to be adjusted to it, and the policy max limit
is changed later to the same value, the HWP max limit will not be
updated to follow it as expected, because the target frequency is
still equal to the policy min limit and it will not change until
that limit is updated.

To address this issue, modify get_next_freq() to let the driver
callback run if the CPUFREQ_NEED_UPDATE_LIMITS cpufreq driver flag
is set regardless of whether or not the new frequency to set is
equal to the previous one.

Fixes: f6ebbcf08f ("cpufreq: intel_pstate: Implement passive mode with HWP enabled")
Reported-by: Zhang Rui <rui.zhang@intel.com>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Cc: 5.9+ <stable@vger.kernel.org> # 5.9+: 1c534352f4 cpufreq: Introduce CPUFREQ_NEED_UPDATE_LIMITS ...
Cc: 5.9+ <stable@vger.kernel.org> # 5.9+: a62f68f5ca cpufreq: Introduce cpufreq_driver_test_flags()
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-10-29 14:12:18 +01:00
Linus Torvalds 23859ae444 Fix synthetic event "strcat" overrun
New synthetic event code used strcat() and miscalculated the ending, causing
 the concatenation to write beyond the allocated memory.
 
 Instead of using strncat(), the code is switched over to seq_buf which has
 all the mechanisms in place to protect against writing more than what is
 allocated, and cleans up the code a bit.
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Merge tag 'trace-v5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fix from Steven Rostedt:
 "Fix synthetic event "strcat" overrun

  New synthetic event code used strcat() and miscalculated the ending,
  causing the concatenation to write beyond the allocated memory.

  Instead of using strncat(), the code is switched over to seq_buf which
  has all the mechanisms in place to protect against writing more than
  what is allocated, and cleans up the code a bit"

* tag 'trace-v5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing, synthetic events: Replace buggy strcat() with seq_buf operations
2020-10-28 12:05:14 -07:00
Mateusz Nosek 921c7ebd13 futex: Fix incorrect should_fail_futex() handling
If should_futex_fail() returns true in futex_wake_pi(), then the 'ret'
variable is set to -EFAULT and then immediately overwritten. So the failure
injection is non-functional.

Fix it by actually leaving the function and returning -EFAULT.

The Fixes tag is kinda blury because the initial commit which introduced
failure injection was already sloppy, but the below mentioned commit broke
it completely.

[ tglx: Massaged changelog ]

Fixes: 6b4f4bc9cb ("locking/futex: Allow low-level atomic operations to return -EAGAIN")
Signed-off-by: Mateusz Nosek <mateusznosek0@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20200927000858.24219-1-mateusznosek0@gmail.com
2020-10-28 15:48:51 +01:00
Jackie Zamow 4d4ce8053b PM: sleep: fix typo in kernel/power/process.c
Fix a typo in a comment in freeze_processes().

Signed-off-by: Jackie Zamow <jackie.zamow@gmail.com>
[ rjw: Subject and changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-10-27 19:11:44 +01:00
Steven Rostedt (VMware) 761a8c58db tracing, synthetic events: Replace buggy strcat() with seq_buf operations
There was a memory corruption bug happening while running the synthetic
event selftests:

 kmemleak: Cannot insert 0xffff8c196fa2afe5 into the object search tree (overlaps existing)
 CPU: 5 PID: 6866 Comm: ftracetest Tainted: G        W         5.9.0-rc5-test+ #577
 Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v03.03 07/14/2016
 Call Trace:
  dump_stack+0x8d/0xc0
  create_object.cold+0x3b/0x60
  slab_post_alloc_hook+0x57/0x510
  ? tracing_map_init+0x178/0x340
  __kmalloc+0x1b1/0x390
  tracing_map_init+0x178/0x340
  event_hist_trigger_func+0x523/0xa40
  trigger_process_regex+0xc5/0x110
  event_trigger_write+0x71/0xd0
  vfs_write+0xca/0x210
  ksys_write+0x70/0xf0
  do_syscall_64+0x33/0x40
  entry_SYSCALL_64_after_hwframe+0x44/0xa9
 RIP: 0033:0x7fef0a63a487
 Code: 64 89 02 48 c7 c0 ff ff ff ff eb bb 0f 1f 80 00 00 00 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 48 89 54 24 18 48 89 74 24
 RSP: 002b:00007fff76f18398 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
 RAX: ffffffffffffffda RBX: 0000000000000039 RCX: 00007fef0a63a487
 RDX: 0000000000000039 RSI: 000055eb3b26d690 RDI: 0000000000000001
 RBP: 000055eb3b26d690 R08: 000000000000000a R09: 0000000000000038
 R10: 000055eb3b2cdb80 R11: 0000000000000246 R12: 0000000000000039
 R13: 00007fef0a70b500 R14: 0000000000000039 R15: 00007fef0a70b700
 kmemleak: Kernel memory leak detector disabled
 kmemleak: Object 0xffff8c196fa2afe0 (size 8):
 kmemleak:   comm "ftracetest", pid 6866, jiffies 4295082531
 kmemleak:   min_count = 1
 kmemleak:   count = 0
 kmemleak:   flags = 0x1
 kmemleak:   checksum = 0
 kmemleak:   backtrace:
      __kmalloc+0x1b1/0x390
      tracing_map_init+0x1be/0x340
      event_hist_trigger_func+0x523/0xa40
      trigger_process_regex+0xc5/0x110
      event_trigger_write+0x71/0xd0
      vfs_write+0xca/0x210
      ksys_write+0x70/0xf0
      do_syscall_64+0x33/0x40
      entry_SYSCALL_64_after_hwframe+0x44/0xa9

The cause came down to a use of strcat() that was adding an string that was
shorten, but the strcat() did not take that into account.

strcat() is extremely dangerous as it does not care how big the buffer is.
Replace it with seq_buf operations that prevent the buffer from being
overwritten if what is being written is bigger than the buffer.

Fixes: 10819e2579 ("tracing: Handle synthetic event array field type checking correctly")
Reviewed-by: Tom Zanussi <zanussi@kernel.org>
Tested-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-10-27 09:25:36 -04:00
Zong Li 4230e2deaa stop_machine, rcu: Mark functions as notrace
Some architectures assume that the stopped CPUs don't make function calls
to traceable functions when they are in the stopped state. See also commit
cb9d7fd51d ("watchdog: Mark watchdog touch functions as notrace").

Violating this assumption causes kernel crashes when switching tracer on
RISC-V.

Mark rcu_momentary_dyntick_idle() and stop_machine_yield() notrace to
prevent this.

Fixes: 4ecf0a43e7 ("processor: get rid of cpu_relax_yield")
Fixes: 366237e7b0 ("stop_machine: Provide RCU quiescent state in multi_cpu_stop()")
Signed-off-by: Zong Li <zong.li@sifive.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Atish Patra <atish.patra@wdc.com>
Tested-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20201021073839.43935-1-zong.li@sifive.com
2020-10-26 12:12:27 +01:00
Zeng Tao cb47755725 time: Prevent undefined behaviour in timespec64_to_ns()
UBSAN reports:

Undefined behaviour in ./include/linux/time64.h:127:27
signed integer overflow:
17179869187 * 1000000000 cannot be represented in type 'long long int'
Call Trace:
 timespec64_to_ns include/linux/time64.h:127 [inline]
 set_cpu_itimer+0x65c/0x880 kernel/time/itimer.c:180
 do_setitimer+0x8e/0x740 kernel/time/itimer.c:245
 __x64_sys_setitimer+0x14c/0x2c0 kernel/time/itimer.c:336
 do_syscall_64+0xa1/0x540 arch/x86/entry/common.c:295

Commit bd40a17576 ("y2038: itimer: change implementation to timespec64")
replaced the original conversion which handled time clamping correctly with
timespec64_to_ns() which has no overflow protection.

Fix it in timespec64_to_ns() as this is not necessarily limited to the
usage in itimers.

[ tglx: Added comment and adjusted the fixes tag ]

Fixes: 361a3bf005 ("time64: Add time64.h header and define struct timespec64")
Signed-off-by: Zeng Tao <prime.zeng@hisilicon.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/1598952616-6416-1-git-send-email-prime.zeng@hisilicon.com
2020-10-26 11:48:11 +01:00
YueHaibing 9010e3876e timers: Remove unused inline funtion debug_timer_free()
There is no caller in tree, remove it.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20200909134749.32300-1-yuehaibing@huawei.com
2020-10-26 11:39:21 +01:00
YueHaibing 5254cb87c0 hrtimer: Remove unused inline function debug_hrtimer_free()
There is no caller in tree, remove it.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20200909134850.21940-1-yuehaibing@huawei.com
2020-10-26 11:39:21 +01:00
Quanyang Wang 4cd2bb1298 time/sched_clock: Mark sched_clock_read_begin/retry() as notrace
Since sched_clock_read_begin() and sched_clock_read_retry() are called
by notrace function sched_clock(), they shouldn't be traceable either,
or else ftrace_graph_caller will run into a dead loop on the path
as below (arm for instance):

  ftrace_graph_caller()
    prepare_ftrace_return()
      function_graph_enter()
        ftrace_push_return_trace()
          trace_clock_local()
            sched_clock()
              sched_clock_read_begin/retry()

Fixes: 1b86abc1c6 ("sched_clock: Expose struct clock_read_data")
Signed-off-by: Quanyang Wang <quanyang.wang@windriver.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200929082027.16787-1-quanyang.wang@windriver.com
2020-10-26 11:34:31 +01:00
Joe Perches 33def8498f treewide: Convert macro and uses of __section(foo) to __section("foo")
Use a more generic form for __section that requires quotes to avoid
complications with clang and gcc differences.

Remove the quote operator # from compiler_attributes.h __section macro.

Convert all unquoted __section(foo) uses to quoted __section("foo").
Also convert __attribute__((section("foo"))) uses to __section("foo")
even if the __attribute__ has multiple list entry forms.

Conversion done using the script at:

    https://lore.kernel.org/lkml/75393e5ddc272dc7403de74d645e6c6e0f4e70eb.camel@perches.com/2-convert_section.pl

Signed-off-by: Joe Perches <joe@perches.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@gooogle.com>
Reviewed-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-25 14:51:49 -07:00
Rasmus Villemoes 986b9eacb2 kernel/sys.c: fix prototype of prctl_get_tid_address()
tid_addr is not a "pointer to (pointer to int in userspace)"; it is in
fact a "pointer to (pointer to int in userspace) in userspace".  So
sparse rightfully complains about passing a kernel pointer to
put_user().

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-25 11:44:16 -07:00
Linus Torvalds 672f887126 A time namespace fix and a matching selftest. The futex absolute timeouts
which are based on CLOCK_MONOTONIC require time namespace corrected. This
 was missed in the original time namesapce support.
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Merge tag 'timers-urgent-2020-10-25' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timer fixes from Thomas Gleixner:
 "A time namespace fix and a matching selftest. The futex absolute
  timeouts which are based on CLOCK_MONOTONIC require time namespace
  corrected. This was missed in the original time namesapce support"

* tag 'timers-urgent-2020-10-25' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  selftests/timens: Add a test for futex()
  futex: Adjust absolute futex timeouts with per time namespace offset
2020-10-25 11:28:49 -07:00
Linus Torvalds 87702a337f Two scheduler fixes:
- A trivial build fix for sched_feat() to compile correctly with
     CONFIG_JUMP_LABEL=n
 
   - Replace a zero lenght array with a flexible array.
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Merge tag 'sched-urgent-2020-10-25' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull scheduler fixes from Thomas Gleixner:
 "Two scheduler fixes:

   - A trivial build fix for sched_feat() to compile correctly with
     CONFIG_JUMP_LABEL=n

   - Replace a zero lenght array with a flexible array"

* tag 'sched-urgent-2020-10-25' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/features: Fix !CONFIG_JUMP_LABEL case
  sched: Replace zero-length array with flexible-array
2020-10-25 11:25:16 -07:00
Linus Torvalds 81ecf91eab SafeSetID changes for v5.10
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Merge tag 'safesetid-5.10' of git://github.com/micah-morton/linux

Pull SafeSetID updates from Micah Morton:
 "The changes are mostly contained to within the SafeSetID LSM, with the
  exception of a few 1-line changes to change some ns_capable() calls to
  ns_capable_setid() -- causing a flag (CAP_OPT_INSETID) to be set that
  is examined by SafeSetID code and nothing else in the kernel.

  The changes to SafeSetID internally allow for setting up GID
  transition security policies, as already existed for UIDs"

* tag 'safesetid-5.10' of git://github.com/micah-morton/linux:
  LSM: SafeSetID: Fix warnings reported by test bot
  LSM: SafeSetID: Add GID security policy handling
  LSM: Signal to SafeSetID when setting group IDs
2020-10-25 10:45:26 -07:00
Linus Torvalds 91f28da8c9 random32: make prandom_u32() less predictable
This is the cleanup of the latest series of prandom_u32 experimentations
 consisting in using SipHash instead of Tausworthe to produce the randoms
 used by the network stack. The changes to the files were kept minimal,
 and the controversial commit that used to take noise from the fast_pool
 (f227e3ec3b) was reverted. Instead, a dedicated "net_rand_noise" per_cpu
 variable is fed from various sources of activities (networking, scheduling)
 to perturb the SipHash state using fast, non-trivially predictable data,
 instead of keeping it fully deterministic. The goal is essentially to make
 any occasional memory leakage or brute-force attempt useless.
 
 The resulting code was verified to be very slightly faster on x86_64 than
 what is was with the controversial commit above, though this remains barely
 above measurement noise. It was also tested on i386 and arm, and build-
 tested only on arm64.
 
 The whole discussion around this is archived here:
   https://lore.kernel.org/netdev/20200808152628.GA27941@SDF.ORG/
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Merge tag '20201024-v4-5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/wtarreau/prandom

Pull random32 updates from Willy Tarreau:
 "Make prandom_u32() less predictable.

  This is the cleanup of the latest series of prandom_u32
  experimentations consisting in using SipHash instead of Tausworthe to
  produce the randoms used by the network stack.

  The changes to the files were kept minimal, and the controversial
  commit that used to take noise from the fast_pool (f227e3ec3b) was
  reverted. Instead, a dedicated "net_rand_noise" per_cpu variable is
  fed from various sources of activities (networking, scheduling) to
  perturb the SipHash state using fast, non-trivially predictable data,
  instead of keeping it fully deterministic. The goal is essentially to
  make any occasional memory leakage or brute-force attempt useless.

  The resulting code was verified to be very slightly faster on x86_64
  than what is was with the controversial commit above, though this
  remains barely above measurement noise. It was also tested on i386 and
  arm, and build- tested only on arm64"

Link: https://lore.kernel.org/netdev/20200808152628.GA27941@SDF.ORG/

* tag '20201024-v4-5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/wtarreau/prandom:
  random32: add a selftest for the prandom32 code
  random32: add noise from network and scheduling activity
  random32: make prandom_u32() output unpredictable
2020-10-25 10:40:08 -07:00
Linus Torvalds 1b307ac870 dma-mapping fixes for 5.10:
- document the new document dma_{alloc,free}_pages API
  - two fixups for the dma-mapping.h split
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Merge tag 'dma-mapping-5.10-1' of git://git.infradead.org/users/hch/dma-mapping

Pull dma-mapping fixes from Christoph Hellwig:

 - document the new dma_{alloc,free}_pages() API

 - two fixups for the dma-mapping.h split

* tag 'dma-mapping-5.10-1' of git://git.infradead.org/users/hch/dma-mapping:
  dma-mapping: document dma_{alloc,free}_pages
  dma-mapping: move more functions to dma-map-ops.h
  ARM/sa1111: add a missing include of dma-map-ops.h
2020-10-24 12:17:05 -07:00
Willy Tarreau 3744741ada random32: add noise from network and scheduling activity
With the removal of the interrupt perturbations in previous random32
change (random32: make prandom_u32() output unpredictable), the PRNG
has become 100% deterministic again. While SipHash is expected to be
way more robust against brute force than the previous Tausworthe LFSR,
there's still the risk that whoever has even one temporary access to
the PRNG's internal state is able to predict all subsequent draws till
the next reseed (roughly every minute). This may happen through a side
channel attack or any data leak.

This patch restores the spirit of commit f227e3ec3b ("random32: update
the net random state on interrupt and activity") in that it will perturb
the internal PRNG's statee using externally collected noise, except that
it will not pick that noise from the random pool's bits nor upon
interrupt, but will rather combine a few elements along the Tx path
that are collectively hard to predict, such as dev, skb and txq
pointers, packet length and jiffies values. These ones are combined
using a single round of SipHash into a single long variable that is
mixed with the net_rand_state upon each invocation.

The operation was inlined because it produces very small and efficient
code, typically 3 xor, 2 add and 2 rol. The performance was measured
to be the same (even very slightly better) than before the switch to
SipHash; on a 6-core 12-thread Core i7-8700k equipped with a 40G NIC
(i40e), the connection rate dropped from 556k/s to 555k/s while the
SYN cookie rate grew from 5.38 Mpps to 5.45 Mpps.

Link: https://lore.kernel.org/netdev/20200808152628.GA27941@SDF.ORG/
Cc: George Spelvin <lkml@sdf.org>
Cc: Amit Klein <aksecurity@gmail.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: "Jason A. Donenfeld" <Jason@zx2c4.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: tytso@mit.edu
Cc: Florian Westphal <fw@strlen.de>
Cc: Marc Plumb <lkml.mplumb@gmail.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2020-10-24 20:21:57 +02:00
George Spelvin c51f8f88d7 random32: make prandom_u32() output unpredictable
Non-cryptographic PRNGs may have great statistical properties, but
are usually trivially predictable to someone who knows the algorithm,
given a small sample of their output.  An LFSR like prandom_u32() is
particularly simple, even if the sample is widely scattered bits.

It turns out the network stack uses prandom_u32() for some things like
random port numbers which it would prefer are *not* trivially predictable.
Predictability led to a practical DNS spoofing attack.  Oops.

This patch replaces the LFSR with a homebrew cryptographic PRNG based
on the SipHash round function, which is in turn seeded with 128 bits
of strong random key.  (The authors of SipHash have *not* been consulted
about this abuse of their algorithm.)  Speed is prioritized over security;
attacks are rare, while performance is always wanted.

Replacing all callers of prandom_u32() is the quick fix.
Whether to reinstate a weaker PRNG for uses which can tolerate it
is an open question.

Commit f227e3ec3b ("random32: update the net random state on interrupt
and activity") was an earlier attempt at a solution.  This patch replaces
it.

Reported-by: Amit Klein <aksecurity@gmail.com>
Cc: Willy Tarreau <w@1wt.eu>
Cc: Eric Dumazet <edumazet@google.com>
Cc: "Jason A. Donenfeld" <Jason@zx2c4.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: tytso@mit.edu
Cc: Florian Westphal <fw@strlen.de>
Cc: Marc Plumb <lkml.mplumb@gmail.com>
Fixes: f227e3ec3b ("random32: update the net random state on interrupt and activity")
Signed-off-by: George Spelvin <lkml@sdf.org>
Link: https://lore.kernel.org/netdev/20200808152628.GA27941@SDF.ORG/
[ willy: partial reversal of f227e3ec3b5c; moved SIPROUND definitions
  to prandom.h for later use; merged George's prandom_seed() proposal;
  inlined siprand_u32(); replaced the net_rand_state[] array with 4
  members to fix a build issue; cosmetic cleanups to make checkpatch
  happy; fixed RANDOM32_SELFTEST build ]
Signed-off-by: Willy Tarreau <w@1wt.eu>
2020-10-24 20:21:57 +02:00
Linus Torvalds a5e5c274c9 ring-buffer fix
The success return value of ring_buffer_resize() is stated to be zero,
 and checked that way. But it is incorrectly returning the size allocated.
 
 Also, a fix to a comment.
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Merge tag 'trace-v5.10-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing ring-buffer fix from Steven Rostedt:
 "The success return value of ring_buffer_resize() is stated to be
  zero and checked that way.

  But it was incorrectly returning the size allocated.

  Also, a fix to a comment"

* tag 'trace-v5.10-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  ring-buffer: Update the description for ring_buffer_wait
  ring-buffer: Return 0 on success from ring_buffer_resize()
2020-10-23 17:09:38 -07:00
Linus Torvalds 41f762a15a More power management updates for 5.10-rc1
- Move the AVS drivers to new platform-specific locations and get
    rid of the drivers/power/avs directory (Ulf Hansson).
 
  - Add on/off notifiers and idle state accounting support to the
    generic power domains (genpd) framework (Ulf Hansson, Lina Iyer).
 
  - Ulf will maintain the PM domain part of cpuidle-psci (Ulf Hansson).
 
  - Make intel_idle disregard ACPI _CST if it cannot use the data
    returned by that method (Mel Gorman).
 
  - Modify intel_pstate to avoid leaving useless sysfs directory
    structure behind if it cannot be registered (Chen Yu).
 
  - Fix domain detection in the RAPL power capping driver and prevent
    it from failing to enumerate the Psys RAPL domain (Zhang Rui).
 
  - Allow acpi-cpufreq to use ACPI _PSD information with Family 19 and
    later AMD chips (Wei Huang).
 
  - Update the driver assumptions comment in intel_idle and fix a
    kerneldoc comment in the runtime PM framework (Alexander Monakov,
    Bean Huo).
 
  - Avoid unnecessary resets of the cached frequency in the schedutil
    cpufreq governor to reduce overhead (Wei Wang).
 
  - Clean up the cpufreq core a bit (Viresh Kumar).
 
  - Make assorted minor janitorial changes (Daniel Lezcano, Geert
    Uytterhoeven, Hubert Jasudowicz, Tom Rix).
 
  - Clean up and optimize the cpupower utility somewhat (Colin Ian
    King, Martin Kaistra).
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Merge tag 'pm-5.10-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull more power management updates from Rafael Wysocki:
 "First of all, the adaptive voltage scaling (AVS) drivers go to new
  platform-specific locations as planned (this part was reported to have
  merge conflicts against the new arm-soc updates in linux-next).

  In addition to that, there are some fixes (intel_idle, intel_pstate,
  RAPL, acpi_cpufreq), the addition of on/off notifiers and idle state
  accounting support to the generic power domains (genpd) code and some
  janitorial changes all over.

  Specifics:

   - Move the AVS drivers to new platform-specific locations and get rid
     of the drivers/power/avs directory (Ulf Hansson).

   - Add on/off notifiers and idle state accounting support to the
     generic power domains (genpd) framework (Ulf Hansson, Lina Iyer).

   - Ulf will maintain the PM domain part of cpuidle-psci (Ulf Hansson).

   - Make intel_idle disregard ACPI _CST if it cannot use the data
     returned by that method (Mel Gorman).

   - Modify intel_pstate to avoid leaving useless sysfs directory
     structure behind if it cannot be registered (Chen Yu).

   - Fix domain detection in the RAPL power capping driver and prevent
     it from failing to enumerate the Psys RAPL domain (Zhang Rui).

   - Allow acpi-cpufreq to use ACPI _PSD information with Family 19 and
     later AMD chips (Wei Huang).

   - Update the driver assumptions comment in intel_idle and fix a
     kerneldoc comment in the runtime PM framework (Alexander Monakov,
     Bean Huo).

   - Avoid unnecessary resets of the cached frequency in the schedutil
     cpufreq governor to reduce overhead (Wei Wang).

   - Clean up the cpufreq core a bit (Viresh Kumar).

   - Make assorted minor janitorial changes (Daniel Lezcano, Geert
     Uytterhoeven, Hubert Jasudowicz, Tom Rix).

   - Clean up and optimize the cpupower utility somewhat (Colin Ian
     King, Martin Kaistra)"

* tag 'pm-5.10-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (23 commits)
  PM: sleep: remove unreachable break
  PM: AVS: Drop the avs directory and the corresponding Kconfig
  PM: AVS: qcom-cpr: Move the driver to the qcom specific drivers
  PM: runtime: Fix typo in pm_runtime_set_active() helper comment
  PM: domains: Fix build error for genpd notifiers
  powercap: Fix typo in Kconfig "Plance" -> "Plane"
  cpufreq: schedutil: restore cached freq when next_f is not changed
  acpi-cpufreq: Honor _PSD table setting on new AMD CPUs
  PM: AVS: smartreflex Move driver to soc specific drivers
  PM: AVS: rockchip-io: Move the driver to the rockchip specific drivers
  PM: domains: enable domain idle state accounting
  PM: domains: Add curly braces to delimit comment + statement block
  PM: domains: Add support for PM domain on/off notifiers for genpd
  powercap/intel_rapl: enumerate Psys RAPL domain together with package RAPL domain
  powercap/intel_rapl: Fix domain detection
  intel_idle: Ignore _CST if control cannot be taken from the platform
  cpuidle: Remove pointless stub
  intel_idle: mention assumption that WBINVD is not needed
  MAINTAINERS: Add section for cpuidle-psci PM domain
  cpufreq: intel_pstate: Delete intel_pstate sysfs if failed to register the driver
  ...
2020-10-23 16:27:03 -07:00
Linus Torvalds 3cb12d27ff Fixes for 5.10-rc1 from the networking tree:
Cross-tree/merge window issues:
 
  - rtl8150: don't incorrectly assign random MAC addresses; fix late
    in the 5.9 cycle started depending on a return code from
    a function which changed with the 5.10 PR from the usb subsystem
 
 Current release - regressions:
 
  - Revert "virtio-net: ethtool configurable RXCSUM", it was causing
    crashes at probe when control vq was not negotiated/available
 
 Previous releases - regressions:
 
  - ixgbe: fix probing of multi-port 10 Gigabit Intel NICs with an MDIO
    bus, only first device would be probed correctly
 
  - nexthop: Fix performance regression in nexthop deletion by
    effectively switching from recently added synchronize_rcu()
    to synchronize_rcu_expedited()
 
  - netsec: ignore 'phy-mode' device property on ACPI systems;
    the property is not populated correctly by the firmware,
    but firmware configures the PHY so just keep boot settings
 
 Previous releases - always broken:
 
  - tcp: fix to update snd_wl1 in bulk receiver fast path, addressing
    bulk transfers getting "stuck"
 
  - icmp: randomize the global rate limiter to prevent attackers from
    getting useful signal
 
  - r8169: fix operation under forced interrupt threading, make the
    driver always use hard irqs, even on RT, given the handler is
    light and only wants to schedule napi (and do so through
    a _irqoff() variant, preferably)
 
  - bpf: Enforce pointer id generation for all may-be-null register
    type to avoid pointers erroneously getting marked as null-checked
 
  - tipc: re-configure queue limit for broadcast link
 
  - net/sched: act_tunnel_key: fix OOB write in case of IPv6 ERSPAN
    tunnels
 
  - fix various issues in chelsio inline tls driver
 
 Misc:
 
  - bpf: improve just-added bpf_redirect_neigh() helper api to support
    supplying nexthop by the caller - in case BPF program has already
    done a lookup we can avoid doing another one
 
  - remove unnecessary break statements
 
  - make MCTCP not select IPV6, but rather depend on it
 
 Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'net-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

Pull networking fixes from Jakub Kicinski:
 "Cross-tree/merge window issues:

   - rtl8150: don't incorrectly assign random MAC addresses; fix late in
     the 5.9 cycle started depending on a return code from a function
     which changed with the 5.10 PR from the usb subsystem

  Current release regressions:

   - Revert "virtio-net: ethtool configurable RXCSUM", it was causing
     crashes at probe when control vq was not negotiated/available

  Previous release regressions:

   - ixgbe: fix probing of multi-port 10 Gigabit Intel NICs with an MDIO
     bus, only first device would be probed correctly

   - nexthop: Fix performance regression in nexthop deletion by
     effectively switching from recently added synchronize_rcu() to
     synchronize_rcu_expedited()

   - netsec: ignore 'phy-mode' device property on ACPI systems; the
     property is not populated correctly by the firmware, but firmware
     configures the PHY so just keep boot settings

  Previous releases - always broken:

   - tcp: fix to update snd_wl1 in bulk receiver fast path, addressing
     bulk transfers getting "stuck"

   - icmp: randomize the global rate limiter to prevent attackers from
     getting useful signal

   - r8169: fix operation under forced interrupt threading, make the
     driver always use hard irqs, even on RT, given the handler is light
     and only wants to schedule napi (and do so through a _irqoff()
     variant, preferably)

   - bpf: Enforce pointer id generation for all may-be-null register
     type to avoid pointers erroneously getting marked as null-checked

   - tipc: re-configure queue limit for broadcast link

   - net/sched: act_tunnel_key: fix OOB write in case of IPv6 ERSPAN
     tunnels

   - fix various issues in chelsio inline tls driver

  Misc:

   - bpf: improve just-added bpf_redirect_neigh() helper api to support
     supplying nexthop by the caller - in case BPF program has already
     done a lookup we can avoid doing another one

   - remove unnecessary break statements

   - make MCTCP not select IPV6, but rather depend on it"

* tag 'net-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (62 commits)
  tcp: fix to update snd_wl1 in bulk receiver fast path
  net: Properly typecast int values to set sk_max_pacing_rate
  netfilter: nf_fwd_netdev: clear timestamp in forwarding path
  ibmvnic: save changed mac address to adapter->mac_addr
  selftests: mptcp: depends on built-in IPv6
  Revert "virtio-net: ethtool configurable RXCSUM"
  rtnetlink: fix data overflow in rtnl_calcit()
  net: ethernet: mtk-star-emac: select REGMAP_MMIO
  net: hdlc_raw_eth: Clear the IFF_TX_SKB_SHARING flag after calling ether_setup
  net: hdlc: In hdlc_rcv, check to make sure dev is an HDLC device
  bpf, libbpf: Guard bpf inline asm from bpf_tail_call_static
  bpf, selftests: Extend test_tc_redirect to use modified bpf_redirect_neigh()
  bpf: Fix bpf_redirect_neigh helper api to support supplying nexthop
  mptcp: depends on IPV6 but not as a module
  sfc: move initialisation of efx->filter_sem to efx_init_struct()
  mpls: load mpls_gso after mpls_iptunnel
  net/sched: act_tunnel_key: fix OOB write in case of IPv6 ERSPAN tunnels
  net/sched: act_gate: Unlock ->tcfa_lock in tc_setup_flow_action()
  net: dsa: bcm_sf2: make const array static, makes object smaller
  mptcp: MPTCP_IPV6 should depend on IPV6 instead of selecting it
  ...
2020-10-23 12:05:49 -07:00
Linus Torvalds 4a22709e21 arch-cleanup-2020-10-22
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Merge tag 'arch-cleanup-2020-10-22' of git://git.kernel.dk/linux-block

Pull arch task_work cleanups from Jens Axboe:
 "Two cleanups that don't fit other categories:

   - Finally get the task_work_add() cleanup done properly, so we don't
     have random 0/1/false/true/TWA_SIGNAL confusing use cases. Updates
     all callers, and also fixes up the documentation for
     task_work_add().

   - While working on some TIF related changes for 5.11, this
     TIF_NOTIFY_RESUME cleanup fell out of that. Remove some arch
     duplication for how that is handled"

* tag 'arch-cleanup-2020-10-22' of git://git.kernel.dk/linux-block:
  task_work: cleanup notification modes
  tracehook: clear TIF_NOTIFY_RESUME in tracehook_notify_resume()
2020-10-23 10:06:38 -07:00
Linus Torvalds 746b25b1aa Kbuild updates for v5.10
- Support 'make compile_commands.json' to generate the compilation
    database more easily, avoiding stale entries
 
  - Support 'make clang-analyzer' and 'make clang-tidy' for static checks
    using clang-tidy
 
  - Preprocess scripts/modules.lds.S to allow CONFIG options in the module
    linker script
 
  - Drop cc-option tests from compiler flags supported by our minimal
    GCC/Clang versions
 
  - Use always 12-digits commit hash for CONFIG_LOCALVERSION_AUTO=y
 
  - Use sha1 build id for both BFD linker and LLD
 
  - Improve deb-pkg for reproducible builds and rootless builds
 
  - Remove stale, useless scripts/namespace.pl
 
  - Turn -Wreturn-type warning into error
 
  - Fix build error of deb-pkg when CONFIG_MODULES=n
 
  - Replace 'hostname' command with more portable 'uname -n'
 
  - Various Makefile cleanups
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Merge tag 'kbuild-v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

 - Support 'make compile_commands.json' to generate the compilation
   database more easily, avoiding stale entries

 - Support 'make clang-analyzer' and 'make clang-tidy' for static checks
   using clang-tidy

 - Preprocess scripts/modules.lds.S to allow CONFIG options in the
   module linker script

 - Drop cc-option tests from compiler flags supported by our minimal
   GCC/Clang versions

 - Use always 12-digits commit hash for CONFIG_LOCALVERSION_AUTO=y

 - Use sha1 build id for both BFD linker and LLD

 - Improve deb-pkg for reproducible builds and rootless builds

 - Remove stale, useless scripts/namespace.pl

 - Turn -Wreturn-type warning into error

 - Fix build error of deb-pkg when CONFIG_MODULES=n

 - Replace 'hostname' command with more portable 'uname -n'

 - Various Makefile cleanups

* tag 'kbuild-v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (34 commits)
  kbuild: Use uname for LINUX_COMPILE_HOST detection
  kbuild: Only add -fno-var-tracking-assignments for old GCC versions
  kbuild: remove leftover comment for filechk utility
  treewide: remove DISABLE_LTO
  kbuild: deb-pkg: clean up package name variables
  kbuild: deb-pkg: do not build linux-headers package if CONFIG_MODULES=n
  kbuild: enforce -Werror=return-type
  scripts: remove namespace.pl
  builddeb: Add support for all required debian/rules targets
  builddeb: Enable rootless builds
  builddeb: Pass -n to gzip for reproducible packages
  kbuild: split the build log of kallsyms
  kbuild: explicitly specify the build id style
  scripts/setlocalversion: make git describe output more reliable
  kbuild: remove cc-option test of -Werror=date-time
  kbuild: remove cc-option test of -fno-stack-check
  kbuild: remove cc-option test of -fno-strict-overflow
  kbuild: move CFLAGS_{KASAN,UBSAN,KCSAN} exports to relevant Makefiles
  kbuild: remove redundant CONFIG_KASAN check from scripts/Makefile.kasan
  kbuild: do not create built-in objects for external module builds
  ...
2020-10-22 13:13:57 -07:00
Linus Torvalds 2b71482060 Modules updates for v5.10
Summary of modules changes for the 5.10 merge window:
 
 - Code cleanups. More informative error messages and statically
   initialize init_free_wq to avoid a workqueue warning.
 
 Signed-off-by: Jessica Yu <jeyu@kernel.org>
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Merge tag 'modules-for-v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux

Pull modules updates from Jessica Yu:
 "Code cleanups: more informative error messages and statically
  initialize init_free_wq to avoid a workqueue warning"

* tag 'modules-for-v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
  module: statically initialize init section freeing data
  module: Add more error message for failed kernel module loading
2020-10-22 13:08:57 -07:00
Linus Torvalds f56e65dff6 Merge branch 'work.set_fs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull initial set_fs() removal from Al Viro:
 "Christoph's set_fs base series + fixups"

* 'work.set_fs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  fs: Allow a NULL pos pointer to __kernel_read
  fs: Allow a NULL pos pointer to __kernel_write
  powerpc: remove address space overrides using set_fs()
  powerpc: use non-set_fs based maccess routines
  x86: remove address space overrides using set_fs()
  x86: make TASK_SIZE_MAX usable from assembly code
  x86: move PAGE_OFFSET, TASK_SIZE & friends to page_{32,64}_types.h
  lkdtm: remove set_fs-based tests
  test_bitmap: remove user bitmap tests
  uaccess: add infrastructure for kernel builds with set_fs()
  fs: don't allow splice read/write without explicit ops
  fs: don't allow kernel reads and writes without iter ops
  sysctl: Convert to iter interfaces
  proc: add a read_iter method to proc proc_ops
  proc: cleanup the compat vs no compat file ops
  proc: remove a level of indentation in proc_get_inode
2020-10-22 09:59:21 -07:00
Qiujun Huang e1981f75d3 ring-buffer: Update the description for ring_buffer_wait
The function changed at some point, but the description was not
updated.

Link: https://lkml.kernel.org/r/20201017095246.5170-1-hqjagain@gmail.com

Signed-off-by: Qiujun Huang <hqjagain@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-10-22 11:26:26 -04:00
Qiujun Huang 0a1754b2a9 ring-buffer: Return 0 on success from ring_buffer_resize()
We don't need to check the new buffer size, and the return value
had confused resize_buffer_duplicate_size().
...
	ret = ring_buffer_resize(trace_buf->buffer,
		per_cpu_ptr(size_buf->data,cpu_id)->entries, cpu_id);
	if (ret == 0)
		per_cpu_ptr(trace_buf->data, cpu_id)->entries =
			per_cpu_ptr(size_buf->data, cpu_id)->entries;
...

Link: https://lkml.kernel.org/r/20201019142242.11560-1-hqjagain@gmail.com

Cc: stable@vger.kernel.org
Fixes: d60da506cb ("tracing: Add a resize function to make one buffer equivalent to another buffer")
Signed-off-by: Qiujun Huang <hqjagain@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-10-22 11:24:10 -04:00
Peter Zijlstra f8e48a3dca lockdep: Fix preemption WARN for spurious IRQ-enable
It is valid (albeit uncommon) to call local_irq_enable() without first
having called local_irq_disable(). In this case we enter
lockdep_hardirqs_on*() with IRQs enabled and trip a preemption warning
for using __this_cpu_read().

Use this_cpu_read() instead to avoid the warning.

Fixes: 4d004099a6 ("lockdep: Fix lockdep recursion")
Reported-by: syzbot+53f8ce8bbc07924b6417@syzkaller.appspotmail.com
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
2020-10-22 12:37:22 +02:00
Sami Tolvanen 0f6372e522 treewide: remove DISABLE_LTO
This change removes all instances of DISABLE_LTO from
Makefiles, as they are currently unused, and the preferred
method of disabling LTO is to filter out the flags instead.

Note added by Masahiro Yamada:
DISABLE_LTO was added as preparation for GCC LTO, but GCC LTO was
not pulled into the mainline. (https://lkml.org/lkml/2014/4/8/272)

Suggested-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-10-21 00:28:53 +09:00
Andrei Vagin c2f7d08ccc futex: Adjust absolute futex timeouts with per time namespace offset
For all commands except FUTEX_WAIT, the timeout is interpreted as an
absolute value. This absolute value is inside the task's time namespace and
has to be converted to the host's time.

Fixes: 5a590f35ad ("posix-clocks: Wire up clock_gettime() with timens offsets")
Reported-by: Hans van der Laan <j.h.vanderlaan@student.utwente.nl>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Dmitry Safonov <0x7f454c46@gmail.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20201015160020.293748-1-avagin@gmail.com
2020-10-20 17:02:57 +02:00
Christoph Hellwig 695cebe58d dma-mapping: move more functions to dma-map-ops.h
Due to a mismerge a bunch of prototypes that should have moved to
dma-map-ops.h are still in dma-mapping.h, fix that up.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-10-20 10:41:07 +02:00
Martin KaFai Lau 93c230e3f5 bpf: Enforce id generation for all may-be-null register type
The commit af7ec13833 ("bpf: Add bpf_skc_to_tcp6_sock() helper")
introduces RET_PTR_TO_BTF_ID_OR_NULL and
the commit eaa6bcb71e ("bpf: Introduce bpf_per_cpu_ptr()")
introduces RET_PTR_TO_MEM_OR_BTF_ID_OR_NULL.
Note that for RET_PTR_TO_MEM_OR_BTF_ID_OR_NULL, the reg0->type
could become PTR_TO_MEM_OR_NULL which is not covered by
BPF_PROBE_MEM.

The BPF_REG_0 will then hold a _OR_NULL pointer type. This _OR_NULL
pointer type requires the bpf program to explicitly do a NULL check first.
After NULL check, the verifier will mark all registers having
the same reg->id as safe to use.  However, the reg->id
is not set for those new _OR_NULL return types.  One of the ways
that may be wrong is, checking NULL for one btf_id typed pointer will
end up validating all other btf_id typed pointers because
all of them have id == 0.  The later tests will exercise
this path.

To fix it and also avoid similar issue in the future, this patch
moves the id generation logic out of each individual RET type
test in check_helper_call().  Instead, it does one
reg_type_may_be_null() test and then do the id generation
if needed.

This patch also adds a WARN_ON_ONCE in mark_ptr_or_null_reg()
to catch future breakage.

The _OR_NULL pointer usage in the bpf_iter_reg.ctx_arg_info is
fine because it just happens that the existing id generation after
check_ctx_access() has covered it.  It is also using the
reg_type_may_be_null() to decide if id generation is needed or not.

Fixes: af7ec13833 ("bpf: Add bpf_skc_to_tcp6_sock() helper")
Fixes: eaa6bcb71e ("bpf: Introduce bpf_per_cpu_ptr()")
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20201019194212.1050855-1-kafai@fb.com
2020-10-19 15:57:42 -07:00
Tom Rix 76702a2e72 bpf: Remove unneeded break
A break is not needed if it is preceded by a return.

Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20201019173846.1021-1-trix@redhat.com
2020-10-19 20:40:21 +02:00
Wei Wang 0070ea2962 cpufreq: schedutil: restore cached freq when next_f is not changed
We have the raw cached freq to reduce the chance in calling cpufreq
driver where it could be costly in some arch/SoC.

Currently, the raw cached freq is reset in sugov_update_single() when
it avoids frequency reduction (which is not desirable sometimes), but
it is better to restore the previous value of it in that case,
because it may not change in the next cycle and it is not necessary
to change the CPU frequency then.

Adapted from https://android-review.googlesource.com/1352810/

Signed-off-by: Wei Wang <wvw@google.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
[ rjw: Subject edit and changelog rewrite ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-10-19 17:38:16 +02:00
Linus Torvalds 41eea65e2a Merge tag 'core-rcu-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RCU changes from Ingo Molnar:

 - Debugging for smp_call_function()

 - RT raw/non-raw lock ordering fixes

 - Strict grace periods for KASAN

 - New smp_call_function() torture test

 - Torture-test updates

 - Documentation updates

 - Miscellaneous fixes

[ This doesn't actually pull the tag - I've dropped the last merge from
  the RCU branch due to questions about the series.   - Linus ]

* tag 'core-rcu-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (77 commits)
  smp: Make symbol 'csd_bug_count' static
  kernel/smp: Provide CSD lock timeout diagnostics
  smp: Add source and destination CPUs to __call_single_data
  rcu: Shrink each possible cpu krcp
  rcu/segcblist: Prevent useless GP start if no CBs to accelerate
  torture: Add gdb support
  rcutorture: Allow pointer leaks to test diagnostic code
  rcutorture: Hoist OOM registry up one level
  refperf: Avoid null pointer dereference when buf fails to allocate
  rcutorture: Properly synchronize with OOM notifier
  rcutorture: Properly set rcu_fwds for OOM handling
  torture: Add kvm.sh --help and update help message
  rcutorture: Add CONFIG_PROVE_RCU_LIST to TREE05
  torture: Update initrd documentation
  rcutorture: Replace HTTP links with HTTPS ones
  locktorture: Make function torture_percpu_rwsem_init() static
  torture: document --allcpus argument added to the kvm.sh script
  rcutorture: Output number of elapsed grace periods
  rcutorture: Remove KCSAN stubs
  rcu: Remove unused "cpu" parameter from rcu_report_qs_rdp()
  ...
2020-10-18 14:34:50 -07:00
Minchan Kim ecb8ac8b1f mm/madvise: introduce process_madvise() syscall: an external memory hinting API
There is usecase that System Management Software(SMS) want to give a
memory hint like MADV_[COLD|PAGEEOUT] to other processes and in the
case of Android, it is the ActivityManagerService.

The information required to make the reclaim decision is not known to the
app.  Instead, it is known to the centralized userspace
daemon(ActivityManagerService), and that daemon must be able to initiate
reclaim on its own without any app involvement.

To solve the issue, this patch introduces a new syscall
process_madvise(2).  It uses pidfd of an external process to give the
hint.  It also supports vector address range because Android app has
thousands of vmas due to zygote so it's totally waste of CPU and power if
we should call the syscall one by one for each vma.(With testing 2000-vma
syscall vs 1-vector syscall, it showed 15% performance improvement.  I
think it would be bigger in real practice because the testing ran very
cache friendly environment).

Another potential use case for the vector range is to amortize the cost
ofTLB shootdowns for multiple ranges when using MADV_DONTNEED; this could
benefit users like TCP receive zerocopy and malloc implementations.  In
future, we could find more usecases for other advises so let's make it
happens as API since we introduce a new syscall at this moment.  With
that, existing madvise(2) user could replace it with process_madvise(2)
with their own pid if they want to have batch address ranges support
feature.

ince it could affect other process's address range, only privileged
process(PTRACE_MODE_ATTACH_FSCREDS) or something else(e.g., being the same
UID) gives it the right to ptrace the process could use it successfully.
The flag argument is reserved for future use if we need to extend the API.

I think supporting all hints madvise has/will supported/support to
process_madvise is rather risky.  Because we are not sure all hints make
sense from external process and implementation for the hint may rely on
the caller being in the current context so it could be error-prone.  Thus,
I just limited hints as MADV_[COLD|PAGEOUT] in this patch.

If someone want to add other hints, we could hear the usecase and review
it for each hint.  It's safer for maintenance rather than introducing a
buggy syscall but hard to fix it later.

So finally, the API is as follows,

      ssize_t process_madvise(int pidfd, const struct iovec *iovec,
                unsigned long vlen, int advice, unsigned int flags);

    DESCRIPTION
      The process_madvise() system call is used to give advice or directions
      to the kernel about the address ranges from external process as well as
      local process. It provides the advice to address ranges of process
      described by iovec and vlen. The goal of such advice is to improve
      system or application performance.

      The pidfd selects the process referred to by the PID file descriptor
      specified in pidfd. (See pidofd_open(2) for further information)

      The pointer iovec points to an array of iovec structures, defined in
      <sys/uio.h> as:

        struct iovec {
            void *iov_base;         /* starting address */
            size_t iov_len;         /* number of bytes to be advised */
        };

      The iovec describes address ranges beginning at address(iov_base)
      and with size length of bytes(iov_len).

      The vlen represents the number of elements in iovec.

      The advice is indicated in the advice argument, which is one of the
      following at this moment if the target process specified by pidfd is
      external.

        MADV_COLD
        MADV_PAGEOUT

      Permission to provide a hint to external process is governed by a
      ptrace access mode PTRACE_MODE_ATTACH_FSCREDS check; see ptrace(2).

      The process_madvise supports every advice madvise(2) has if target
      process is in same thread group with calling process so user could
      use process_madvise(2) to extend existing madvise(2) to support
      vector address ranges.

    RETURN VALUE
      On success, process_madvise() returns the number of bytes advised.
      This return value may be less than the total number of requested
      bytes, if an error occurred. The caller should check return value
      to determine whether a partial advice occurred.

FAQ:

Q.1 - Why does any external entity have better knowledge?

Quote from Sandeep

"For Android, every application (including the special SystemServer)
are forked from Zygote.  The reason of course is to share as many
libraries and classes between the two as possible to benefit from the
preloading during boot.

After applications start, (almost) all of the APIs end up calling into
this SystemServer process over IPC (binder) and back to the
application.

In a fully running system, the SystemServer monitors every single
process periodically to calculate their PSS / RSS and also decides
which process is "important" to the user for interactivity.

So, because of how these processes start _and_ the fact that the
SystemServer is looping to monitor each process, it does tend to *know*
which address range of the application is not used / useful.

Besides, we can never rely on applications to clean things up
themselves.  We've had the "hey app1, the system is low on memory,
please trim your memory usage down" notifications for a long time[1].
They rely on applications honoring the broadcasts and very few do.

So, if we want to avoid the inevitable killing of the application and
restarting it, some way to be able to tell the OS about unimportant
memory in these applications will be useful.

- ssp

Q.2 - How to guarantee the race(i.e., object validation) between when
giving a hint from an external process and get the hint from the target
process?

process_madvise operates on the target process's address space as it
exists at the instant that process_madvise is called.  If the space
target process can run between the time the process_madvise process
inspects the target process address space and the time that
process_madvise is actually called, process_madvise may operate on
memory regions that the calling process does not expect.  It's the
responsibility of the process calling process_madvise to close this
race condition.  For example, the calling process can suspend the
target process with ptrace, SIGSTOP, or the freezer cgroup so that it
doesn't have an opportunity to change its own address space before
process_madvise is called.  Another option is to operate on memory
regions that the caller knows a priori will be unchanged in the target
process.  Yet another option is to accept the race for certain
process_madvise calls after reasoning that mistargeting will do no
harm.  The suggested API itself does not provide synchronization.  It
also apply other APIs like move_pages, process_vm_write.

The race isn't really a problem though.  Why is it so wrong to require
that callers do their own synchronization in some manner?  Nobody
objects to write(2) merely because it's possible for two processes to
open the same file and clobber each other's writes --- instead, we tell
people to use flock or something.  Think about mmap.  It never
guarantees newly allocated address space is still valid when the user
tries to access it because other threads could unmap the memory right
before.  That's where we need synchronization by using other API or
design from userside.  It shouldn't be part of API itself.  If someone
needs more fine-grained synchronization rather than process level,
there were two ideas suggested - cookie[2] and anon-fd[3].  Both are
applicable via using last reserved argument of the API but I don't
think it's necessary right now since we have already ways to prevent
the race so don't want to add additional complexity with more
fine-grained optimization model.

To make the API extend, it reserved an unsigned long as last argument
so we could support it in future if someone really needs it.

Q.3 - Why doesn't ptrace work?

Injecting an madvise in the target process using ptrace would not work
for us because such injected madvise would have to be executed by the
target process, which means that process would have to be runnable and
that creates the risk of the abovementioned race and hinting a wrong
VMA.  Furthermore, we want to act the hint in caller's context, not the
callee's, because the callee is usually limited in cpuset/cgroups or
even freezed state so they can't act by themselves quick enough, which
causes more thrashing/kill.  It doesn't work if the target process are
ptraced(e.g., strace, debugger, minidump) because a process can have at
most one ptracer.

[1] https://developer.android.com/topic/performance/memory"

[2] process_getinfo for getting the cookie which is updated whenever
    vma of process address layout are changed - Daniel Colascione -
    https://lore.kernel.org/lkml/20190520035254.57579-1-minchan@kernel.org/T/#m7694416fd179b2066a2c62b5b139b14e3894e224

[3] anonymous fd which is used for the object(i.e., address range)
    validation - Michal Hocko -
    https://lore.kernel.org/lkml/20200120112722.GY18451@dhcp22.suse.cz/

[minchan@kernel.org: fix process_madvise build break for arm64]
  Link: http://lkml.kernel.org/r/20200303145756.GA219683@google.com
[minchan@kernel.org: fix build error for mips of process_madvise]
  Link: http://lkml.kernel.org/r/20200508052517.GA197378@google.com
[akpm@linux-foundation.org: fix patch ordering issue]
[akpm@linux-foundation.org: fix arm64 whoops]
[minchan@kernel.org: make process_madvise() vlen arg have type size_t, per Florian]
[akpm@linux-foundation.org: fix i386 build]
[sfr@canb.auug.org.au: fix syscall numbering]
  Link: https://lkml.kernel.org/r/20200905142639.49fc3f1a@canb.auug.org.au
[sfr@canb.auug.org.au: madvise.c needs compat.h]
  Link: https://lkml.kernel.org/r/20200908204547.285646b4@canb.auug.org.au
[minchan@kernel.org: fix mips build]
  Link: https://lkml.kernel.org/r/20200909173655.GC2435453@google.com
[yuehaibing@huawei.com: remove duplicate header which is included twice]
  Link: https://lkml.kernel.org/r/20200915121550.30584-1-yuehaibing@huawei.com
[minchan@kernel.org: do not use helper functions for process_madvise]
  Link: https://lkml.kernel.org/r/20200921175539.GB387368@google.com
[akpm@linux-foundation.org: pidfd_get_pid() gained an argument]
[sfr@canb.auug.org.au: fix up for "iov_iter: transparently handle compat iovecs in import_iovec"]
  Link: https://lkml.kernel.org/r/20200928212542.468e1fef@canb.auug.org.au

Signed-off-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Cc: Brian Geffon <bgeffon@google.com>
Cc: Christian Brauner <christian@brauner.io>
Cc: Daniel Colascione <dancol@google.com>
Cc: Jann Horn <jannh@google.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: John Dias <joaodias@google.com>
Cc: Kirill Tkhai <ktkhai@virtuozzo.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Oleksandr Natalenko <oleksandr@redhat.com>
Cc: Sandeep Patil <sspatil@google.com>
Cc: SeongJae Park <sj38.park@gmail.com>
Cc: SeongJae Park <sjpark@amazon.de>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Sonny Rao <sonnyrao@google.com>
Cc: Tim Murray <timmurray@google.com>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Florian Weimer <fw@deneb.enyo.de>
Cc: <linux-man@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200302193630.68771-3-minchan@kernel.org
Link: http://lkml.kernel.org/r/20200508183320.GA125527@google.com
Link: http://lkml.kernel.org/r/20200622192900.22757-4-minchan@kernel.org
Link: https://lkml.kernel.org/r/20200901000633.1920247-4-minchan@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-18 09:27:10 -07:00
Minchan Kim 1aa92cd31c pid: move pidfd_get_pid() to pid.c
process_madvise syscall needs pidfd_get_pid function to translate pidfd to
pid so this patch move the function to kernel/pid.c.

Suggested-by: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Signed-off-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Reviewed-by: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jann Horn <jannh@google.com>
Cc: Brian Geffon <bgeffon@google.com>
Cc: Daniel Colascione <dancol@google.com>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: John Dias <joaodias@google.com>
Cc: Kirill Tkhai <ktkhai@virtuozzo.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Oleksandr Natalenko <oleksandr@redhat.com>
Cc: Sandeep Patil <sspatil@google.com>
Cc: SeongJae Park <sj38.park@gmail.com>
Cc: SeongJae Park <sjpark@amazon.de>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Sonny Rao <sonnyrao@google.com>
Cc: Tim Murray <timmurray@google.com>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Florian Weimer <fw@deneb.enyo.de>
Cc: <linux-man@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200302193630.68771-5-minchan@kernel.org
Link: http://lkml.kernel.org/r/20200622192900.22757-3-minchan@kernel.org
Link: https://lkml.kernel.org/r/20200901000633.1920247-3-minchan@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-18 09:27:10 -07:00
Jens Axboe 91989c7078 task_work: cleanup notification modes
A previous commit changed the notification mode from true/false to an
int, allowing notify-no, notify-yes, or signal-notify. This was
backwards compatible in the sense that any existing true/false user
would translate to either 0 (on notification sent) or 1, the latter
which mapped to TWA_RESUME. TWA_SIGNAL was assigned a value of 2.

Clean this up properly, and define a proper enum for the notification
mode. Now we have:

- TWA_NONE. This is 0, same as before the original change, meaning no
  notification requested.
- TWA_RESUME. This is 1, same as before the original change, meaning
  that we use TIF_NOTIFY_RESUME.
- TWA_SIGNAL. This uses TIF_SIGPENDING/JOBCTL_TASK_WORK for the
  notification.

Clean up all the callers, switching their 0/1/false/true to using the
appropriate TWA_* mode for notifications.

Fixes: e91b481623 ("task_work: teach task_work_add() to do signal_wake_up()")
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-10-17 15:05:30 -06:00