[Linux,v4.10.0-rc1+] Still call-traces after suspend-resume (pm? i915? cpu/hotplug?)

Commit Message

Rafael J. Wysocki Feb. 1, 2017, 12:22 a.m. UTC

On Mon, Jan 30, 2017 at 11:44 PM, Rafael J. Wysocki
<[e-mail]> wrote:
> On 1/24/2017 2:33 AM, Sedat Dilek wrote:
>>
>> On Fri, Dec 30, 2016 at 3:02 PM, Rafael J. Wysocki <[e-mail]>
>> wrote:
>>>
>>> On Fri, Dec 30, 2016 at 12:40 PM, Sedat Dilek <[e-mail]>
>>> wrote:
>>>>
>>>> Hi,
>>>>
>>>> I have already reported this issue in [1].
>>>> One of the issue was solved.
>>>> Unfortunately, it looks like there is still a different problem here
>>>> (Ubuntu/precise AMD64).
>>>>
>>>> I tried v4.10-rc1 and latest Linus tree up to...
>>>>
>>>> commit 98473f9f3f9bd404873cd1178c8be7d6d619f0d1
>>>> "mm/filemap: fix parameters to test_bit()"
>>>>
>>>> Here we go...
>>>>
>>>> [   29.636047] BUG: sleeping function called from invalid context at
>>>> drivers/base/power/runtime.c:1032
>>>> [   29.636055] in_atomic(): 1, irqs_disabled(): 0, pid: 1500, name: Xorg
>>>> [   29.636058] 1 lock held by Xorg/1500:
>>>> [   29.636060]  #0:  (&dev->struct_mutex){+.+.+.}, at:
>>>> [<ffffffffa0680c13>] i915_mutex_lock_interruptible+0x43/0x140 [i915]
>>>> [   29.636107] CPU: 0 PID: 1500 Comm: Xorg Not tainted
>>>> 4.10.0-rc1-6-iniza-amd64 #1
>>>> [   29.636109] Hardware name: SAMSUNG ELECTRONICS CO., LTD.
>>>> 530U3BI/530U4BI/530U4BH/530U3BI/530U4BI/530U4BH, BIOS 13XK 03/28/2013
>>>> [   29.636111] Call Trace:
>>>> [   29.636120]  dump_stack+0x85/0xc2
>>>> [   29.636124]  ___might_sleep+0x196/0x260
>>>> [   29.636127]  __might_sleep+0x53/0xb0
>>>> [   29.636131]  __pm_runtime_resume+0x7a/0x90
>>>> [   29.636159]  intel_runtime_pm_get+0x25/0x90 [i915]
>>>> [   29.636189]  aliasing_gtt_bind_vma+0xaa/0xf0 [i915]
>>>> [   29.636220]  i915_vma_bind+0xaf/0x1e0 [i915]
>>>> [   29.636248]  i915_gem_execbuffer_relocate_entry+0x513/0x6f0 [i915]
>>>> [   29.636272]  i915_gem_execbuffer_relocate_vma.isra.34+0x188/0x250
>>>> [i915]
>>>> [   29.636275]  ? trace_hardirqs_on+0xd/0x10
>>>> [   29.636294]  ? i915_gem_execbuffer_reserve_vma.isra.31+0x152/0x1f0
>>>> [i915]
>>>> [   29.636316]  ? i915_gem_execbuffer_reserve.isra.32+0x372/0x3a0 [i915]
>>>> [   29.636342]  i915_gem_do_execbuffer.isra.38+0xa70/0x1a40 [i915]
>>>> [   29.636347]  ? __might_fault+0x4e/0xb0
>>>> [   29.636373]  i915_gem_execbuffer2+0xc5/0x260 [i915]
>>>> [   29.636376]  ? __might_fault+0x4e/0xb0
>>>> [   29.636395]  drm_ioctl+0x206/0x450 [drm]
>>>> [   29.636420]  ? i915_gem_execbuffer+0x340/0x340 [i915]
>>>> [   29.636425]  ? __fget+0x5/0x200
>>>> [   29.636429]  do_vfs_ioctl+0x91/0x6f0
>>>> [   29.636431]  ? __fget+0x111/0x200
>>>> [   29.636433]  ? __fget+0x5/0x200
>>>> [   29.636436]  SyS_ioctl+0x79/0x90
>>>> [   29.636441]  entry_SYSCALL_64_fastpath+0x23/0xc6
>>>>
>>>> On suspend/resume I see the same call trace.
>>>> [2] points to the "BUG" line.
>>>
>>> Well, this appears to be an i915 issue, but not a serious one.
>>>
>>> Clearly, a function that may sleep (pm_runtime_get_sync() in
>>> intel_runtime_pm_get()) is called with disabled interrupts.  If I
>>> understand the code correctly, though, it actually is not going to
>>> sleep in this particular case, because pm_runtime_get_sync() has
>>> already been called once for this device in the same code path which
>>> means that this particular instance will return immediately, so this
>>> is a false-positive (most likely).
>>>
>>> Let me see if I the might_sleep_if() assertion in
>>> __pm_runtime_resume(() can be moved to a better place.
>>>
>> Hi Rafael,
>>
>> did you had a chance to look at this?
>> The problem still remains in Linux v4.10-rc5.
>
>
> No, I didn't.
>
> As I said, this is not a serious issue.

Something like the attached (untested).

Please try it and let me know if it makes the splat go away.

Thanks,
Rafael

Patch

---
 drivers/base/power/runtime.c |   11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

Index: linux-pm/drivers/base/power/runtime.c
===================================================================
--- linux-pm.orig/drivers/base/power/runtime.c
+++ linux-pm/drivers/base/power/runtime.c
@@ -966,13 +966,13 @@  int __pm_runtime_idle(struct device *dev
 	unsigned long flags;
 	int retval;
 
-	might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe);
-
 	if (rpmflags & RPM_GET_PUT) {
 		if (!atomic_dec_and_test(&dev->power.usage_count))
 			return 0;
 	}
 
+	might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe);
+
 	spin_lock_irqsave(&dev->power.lock, flags);
 	retval = rpm_idle(dev, rpmflags);
 	spin_unlock_irqrestore(&dev->power.lock, flags);
@@ -998,13 +998,13 @@  int __pm_runtime_suspend(struct device *
 	unsigned long flags;
 	int retval;
 
-	might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe);
-
 	if (rpmflags & RPM_GET_PUT) {
 		if (!atomic_dec_and_test(&dev->power.usage_count))
 			return 0;
 	}
 
+	might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe);
+
 	spin_lock_irqsave(&dev->power.lock, flags);
 	retval = rpm_suspend(dev, rpmflags);
 	spin_unlock_irqrestore(&dev->power.lock, flags);
@@ -1029,7 +1029,8 @@  int __pm_runtime_resume(struct device *d
 	unsigned long flags;
 	int retval;
 
-	might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe);
+	might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe &&
+			dev->power.runtime_status != RPM_ACTIVE);
 
 	if (rpmflags & RPM_GET_PUT)
 		atomic_inc(&dev->power.usage_count);