[ Upstream commit 29ab768277617452d88c0607c9299cdc63b6e9ff ]

The following code in pm_runtime_work() may dereference the dev->parent
pointer after the parent device has been freed:

	/* Maybe the parent is now able to suspend. */
	if (parent && !parent->power.ignore_children) {
		spin_unlock(&dev->power.lock);

		spin_lock(&parent->power.lock);
		rpm_idle(parent, RPM_ASYNC);
		spin_unlock(&parent->power.lock);

		spin_lock(&dev->power.lock);
	}

Fix this by inserting a flush_work() call in pm_runtime_remove().

Without this patch blktest block/001 triggers the following complaint
sporadically:

BUG: KASAN: slab-use-after-free in lock_acquire+0x70/0x160
Read of size 1 at addr ffff88812bef7198 by task kworker/u553:1/3081
Workqueue: pm pm_runtime_work
Call Trace:
 <TASK>
 dump_stack_lvl+0x61/0x80
 print_address_description.constprop.0+0x8b/0x310
 print_report+0xfd/0x1d7
 kasan_report+0xd8/0x1d0
 __kasan_check_byte+0x42/0x60
 lock_acquire.part.0+0x38/0x230
 lock_acquire+0x70/0x160
 _raw_spin_lock+0x36/0x50
 rpm_suspend+0xc6a/0xfe0
 rpm_idle+0x578/0x770
 pm_runtime_work+0xee/0x120
 process_one_work+0xde3/0x1410
 worker_thread+0x5eb/0xfe0
 kthread+0x37b/0x480
 ret_from_fork+0x6cb/0x920
 ret_from_fork_asm+0x11/0x20
 </TASK>

Allocated by task 4314:
 kasan_save_stack+0x2a/0x50
 kasan_save_track+0x18/0x40
 kasan_save_alloc_info+0x3d/0x50
 __kasan_kmalloc+0xa0/0xb0
 __kmalloc_noprof+0x311/0x990
 scsi_alloc_target+0x122/0xb60 [scsi_mod]
 __scsi_scan_target+0x101/0x460 [scsi_mod]
 scsi_scan_channel+0x179/0x1c0 [scsi_mod]
 scsi_scan_host_selected+0x259/0x2d0 [scsi_mod]
 store_scan+0x2d2/0x390 [scsi_mod]
 dev_attr_store+0x43/0x80
 sysfs_kf_write+0xde/0x140
 kernfs_fop_write_iter+0x3ef/0x670
 vfs_write+0x506/0x1470
 ksys_write+0xfd/0x230
 __x64_sys_write+0x76/0xc0
 x64_sys_call+0x213/0x1810
 do_syscall_64+0xee/0xfc0
 entry_SYSCALL_64_after_hwframe+0x4b/0x53

Freed by task 4314:
 kasan_save_stack+0x2a/0x50
 kasan_save_track+0x18/0x40
 kasan_save_free_info+0x3f/0x50
 __kasan_slab_free+0x67/0x80
 kfree+0x225/0x6c0
 scsi_target_dev_release+0x3d/0x60 [scsi_mod]
 device_release+0xa3/0x220
 kobject_cleanup+0x105/0x3a0
 kobject_put+0x72/0xd0
 put_device+0x17/0x20
 scsi_device_dev_release+0xacf/0x12c0 [scsi_mod]
 device_release+0xa3/0x220
 kobject_cleanup+0x105/0x3a0
 kobject_put+0x72/0xd0
 put_device+0x17/0x20
 scsi_device_put+0x7f/0xc0 [scsi_mod]
 sdev_store_delete+0xa5/0x120 [scsi_mod]
 dev_attr_store+0x43/0x80
 sysfs_kf_write+0xde/0x140
 kernfs_fop_write_iter+0x3ef/0x670
 vfs_write+0x506/0x1470
 ksys_write+0xfd/0x230
 __x64_sys_write+0x76/0xc0
 x64_sys_call+0x213/0x1810

Reported-by: Ming Lei <ming.lei@redhat.com>
Closes: https://lore.kernel.org/all/ZxdNvLNI8QaOfD2d@fedora/
Reported-by: syzbot+6c905ab800f20cf4086c@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/68c13942.050a0220.2ff435.000b.GAE@google.com/
Fixes: 5e928f77a09a ("PM: Introduce core framework for run-time PM of I/O devices (rev. 17)")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://patch.msgid.link/20260312182720.2776083-1-bvanassche@acm.org
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

commit 359afc8eb02a518fbdd0cbd462c8c2827c6cbec2 upstream.

Commit 89d9cec3b1e9 ("PM: runtime: Clear power.needs_force_resume in
pm_runtime_reinit()") added provisional clearing of power.needs_force_resume
to pm_runtime_reinit(), but it is done unconditionally which is a
mistake because pm_runtime_reinit() may race with driver probing
and removal [1].

To address this, notice that power.needs_force_resume should never
be set when runtime PM is enabled and so it only needs to be cleared
when runtime PM is disabled, and update pm_runtime_init() to only
clear that flag when runtime PM is disabled.

Fixes: 89d9cec3b1e9 ("PM: runtime: Clear power.needs_force_resume in pm_runtime_reinit()")
Reported-by: Ed Tsai <ed.tsai@mediatek.com>
Closes: https://lore.kernel.org/linux-pm/20251215122154.3180001-1-ed.tsai@mediatek.com/ [1]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: 6.17+ <stable@vger.kernel.org> # 6.17+
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://patch.msgid.link/12807571.O9o76ZdvQC@rafael.j.wysocki
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

[ Upstream commit 73db799bf5efc5a04654bb3ff6c9bf63a0dfa473 ]

Add `devm_pm_runtime_set_active_enabled()` and
`devm_pm_runtime_get_noresume()` for simplifying
common cases in drivers.

Signed-off-by: Bence Csókás <csokas.bence@prolan.hu>
Link: https://patch.msgid.link/20250327195928.680771-3-csokas.bence@prolan.hu
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Stable-dep-of: 0792c1984a45 ("iio: imu: inv_icm42600: Simplify pm_runtime setup")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 51888393cc64dd0462d0b96c13ab94873abbc030 upstream.

For all practical purposes, there is no difference between the situation
in which a given device is not ignoring children and its active child
count is nonzero and the situation in which its runtime PM usage counter
is nonzero.  However, pm_runtime_get_if_in_use() will only increment the
device's usage counter and return 1 in the latter case.

For consistency, make it do so in the former case either by adjusting
pm_runtime_get_conditional() and update the related kerneldoc comments
accordingly.

Fixes: c111566bea7c ("PM: runtime: Add pm_runtime_get_if_active()")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: 5.10+ <stable@vger.kernel.org> # 5.10+: c0ef3df8dbae: PM: runtime: Simplify pm_runtime_get_if_active() usage
Cc: 5.10+ <stable@vger.kernel.org> # 5.10+
Link: https://patch.msgid.link/12700973.O9o76ZdvQC@rjwysocki.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

[ Upstream commit 89d9cec3b1e9c49bae9375a2db6dc49bc7468af0 ]

Clear power.needs_force_resume in pm_runtime_reinit() in case it has
been set by pm_runtime_force_suspend() invoked from a driver remove
callback.

Suggested-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://patch.msgid.link/9495163.CDJkKcVGEf@rjwysocki.net
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit 40d3b40dce375d6f1c1dbf08d79eed3aed6c691d ]

pm_runtime_put_autosuspend() schedules a hrtimer to expire
at "dev->power.timer_expires". If the hrtimer's callback,
pm_suspend_timer_fn(), observes that the current time equals
"dev->power.timer_expires", it unexpectedly bails out instead of
proceeding with runtime suspend.

pm_suspend_timer_fn():

 if (expires > 0 && expires < ktime_get_mono_fast_ns()) {
 	dev->power.timer_expires = 0;
 	rpm_suspend(..)
 }

Additionally, as ->timer_expires is not cleared, all the future auto
suspend requests will not schedule hrtimer to perform auto suspend.

rpm_suspend():

 if ((rpmflags & RPM_AUTO) &&...) {
 	if (!(dev->power.timer_expires && ...) { <-- this will fail.
 		hrtimer_start_range_ns(&dev->power.suspend_timer,...);
 	}
 }

Fix this by as well checking if current time reaches the set expiration.

Co-developed-by: Patrick Daly <quic_pdaly@quicinc.com>
Signed-off-by: Patrick Daly <quic_pdaly@quicinc.com>
Signed-off-by: Charan Teja Kalla <quic_charante@quicinc.com>
Link: https://patch.msgid.link/20250515064125.1211561-1-quic_charante@quicinc.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit eeb87d17aceab7803a5a5bcb6cf2817b745157cf ]

The check before setting power.must_resume in device_suspend_noirq()
does not take power.child_count into account, but it should do that, so
use pm_runtime_need_not_resume() in it for this purpose and adjust the
comment next to it accordingly.

Fixes: 107d47b2b95e ("PM: sleep: core: Simplify the SMART_SUSPEND flag handling")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://patch.msgid.link/3353728.44csPzL39Z@rjwysocki.net
Signed-off-by: Sasha Levin <sashal@kernel.org>

Existing runtime PM ftrace events (`rpm_suspend`, `rpm_resume`,
`rpm_return_int`) offer limited visibility into the exact timing of device
runtime power state transitions, particularly when asynchronous operations
are involved. When the `rpm_suspend` or `rpm_resume` functions are invoked
with the `RPM_ASYNC` flag, a return value of 0 i.e., success merely
indicates that the device power state request has been queued, not that
the device has yet transitioned.

A new ftrace event, `rpm_status`, is introduced. This event directly logs
the `power.runtime_status` value of a device whenever it changes providing
granular tracking of runtime power state transitions regardless of
synchronous or asynchronous `rpm_suspend` / `rpm_resume` usage.

Signed-off-by: Vilas Bhat <vilasbhat@google.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

There are two ways to opportunistically increment a device's runtime PM
usage count, calling either pm_runtime_get_if_active() or
pm_runtime_get_if_in_use(). The former has an argument to tell whether to
ignore the usage count or not, and the latter simply calls the former with
ign_usage_count set to false. The other users that want to ignore the
usage_count will have to explicitly set that argument to true which is a
bit cumbersome.

To make this function more practical to use, remove the ign_usage_count
argument from the function. The main implementation is in a static
function called pm_runtime_get_conditional() and implementations of
pm_runtime_get_if_active() and pm_runtime_get_if_in_use() are moved to
runtime.c.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: Alex Elder <elder@linaro.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Takashi Iwai <tiwai@suse.de> # sound/
Reviewed-by: Jacek Lawrynowicz <jacek.lawrynowicz@linux.intel.com> # drivers/accel/ivpu/
Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com> # drivers/gpu/drm/i915/
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com> # drivers/pci/
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>