linux.git/kernel/power/swap.c, branch v5.10.258

PM: hibernate: Enforce ordering during image compression/decompression

2024-02-23T07:41:52+00:00

commit 71cd7e80cfde548959952eac7063aeaea1f2e1c6 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: 081a9d043c98 ("PM / Hibernate: Improve performance of LZO/plain hibernation, checksum image")
Cc: All applicable 
Signed-off-by: Hongchen Zhang 
Co-developed-by: Weihao Li 
Signed-off-by: Weihao Li 
[ rjw: Subject rewrite and changelog edits ]
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman

PM: hibernate: fix sparse warnings

2021-11-18T13:04:09+00:00

[ Upstream commit 01de5fcd8b1ac0ca28d2bb0921226a54fdd62684 ]

When building the kernel with sparse enabled 'C=1' the following
warnings shows up:

kernel/power/swap.c:390:29: warning: incorrect type in assignment (different base types)
kernel/power/swap.c:390:29:    expected int ret
kernel/power/swap.c:390:29:    got restricted blk_status_t

This is due to function hib_wait_io() returns a 'blk_status_t' which is
a bitwise u8. Commit 5416da01ff6e ("PM: hibernate: Remove
blk_status_to_errno in hib_wait_io") seemed to have mixed up the return
type. However, the 4e4cbee93d56 ("block: switch bios to blk_status_t")
actually broke the behaviour by returning the wrong type.

Rework so function hib_wait_io() returns a 'int' instead of
'blk_status_t' and make sure to call function
blk_status_to_errno(hb->error)' when returning from function
hib_wait_io() a int gets returned.

Fixes: 4e4cbee93d56 ("block: switch bios to blk_status_t")
Fixes: 5416da01ff6e ("PM: hibernate: Remove blk_status_to_errno in hib_wait_io")
Signed-off-by: Anders Roxell 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Sasha Levin

PM: hibernate: Get block device exclusively in swsusp_check()

2021-11-18T13:03:59+00:00

[ Upstream commit 39fbef4b0f77f9c89c8f014749ca533643a37c9f ]

The following kernel crash can be triggered:

[   89.266592] ------------[ cut here ]------------
[   89.267427] kernel BUG at fs/buffer.c:3020!
[   89.268264] invalid opcode: 0000 [#1] SMP KASAN PTI
[   89.269116] CPU: 7 PID: 1750 Comm: kmmpd-loop0 Not tainted 5.10.0-862.14.0.6.x86_64-08610-gc932cda3cef4-dirty #20
[   89.273169] RIP: 0010:submit_bh_wbc.isra.0+0x538/0x6d0
[   89.277157] RSP: 0018:ffff888105ddfd08 EFLAGS: 00010246
[   89.278093] RAX: 0000000000000005 RBX: ffff888124231498 RCX: ffffffffb2772612
[   89.279332] RDX: 1ffff11024846293 RSI: 0000000000000008 RDI: ffff888124231498
[   89.280591] RBP: ffff8881248cc000 R08: 0000000000000001 R09: ffffed1024846294
[   89.281851] R10: ffff88812423149f R11: ffffed1024846293 R12: 0000000000003800
[   89.283095] R13: 0000000000000001 R14: 0000000000000000 R15: ffff8881161f7000
[   89.284342] FS:  0000000000000000(0000) GS:ffff88839b5c0000(0000) knlGS:0000000000000000
[   89.285711] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   89.286701] CR2: 00007f166ebc01a0 CR3: 0000000435c0e000 CR4: 00000000000006e0
[   89.287919] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   89.289138] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   89.290368] Call Trace:
[   89.290842]  write_mmp_block+0x2ca/0x510
[   89.292218]  kmmpd+0x433/0x9a0
[   89.294902]  kthread+0x2dd/0x3e0
[   89.296268]  ret_from_fork+0x22/0x30
[   89.296906] Modules linked in:

by running the following commands:

 1. mkfs.ext4 -O mmp  /dev/sda -b 1024
 2. mount /dev/sda /home/test
 3. echo "/dev/sda" > /sys/power/resume

That happens because swsusp_check() calls set_blocksize() on the
target partition which confuses the file system:

       Thread1                       Thread2
mount /dev/sda /home/test
get s_mmp_bh  --> has mapped flag
start kmmpd thread
				echo "/dev/sda" > /sys/power/resume
				  resume_store
				    software_resume
				      swsusp_check
				        set_blocksize
					  truncate_inode_pages_range
					    truncate_cleanup_page
					      block_invalidatepage
					        discard_buffer --> clean mapped flag
write_mmp_block
  submit_bh
    submit_bh_wbc
      BUG_ON(!buffer_mapped(bh))

To address this issue, modify swsusp_check() to open the target block
device with exclusive access.

Signed-off-by: Ye Bin 
[ rjw: Subject and changelog edits ]
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Sasha Levin

PM: hibernate: flush swap writer after marking

2021-02-03T22:28:40+00:00

commit fef9c8d28e28a808274a18fbd8cc2685817fd62a upstream.

Flush the swap writer after, not before, marking the files, to ensure the
signature is properly written.

Fixes: 6f612af57821 ("PM / Hibernate: Group swap ops")
Signed-off-by: Laurent Badel 
Cc: All applicable 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman

Merge tag 'pm-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

2020-10-14T17:45:41+00:00

Pull power management updates from Rafael Wysocki:
 "These rework the collection of cpufreq statistics to allow it to take
  place if fast frequency switching is enabled in the governor, rework
  the frequency invariance handling in the cpufreq core and drivers, add
  new hardware support to a couple of cpufreq drivers, fix a number of
  assorted issues and clean up the code all over.

  Specifics:

   - Rework cpufreq statistics collection to allow it to take place when
     fast frequency switching is enabled in the governor (Viresh Kumar).

   - Make the cpufreq core set the frequency scale on behalf of the
     driver and update several cpufreq drivers accordingly (Ionela
     Voinescu, Valentin Schneider).

   - Add new hardware support to the STI and qcom cpufreq drivers and
     improve them (Alain Volmat, Manivannan Sadhasivam).

   - Fix multiple assorted issues in cpufreq drivers (Jon Hunter,
     Krzysztof Kozlowski, Matthias Kaehlcke, Pali Rohár, Stephan
     Gerhold, Viresh Kumar).

   - Fix several assorted issues in the operating performance points
     (OPP) framework (Stephan Gerhold, Viresh Kumar).

   - Allow devfreq drivers to fetch devfreq instances by DT enumeration
     instead of using explicit phandles and modify the devfreq core code
     to support driver-specific devfreq DT bindings (Leonard Crestez,
     Chanwoo Choi).

   - Improve initial hardware resetting in the tegra30 devfreq driver
     and clean up the tegra cpuidle driver (Dmitry Osipenko).

   - Update the cpuidle core to collect state entry rejection statistics
     and expose them via sysfs (Lina Iyer).

   - Improve the ACPI _CST code handling diagnostics (Chen Yu).

   - Update the PSCI cpuidle driver to allow the PM domain
     initialization to occur in the OSI mode as well as in the PC mode
     (Ulf Hansson).

   - Rework the generic power domains (genpd) core code to allow domain
     power off transition to be aborted in the absence of the "power
     off" domain callback (Ulf Hansson).

   - Fix two suspend-to-idle issues in the ACPI EC driver (Rafael
     Wysocki).

   - Fix the handling of timer_expires in the PM-runtime framework on
     32-bit systems and the handling of device links in it (Grygorii
     Strashko, Xiang Chen).

   - Add IO requests batching support to the hibernate image saving and
     reading code and drop a bogus get_gendisk() from there (Xiaoyi
     Chen, Christoph Hellwig).

   - Allow PCIe ports to be put into the D3cold power state if they are
     power-manageable via ACPI (Lukas Wunner).

   - Add missing header file include to a power capping driver (Pujin
     Shi).

   - Clean up the qcom-cpr AVS driver a bit (Liu Shixin).

   - Kevin Hilman steps down as designated reviwer of adaptive voltage
     scaling (AVS) drivers (Kevin Hilman)"

* tag 'pm-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (65 commits)
  cpufreq: stats: Fix string format specifier mismatch
  arm: disable frequency invariance for CONFIG_BL_SWITCHER
  cpufreq,arm,arm64: restructure definitions of arch_set_freq_scale()
  cpufreq: stats: Add memory barrier to store_reset()
  cpufreq: schedutil: Simplify sugov_fast_switch()
  ACPI: EC: PM: Drop ec_no_wakeup check from acpi_ec_dispatch_gpe()
  ACPI: EC: PM: Flush EC work unconditionally after wakeup
  PCI/ACPI: Whitelist hotplug ports for D3 if power managed by ACPI
  PM: hibernate: remove the bogus call to get_gendisk() in software_resume()
  cpufreq: Move traces and update to policy->cur to cpufreq core
  cpufreq: stats: Enable stats for fast-switch as well
  cpufreq: stats: Mark few conditionals with unlikely()
  cpufreq: stats: Remove locking
  cpufreq: stats: Defer stats update to cpufreq_stats_record_transition()
  PM: domains: Allow to abort power off when no ->power_off() callback
  PM: domains: Rename power state enums for genpd
  PM / devfreq: tegra30: Improve initial hardware resetting
  PM / devfreq: event: Change prototype of devfreq_event_get_edev_by_phandle function
  PM / devfreq: Change prototype of devfreq_get_devfreq_by_phandle function
  PM / devfreq: Add devfreq_get_devfreq_by_node function
  ...

PM: hibernate: Batch hibernate and resume IO requests

2020-09-28T13:58:18+00:00

Hibernate and resume process submits individual IO requests for each page
of the data, so use blk_plug to improve the batching of these requests.

Testing this change with hibernate and resumes consistently shows merging
of the IO requests and more than an order of magnitude improvement in
hibernate and resume speed is observed.

One hibernate and resume cycle for 16GB RAM out of 32GB in use takes
around 21 minutes before the change, and 1 minutes after the change on
a system with limited storage IOPS.

Signed-off-by: Xiaoyi Chen 
Co-Developed-by: Anchal Agarwal 
Signed-off-by: Anchal Agarwal 
[ rjw: Subject and changelog edits, white space damage fixes ]
Signed-off-by: Rafael J. Wysocki

PM: mm: cleanup swsusp_swap_check

2020-09-23T16:43:19+00:00

Use blkdev_get_by_dev instead of bdget + blkdev_get.

Signed-off-by: Christoph Hellwig 
Acked-by: Rafael J. Wysocki 
Signed-off-by: Jens Axboe

mm: split swap_type_of

2020-09-23T16:43:19+00:00

swap_type_of is used for two entirely different purposes:

 (1) check what swap type a given device/offset corresponds to
 (2) find the first available swap device that can be written to

Mixing both in a single function creates an unreadable mess.  Create two
separate functions instead, and switch both to pass a dev_t instead of
a struct block_device to further simplify the code.

Signed-off-by: Christoph Hellwig 
Signed-off-by: Jens Axboe

PM: hibernate: Add __init annotation to swsusp_header_init()

2020-06-05T11:52:38+00:00

'swsusp_header_init()' is only called via 'core_initcall'.
It can be marked as __init to save a few bytes of memory.

Signed-off-by: Christophe JAILLET 
[ rjw: Subject ]
Signed-off-by: Rafael J. Wysocki

kernel: power: swap: use kzalloc() instead of kmalloc() followed by memset()

2019-06-28T08:20:39+00:00

Use zeroing allocator instead of using allocator
followed with memset with 0

Signed-off-by: Fuqian Huang 
Acked-by: Pavel Machek 
[ rjw: Subject ]
Signed-off-by: Rafael J. Wysocki