user/sven/linux.git/drivers/base/power/runtime.c, branch v4.14.238

Revert "PM: runtime: Update device status before letting suppliers suspend"

2021-03-24T10:04:55Z

commit 0cab893f409c53634d0d818fa414641cbcdb0dab upstream. Revert commit 44cc89f76464 ("PM: runtime: Update device status before letting suppliers suspend") that introduced a race condition into __rpm_callback() which allowed a concurrent rpm_resume() to run and resume the device prematurely after its status had been changed to RPM_SUSPENDED by __rpm_callback(). Fixes: 44cc89f76464 ("PM: runtime: Update device status before letting suppliers suspend") Link: https://lore.kernel.org/linux-pm/24dfb6fc-5d54-6ee2-9195-26428b7ecf8a@intel.com/ Reported-by: Adrian Hunter Cc: 4.10+ # 4.10+ Signed-off-by: Rafael J. Wysocki Reviewed-by: Ulf Hansson Signed-off-by: Greg Kroah-Hartman

PM: runtime: Update device status before letting suppliers suspend

2021-03-11T12:51:04Z

commit 44cc89f764646b2f1f2ea5d1a08b230131707851 upstream. Because the PM-runtime status of the device is not updated in __rpm_callback(), attempts to suspend the suppliers of the given device triggered by rpm_put_suppliers() called by it may fail. Fix this by making __rpm_callback() update the device's status to RPM_SUSPENDED before calling rpm_put_suppliers() if the current status of the device is RPM_SUSPENDING and the callback just invoked by it has returned 0 (success). While at it, modify the code in __rpm_callback() to always check the device's PM-runtime status under its PM lock. Link: https://lore.kernel.org/linux-pm/CAPDyKFqm06KDw_p8WXsM4dijDbho4bb6T4k50UqqvR1_COsp8g@mail.gmail.com/ Fixes: 21d5c57b3726 ("PM / runtime: Use device links") Reported-by: Elaine Zhang Diagnosed-by: Ulf Hansson Signed-off-by: Rafael J. Wysocki Tested-by: Elaine Zhang Reviewed-by: Ulf Hansson Cc: 4.10+ # 4.10+ Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

PM / runtime: Fix handling of suppliers with disabled runtime PM

2018-02-25T10:07:58Z

[ Upstream commit 31eb7431805493e10f4731f366cf4d4e3e952035 ] Prevent rpm_get_suppliers() from returning an error code if runtime PM is disabled for one or more of the supplier devices it wants to runtime-resume, so as to make runtime PM work for devices with links to suppliers that don't use runtime PM (such links may be created during device enumeration even before it is known whether or not runtime PM will be enabled for the devices in question, for example). Fixes: 21d5c57b3726 (PM / runtime: Use device links) Reported-by: Adrian Hunter Signed-off-by: Rafael J. Wysocki Reviewed-by: Lukas Wunner Tested-by: Adrian Hunter Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

Revert "PM / QoS: Fix device resume latency PM QoS"

2017-10-31T17:35:40Z

This reverts commit 0cc2b4e5a020 (PM / QoS: Fix device resume latency PM QoS) as it introduced regressions on multiple systems and the fix-up in commit 2a9a86d5c813 (PM / QoS: Fix default runtime_pm device resume latency) does not address all of them. The original problem that commit 0cc2b4e5a020 was attempting to fix will be addressed later. Fixes: 0cc2b4e5a020 (PM / QoS: Fix device resume latency PM QoS) Reported-by: Geert Uytterhoeven Signed-off-by: Rafael J. Wysocki

PM / QoS: Fix device resume latency PM QoS

2017-10-24T13:20:45Z

The special value of 0 for device resume latency PM QoS means "no restriction", but there are two problems with that. First, device resume latency PM QoS requests with 0 as the value are always put in front of requests with positive values in the priority lists used internally by the PM QoS framework, causing 0 to be chosen as an effective constraint value. However, that 0 is then interpreted as "no restriction" effectively overriding the other requests with specific restrictions which is incorrect. Second, the users of device resume latency PM QoS have no way to specify that *any* resume latency at all should be avoided, which is an artificial limitation in general. To address these issues, modify device resume latency PM QoS to use S32_MAX as the "no constraint" value and 0 as the "no latency at all" one and rework its users (the cpuidle menu governor, the genpd QoS governor and the runtime PM framework) to follow these changes. Also add a special "n/a" value to the corresponding user space I/F to allow user space to indicate that it cannot accept any resume latencies at all for the given device. Fixes: 85dc0b8a4019 (PM / QoS: Make it possible to expose PM QoS latency constraints) Link: https://bugzilla.kernel.org/show_bug.cgi?id=197323 Reported-by: Reinette Chatre Tested-by: Reinette Chatre Signed-off-by: Rafael J. Wysocki Acked-by: Alex Shi Cc: All applicable

sched/headers: Prepare to move the memalloc_noio_*() APIs to

2017-03-02T07:42:33Z

Update the .c files that depend on these APIs. Acked-by: Linus Torvalds Cc: Mike Galbraith Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar

PM / runtime: Avoid false-positive warnings from might_sleep_if()

2017-02-03T23:44:36Z

The might_sleep_if() assertions in __pm_runtime_idle(), __pm_runtime_suspend() and __pm_runtime_resume() may generate false-positive warnings in some situations. For example, that happens if a nested pm_runtime_get_sync()/pm_runtime_put() pair is executed with disabled interrupts within an outer pm_runtime_get_sync()/pm_runtime_put() section for the same device. [Generally, pm_runtime_get_sync() may sleep, so it should not be called with disabled interrupts, but in this particular case the previous pm_runtime_get_sync() guarantees that the device will not be suspended, so the inner pm_runtime_get_sync() will return immediately after incrementing the device's usage counter.] That started to happen in the i915 driver in 4.10-rc, leading to the following splat: BUG: sleeping function called from invalid context at drivers/base/power/runtime.c:1032 in_atomic(): 1, irqs_disabled(): 0, pid: 1500, name: Xorg 1 lock held by Xorg/1500: #0: (&dev->struct_mutex){+.+.+.}, at: [] i915_mutex_lock_interruptible+0x43/0x140 [i915] CPU: 0 PID: 1500 Comm: Xorg Not tainted Call Trace: dump_stack+0x85/0xc2 ___might_sleep+0x196/0x260 __might_sleep+0x53/0xb0 __pm_runtime_resume+0x7a/0x90 intel_runtime_pm_get+0x25/0x90 [i915] aliasing_gtt_bind_vma+0xaa/0xf0 [i915] i915_vma_bind+0xaf/0x1e0 [i915] i915_gem_execbuffer_relocate_entry+0x513/0x6f0 [i915] i915_gem_execbuffer_relocate_vma.isra.34+0x188/0x250 [i915] ? trace_hardirqs_on+0xd/0x10 ? i915_gem_execbuffer_reserve_vma.isra.31+0x152/0x1f0 [i915] ? i915_gem_execbuffer_reserve.isra.32+0x372/0x3a0 [i915] i915_gem_do_execbuffer.isra.38+0xa70/0x1a40 [i915] ? __might_fault+0x4e/0xb0 i915_gem_execbuffer2+0xc5/0x260 [i915] ? __might_fault+0x4e/0xb0 drm_ioctl+0x206/0x450 [drm] ? i915_gem_execbuffer+0x340/0x340 [i915] ? __fget+0x5/0x200 do_vfs_ioctl+0x91/0x6f0 ? __fget+0x111/0x200 ? __fget+0x5/0x200 SyS_ioctl+0x79/0x90 entry_SYSCALL_64_fastpath+0x23/0xc6 even though the code triggering it is correct. Unfortunately, the might_sleep_if() assertions in question are too coarse-grained to cover such cases correctly, so make them a bit less sensitive in order to avoid the false-positives. Reported-and-tested-by: Sedat Dilek Signed-off-by: Rafael J. Wysocki

Merge tag 'driver-core-4.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

2016-12-13T19:42:18Z

Pull driver core updates from Greg KH: "Here's the new driver core patches for 4.10-rc1. Big thing here is the nice addition of "functional dependencies" to the driver core. The idea has been talked about for a very long time, great job to Rafael for stepping up and implementing it. It's been tested for longer than the 4.9-rc1 date, we held off on merging it earlier in order to feel more comfortable about it. Other than that, it's just a handful of small other patches, some good cleanups to the mess that is the firmware class code, and we have a test driver for the deferred probe logic. All of these have been in linux-next for a while with no reported issues" * tag 'driver-core-4.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (30 commits) firmware: Correct handling of fw_state_wait() return value driver core: Silence device links sphinx warning firmware: remove warning at documentation generation time drivers: base: dma-mapping: Fix typo in dmam_alloc_non_coherent comments driver core: test_async: fix up typo found by 0-day firmware: move fw_state_is_done() into UHM section firmware: do not use fw_lock for fw_state protection firmware: drop bit ops in favor of simple state machine firmware: refactor loading status firmware: fix usermode helper fallback loading driver core: firmware_class: convert to use class_groups driver core: devcoredump: convert to use class_groups driver core: class: add class_groups support kernfs: Declare two local data structures static driver-core: fix platform_no_drv_owner.cocci warnings drivers/base/memory.c: Remove unused 'first_page' variable driver core: add CLASS_ATTR_WO() drivers: base: cacheinfo: support DT overrides for cache properties drivers: base: cacheinfo: add pr_fmt logging drivers: base: cacheinfo: fix boot error message when acpi is enabled ...

PM / wakeirq: Fix dedicated wakeirq for drivers not using autosuspend

2016-12-06T22:45:59Z

I noticed some wakeirq flakeyness with consumer drivers not using autosuspend. For drivers not using autosuspend, the wakeirq may never get unmasked in rpm_suspend() because of irq desc->depth. We are configuring dedicated wakeirqs to start with IRQ_NOAUTOEN as we naturally don't want them running until rpm_suspend() is called. However, when a consumer driver initially calls pm_runtime_get(), we now wrongly start with disable_irq_nosync() call on the dedicated wakeirq that is disabled to start with. This causes desc->depth to toggle between 1 and 2 instead of the usual 0 and 1. This can prevent enable_irq() from unmasking the wakeirq as that only happens at desc->depth 1. This does not necessarily show up with drivers using autosuspend as there is time for disable_irq_nosync() before rpm_suspend() gets called after the autosuspend timeout. Let's fix the issue by adding wirq->status that lazily gets set on the first rpm_suspend(). We also need PM runtime core private functions for dev_pm_enable_wake_irq_check() and dev_pm_disable_wake_irq_check() so we can enable the dedicated wakeirq on the first rpm_suspend(). While at it, let's also fix the comments for dev_pm_enable_wake_irq() and dev_pm_disable_wake_irq(). Those can still be used by the consumer drivers as needed because the IRQ core manages the interrupt usecount for us. Fixes: 4990d4fe327b (PM / Wakeirq: Add automated device wake IRQ handling) Signed-off-by: Tony Lindgren Signed-off-by: Rafael J. Wysocki

PM / Runtime: Defer resuming of the device in pm_runtime_force_resume()

2016-11-18T23:15:39Z

When the pm_runtime_force_suspend|resume() helpers were invented, we still had CONFIG_PM_RUNTIME and CONFIG_PM_SLEEP as separate Kconfig options. To make sure these helpers worked for all combinations and without introducing too much of complexity, the device was always resumed in pm_runtime_force_resume(). More precisely, when CONFIG_PM_SLEEP was set and CONFIG_PM_RUNTIME was unset, we needed to resume the device as the subsystem/driver couldn't rely on using runtime PM to do it. As the CONFIG_PM_RUNTIME option was merged into CONFIG_PM a while ago, it removed this combination, of using CONFIG_PM_SLEEP without the earlier CONFIG_PM_RUNTIME. For this reason we can now rely on the subsystem/driver to use runtime PM to resume the device, instead of forcing that to be done in all cases. In other words, let's defer the runtime resume to a later point when it's actually needed. Signed-off-by: Ulf Hansson Tested-by: Marek Szyprowski Tested-by: Geert Uytterhoeven Acked-by: Kevin Hilman Signed-off-by: Rafael J. Wysocki