linux-stable.git/kernel/power, branch linux-5.6.y

PM: hibernate: Freeze kernel threads in software_resume()

2020-05-06T06:16:38+00:00

commit 2351f8d295ed63393190e39c2f7c1fee1a80578f upstream.

Currently the kernel threads are not frozen in software_resume(), so
between dpm_suspend_start(PMSG_QUIESCE) and resume_target_kernel(),
system_freezable_power_efficient_wq can still try to submit SCSI
commands and this can cause a panic since the low level SCSI driver
(e.g. hv_storvsc) has quiesced the SCSI adapter and can not accept
any SCSI commands: https://lkml.org/lkml/2020/4/10/47

At first I posted a fix (https://lkml.org/lkml/2020/4/21/1318) trying
to resolve the issue from hv_storvsc, but with the help of
Bart Van Assche, I realized it's better to fix software_resume(),
since this looks like a generic issue, not only pertaining to SCSI.

Cc: All applicable 
Signed-off-by: Dexuan Cui 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman

PM / hibernate: fix typo "reserverd_size" -> "reserved_size"

2020-02-20T10:58:01+00:00

Fix a mistake in a variable name in a comment.

Signed-off-by: Alexandre Belloni 
Signed-off-by: Rafael J. Wysocki

ACPI: PM: s2idle: Avoid possible race related to the EC GPE

2020-02-11T09:11:02+00:00

It is theoretically possible for the ACPI EC GPE to be set after the
s2idle_ops->wake() called from s2idle_loop() has returned and before
the subsequent pm_wakeup_pending() check is carried out.  If that
happens, the resulting wakeup event will cause the system to resume
even though it may be a spurious one.

To avoid that race, first make the ->wake() callback in struct
platform_s2idle_ops return a bool value indicating whether or not
to let the system resume and rearrange s2idle_loop() to use that
value instad of the direct pm_wakeup_pending() call if ->wake() is
present.

Next, rework acpi_s2idle_wake() to process EC events and check
pm_wakeup_pending() before re-arming the SCI for system wakeup
to prevent it from triggering prematurely and add comments to
that function to explain the rationale for the new code flow.

Fixes: 56b991849009 ("PM: sleep: Simplify suspend-to-idle control flow")
Cc: 5.4+  # 5.4+
Signed-off-by: Rafael J. Wysocki

Merge back new material related to system-wide PM for v5.6.

2020-01-23T15:00:56+00:00

PM: hibernate: fix crashes with init_on_free=1

2020-01-16T22:51:45+00:00

Upon resuming from hibernation, free pages may contain stale data from
the kernel that initiated the resume. This breaks the invariant
inflicted by init_on_free=1 that freed pages must be zeroed.

To deal with this problem, make clear_free_pages() also clear the free
pages when init_on_free is enabled.

Fixes: 6471384af2a6 ("mm: security: introduce init_on_alloc=1 and init_on_free=1 boot options")
Reported-by: Johannes Stezenbach 
Signed-off-by: Alexander Potapenko 
Cc: 5.3+  # 5.3+
Signed-off-by: Rafael J. Wysocki

PM: suspend: Add sysfs attribute to control the "sync on suspend" behavior

2020-01-16T20:47:03+00:00

The sysfs attribute `/sys/power/sync_on_suspend` controls, whether or not
filesystems are synced by the kernel before system suspend.

Congruously, the behaviour of build-time switch CONFIG_SUSPEND_SKIP_SYNC
is slightly changed: It now defines the run-tim default for the new sysfs
attribute `/sys/power/sync_on_suspend`.

The run-time attribute is added because the existing corresponding
build-time Kconfig flag for (`CONFIG_SUSPEND_SKIP_SYNC`) is not flexible
enough. E.g. Linux distributions that provide pre-compiled kernels
usually want to stick with the default (sync filesystems before suspend)
but under special conditions this needs to be changed.

One example for such a special condition is user-space handling of
suspending block devices (e.g. using `cryptsetup luksSuspend` or `dmsetup
suspend`) before system suspend. The Kernel trying to sync filesystems
after the underlying block device already got suspended obviously leads
to dead-locks. Be aware that you have to take care of the filesystem sync
yourself before suspending the system in those scenarios.

Signed-off-by: Jonas Meurer 
Signed-off-by: Rafael J. Wysocki

PM: hibernate: fix spelling mistake "shapshot" -> "snapshot"

2020-01-10T11:15:30+00:00

There is a spelling mistake in a pr_info message. Fix it.

Signed-off-by: Colin Ian King 
Signed-off-by: Rafael J. Wysocki

PM: hibernate: Add more logging on hibernation failure

2020-01-07T12:31:12+00:00

Hibernation fails when the kernel cannot allocate enough memory
to copy all pages of RAM in use.

Ensure that the failure reason is clearly logged, and clearly
attributable to the hibernation module.

Signed-off-by: Luigi Semenzato 
[ rjw: Subject & changelog ]
Signed-off-by: Rafael J. Wysocki

PM: hibernate: improve arithmetic division in preallocate_highmem_fraction()

2020-01-07T11:42:56+00:00

do_div() does a 64-by-32 division. Use div64_u64() instead of
do_div() if the divisor is u64, to avoid truncation to 32-bit.

This change also cleans up code a tad.

Signed-off-by: Wen Yang 
[ rjw: Subject ]
Signed-off-by: Rafael J. Wysocki

PM: sleep: Switch to rtc_time64_to_tm()/rtc_tm_to_time64()

2019-12-20T08:58:08+00:00

Call the 64bit versions of rtc_tm time conversion to avoid the y2038 issue.

Signed-off-by: Alexandre Belloni 
Signed-off-by: Rafael J. Wysocki