Commit Graph

1208 Commits

Author SHA1 Message Date
Anna-Maria Behnsen
bccc8d1550 PM: s2idle: Make sure CPUs will wakeup directly on resume
commit 3c89a068bf upstream.

s2idle works like a regular suspend with freezing processes and freezing
devices. All CPUs except the control CPU go into idle. Once this is
completed the control CPU kicks all other CPUs out of idle, so that they
reenter the idle loop and then enter s2idle state. The control CPU then
issues an swait() on the suspend state and therefore enters the idle loop
as well.

Due to being kicked out of idle, the other CPUs leave their NOHZ states,
which means the tick is active and the corresponding hrtimer is programmed
to the next jiffie.

On entering s2idle the CPUs shut down their local clockevent device to
prevent wakeups. The last CPU which enters s2idle shuts down its local
clockevent and freezes timekeeping.

On resume, one of the CPUs receives the wakeup interrupt, unfreezes
timekeeping and its local clockevent and starts the resume process. At that
point all other CPUs are still in s2idle with their clockevents switched
off. They only resume when they are kicked by another CPU or after resuming
devices and then receiving a device interrupt.

That means there is no guarantee that all CPUs will wakeup directly on
resume. As a consequence there is no guarantee that timers which are queued
on those CPUs and should expire directly after resume, are handled. Also
timer list timers which are remotely queued to one of those CPUs after
resume will not result in a reprogramming IPI as the tick is
active. Queueing a hrtimer will also not result in a reprogramming IPI
because the first hrtimer event is already in the past.

The recent introduction of the timer pull model (7ee9887703 ("timers:
Implement the hierarchical pull model")) amplifies this problem, if the
current migrator is one of the non woken up CPUs. When a non pinned timer
list timer is queued and the queuing CPU goes idle, it relies on the still
suspended migrator CPU to expire the timer which will happen by chance.

The problem exists since commit 8d89835b04 ("PM: suspend: Do not pause
cpuidle in the suspend-to-idle path"). There the cpuidle_pause() call which
in turn invoked a wakeup for all idle CPUs was moved to a later point in
the resume process. This might not be reached or reached very late because
it waits on a timer of a still suspended CPU.

Address this by kicking all CPUs out of idle after the control CPU returns
from swait() so that they resume their timers and restore consistent system
state.

Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218641
Fixes: 8d89835b04 ("PM: suspend: Do not pause cpuidle in the suspend-to-idle path")
Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Mario Limonciello <mario.limonciello@amd.com>
Cc: 5.16+ <stable@kernel.org> # 5.16+
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-17 11:18:22 +02:00
Maulik Shah
a7b6523f92 PM: suspend: Set mem_sleep_current during kernel command line setup
[ Upstream commit 9bc4ffd32e ]

psci_init_system_suspend() invokes suspend_set_ops() very early during
bootup even before kernel command line for mem_sleep_default is setup.
This leads to kernel command line mem_sleep_default=s2idle not working
as mem_sleep_current gets changed to deep via suspend_set_ops() and never
changes back to s2idle.

Set mem_sleep_current along with mem_sleep_default during kernel command
line setup as default suspend mode.

Fixes: faf7ec4a92 ("drivers: firmware: psci: add system suspend support")
CC: stable@vger.kernel.org # 5.4+
Signed-off-by: Maulik Shah <quic_mkshah@quicinc.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-04-03 15:19:28 +02:00
Hongchen Zhang
3a081586c7 PM: hibernate: Enforce ordering during image compression/decompression
commit 71cd7e80cf upstream.

An S4 (suspend to disk) test on the LoongArch 3A6000 platform sometimes
fails with the following error messaged in the dmesg log:

	Invalid LZO compressed length

That happens because when compressing/decompressing the image, the
synchronization between the control thread and the compress/decompress/crc
thread is based on a relaxed ordering interface, which is unreliable, and the
following situation may occur:

CPU 0					CPU 1
save_image_lzo				lzo_compress_threadfn
					  atomic_set(&d->stop, 1);
  atomic_read(&data[thr].stop)
  data[thr].cmp = data[thr].cmp_len;
	  				  WRITE data[thr].cmp_len

Then CPU0 gets a stale cmp_len and writes it to disk. During resume from S4,
wrong cmp_len is loaded.

To maintain data consistency between the two threads, use the acquire/release
variants of atomic set and read operations.

Fixes: 081a9d043c ("PM / Hibernate: Improve performance of LZO/plain hibernation, checksum image")
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Hongchen Zhang <zhanghongchen@loongson.cn>
Co-developed-by: Weihao Li <liweihao@loongson.cn>
Signed-off-by: Weihao Li <liweihao@loongson.cn>
[ rjw: Subject rewrite and changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-31 16:16:58 -08:00
Brian Geffon
d150294818 PM: hibernate: Clean up sync_read handling in snapshot_write_next()
commit d08970df19 upstream.

In snapshot_write_next(), sync_read is set and unset in three different
spots unnecessiarly. As a result there is a subtle bug where the first
page after the meta data has been loaded unconditionally sets sync_read
to 0. If this first PFN was actually a highmem page, then the returned
buffer will be the global "buffer," and the page needs to be loaded
synchronously.

That is, I'm not sure we can always assume the following to be safe:

	handle->buffer = get_buffer(&orig_bm, &ca);
	handle->sync_read = 0;

Because get_buffer() can call get_highmem_page_buffer() which can
return 'buffer'.

The easiest way to address this is just set sync_read before
snapshot_write_next() returns if handle->buffer == buffer.

Signed-off-by: Brian Geffon <bgeffon@google.com>
Fixes: 8357376d3d ("[PATCH] swsusp: Improve handling of highmem")
Cc: All applicable <stable@vger.kernel.org>
[ rjw: Subject and changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28 17:07:11 +00:00
Brian Geffon
567c6f6495 PM: hibernate: Use __get_safe_page() rather than touching the list
commit f0c7183008 upstream.

We found at least one situation where the safe pages list was empty and
get_buffer() would gladly try to use a NULL pointer.

Signed-off-by: Brian Geffon <bgeffon@google.com>
Fixes: 8357376d3d ("[PATCH] swsusp: Improve handling of highmem")
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28 17:07:11 +00:00
Chungkai Yang
9a2c57fd32 PM: QoS: Restore support for default value on frequency QoS
commit 3a8395b565 upstream.

Commit 8d36694245 ("PM: QoS: Add check to make sure CPU freq is
non-negative") makes sure CPU freq is non-negative to avoid negative
value converting to unsigned data type. However, when the value is
PM_QOS_DEFAULT_VALUE, pm_qos_update_target specifically uses
c->default_value which is set to FREQ_QOS_MIN/MAX_DEFAULT_VALUE when
cpufreq_policy_alloc is executed, for this case handling.

Adding check for PM_QOS_DEFAULT_VALUE to let default setting work will
fix this problem.

Fixes: 8d36694245 ("PM: QoS: Add check to make sure CPU freq is non-negative")
Link: https://lore.kernel.org/lkml/20230626035144.19717-1-Chung-kai.Yang@mediatek.com/
Link: https://lore.kernel.org/lkml/20230627071727.16646-1-Chung-kai.Yang@mediatek.com/
Link: https://lore.kernel.org/lkml/CAJZ5v0gxNOWhC58PHeUhW_tgf6d1fGJVZ1x91zkDdht11yUv-A@mail.gmail.com/
Signed-off-by: Chungkai Yang <Chung-kai.Yang@mediatek.com>
Cc: 6.0+ <stable@vger.kernel.org> # 6.0+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-23 13:49:45 +02:00
Chen Yu
72f3217aa1 PM: hibernate: Do not get block device exclusively in test_resume mode
[ Upstream commit 5904de0d73 ]

The system refused to do a test_resume because it found that the
swap device has already been taken by someone else. Specifically,
the swsusp_check()->blkdev_get_by_dev(FMODE_EXCL) is supposed to
do this check.

Steps to reproduce:
 dd if=/dev/zero of=/swapfile bs=$(cat /proc/meminfo |
       awk '/MemTotal/ {print $2}') count=1024 conv=notrunc
 mkswap /swapfile
 swapon /swapfile
 swap-offset /swapfile
 echo 34816 > /sys/power/resume_offset
 echo test_resume > /sys/power/disk
 echo disk > /sys/power/state

 PM: Using 3 thread(s) for compression
 PM: Compressing and saving image data (293150 pages)...
 PM: Image saving progress:   0%
 PM: Image saving progress:  10%
 ata1: SATA link up 1.5 Gbps (SStatus 113 SControl 300)
 ata1.00: configured for UDMA/100
 ata2: SATA link down (SStatus 0 SControl 300)
 ata5: SATA link down (SStatus 0 SControl 300)
 ata6: SATA link down (SStatus 0 SControl 300)
 ata3: SATA link down (SStatus 0 SControl 300)
 ata4: SATA link down (SStatus 0 SControl 300)
 PM: Image saving progress:  20%
 PM: Image saving progress:  30%
 PM: Image saving progress:  40%
 PM: Image saving progress:  50%
 pcieport 0000:00:02.5: pciehp: Slot(0-5): No device found
 PM: Image saving progress:  60%
 PM: Image saving progress:  70%
 PM: Image saving progress:  80%
 PM: Image saving progress:  90%
 PM: Image saving done
 PM: hibernation: Wrote 1172600 kbytes in 2.70 seconds (434.29 MB/s)
 PM: S|
 PM: hibernation: Basic memory bitmaps freed
 PM: Image not found (code -16)

This is because when using the swapfile as the hibernation storage,
the block device where the swapfile is located has already been mounted
by the OS distribution(usually mounted as the rootfs). This is not
an issue for normal hibernation, because software_resume()->swsusp_check()
happens before the block device(rootfs) mount. But it is a problem for the
test_resume mode. Because when test_resume happens, the block device has
been mounted already.

Thus remove the FMODE_EXCL for test_resume mode. This would not be a
problem because in test_resume stage, the processes have already been
frozen, and the race condition described in
Commit 39fbef4b0f ("PM: hibernate: Get block device exclusively in swsusp_check()")
is unlikely to happen.

Fixes: 39fbef4b0f ("PM: hibernate: Get block device exclusively in swsusp_check()")
Reported-by: Yifan Li <yifan2.li@intel.com>
Suggested-by: Pavankumar Kondeti <quic_pkondeti@quicinc.com>
Tested-by: Pavankumar Kondeti <quic_pkondeti@quicinc.com>
Tested-by: Wendy Wang <wendy.wang@intel.com>
Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-11 23:03:38 +09:00
Chen Yu
208ba216cc PM: hibernate: Turn snapshot_test into global variable
[ Upstream commit 08169a162f ]

There is need to check snapshot_test and open block device
in different mode, so as to avoid the race condition.

No functional changes intended.

Suggested-by: Pavankumar Kondeti <quic_pkondeti@quicinc.com>
Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Stable-dep-of: 5904de0d73 ("PM: hibernate: Do not get block device exclusively in test_resume mode")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-11 23:03:38 +09:00
Greg Kroah-Hartman
5100c4efc3 PM: EM: fix memory leak with using debugfs_lookup()
[ Upstream commit a0e8c13ccd ]

When calling debugfs_lookup() the result must have dput() called on it,
otherwise the memory will leak over time.  To make things simpler, just
call debugfs_lookup_and_remove() instead which handles all of the logic
at once.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-03-10 09:33:53 +01:00
Rafael J. Wysocki
f2173508b1 PM: sleep: Avoid using pr_cont() in the tasks freezing code
commit a449dfbfc0 upstream.

Using pr_cont() in the tasks freezing code related to system-wide
suspend and hibernation is problematic, because the continuation
messages printed there are susceptible to interspersing with other
unrelated messages which results in output that is hard to
understand.

Address this issue by modifying try_to_freeze_tasks() to print
messages that don't require continuations and adjusting its
callers accordingly.

Reported-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Cc: Paul Menzel <pmenzel@molgen.mpg.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-03 11:52:23 +01:00
xiongxin
574b10475d PM: hibernate: Fix mistake in kerneldoc comment
[ Upstream commit 6e5d7300cb ]

The actual maximum image size formula in hibernate_preallocate_memory()
is as follows:

max_size = (count - (size + PAGES_FOR_IO)) / 2
	    - 2 * DIV_ROUND_UP(reserved_size, PAGE_SIZE);

but the one in the kerneldoc comment of the function is different and
incorrect.

Fixes: ddeb648708 ("PM / Hibernate: Add sysfs knob to control size of memory for drivers")
Signed-off-by: xiongxin <xiongxin@kylinos.cn>
[ rjw: Subject and changelog rewrite ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-31 13:31:55 +01:00
Mario Limonciello
85850af4fc PM: hibernate: Allow hybrid sleep to work with s2idle
Hybrid sleep is currently hardcoded to only operate with S3 even
on systems that might not support it.

Instead of assuming this mode is what the user wants to use, for
hybrid sleep follow the setting of `mem_sleep_current` which
will respect mem_sleep_default kernel command line and policy
decisions made by the presence of the FADT low power idle bit.

Fixes: 81d45bdf89 ("PM / hibernate: Untangle power_down()")
Reported-and-tested-by: kolAflash <kolAflash@kolahilft.de>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=216574
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-10-25 14:53:19 +02:00
Linus Torvalds
30c999937f Scheduler changes for v6.1:
- Debuggability:
 
      - Change most occurances of BUG_ON() to WARN_ON_ONCE()
 
      - Reorganize & fix TASK_ state comparisons, turn it into a bitmap
 
      - Update/fix misc scheduler debugging facilities
 
  - Load-balancing & regular scheduling:
 
      - Improve the behavior of the scheduler in presence of lot of
        SCHED_IDLE tasks - in particular they should not impact other
        scheduling classes.
 
      - Optimize task load tracking, cleanups & fixes
 
      - Clean up & simplify misc load-balancing code
 
  - Freezer:
 
      - Rewrite the core freezer to behave better wrt thawing and be simpler
        in general, by replacing PF_FROZEN with TASK_FROZEN & fixing/adjusting
        all the fallout.
 
  - Deadline scheduler:
 
      - Fix the DL capacity-aware code
 
      - Factor out dl_task_is_earliest_deadline() & replenish_dl_new_period()
 
      - Relax/optimize locking in task_non_contending()
 
  - Cleanups:
 
      - Factor out the update_current_exec_runtime() helper
 
      - Various cleanups, simplifications
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'sched-core-2022-10-07' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull scheduler updates from Ingo Molnar:
 "Debuggability:

   - Change most occurances of BUG_ON() to WARN_ON_ONCE()

   - Reorganize & fix TASK_ state comparisons, turn it into a bitmap

   - Update/fix misc scheduler debugging facilities

  Load-balancing & regular scheduling:

   - Improve the behavior of the scheduler in presence of lot of
     SCHED_IDLE tasks - in particular they should not impact other
     scheduling classes.

   - Optimize task load tracking, cleanups & fixes

   - Clean up & simplify misc load-balancing code

  Freezer:

   - Rewrite the core freezer to behave better wrt thawing and be
     simpler in general, by replacing PF_FROZEN with TASK_FROZEN &
     fixing/adjusting all the fallout.

  Deadline scheduler:

   - Fix the DL capacity-aware code

   - Factor out dl_task_is_earliest_deadline() &
     replenish_dl_new_period()

   - Relax/optimize locking in task_non_contending()

  Cleanups:

   - Factor out the update_current_exec_runtime() helper

   - Various cleanups, simplifications"

* tag 'sched-core-2022-10-07' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (41 commits)
  sched: Fix more TASK_state comparisons
  sched: Fix TASK_state comparisons
  sched/fair: Move call to list_last_entry() in detach_tasks
  sched/fair: Cleanup loop_max and loop_break
  sched/fair: Make sure to try to detach at least one movable task
  sched: Show PF_flag holes
  freezer,sched: Rewrite core freezer logic
  sched: Widen TAKS_state literals
  sched/wait: Add wait_event_state()
  sched/completion: Add wait_for_completion_state()
  sched: Add TASK_ANY for wait_task_inactive()
  sched: Change wait_task_inactive()s match_state
  freezer,umh: Clean up freezer/initrd interaction
  freezer: Have {,un}lock_system_sleep() save/restore flags
  sched: Rename task_running() to task_on_cpu()
  sched/fair: Cleanup for SIS_PROP
  sched/fair: Default to false in test_idle_cores()
  sched/fair: Remove useless check in select_idle_core()
  sched/fair: Avoid double search on same cpu
  sched/fair: Remove redundant check in select_idle_smt()
  ...
2022-10-10 09:10:28 -07:00
Mario Limonciello
811d59fdf5 ACPI: s2idle: Add a new ->check() callback for platform_s2idle_ops
On some platforms it is found that Linux more aggressively enters s2idle
than Windows enters Modern Standby and this uncovers some synchronization
issues for the platform.  To aid in debugging this class of problems in
the future, add support for an extra optional callback intended for
drivers to emit extra debugging.

Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lore.kernel.org/r/20220829162953.5947-2-mario.limonciello@amd.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2022-09-09 17:37:40 +02:00
Peter Zijlstra
f5d39b0208 freezer,sched: Rewrite core freezer logic
Rewrite the core freezer to behave better wrt thawing and be simpler
in general.

By replacing PF_FROZEN with TASK_FROZEN, a special block state, it is
ensured frozen tasks stay frozen until thawed and don't randomly wake
up early, as is currently possible.

As such, it does away with PF_FROZEN and PF_FREEZER_SKIP, freeing up
two PF_flags (yay!).

Specifically; the current scheme works a little like:

	freezer_do_not_count();
	schedule();
	freezer_count();

And either the task is blocked, or it lands in try_to_freezer()
through freezer_count(). Now, when it is blocked, the freezer
considers it frozen and continues.

However, on thawing, once pm_freezing is cleared, freezer_count()
stops working, and any random/spurious wakeup will let a task run
before its time.

That is, thawing tries to thaw things in explicit order; kernel
threads and workqueues before doing bringing SMP back before userspace
etc.. However due to the above mentioned races it is entirely possible
for userspace tasks to thaw (by accident) before SMP is back.

This can be a fatal problem in asymmetric ISA architectures (eg ARMv9)
where the userspace task requires a special CPU to run.

As said; replace this with a special task state TASK_FROZEN and add
the following state transitions:

	TASK_FREEZABLE	-> TASK_FROZEN
	__TASK_STOPPED	-> TASK_FROZEN
	__TASK_TRACED	-> TASK_FROZEN

The new TASK_FREEZABLE can be set on any state part of TASK_NORMAL
(IOW. TASK_INTERRUPTIBLE and TASK_UNINTERRUPTIBLE) -- any such state
is already required to deal with spurious wakeups and the freezer
causes one such when thawing the task (since the original state is
lost).

The special __TASK_{STOPPED,TRACED} states *can* be restored since
their canonical state is in ->jobctl.

With this, frozen tasks need an explicit TASK_FROZEN wakeup and are
free of undue (early / spurious) wakeups.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lore.kernel.org/r/20220822114649.055452969@infradead.org
2022-09-07 21:53:50 +02:00
Peter Zijlstra
5950e5d574 freezer: Have {,un}lock_system_sleep() save/restore flags
Rafael explained that the reason for having both PF_NOFREEZE and
PF_FREEZER_SKIP is that {,un}lock_system_sleep() is callable from
kthread context that has previously called set_freezable().

In preparation of merging the flags, have {,un}lock_system_slee() save
and restore current->flags.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lore.kernel.org/r/20220822114648.725003428@infradead.org
2022-09-07 21:53:48 +02:00
Linus Torvalds
228dfe98a3 Char / Misc driver changes for 6.0-rc1
Here is the large set of char and misc and other driver subsystem
 changes for 6.0-rc1.
 
 Highlights include:
 	- large set of IIO driver updates, additions, and cleanups
 	- new habanalabs device support added (loads of register maps
 	  much like GPUs have)
 	- soundwire driver updates
 	- phy driver updates
 	- slimbus driver updates
 	- tiny virt driver fixes and updates
 	- misc driver fixes and updates
 	- interconnect driver updates
 	- hwtracing driver updates
 	- fpga driver updates
 	- extcon driver updates
 	- firmware driver updates
 	- counter driver update
 	- mhi driver fixes and updates
 	- binder driver fixes and updates
 	- speakup driver fixes
 
 Full details are in the long shortlog contents.
 
 All of these have been in linux-next for a while without any reported
 problems.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-6.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull char / misc driver updates from Greg KH:
 "Here is the large set of char and misc and other driver subsystem
  changes for 6.0-rc1.

  Highlights include:

   - large set of IIO driver updates, additions, and cleanups

   - new habanalabs device support added (loads of register maps much
     like GPUs have)

   - soundwire driver updates

   - phy driver updates

   - slimbus driver updates

   - tiny virt driver fixes and updates

   - misc driver fixes and updates

   - interconnect driver updates

   - hwtracing driver updates

   - fpga driver updates

   - extcon driver updates

   - firmware driver updates

   - counter driver update

   - mhi driver fixes and updates

   - binder driver fixes and updates

   - speakup driver fixes

  All of these have been in linux-next for a while without any reported
  problems"

* tag 'char-misc-6.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (634 commits)
  drivers: lkdtm: fix clang -Wformat warning
  char: remove VR41XX related char driver
  misc: Mark MICROCODE_MINOR unused
  spmi: trace: fix stack-out-of-bound access in SPMI tracing functions
  dt-bindings: iio: adc: Add compatible for MT8188
  iio: light: isl29028: Fix the warning in isl29028_remove()
  iio: accel: sca3300: Extend the trigger buffer from 16 to 32 bytes
  iio: fix iio_format_avail_range() printing for none IIO_VAL_INT
  iio: adc: max1027: unlock on error path in max1027_read_single_value()
  iio: proximity: sx9324: add empty line in front of bullet list
  iio: magnetometer: hmc5843: Remove duplicate 'the'
  iio: magn: yas530: Use DEFINE_RUNTIME_DEV_PM_OPS() and pm_ptr() macros
  iio: magnetometer: ak8974: Use DEFINE_RUNTIME_DEV_PM_OPS() and pm_ptr() macros
  iio: light: veml6030: Use DEFINE_RUNTIME_DEV_PM_OPS() and pm_ptr() macros
  iio: light: vcnl4035: Use DEFINE_RUNTIME_DEV_PM_OPS() and pm_ptr() macros
  iio: light: vcnl4000: Use DEFINE_RUNTIME_DEV_PM_OPS() and pm_ptr() macros
  iio: light: tsl2591: Use DEFINE_RUNTIME_DEV_PM_OPS() and pm_ptr()
  iio: light: tsl2583: Use DEFINE_RUNTIME_DEV_PM_OPS and pm_ptr()
  iio: light: isl29028: Use DEFINE_RUNTIME_DEV_PM_OPS() and pm_ptr()
  iio: light: gp2ap002: Switch to DEFINE_RUNTIME_DEV_PM_OPS and pm_ptr()
  ...
2022-08-04 11:05:48 -07:00
Linus Torvalds
c013d0af81 for-5.20/block-2022-07-29
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Merge tag 'for-5.20/block-2022-07-29' of git://git.kernel.dk/linux-block

Pull block updates from Jens Axboe:

 - Improve the type checking of request flags (Bart)

 - Ensure queue mapping for a single queues always picks the right queue
   (Bart)

 - Sanitize the io priority handling (Jan)

 - rq-qos race fix (Jinke)

 - Reserved tags handling improvements (John)

 - Separate memory alignment from file/disk offset aligment for O_DIRECT
   (Keith)

 - Add new ublk driver, userspace block driver using io_uring for
   communication with the userspace backend (Ming)

 - Use try_cmpxchg() to cleanup the code in various spots (Uros)

 - Finally remove bdevname() (Christoph)

 - Clean up the zoned device handling (Christoph)

 - Clean up independent access range support (Christoph)

 - Clean up and improve block sysfs handling (Christoph)

 - Clean up and improve teardown of block devices.

   This turns the usual two step process into something that is simpler
   to implement and handle in block drivers (Christoph)

 - Clean up chunk size handling (Christoph)

 - Misc cleanups and fixes (Bart, Bo, Dan, GuoYong, Jason, Keith, Liu,
   Ming, Sebastian, Yang, Ying)

* tag 'for-5.20/block-2022-07-29' of git://git.kernel.dk/linux-block: (178 commits)
  ublk_drv: fix double shift bug
  ublk_drv: make sure that correct flags(features) returned to userspace
  ublk_drv: fix error handling of ublk_add_dev
  ublk_drv: fix lockdep warning
  block: remove __blk_get_queue
  block: call blk_mq_exit_queue from disk_release for never added disks
  blk-mq: fix error handling in __blk_mq_alloc_disk
  ublk: defer disk allocation
  ublk: rewrite ublk_ctrl_get_queue_affinity to not rely on hctx->cpumask
  ublk: fold __ublk_create_dev into ublk_ctrl_add_dev
  ublk: cleanup ublk_ctrl_uring_cmd
  ublk: simplify ublk_ch_open and ublk_ch_release
  ublk: remove the empty open and release block device operations
  ublk: remove UBLK_IO_F_PREFLUSH
  ublk: add a MAINTAINERS entry
  block: don't allow the same type rq_qos add more than once
  mmc: fix disk/queue leak in case of adding disk failure
  ublk_drv: fix an IS_ERR() vs NULL check
  ublk: remove UBLK_IO_F_INTEGRITY
  ublk_drv: remove unneeded semicolon
  ...
2022-08-02 13:46:35 -07:00
Rafael J. Wysocki
aa727b7b4b Merge branches 'pm-devfreq', 'pm-qos', 'pm-tools' and 'pm-docs'
Merge devfreq changes, PM QoS change, and power management tools and
documentation changes for v5.20-rc1:

 - Add new devfreq driver for Mediatek CCI (Cache Coherent
   Interconnect) (Johnson Wang).

 - Convert the Samsung Exynos SoC Bus bindings to DT schema of
   exynos-bus.c (Krzysztof Kozlowski).

 - Address kernel-doc warnings by adding the description for unused
   fucntion parameters in devfreq core (Mauro Carvalho Chehab).

 - Use NULL to pass a null pointer rather than zero according to the
   function propotype in imx-bus.c (Colin Ian King).

 - Print error message instead of error interger value in
   tegra30-devfreq.c (Dmitry Osipenko).

 - Add checks to prevent setting negative frequency QoS limits for
   CPUs (Shivnandan Kumar).

 - Update the pm-graph suite of utilities to the latest revision 5.9
   including multiple improvements (Todd Brandt).

 - Drop pme_interrupt reference from the PCI power management
   documentation (Mario Limonciello).

* pm-devfreq:
  PM / devfreq: tegra30: Add error message for devm_devfreq_add_device()
  PM / devfreq: imx-bus: use NULL to pass a null pointer rather than zero
  PM / devfreq: shut up kernel-doc warnings
  dt-bindings: interconnect: samsung,exynos-bus: convert to dtschema
  PM / devfreq: mediatek: Introduce MediaTek CCI devfreq driver
  dt-bindings: interconnect: Add MediaTek CCI dt-bindings

* pm-qos:
  PM: QoS: Add check to make sure CPU freq is non-negative

* pm-tools:
  pm-graph v5.9

* pm-docs:
  Documentation: PM: Drop pme_interrupt reference
2022-07-29 19:46:00 +02:00
Rafael J. Wysocki
954a83fc60 Merge branches 'pm-core', 'pm-sleep', 'powercap', 'pm-domains' and 'pm-em'
Merge core device power management changes for v5.20-rc1:

 - Extend support for wakeirq to callback wrappers used during system
   suspend and resume (Ulf Hansson).

 - Defer waiting for device probe before loading a hibernation image
   till the first actual device access to avoid possible deadlocks
   reported by syzbot (Tetsuo Handa).

 - Unify device_init_wakeup() for PM_SLEEP and !PM_SLEEP (Bjorn
   Helgaas).

 - Add Raptor Lake-P to the list of processors supported by the Intel
   RAPL driver (George D Sworo).

 - Add Alder Lake-N and Raptor Lake-P to the list of processors for
   which Power Limit4 is supported in the Intel RAPL driver (Sumeet
   Pawnikar).

 - Make pm_genpd_remove() check genpd_debugfs_dir against NULL before
   attempting to remove it (Hsin-Yi Wang).

 - Change the Energy Model code to represent power in micro-Watts and
   adjust its users accordingly (Lukasz Luba).

* pm-core:
  PM: runtime: Extend support for wakeirq for force_suspend|resume

* pm-sleep:
  PM: hibernate: defer device probing when resuming from hibernation
  PM: wakeup: Unify device_init_wakeup() for PM_SLEEP and !PM_SLEEP

* powercap:
  powercap: RAPL: Add Power Limit4 support for Alder Lake-N and Raptor Lake-P
  powercap: intel_rapl: Add support for RAPTORLAKE_P

* pm-domains:
  PM: domains: Ensure genpd_debugfs_dir exists before remove

* pm-em:
  cpufreq: scmi: Support the power scale in micro-Watts in SCMI v3.1
  firmware: arm_scmi: Get detailed power scale from perf
  Documentation: EM: Switch to micro-Watts scale
  PM: EM: convert power field to micro-Watts precision and align drivers
2022-07-29 19:33:13 +02:00
Shivnandan Kumar
8d36694245 PM: QoS: Add check to make sure CPU freq is non-negative
CPU frequency should never be negative.

If some client driver calls freq_qos_update_request with a
negative value which will be very high in absolute terms,
then frequency QoS sets max CPU freq at fmax as it considers
it's absolute value but it will add plist node with negative
priority.

plist node has priority from INT_MIN (highest) to INT_MAX(lowest).
Once priority is set as negative, another client will not be able
to reduce CPU frequency.

Adding check to make sure CPU freq is non-negative will fix
this problem.

Signed-off-by: Shivnandan Kumar <quic_kshivnan@quicinc.com>
[ rjw: Changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-07-26 20:48:33 +02:00
Tetsuo Handa
8386c414e2 PM: hibernate: defer device probing when resuming from hibernation
syzbot is reporting hung task at misc_open() [1], for there is a race
window of AB-BA deadlock which involves probe_count variable. Currently
wait_for_device_probe() from snapshot_open() from misc_open() can sleep
forever with misc_mtx held if probe_count cannot become 0.

When a device is probed by hub_event() work function, probe_count is
incremented before the probe function starts, and probe_count is
decremented after the probe function completed.

There are three cases that can prevent probe_count from dropping to 0.

  (a) A device being probed stopped responding (i.e. broken/malicious
      hardware).

  (b) A process emulating a USB device using /dev/raw-gadget interface
      stopped responding for some reason.

  (c) New device probe requests keeps coming in before existing device
      probe requests complete.

The phenomenon syzbot is reporting is (b). A process which is holding
system_transition_mutex and misc_mtx is waiting for probe_count to become
0 inside wait_for_device_probe(), but the probe function which is called
 from hub_event() work function is waiting for the processes which are
blocked at mutex_lock(&misc_mtx) to respond via /dev/raw-gadget interface.

This patch mitigates (b) by deferring wait_for_device_probe() from
snapshot_open() to snapshot_write() and snapshot_ioctl(). Please note that
the possibility of (b) remains as long as any thread which is emulating a
USB device via /dev/raw-gadget interface can be blocked by uninterruptible
blocking operations (e.g. mutex_lock()).

Please also note that (a) and (c) are not addressed. Regarding (c), we
should change the code to wait for only one device which contains the
image for resuming from hibernation. I don't know how to address (a), for
use of timeout for wait_for_device_probe() might result in loss of user
data in the image. Maybe we should require the userland to wait for the
image device before opening /dev/snapshot interface.

Link: https://syzkaller.appspot.com/bug?extid=358c9ab4c93da7b7238c [1]
Reported-by: syzbot <syzbot+358c9ab4c93da7b7238c@syzkaller.appspotmail.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Tested-by: syzbot <syzbot+358c9ab4c93da7b7238c@syzkaller.appspotmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-07-26 20:39:01 +02:00
Lukasz Luba
ae6ccaa650 PM: EM: convert power field to micro-Watts precision and align drivers
The milli-Watts precision causes rounding errors while calculating
efficiency cost for each OPP. This is especially visible in the 'simple'
Energy Model (EM), where the power for each OPP is provided from OPP
framework. This can cause some OPPs to be marked inefficient, while
using micro-Watts precision that might not happen.

Update all EM users which access 'power' field and assume the value is
in milli-Watts.

Solve also an issue with potential overflow in calculation of energy
estimation on 32bit machine. It's needed now since the power value
(thus the 'cost' as well) are higher.

Example calculation which shows the rounding error and impact:

power = 'dyn-power-coeff' * volt_mV * volt_mV * freq_MHz

power_a_uW = (100 * 600mW * 600mW * 500MHz) / 10^6 = 18000
power_a_mW = (100 * 600mW * 600mW * 500MHz) / 10^9 = 18

power_b_uW = (100 * 605mW * 605mW * 600MHz) / 10^6 = 21961
power_b_mW = (100 * 605mW * 605mW * 600MHz) / 10^9 = 21

max_freq = 2000MHz

cost_a_mW = 18 * 2000MHz/500MHz = 72
cost_a_uW = 18000 * 2000MHz/500MHz = 72000

cost_b_mW = 21 * 2000MHz/600MHz = 70 // <- artificially better
cost_b_uW = 21961 * 2000MHz/600MHz = 73203

The 'cost_b_mW' (which is based on old milli-Watts) is misleadingly
better that the 'cost_b_uW' (this patch uses micro-Watts) and such
would have impact on the 'inefficient OPPs' information in the Cpufreq
framework. This patch set removes the rounding issue.

Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-07-15 19:17:30 +02:00
Bart Van Assche
568e34ed73 PM: Use the enum req_op and blk_opf_t types
Improve static type checking by using the enum req_op type for variables
that represent a request operation and the new blk_opf_t type for
variables that represent request flags. Combine the first two
hib_submit_io() arguments into a single argument.

Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20220714180729.1065367-62-bvanassche@acm.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-14 12:14:33 -06:00
Kalesh Singh
261e224d6a pm/sleep: Add PM_USERSPACE_AUTOSLEEP Kconfig
Systems that initiate frequent suspend/resume from userspace
can make the kernel aware by enabling PM_USERSPACE_AUTOSLEEP
config.

This allows for certain sleep-sensitive code (wireguard/rng) to
decide on what preparatory work should be performed (or not) in
their pm_notification callbacks.

This patch was prompted by the discussion at [1] which attempts
to remove CONFIG_ANDROID that currently guards these code paths.

[1] https://lore.kernel.org/r/20220629150102.1582425-1-hch@lst.de/

Suggested-by: Jason A. Donenfeld <Jason@zx2c4.com>
Acked-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
Link: https://lore.kernel.org/r/20220630191230.235306-1-kaleshsingh@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-01 10:39:20 +02:00
Dmitry Osipenko
2027732600 PM: hibernate: Use kernel_can_power_off()
Use new kernel_can_power_off() API instead of legacy pm_power_off global
variable to fix regressed hibernation to disk where machine no longer
powers off when it should because ACPI power driver transitioned to the
new sys-off based API and it doesn't use pm_power_off anymore.

Fixes: 98f30d0ecf ("ACPI: power: Switch to sys-off handler API")
Tested-by: Ken Moffat <zarniwhoop@ntlworld.com>
Reported-by: Ken Moffat <zarniwhhop@ntlworld.com>
Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-06-21 20:57:30 +02:00
Linus Torvalds
9d004b2f4f cxl for 5.19
- Add driver-core infrastructure for lockdep validation of
   device_lock(), and fixup a deadlock report that was previously hidden
   behind the 'lockdep no validate' policy.
 
 - Add CXL _OSC support for claiming native control of CXL hotplug and
   error handling.
 
 - Disable suspend in the presence of CXL memory unless and until a
   protocol is identified for restoring PCI device context from memory
   hosted on CXL PCI devices.
 
 - Add support for snooping CXL mailbox commands to protect against
   inopportune changes, like set-partition with the 'immediate' flag set.
 
 - Rework how the driver detects legacy CXL 1.1 configurations (CXL DVSEC
   / 'mem_enable') before enabling new CXL 2.0 decode configurations (CXL
   HDM Capability).
 
 - Miscellaneous cleanups and fixes from -next exposure.
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Merge tag 'cxl-for-5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl

Pull cxl updates from Dan Williams:
 "Compute Express Link (CXL) updates for this cycle.

  The highlight is new driver-core infrastructure and CXL subsystem
  changes for allowing lockdep to validate device_lock() usage. Thanks
  to PeterZ for setting me straight on the current capabilities of the
  lockdep API, and Greg acked it as well.

  On the CXL ACPI side this update adds support for CXL _OSC so that
  platform firmware knows that it is safe to still grant Linux native
  control of PCIe hotplug and error handling in the presence of CXL
  devices. A circular dependency problem was discovered between suspend
  and CXL memory for cases where the suspend image might be stored in
  CXL memory where that image also contains the PCI register state to
  restore to re-enable the device. Disable suspend for now until an
  architecture is defined to clarify that conflict.

  Lastly a collection of reworks, fixes, and cleanups to the CXL
  subsystem where support for snooping mailbox commands and properly
  handling the "mem_enable" flow are the highlights.

  Summary:

   - Add driver-core infrastructure for lockdep validation of
     device_lock(), and fixup a deadlock report that was previously
     hidden behind the 'lockdep no validate' policy.

   - Add CXL _OSC support for claiming native control of CXL hotplug and
     error handling.

   - Disable suspend in the presence of CXL memory unless and until a
     protocol is identified for restoring PCI device context from memory
     hosted on CXL PCI devices.

   - Add support for snooping CXL mailbox commands to protect against
     inopportune changes, like set-partition with the 'immediate' flag
     set.

   - Rework how the driver detects legacy CXL 1.1 configurations (CXL
     DVSEC / 'mem_enable') before enabling new CXL 2.0 decode
     configurations (CXL HDM Capability).

   - Miscellaneous cleanups and fixes from -next exposure"

* tag 'cxl-for-5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl: (47 commits)
  cxl/port: Enable HDM Capability after validating DVSEC Ranges
  cxl/port: Reuse 'struct cxl_hdm' context for hdm init
  cxl/port: Move endpoint HDM Decoder Capability init to port driver
  cxl/pci: Drop @info argument to cxl_hdm_decode_init()
  cxl/mem: Merge cxl_dvsec_ranges() and cxl_hdm_decode_init()
  cxl/mem: Skip range enumeration if mem_enable clear
  cxl/mem: Consolidate CXL DVSEC Range enumeration in the core
  cxl/pci: Move cxl_await_media_ready() to the core
  cxl/mem: Validate port connectivity before dvsec ranges
  cxl/mem: Fix cxl_mem_probe() error exit
  cxl/pci: Drop wait_for_valid() from cxl_await_media_ready()
  cxl/pci: Consolidate wait_for_media() and wait_for_media_ready()
  cxl/mem: Drop mem_enabled check from wait_for_media()
  nvdimm: Fix firmware activation deadlock scenarios
  device-core: Kill the lockdep_mutex
  nvdimm: Drop nd_device_lock()
  ACPI: NFIT: Drop nfit_device_lock()
  nvdimm: Replace lockdep_mutex with local lock classes
  cxl: Drop cxl_device_lock()
  cxl/acpi: Add root device lockdep validation
  ...
2022-05-27 21:24:19 -07:00
Rafael J. Wysocki
16a23f394d Merge branches 'pm-em' and 'pm-cpuidle'
Marge Energy Model support updates and cpuidle updates for 5.19-rc1:

 - Update the Energy Model support code to allow the Energy Model to be
   artificial, which means that the power values may not be on a uniform
   scale with other devices providing power information, and update the
   cpufreq_cooling and devfreq_cooling thermal drivers to support
   artificial Energy Models (Lukasz Luba).

 - Make DTPM check the Energy Model type (Lukasz Luba).

 - Fix policy counter decrementation in cpufreq if Energy Model is in
   use (Pierre Gondois).

 - Add AlderLake processor support to the intel_idle driver (Zhang Rui).

 - Fix regression leading to no genpd governor in the PSCI cpuidle
   driver and fix the riscv-sbi cpuidle driver to allow a genpd
   governor to be used (Ulf Hansson).

* pm-em:
  PM: EM: Decrement policy counter
  powercap: DTPM: Check for Energy Model type
  thermal: cooling: Check Energy Model type in cpufreq_cooling and devfreq_cooling
  Documentation: EM: Add artificial EM registration description
  PM: EM: Remove old debugfs files and print all 'flags'
  PM: EM: Change the order of arguments in the .active_power() callback
  PM: EM: Use the new .get_cost() callback while registering EM
  PM: EM: Add artificial EM flag
  PM: EM: Add .get_cost() callback

* pm-cpuidle:
  cpuidle: riscv-sbi: Fix code to allow a genpd governor to be used
  cpuidle: psci: Fix regression leading to no genpd governor
  intel_idle: Add AlderLake support
2022-05-23 19:18:51 +02:00
Pierre Gondois
c9d8923bfb PM: EM: Decrement policy counter
In commit e458716a92 ("PM: EM: Mark inefficiencies in CPUFreq"),
cpufreq_cpu_get() is called without a cpufreq_cpu_put(), permanently
increasing the reference counts of the policy struct.

Decrement the reference count once the policy struct is not used
anymore.

Fixes: e458716a92 ("PM: EM: Mark inefficiencies in CPUFreq")
Tested-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Pierre Gondois <pierre.gondois@arm.com>
Reviewed-by: Vincent Donnefort <vincent.donnefort@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-05-11 19:15:14 +02:00
Dan Williams
9ea4dcf498 PM: CXL: Disable suspend
The CXL specification claims S3 support at a hardware level, but at a
system software level there are some missing pieces. Section 9.4 (CXL
2.0) rightly claims that "CXL mem adapters may need aux power to retain
memory context across S3", but there is no enumeration mechanism for the
OS to determine if a given adapter has that support. Moreover the save
state and resume image for the system may inadvertantly end up in a CXL
device that needs to be restored before the save state is recoverable.
I.e. a circular dependency that is not resolvable without a third party
save-area.

Arrange for the cxl_mem driver to fail S3 attempts. This still nominaly
allows for suspend, but requires unbinding all CXL memory devices before
the suspend to ensure the typical DRAM flow is taken. The cxl_mem unbind
flow is intended to also tear down all CXL memory regions associated
with a given cxl_memdev.

It is reasonable to assume that any device participating in a System RAM
range published in the EFI memory map is covered by aux power and
save-area outside the device itself. So this restriction can be
minimized in the future once pre-existing region enumeration support
arrives, and perhaps a spec update to clarify if the EFI memory map is
sufficent for determining the range of devices managed by
platform-firmware for S3 support.

Per Rafael, if the CXL configuration prevents suspend then it should
fail early before tasks are frozen, and mem_sleep should stop showing
'mem' as an option [1]. Effectively CXL augments the platform suspend
->valid() op since, for example, the ACPI ops are not aware of the CXL /
PCI dependencies. Given the split role of platform firmware vs OS
provisioned CXL memory it is up to the cxl_mem driver to determine if
the CXL configuration has elements that platform firmware may not be
prepared to restore.

Link: https://lore.kernel.org/r/CAJZ5v0hGVN_=3iU8OLpHY3Ak35T5+JcBM-qs8SbojKrpd0VXsA@mail.gmail.com [1]
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Len Brown <len.brown@intel.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lore.kernel.org/r/165066828317.3907920.5690432272182042556.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2022-04-22 16:09:42 -07:00
Haowen Bai
e5a3b0c5b6 PM: hibernate: Don't mark comment as kernel-doc
Change the comment to a normal (non-kernel-doc) comment to avoid
these kernel-doc warnings:

kernel/power/snapshot.c:335: warning: This comment starts with '/**', but
 isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
 * Data types related to memory bitmaps.

Signed-off-by: Haowen Bai <baihaowen@meizu.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-04-13 17:09:37 +02:00
Yang Li
467df4cfdc PM: hibernate: Fix some kernel-doc comments
Add parameter description in alloc_rtree_node()  kernel-doc
comment and fix several inconsistent function name descriptions.

Remove some warnings found by running scripts/kernel-doc,
which is caused by using 'make W=1'.

kernel/power/snapshot.c:438: warning: Function parameter or member
'gfp_mask' not described in 'alloc_rtree_node'
kernel/power/snapshot.c:438: warning: Function parameter or member
'safe_needed' not described in 'alloc_rtree_node'
kernel/power/snapshot.c:438: warning: Function parameter or member 'ca'
not described in 'alloc_rtree_node'
kernel/power/snapshot.c:438: warning: Function parameter or member
'list' not described in 'alloc_rtree_node'
kernel/power/snapshot.c:916: warning: expecting prototype for
memory_bm_rtree_next_pfn(). Prototype was for memory_bm_next_pfn()
instead
kernel/power/snapshot.c:1947: warning: expecting prototype for
alloc_highmem_image_pages(). Prototype was for alloc_highmem_pages()
instead
kernel/power/snapshot.c:2230: warning: expecting prototype for load
header(). Prototype was for load_header() instead

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
[ rjw: Comment adjustments to avoid line breaks ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-04-13 16:44:20 +02:00
David Cohen
ce1cb680ff PM: sleep: enable dynamic debug support within pm_pr_dbg()
Currently pm_pr_dbg() is used to filter kernel pm debug messages based
on pm_debug_messages_on flag. The problem is if we enable/disable this
flag it will affect all pm_pr_dbg() calls at once, so we can't
individually control them.

This patch changes pm_pr_dbg() implementation as such:

 - If pm_debug_messages_on is enabled, print the message.
 - If pm_debug_messages_on is disabled and CONFIG_DYNAMIC_DEBUG is
   enabled, only print the messages explicitly enabled on
   /sys/kernel/debug/dynamic_debug/control.
 - If pm_debug_messages_on is disabled and CONFIG_DYNAMIC_DEBUG is
   disabled, don't print the message.

Signed-off-by: David Cohen <dacohen@pm.me>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-04-13 16:34:01 +02:00
David Cohen
ae20cb9aec PM: sleep: Narrow down -DDEBUG on kernel/power/ files
The macro -DDEBUG is broadly enabled on kernel/power/ directory if
CONFIG_DYNAMIC_DEBUG is enabled. As side effect all debug messages using
pr_debug() and dev_dbg() are enabled by default on dynamic debug.
We're reworking pm_pr_dbg() to support dynamic debug, where pm_pr_dbg()
will print message if either pm_debug_messages_on flag is set or if it's
explicitly enabled on dynamic debug's control. That means if we let
-DDEBUG broadly set, the pm_debug_messages_on flag will be bypassed by
default on pm_pr_dbg() if dynamic debug is also enabled.

The files that directly use pr_debug() and dev_dbg() on kernel/power/ are:
 - swap.c
 - snapshot.c
 - energy_model.c

And those files do not use pm_pr_dbg(). So if we limit -DDEBUG to them,
we keep the same functional behavior while allowing the pm_pr_dbg()
refactor.

Signed-off-by: David Cohen <dacohen@pm.me>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-04-13 16:34:01 +02:00
Lukasz Luba
16857482b8 PM: EM: Remove old debugfs files and print all 'flags'
The Energy Model gets more bits used in 'flags'. Avoid adding another
debugfs file just to print what is the status of a new flag. Simply
remove old debugfs files and add one generic which prints all flags
as a hex value.

Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Reviewed-by: Ionela Voinescu <ionela.voinescu@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-04-13 16:26:17 +02:00
Lukasz Luba
75a3a99a5a PM: EM: Change the order of arguments in the .active_power() callback
The .active_power() callback passes the device pointer when it's called.
Aligned with a convetion present in other subsystems and pass the 'dev'
as a first argument. It looks more cleaner.

Adjust all affected drivers which implement that API callback.

Suggested-by: Ionela Voinescu <ionela.voinescu@arm.com>
Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Reviewed-by: Ionela Voinescu <ionela.voinescu@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-04-13 16:26:17 +02:00
Lukasz Luba
9136246311 PM: EM: Use the new .get_cost() callback while registering EM
The Energy Model (EM) allows to provide the 'cost' values when the device
driver provides the .get_cost() optional callback. This removes
restriction which is in the EM calculation function of the 'cost'
for each performance state. Now, the driver is in charge of providing
the right values which are then used by Energy Aware Scheduler.

Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Reviewed-by: Ionela Voinescu <ionela.voinescu@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-04-13 16:26:17 +02:00
Pierre Gondois
fc3a9a9858 PM: EM: Add artificial EM flag
The Energy Model (EM) can be used on platforms which are missing real
power information. Those platforms would implement .get_cost() which
populates needed values for the Energy Aware Scheduler (EAS). The EAS
doesn't use 'power' fields from EM, but other frameworks might use them.
Thus, to avoid miss-usage of this specific type of EM, introduce a new
flags which can be checked by other frameworks.

Signed-off-by: Pierre Gondois <Pierre.Gondois@arm.com>
Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Reviewed-by: Ionela Voinescu <ionela.voinescu@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-04-13 16:26:17 +02:00
Linus Torvalds
616355cc81 for-5.18/block-2022-03-18
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Merge tag 'for-5.18/block-2022-03-18' of git://git.kernel.dk/linux-block

Pull block updates from Jens Axboe:

 - BFQ cleanups and fixes (Yu, Zhang, Yahu, Paolo)

 - blk-rq-qos completion fix (Tejun)

 - blk-cgroup merge fix (Tejun)

 - Add offline error return value to distinguish it from an IO error on
   the device (Song)

 - IO stats fixes (Zhang, Christoph)

 - blkcg refcount fixes (Ming, Yu)

 - Fix for indefinite dispatch loop softlockup (Shin'ichiro)

 - blk-mq hardware queue management improvements (Ming)

 - sbitmap dead code removal (Ming, John)

 - Plugging merge improvements (me)

 - Show blk-crypto capabilities in sysfs (Eric)

 - Multiple delayed queue run improvement (David)

 - Block throttling fixes (Ming)

 - Start deprecating auto module loading based on dev_t (Christoph)

 - bio allocation improvements (Christoph, Chaitanya)

 - Get rid of bio_devname (Christoph)

 - bio clone improvements (Christoph)

 - Block plugging improvements (Christoph)

 - Get rid of genhd.h header (Christoph)

 - Ensure drivers use appropriate flush helpers (Christoph)

 - Refcounting improvements (Christoph)

 - Queue initialization and teardown improvements (Ming, Christoph)

 - Misc fixes/improvements (Barry, Chaitanya, Colin, Dan, Jiapeng,
   Lukas, Nian, Yang, Eric, Chengming)

* tag 'for-5.18/block-2022-03-18' of git://git.kernel.dk/linux-block: (127 commits)
  block: cancel all throttled bios in del_gendisk()
  block: let blkcg_gq grab request queue's refcnt
  block: avoid use-after-free on throttle data
  block: limit request dispatch loop duration
  block/bfq-iosched: Fix spelling mistake "tenative" -> "tentative"
  sr: simplify the local variable initialization in sr_block_open()
  block: don't merge across cgroup boundaries if blkcg is enabled
  block: fix rq-qos breakage from skipping rq_qos_done_bio()
  block: flush plug based on hardware and software queue order
  block: ensure plug merging checks the correct queue at least once
  block: move rq_qos_exit() into disk_release()
  block: do more work in elevator_exit
  block: move blk_exit_queue into disk_release
  block: move q_usage_counter release into blk_queue_release
  block: don't remove hctx debugfs dir from blk_mq_exit_queue
  block: move blkcg initialization/destroy into disk allocation/release handler
  sr: implement ->free_disk to simplify refcounting
  sd: implement ->free_disk to simplify refcounting
  sd: delay calling free_opal_dev
  sd: call sd_zbc_release_disk before releasing the scsi_device reference
  ...
2022-03-21 16:48:55 -07:00
Randy Dunlap
7a64ca17e4 PM: suspend: fix return value of __setup handler
If an invalid option is given for "test_suspend=<option>", the entire
string is added to init's environment, so return 1 instead of 0 from
the __setup handler.

  Unknown kernel command line parameters "BOOT_IMAGE=/boot/bzImage-517rc5
    test_suspend=invalid"

and

 Run /sbin/init as init process
   with arguments:
     /sbin/init
   with environment:
     HOME=/
     TERM=linux
     BOOT_IMAGE=/boot/bzImage-517rc5
     test_suspend=invalid

Fixes: 2ce986892f ("PM / sleep: Enhance test_suspend option with repeat capability")
Fixes: 27ddcc6596 ("PM / sleep: Add state field to pm_states[] entries")
Fixes: a9d7052363 ("PM: Separate suspend to RAM functionality from core")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: Igor Zhbanov <i.zhbanov@omprussia.ru>
Link: lore.kernel.org/r/64644a2f-4a20-bab3-1e15-3b2cdd0defe3@omprussia.ru
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-03-01 18:55:07 +01:00
Randy Dunlap
ba7ffcd4c4 PM: hibernate: fix __setup handler error handling
If an invalid value is used in "resumedelay=<seconds>", it is
silently ignored. Add a warning message and then let the __setup
handler return 1 to indicate that the kernel command line option
has been handled.

Fixes: 317cf7e5e8 ("PM / hibernate: convert simple_strtoul to kstrtoul")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: Igor Zhbanov <i.zhbanov@omprussia.ru>
Link: lore.kernel.org/r/64644a2f-4a20-bab3-1e15-3b2cdd0defe3@omprussia.ru
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-03-01 18:51:11 +01:00
Jiapeng Chong
444e1154b2 PM: hibernate: Clean up non-kernel-doc comments
Address the following W=1 kernel build warning:

kernel/power/swap.c:120: warning: This comment starts with '/**', but
isn't a kernel-doc comment. Refer
Documentation/doc-guide/kernel-doc.rst.

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-03-01 16:20:46 +01:00
Ye Bin
3f51aa9e29 PM: hibernate: fix load_image_and_restore() error path
As 'swsusp_check' open 'hib_resume_bdev', if call 'create_basic_memory_bitmaps'
failed, we need to close 'hib_resume_bdev' in 'load_image_and_restore' function.

Signed-off-by: Ye Bin <yebin10@huawei.com>
[ rjw: Subject ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-02-16 19:47:52 +01:00
Rafael J. Wysocki
cb1f65c1e1 PM: s2idle: ACPI: Fix wakeup interrupts handling
After commit e3728b50cd ("ACPI: PM: s2idle: Avoid possible race
related to the EC GPE") wakeup interrupts occurring immediately after
the one discarded by acpi_s2idle_wake() may be missed.  Moreover, if
the SCI triggers again immediately after the rearming in
acpi_s2idle_wake(), that wakeup may be missed too.

The problem is that pm_system_irq_wakeup() only calls pm_system_wakeup()
when pm_wakeup_irq is 0, but that's not the case any more after the
interrupt causing acpi_s2idle_wake() to run until pm_wakeup_irq is
cleared by the pm_wakeup_clear() call in s2idle_loop().  However,
there may be wakeup interrupts occurring in that time frame and if
that happens, they will be missed.

To address that issue first move the clearing of pm_wakeup_irq to
the point at which it is known that the interrupt causing
acpi_s2idle_wake() to tun will be discarded, before rearming the SCI
for wakeup.  Moreover, because that only reduces the size of the
time window in which the issue may manifest itself, allow
pm_system_irq_wakeup() to register two second wakeup interrupts in
a row and, when discarding the first one, replace it with the second
one.  [Of course, this assumes that only one wakeup interrupt can be
discarded in one go, but currently that is the case and I am not
aware of any plans to change that.]

Fixes: e3728b50cd ("ACPI: PM: s2idle: Avoid possible race related to the EC GPE")
Cc: 5.4+ <stable@vger.kernel.org> # 5.4+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-02-07 21:02:31 +01:00
Christoph Hellwig
07888c665b block: pass a block_device and opf to bio_alloc
Pass the block_device and operation that we plan to use this bio for to
bio_alloc to optimize the assignment.  NULL/0 can be passed, both for the
passthrough case on a raw request_queue and to temporarily avoid
refactoring some nasty code.

Also move the gfp_mask argument after the nr_vecs argument for a much
more logical calling convention matching what most of the kernel does.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220124091107.642561-18-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-02-02 07:49:59 -07:00
Christoph Hellwig
322cbb50de block: remove genhd.h
There is no good reason to keep genhd.h separate from the main blkdev.h
header that includes it.  So fold the contents of genhd.h into blkdev.h
and remove genhd.h entirely.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20220124093913.742411-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-02-02 07:49:59 -07:00
Amadeusz Sławiński
33569ef3c7 PM: hibernate: Remove register_nosave_region_late()
It is an unused wrapper forcing kmalloc allocation for registering
nosave regions. Also, rename __register_nosave_region() to
register_nosave_region() now that there is no need for disambiguation.

Signed-off-by: Amadeusz Sławiński <amadeuszx.slawinski@linux.intel.com>
Reviewed-by: Cezary Rojewski <cezary.rojewski@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-01-25 18:34:08 +01:00
Greg Kroah-Hartman
c9d967b2ce PM: wakeup: simplify the output logic of pm_show_wakelocks()
The buffer handling in pm_show_wakelocks() is tricky, and hopefully
correct.  Ensure it really is correct by using sysfs_emit_at() which
handles all of the tricky string handling logic in a PAGE_SIZE buffer
for us automatically as this is a sysfs file being read from.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-01-25 18:27:02 +01:00
David Woodhouse
74d9555580 PM: hibernate: Allow ACPI hardware signature to be honoured
Theoretically, when the hardware signature in FACS changes, the OS
is supposed to gracefully decline to attempt to resume from S4:

 "If the signature has changed, OSPM will not restore the system
  context and can boot from scratch"

In practice, Windows doesn't do this and many laptop vendors do allow
the signature to change especially when docking/undocking, so it would
be a bad idea to simply comply with the specification by default in the
general case.

However, there are use cases where we do want the compliant behaviour
and we know it's safe. Specifically, when resuming virtual machines where
we know the hypervisor has changed sufficiently that resume will fail.
We really want to be able to *tell* the guest kernel not to try, so it
boots cleanly and doesn't just crash. This patch provides a way to opt
in to the spec-compliant behaviour on the command line.

A follow-up patch may do this automatically for certain "known good"
machines based on a DMI match, or perhaps just for all hypervisor
guests since there's no good reason a hypervisor would change the
hardware_signature that it exposes to guests *unless* it wants them
to obey the ACPI specification.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-12-08 16:06:10 +01:00
Evan Green
88a5045f17 PM: hibernate: Fix snapshot partial write lengths
snapshot_write() is inappropriately limiting the amount of data that can
be written in cases where a partial page has already been written. For
example, one would expect to be able to write 1 byte, then 4095 bytes to
the snapshot device, and have both of those complete fully (since now
we're aligned to a page again). But what ends up happening is we write 1
byte, then 4094/4095 bytes complete successfully.

The reason is that simple_write_to_buffer()'s second argument is the
total size of the buffer, not the size of the buffer minus the offset.
Since simple_write_to_buffer() accounts for the offset in its
implementation, snapshot_write() can just pass the full page size
directly down.

Signed-off-by: Evan Green <evgreen@chromium.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-11-24 13:50:18 +01:00