talos-op-linux/kernel/power/user.c, branch v4.17

fs: add ksys_sync() helper; remove in-kernel calls to sys_sync()

2018-04-02T18:16:05+00:00

Using this helper allows us to avoid the in-kernel calls to the sys_sync() syscall. The ksys_ prefix denotes that this function is meant as a drop-in replacement for the syscall. In particular, it uses the same calling convention as sys_sync(). This patch is part of a series which removes in-kernel calls to syscalls. On this basis, the syscall entry path can be streamlined. For details, see http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net Cc: Alexander Viro Signed-off-by: Dominik Brodowski

Replace with globally

2016-12-24T19:46:01+00:00

This was entirely automated, using the script by Al: PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*' sed -i -e "s!$PATT!#include !" \ $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h) to do the replacement at the end of the merge window. Requested-by: Al Viro Signed-off-by: Linus Torvalds

PM / sleep: make PM notifiers called symmetrically

2016-06-27T22:38:55+00:00

This makes pm notifier PREPARE/POST symmetrical: if PREPARE fails, we will only undo what ever happened on PREPARE. It fixes the unbalanced CPU hotplug enable in CPU PM notifier. Signed-off-by: Lianwei Wang Signed-off-by: Rafael J. Wysocki

PM / hibernate: introduce "nohibernate" boot parameter

2014-06-16T21:29:39+00:00

To support using kernel features that are not compatible with hibernation, this creates the "nohibernate" kernel boot parameter to disable both hibernation and resume. This allows hibernation support to be a boot-time choice instead of only a compile-time choice. Signed-off-by: Kees Cook Acked-by: Pavel Machek Signed-off-by: Rafael J. Wysocki

Merge branch 'pm-sleep'

2013-11-19T00:07:08+00:00

* pm-sleep: PM / Hibernate: Do not crash kernel in free_basic_memory_bitmaps()

PM / Hibernate: Do not crash kernel in free_basic_memory_bitmaps()

2013-11-14T22:26:58+00:00

I have received a report about the BUG_ON() in free_basic_memory_bitmaps() triggering mysteriously during an aborted s2disk hibernation attempt. The only way I can explain that is that /dev/snapshot was first opened for writing (resume mode), then closed and then opened again for reading and closed again without freezing tasks. In that case the first invocation of snapshot_open() would set the free_bitmaps flag in snapshot_state, which is a static variable. That flag wouldn't be cleared later and the second invocation of snapshot_open() would just leave it like that, so the subsequent snapshot_release() would see data->frozen set and free_basic_memory_bitmaps() would be called unnecessarily. To prevent that from happening clear data->free_bitmaps in snapshot_open() when the file is being opened for reading (hibernate mode). In addition to that, replace the BUG_ON() in free_basic_memory_bitmaps() with a WARN_ON() as the kernel can continue just fine if the condition checked by that macro occurs. Fixes: aab172891542 (PM / hibernate: Fix user space driven resume regression) Reported-by: Oliver Lorenz Signed-off-by: Rafael J. Wysocki Cc: 3.12+ # 3.12+

PM / Hibernate: Use bool for boolean fields of struct snapshot_data

2013-10-18T20:20:40+00:00

The snapshot_data structure used internally by the hibernate user space interface code in user.c has three char fields that are used to store boolean values. Change their data type to bool and use true and false instead of 1 and 0, respectively, in assignments involving those fields. Signed-off-by: Rafael J. Wysocki

PM / hibernate: Fix user space driven resume regression

2013-09-30T17:40:56+00:00

Recent commit 8fd37a4 (PM / hibernate: Create memory bitmaps after freezing user space) broke the resume part of the user space driven hibernation (s2disk), because I forgot that the resume utility loaded the image into memory without freezing user space (it still freezes tasks after loading the image). This means that during user space driven resume we need to create the memory bitmaps at the "device open" time rather than at the "freeze tasks" time, so make that happen (that's a special case anyway, so it needs to be treated in a special way). Reported-and-tested-by: Ronald Signed-off-by: Rafael J. Wysocki

PM / hibernate / memory hotplug: Rework mutual exclusion

2013-08-31T00:49:47+00:00

Since all of the memory hotplug operations have to be carried out under device_hotplug_lock, they won't need to acquire pm_mutex if device_hotplug_lock is held around hibernation. For this reason, make the hibernation code acquire device_hotplug_lock after freezing user space processes and release it before thawing them. At the same tim drop the lock_system_sleep() and unlock_system_sleep() calls from lock_memory_hotplug() and unlock_memory_hotplug(), respectively. Signed-off-by: Rafael J. Wysocki Acked-by: Toshi Kani

PM / hibernate: Create memory bitmaps after freezing user space

2013-08-31T00:49:33+00:00

The hibernation core uses special memory bitmaps during image creation and restoration and traditionally those bitmaps are allocated before freezing tasks, because in the past GFP_KERNEL allocations might not work after all tasks had been frozen. However, this is an anachronism, because hibernation_snapshot() now calls hibernate_preallocate_memory() which allocates memory for the image upfront anyway, so the memory bitmaps may be allocated after freezing user space safely. For this reason, move all of the create_basic_memory_bitmaps() calls after freeze_processes() and all of the corresponding free_basic_memory_bitmaps() calls before thaw_processes(). This will allow us to hold device_hotplug_lock around hibernation without the need to worry about freezing issues with user space processes attempting to acquire it via sysfs attributes after the creation of memory bitmaps and before the freezing of tasks. Signed-off-by: Rafael J. Wysocki Acked-by: Toshi Kani