All of lore.kernel.org
 help / color / mirror / Atom feed
* [PATCH] rtc: cmos: Don't enable interrupts in the middle of the interrupt handler
@ 2016-10-19 18:02 ` ville.syrjala
  0 siblings, 0 replies; 12+ messages in thread
From: ville.syrjala @ 2016-10-19 18:02 UTC (permalink / raw)
  To: rtc-linux
  Cc: linux-kernel, intel-gfx, Gabriele Mazzotta, Alexandre Belloni,
	Ville Syrjälä

From: Ville Syrjälä <ville.syrjala@linux.intel.com>

Using spin_lock_irq()/spin_unlock_irq() from within the interrupt
handler is a no-no. Let's save/restore the flags to avoid turning on
interrupts prematurely.

We hit this in a bunch of our CI systems, but for whatever reason I
wasn't able to reproduce on my own machine, so this fix is just
based on the backtrace.

[  202.634918] WARNING: CPU: 0 PID: 0 at kernel/locking/lockdep.c:2729 trace_hardirqs_on_caller+0x113/0x1b0
[  202.634919] DEBUG_LOCKS_WARN_ON(current->hardirq_context)
[  202.634929] Modules linked in: snd_hda_intel i915 x86_pkg_temp_thermal intel_powerclamp coretemp crct10dif_pclmul crc32_pclmul ghash_clmulni_intel lpc_ich snd_hda_codec_realtek snd_hda_codec_generic snd_hda_codec_hdmi snd_hda_codec snd_hwdep i2c_designware_platform i2c_designware_core snd_hda_core mei_me mei snd_pcm r8169 mii sdhci_acpi sdhci mmc_core i2c_hid [last unloaded: i915]
[  202.634930] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G     U          4.9.0-rc1-CI-CI_DRM_1734+ #1
[  202.634931] Hardware name: GIGABYTE M4HM87P-00/M4HM87P-00, BIOS F6 12/10/2014
[  202.634933]  ffff88011ea03d68 ffffffff8142dce5 ffff88011ea03db8 0000000000000000
[  202.634934]  ffff88011ea03da8 ffffffff8107e496 00000aa900000002 ffffffff81e249a0
[  202.634935]  ffffffff81815637 ffffffff82e7c280 0000000000000000 0000000000000004
[  202.634936] Call Trace:
[  202.634939]  <IRQ>
[  202.634939]  [<ffffffff8142dce5>] dump_stack+0x67/0x92
[  202.634941]  [<ffffffff8107e496>] __warn+0xc6/0xe0
[  202.634944]  [<ffffffff81815637>] ? _raw_spin_unlock_irq+0x27/0x50
[  202.634945]  [<ffffffff8107e4fa>] warn_slowpath_fmt+0x4a/0x50
[  202.634946]  [<ffffffff810d6d83>] trace_hardirqs_on_caller+0x113/0x1b0
[  202.634948]  [<ffffffff810d6e2d>] trace_hardirqs_on+0xd/0x10
[  202.634949]  [<ffffffff81815637>] _raw_spin_unlock_irq+0x27/0x50
[  202.634951]  [<ffffffff81672042>] rtc_handler+0x32/0xa0
[  202.634954]  [<ffffffff814c08a3>] acpi_ev_fixed_event_detect+0xd4/0xfb
[  202.634956]  [<ffffffff814c2ccb>] acpi_ev_sci_xrupt_handler+0xf/0x2d
[  202.634957]  [<ffffffff814ab3ee>] acpi_irq+0x11/0x2c
[  202.634960]  [<ffffffff810e5288>] __handle_irq_event_percpu+0x58/0x370
[  202.634961]  [<ffffffff810e55be>] handle_irq_event_percpu+0x1e/0x50
[  202.634962]  [<ffffffff810e5624>] handle_irq_event+0x34/0x60
[  202.634963]  [<ffffffff810e8906>] handle_fasteoi_irq+0xa6/0x170
[  202.634966]  [<ffffffff8101eef5>] handle_irq+0x15/0x20
[  202.634967]  [<ffffffff8101e548>] do_IRQ+0x68/0x130
[  202.634968]  [<ffffffff81816789>] common_interrupt+0x89/0x89
[  202.634970]  <EOI>
[  202.634970]  [<ffffffff81814c73>] ? mwait_idle+0x93/0x210
[  202.634971]  [<ffffffff81814c6a>] ? mwait_idle+0x8a/0x210
[  202.634972]  [<ffffffff81026b0a>] arch_cpu_idle+0xa/0x10
[  202.634973]  [<ffffffff8181509e>] default_idle_call+0x1e/0x30
[  202.634974]  [<ffffffff810cbf6c>] cpu_startup_entry+0x17c/0x1f0
[  202.634976]  [<ffffffff8180ca87>] rest_init+0x127/0x130
[  202.634978]  [<ffffffff81f77f08>] start_kernel+0x3f6/0x403
[  202.634980]  [<ffffffff81f7728f>] x86_64_start_reservations+0x2a/0x2c
[  202.634981]  [<ffffffff81f77404>] x86_64_start_kernel+0x173/0x186
[  202.634982] ---[ end trace 293c99618fa08d34 ]---

Cc: Gabriele Mazzotta <gabriele.mzt@gmail.com>
Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Fixes: 983bf1256edb ("rtc: cmos: Clear ACPI-driven alarms upon resume")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
---
 drivers/rtc/rtc-cmos.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/rtc/rtc-cmos.c b/drivers/rtc/rtc-cmos.c
index dd3d59806ffa..19cd49ad92dc 100644
--- a/drivers/rtc/rtc-cmos.c
+++ b/drivers/rtc/rtc-cmos.c
@@ -996,8 +996,9 @@ static u32 rtc_handler(void *context)
 	struct cmos_rtc *cmos = dev_get_drvdata(dev);
 	unsigned char rtc_control = 0;
 	unsigned char rtc_intr;
+	unsigned long flags;
 
-	spin_lock_irq(&rtc_lock);
+	spin_lock_irqsave(&rtc_lock, flags);
 	if (cmos_rtc.suspend_ctrl)
 		rtc_control = CMOS_READ(RTC_CONTROL);
 	if (rtc_control & RTC_AIE) {
@@ -1006,7 +1007,7 @@ static u32 rtc_handler(void *context)
 		rtc_intr = CMOS_READ(RTC_INTR_FLAGS);
 		rtc_update_irq(cmos->rtc, 1, rtc_intr);
 	}
-	spin_unlock_irq(&rtc_lock);
+	spin_unlock_irqrestore(&rtc_lock, flags);
 
 	pm_wakeup_event(dev, 0);
 	acpi_clear_event(ACPI_EVENT_RTC);
-- 
2.7.4

^ permalink raw reply related	[flat|nested] 12+ messages in thread
* [rtc-linux] [PATCH] rtc: cmos: Don't enable interrupts in the middle of the interrupt handler
@ 2016-10-19 18:02 ` ville.syrjala
  0 siblings, 0 replies; 12+ messages in thread
From: ville.syrjala @ 2016-10-19 18:02 UTC (permalink / raw)
  To: rtc-linux
  Cc: linux-kernel, intel-gfx, Gabriele Mazzotta, Alexandre Belloni,
	Ville Syrjälä

From: Ville Syrj=C3=A4l=C3=A4 <ville.syrjala@linux.intel.com>

Using spin_lock_irq()/spin_unlock_irq() from within the interrupt
handler is a no-no. Let's save/restore the flags to avoid turning on
interrupts prematurely.

We hit this in a bunch of our CI systems, but for whatever reason I
wasn't able to reproduce on my own machine, so this fix is just
based on the backtrace.

[  202.634918] WARNING: CPU: 0 PID: 0 at kernel/locking/lockdep.c:2729 trac=
e_hardirqs_on_caller+0x113/0x1b0
[  202.634919] DEBUG_LOCKS_WARN_ON(current->hardirq_context)
[  202.634929] Modules linked in: snd_hda_intel i915 x86_pkg_temp_thermal i=
ntel_powerclamp coretemp crct10dif_pclmul crc32_pclmul ghash_clmulni_intel =
lpc_ich snd_hda_codec_realtek snd_hda_codec_generic snd_hda_codec_hdmi snd_=
hda_codec snd_hwdep i2c_designware_platform i2c_designware_core snd_hda_cor=
e mei_me mei snd_pcm r8169 mii sdhci_acpi sdhci mmc_core i2c_hid [last unlo=
aded: i915]
[  202.634930] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G     U          4.9.=
0-rc1-CI-CI_DRM_1734+ #1
[  202.634931] Hardware name: GIGABYTE M4HM87P-00/M4HM87P-00, BIOS F6 12/10=
/2014
[  202.634933]  ffff88011ea03d68 ffffffff8142dce5 ffff88011ea03db8 00000000=
00000000
[  202.634934]  ffff88011ea03da8 ffffffff8107e496 00000aa900000002 ffffffff=
81e249a0
[  202.634935]  ffffffff81815637 ffffffff82e7c280 0000000000000000 00000000=
00000004
[  202.634936] Call Trace:
[  202.634939]  <IRQ>
[  202.634939]  [<ffffffff8142dce5>] dump_stack+0x67/0x92
[  202.634941]  [<ffffffff8107e496>] __warn+0xc6/0xe0
[  202.634944]  [<ffffffff81815637>] ? _raw_spin_unlock_irq+0x27/0x50
[  202.634945]  [<ffffffff8107e4fa>] warn_slowpath_fmt+0x4a/0x50
[  202.634946]  [<ffffffff810d6d83>] trace_hardirqs_on_caller+0x113/0x1b0
[  202.634948]  [<ffffffff810d6e2d>] trace_hardirqs_on+0xd/0x10
[  202.634949]  [<ffffffff81815637>] _raw_spin_unlock_irq+0x27/0x50
[  202.634951]  [<ffffffff81672042>] rtc_handler+0x32/0xa0
[  202.634954]  [<ffffffff814c08a3>] acpi_ev_fixed_event_detect+0xd4/0xfb
[  202.634956]  [<ffffffff814c2ccb>] acpi_ev_sci_xrupt_handler+0xf/0x2d
[  202.634957]  [<ffffffff814ab3ee>] acpi_irq+0x11/0x2c
[  202.634960]  [<ffffffff810e5288>] __handle_irq_event_percpu+0x58/0x370
[  202.634961]  [<ffffffff810e55be>] handle_irq_event_percpu+0x1e/0x50
[  202.634962]  [<ffffffff810e5624>] handle_irq_event+0x34/0x60
[  202.634963]  [<ffffffff810e8906>] handle_fasteoi_irq+0xa6/0x170
[  202.634966]  [<ffffffff8101eef5>] handle_irq+0x15/0x20
[  202.634967]  [<ffffffff8101e548>] do_IRQ+0x68/0x130
[  202.634968]  [<ffffffff81816789>] common_interrupt+0x89/0x89
[  202.634970]  <EOI>
[  202.634970]  [<ffffffff81814c73>] ? mwait_idle+0x93/0x210
[  202.634971]  [<ffffffff81814c6a>] ? mwait_idle+0x8a/0x210
[  202.634972]  [<ffffffff81026b0a>] arch_cpu_idle+0xa/0x10
[  202.634973]  [<ffffffff8181509e>] default_idle_call+0x1e/0x30
[  202.634974]  [<ffffffff810cbf6c>] cpu_startup_entry+0x17c/0x1f0
[  202.634976]  [<ffffffff8180ca87>] rest_init+0x127/0x130
[  202.634978]  [<ffffffff81f77f08>] start_kernel+0x3f6/0x403
[  202.634980]  [<ffffffff81f7728f>] x86_64_start_reservations+0x2a/0x2c
[  202.634981]  [<ffffffff81f77404>] x86_64_start_kernel+0x173/0x186
[  202.634982] ---[ end trace 293c99618fa08d34 ]---

Cc: Gabriele Mazzotta <gabriele.mzt@gmail.com>
Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Fixes: 983bf1256edb ("rtc: cmos: Clear ACPI-driven alarms upon resume")
Signed-off-by: Ville Syrj=C3=A4l=C3=A4 <ville.syrjala@linux.intel.com>
---
 drivers/rtc/rtc-cmos.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/rtc/rtc-cmos.c b/drivers/rtc/rtc-cmos.c
index dd3d59806ffa..19cd49ad92dc 100644
--- a/drivers/rtc/rtc-cmos.c
+++ b/drivers/rtc/rtc-cmos.c
@@ -996,8 +996,9 @@ static u32 rtc_handler(void *context)
 	struct cmos_rtc *cmos =3D dev_get_drvdata(dev);
 	unsigned char rtc_control =3D 0;
 	unsigned char rtc_intr;
+	unsigned long flags;
=20
-	spin_lock_irq(&rtc_lock);
+	spin_lock_irqsave(&rtc_lock, flags);
 	if (cmos_rtc.suspend_ctrl)
 		rtc_control =3D CMOS_READ(RTC_CONTROL);
 	if (rtc_control & RTC_AIE) {
@@ -1006,7 +1007,7 @@ static u32 rtc_handler(void *context)
 		rtc_intr =3D CMOS_READ(RTC_INTR_FLAGS);
 		rtc_update_irq(cmos->rtc, 1, rtc_intr);
 	}
-	spin_unlock_irq(&rtc_lock);
+	spin_unlock_irqrestore(&rtc_lock, flags);
=20
 	pm_wakeup_event(dev, 0);
 	acpi_clear_event(ACPI_EVENT_RTC);
--=20
2.7.4

--=20
You received this message because you are subscribed to "rtc-linux".
Membership options at http://groups.google.com/group/rtc-linux .
Please read http://groups.google.com/group/rtc-linux/web/checklist
before submitting a driver.
---=20
You received this message because you are subscribed to the Google Groups "=
rtc-linux" group.
To unsubscribe from this group and stop receiving emails from it, send an e=
mail to rtc-linux+unsubscribe@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.

^ permalink raw reply related	[flat|nested] 12+ messages in thread
* [PATCH] rtc: cmos: Don't enable interrupts in the middle of the interrupt handler
@ 2016-10-19 18:02 ` ville.syrjala
  0 siblings, 0 replies; 12+ messages in thread
From: ville.syrjala-VuQAYsv1563Yd54FQh9/CA @ 2016-10-19 18:02 UTC (permalink / raw)
  To: rtc-linux-/JYPxA39Uh5TLH3MbocFFw
  Cc: linux-kernel-u79uwXL29TY76Z2rM5mHXA,
	intel-gfx-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW, Gabriele Mazzotta,
	Alexandre Belloni, Ville Syrjälä

From: Ville Syrjälä <ville.syrjala-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>

Using spin_lock_irq()/spin_unlock_irq() from within the interrupt
handler is a no-no. Let's save/restore the flags to avoid turning on
interrupts prematurely.

We hit this in a bunch of our CI systems, but for whatever reason I
wasn't able to reproduce on my own machine, so this fix is just
based on the backtrace.

[  202.634918] WARNING: CPU: 0 PID: 0 at kernel/locking/lockdep.c:2729 trace_hardirqs_on_caller+0x113/0x1b0
[  202.634919] DEBUG_LOCKS_WARN_ON(current->hardirq_context)
[  202.634929] Modules linked in: snd_hda_intel i915 x86_pkg_temp_thermal intel_powerclamp coretemp crct10dif_pclmul crc32_pclmul ghash_clmulni_intel lpc_ich snd_hda_codec_realtek snd_hda_codec_generic snd_hda_codec_hdmi snd_hda_codec snd_hwdep i2c_designware_platform i2c_designware_core snd_hda_core mei_me mei snd_pcm r8169 mii sdhci_acpi sdhci mmc_core i2c_hid [last unloaded: i915]
[  202.634930] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G     U          4.9.0-rc1-CI-CI_DRM_1734+ #1
[  202.634931] Hardware name: GIGABYTE M4HM87P-00/M4HM87P-00, BIOS F6 12/10/2014
[  202.634933]  ffff88011ea03d68 ffffffff8142dce5 ffff88011ea03db8 0000000000000000
[  202.634934]  ffff88011ea03da8 ffffffff8107e496 00000aa900000002 ffffffff81e249a0
[  202.634935]  ffffffff81815637 ffffffff82e7c280 0000000000000000 0000000000000004
[  202.634936] Call Trace:
[  202.634939]  <IRQ>
[  202.634939]  [<ffffffff8142dce5>] dump_stack+0x67/0x92
[  202.634941]  [<ffffffff8107e496>] __warn+0xc6/0xe0
[  202.634944]  [<ffffffff81815637>] ? _raw_spin_unlock_irq+0x27/0x50
[  202.634945]  [<ffffffff8107e4fa>] warn_slowpath_fmt+0x4a/0x50
[  202.634946]  [<ffffffff810d6d83>] trace_hardirqs_on_caller+0x113/0x1b0
[  202.634948]  [<ffffffff810d6e2d>] trace_hardirqs_on+0xd/0x10
[  202.634949]  [<ffffffff81815637>] _raw_spin_unlock_irq+0x27/0x50
[  202.634951]  [<ffffffff81672042>] rtc_handler+0x32/0xa0
[  202.634954]  [<ffffffff814c08a3>] acpi_ev_fixed_event_detect+0xd4/0xfb
[  202.634956]  [<ffffffff814c2ccb>] acpi_ev_sci_xrupt_handler+0xf/0x2d
[  202.634957]  [<ffffffff814ab3ee>] acpi_irq+0x11/0x2c
[  202.634960]  [<ffffffff810e5288>] __handle_irq_event_percpu+0x58/0x370
[  202.634961]  [<ffffffff810e55be>] handle_irq_event_percpu+0x1e/0x50
[  202.634962]  [<ffffffff810e5624>] handle_irq_event+0x34/0x60
[  202.634963]  [<ffffffff810e8906>] handle_fasteoi_irq+0xa6/0x170
[  202.634966]  [<ffffffff8101eef5>] handle_irq+0x15/0x20
[  202.634967]  [<ffffffff8101e548>] do_IRQ+0x68/0x130
[  202.634968]  [<ffffffff81816789>] common_interrupt+0x89/0x89
[  202.634970]  <EOI>
[  202.634970]  [<ffffffff81814c73>] ? mwait_idle+0x93/0x210
[  202.634971]  [<ffffffff81814c6a>] ? mwait_idle+0x8a/0x210
[  202.634972]  [<ffffffff81026b0a>] arch_cpu_idle+0xa/0x10
[  202.634973]  [<ffffffff8181509e>] default_idle_call+0x1e/0x30
[  202.634974]  [<ffffffff810cbf6c>] cpu_startup_entry+0x17c/0x1f0
[  202.634976]  [<ffffffff8180ca87>] rest_init+0x127/0x130
[  202.634978]  [<ffffffff81f77f08>] start_kernel+0x3f6/0x403
[  202.634980]  [<ffffffff81f7728f>] x86_64_start_reservations+0x2a/0x2c
[  202.634981]  [<ffffffff81f77404>] x86_64_start_kernel+0x173/0x186
[  202.634982] ---[ end trace 293c99618fa08d34 ]---

Cc: Gabriele Mazzotta <gabriele.mzt-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Cc: Alexandre Belloni <alexandre.belloni-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org>
Fixes: 983bf1256edb ("rtc: cmos: Clear ACPI-driven alarms upon resume")
Signed-off-by: Ville Syrjälä <ville.syrjala-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
---
 drivers/rtc/rtc-cmos.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/rtc/rtc-cmos.c b/drivers/rtc/rtc-cmos.c
index dd3d59806ffa..19cd49ad92dc 100644
--- a/drivers/rtc/rtc-cmos.c
+++ b/drivers/rtc/rtc-cmos.c
@@ -996,8 +996,9 @@ static u32 rtc_handler(void *context)
 	struct cmos_rtc *cmos = dev_get_drvdata(dev);
 	unsigned char rtc_control = 0;
 	unsigned char rtc_intr;
+	unsigned long flags;
 
-	spin_lock_irq(&rtc_lock);
+	spin_lock_irqsave(&rtc_lock, flags);
 	if (cmos_rtc.suspend_ctrl)
 		rtc_control = CMOS_READ(RTC_CONTROL);
 	if (rtc_control & RTC_AIE) {
@@ -1006,7 +1007,7 @@ static u32 rtc_handler(void *context)
 		rtc_intr = CMOS_READ(RTC_INTR_FLAGS);
 		rtc_update_irq(cmos->rtc, 1, rtc_intr);
 	}
-	spin_unlock_irq(&rtc_lock);
+	spin_unlock_irqrestore(&rtc_lock, flags);
 
 	pm_wakeup_event(dev, 0);
 	acpi_clear_event(ACPI_EVENT_RTC);
-- 
2.7.4

-- 
You received this message because you are subscribed to "rtc-linux".
Membership options at http://groups.google.com/group/rtc-linux .
Please read http://groups.google.com/group/rtc-linux/web/checklist
before submitting a driver.
--- 
You received this message because you are subscribed to the Google Groups "rtc-linux" group.
To unsubscribe from this group and stop receiving emails from it, send an email to rtc-linux+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org
For more options, visit https://groups.google.com/d/optout.

^ permalink raw reply related	[flat|nested] 12+ messages in thread
* Re: [Intel-gfx] [PATCH] rtc: cmos: Don't enable interrupts in the middle of the interrupt handler
  2016-10-19 18:02 ` [rtc-linux] " ville.syrjala
  (?)
@ 2016-10-19 18:16   ` Chris Wilson
  -1 siblings, 0 replies; 12+ messages in thread
From: Chris Wilson @ 2016-10-19 18:16 UTC (permalink / raw)
  To: ville.syrjala
  Cc: rtc-linux, intel-gfx, Gabriele Mazzotta, Alexandre Belloni, linux-kernel

On Wed, Oct 19, 2016 at 09:02:04PM +0300, ville.syrjala@linux.intel.com wrote:
> From: Ville Syrjälä <ville.syrjala@linux.intel.com>
> 
> Using spin_lock_irq()/spin_unlock_irq() from within the interrupt
> handler is a no-no. Let's save/restore the flags to avoid turning on
> interrupts prematurely.
> 
> We hit this in a bunch of our CI systems, but for whatever reason I
> wasn't able to reproduce on my own machine, so this fix is just
> based on the backtrace.
> 
> [  202.634918] WARNING: CPU: 0 PID: 0 at kernel/locking/lockdep.c:2729 trace_hardirqs_on_caller+0x113/0x1b0
> [  202.634919] DEBUG_LOCKS_WARN_ON(current->hardirq_context)
> [  202.634929] Modules linked in: snd_hda_intel i915 x86_pkg_temp_thermal intel_powerclamp coretemp crct10dif_pclmul crc32_pclmul ghash_clmulni_intel lpc_ich snd_hda_codec_realtek snd_hda_codec_generic snd_hda_codec_hdmi snd_hda_codec snd_hwdep i2c_designware_platform i2c_designware_core snd_hda_core mei_me mei snd_pcm r8169 mii sdhci_acpi sdhci mmc_core i2c_hid [last unloaded: i915]
> [  202.634930] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G     U          4.9.0-rc1-CI-CI_DRM_1734+ #1
> [  202.634931] Hardware name: GIGABYTE M4HM87P-00/M4HM87P-00, BIOS F6 12/10/2014
> [  202.634933]  ffff88011ea03d68 ffffffff8142dce5 ffff88011ea03db8 0000000000000000
> [  202.634934]  ffff88011ea03da8 ffffffff8107e496 00000aa900000002 ffffffff81e249a0
> [  202.634935]  ffffffff81815637 ffffffff82e7c280 0000000000000000 0000000000000004
> [  202.634936] Call Trace:
> [  202.634939]  <IRQ>
> [  202.634939]  [<ffffffff8142dce5>] dump_stack+0x67/0x92
> [  202.634941]  [<ffffffff8107e496>] __warn+0xc6/0xe0
> [  202.634944]  [<ffffffff81815637>] ? _raw_spin_unlock_irq+0x27/0x50
> [  202.634945]  [<ffffffff8107e4fa>] warn_slowpath_fmt+0x4a/0x50
> [  202.634946]  [<ffffffff810d6d83>] trace_hardirqs_on_caller+0x113/0x1b0
> [  202.634948]  [<ffffffff810d6e2d>] trace_hardirqs_on+0xd/0x10
> [  202.634949]  [<ffffffff81815637>] _raw_spin_unlock_irq+0x27/0x50
> [  202.634951]  [<ffffffff81672042>] rtc_handler+0x32/0xa0
> [  202.634954]  [<ffffffff814c08a3>] acpi_ev_fixed_event_detect+0xd4/0xfb
> [  202.634956]  [<ffffffff814c2ccb>] acpi_ev_sci_xrupt_handler+0xf/0x2d
> [  202.634957]  [<ffffffff814ab3ee>] acpi_irq+0x11/0x2c
> [  202.634960]  [<ffffffff810e5288>] __handle_irq_event_percpu+0x58/0x370
> [  202.634961]  [<ffffffff810e55be>] handle_irq_event_percpu+0x1e/0x50
> [  202.634962]  [<ffffffff810e5624>] handle_irq_event+0x34/0x60
> [  202.634963]  [<ffffffff810e8906>] handle_fasteoi_irq+0xa6/0x170
> [  202.634966]  [<ffffffff8101eef5>] handle_irq+0x15/0x20
> [  202.634967]  [<ffffffff8101e548>] do_IRQ+0x68/0x130
> [  202.634968]  [<ffffffff81816789>] common_interrupt+0x89/0x89
> [  202.634970]  <EOI>
> [  202.634970]  [<ffffffff81814c73>] ? mwait_idle+0x93/0x210
> [  202.634971]  [<ffffffff81814c6a>] ? mwait_idle+0x8a/0x210
> [  202.634972]  [<ffffffff81026b0a>] arch_cpu_idle+0xa/0x10
> [  202.634973]  [<ffffffff8181509e>] default_idle_call+0x1e/0x30
> [  202.634974]  [<ffffffff810cbf6c>] cpu_startup_entry+0x17c/0x1f0
> [  202.634976]  [<ffffffff8180ca87>] rest_init+0x127/0x130
> [  202.634978]  [<ffffffff81f77f08>] start_kernel+0x3f6/0x403
> [  202.634980]  [<ffffffff81f7728f>] x86_64_start_reservations+0x2a/0x2c
> [  202.634981]  [<ffffffff81f77404>] x86_64_start_kernel+0x173/0x186
> [  202.634982] ---[ end trace 293c99618fa08d34 ]---
> 
> Cc: Gabriele Mazzotta <gabriele.mzt@gmail.com>
> Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com>
> Fixes: 983bf1256edb ("rtc: cmos: Clear ACPI-driven alarms upon resume")
> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
> ---
>  drivers/rtc/rtc-cmos.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/rtc/rtc-cmos.c b/drivers/rtc/rtc-cmos.c
> index dd3d59806ffa..19cd49ad92dc 100644
> --- a/drivers/rtc/rtc-cmos.c
> +++ b/drivers/rtc/rtc-cmos.c
> @@ -996,8 +996,9 @@ static u32 rtc_handler(void *context)
>  	struct cmos_rtc *cmos = dev_get_drvdata(dev);
>  	unsigned char rtc_control = 0;
>  	unsigned char rtc_intr;
> +	unsigned long flags;
>  
> -	spin_lock_irq(&rtc_lock);
> +	spin_lock_irqsave(&rtc_lock, flags);

My reading of the acpi fixed event handlers suggests that this can only
be called from interrupt context.

Anyway using irqsave is correct (just may be optimised away to a plain
spin_lock() if the condition that this is only called in irq context is
satisfied).

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre

^ permalink raw reply	[flat|nested] 12+ messages in thread
* [rtc-linux] Re: [Intel-gfx] [PATCH] rtc: cmos: Don't enable interrupts in the middle of the interrupt handler
@ 2016-10-19 18:16   ` Chris Wilson
  0 siblings, 0 replies; 12+ messages in thread
From: Chris Wilson @ 2016-10-19 18:16 UTC (permalink / raw)
  To: ville.syrjala
  Cc: rtc-linux, intel-gfx, Gabriele Mazzotta, Alexandre Belloni, linux-kernel

On Wed, Oct 19, 2016 at 09:02:04PM +0300, ville.syrjala@linux.intel.com wro=
te:
> From: Ville Syrj=C3=A4l=C3=A4 <ville.syrjala@linux.intel.com>
>=20
> Using spin_lock_irq()/spin_unlock_irq() from within the interrupt
> handler is a no-no. Let's save/restore the flags to avoid turning on
> interrupts prematurely.
>=20
> We hit this in a bunch of our CI systems, but for whatever reason I
> wasn't able to reproduce on my own machine, so this fix is just
> based on the backtrace.
>=20
> [  202.634918] WARNING: CPU: 0 PID: 0 at kernel/locking/lockdep.c:2729 tr=
ace_hardirqs_on_caller+0x113/0x1b0
> [  202.634919] DEBUG_LOCKS_WARN_ON(current->hardirq_context)
> [  202.634929] Modules linked in: snd_hda_intel i915 x86_pkg_temp_thermal=
 intel_powerclamp coretemp crct10dif_pclmul crc32_pclmul ghash_clmulni_inte=
l lpc_ich snd_hda_codec_realtek snd_hda_codec_generic snd_hda_codec_hdmi sn=
d_hda_codec snd_hwdep i2c_designware_platform i2c_designware_core snd_hda_c=
ore mei_me mei snd_pcm r8169 mii sdhci_acpi sdhci mmc_core i2c_hid [last un=
loaded: i915]
> [  202.634930] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G     U          4.=
9.0-rc1-CI-CI_DRM_1734+ #1
> [  202.634931] Hardware name: GIGABYTE M4HM87P-00/M4HM87P-00, BIOS F6 12/=
10/2014
> [  202.634933]  ffff88011ea03d68 ffffffff8142dce5 ffff88011ea03db8 000000=
0000000000
> [  202.634934]  ffff88011ea03da8 ffffffff8107e496 00000aa900000002 ffffff=
ff81e249a0
> [  202.634935]  ffffffff81815637 ffffffff82e7c280 0000000000000000 000000=
0000000004
> [  202.634936] Call Trace:
> [  202.634939]  <IRQ>
> [  202.634939]  [<ffffffff8142dce5>] dump_stack+0x67/0x92
> [  202.634941]  [<ffffffff8107e496>] __warn+0xc6/0xe0
> [  202.634944]  [<ffffffff81815637>] ? _raw_spin_unlock_irq+0x27/0x50
> [  202.634945]  [<ffffffff8107e4fa>] warn_slowpath_fmt+0x4a/0x50
> [  202.634946]  [<ffffffff810d6d83>] trace_hardirqs_on_caller+0x113/0x1b0
> [  202.634948]  [<ffffffff810d6e2d>] trace_hardirqs_on+0xd/0x10
> [  202.634949]  [<ffffffff81815637>] _raw_spin_unlock_irq+0x27/0x50
> [  202.634951]  [<ffffffff81672042>] rtc_handler+0x32/0xa0
> [  202.634954]  [<ffffffff814c08a3>] acpi_ev_fixed_event_detect+0xd4/0xfb
> [  202.634956]  [<ffffffff814c2ccb>] acpi_ev_sci_xrupt_handler+0xf/0x2d
> [  202.634957]  [<ffffffff814ab3ee>] acpi_irq+0x11/0x2c
> [  202.634960]  [<ffffffff810e5288>] __handle_irq_event_percpu+0x58/0x370
> [  202.634961]  [<ffffffff810e55be>] handle_irq_event_percpu+0x1e/0x50
> [  202.634962]  [<ffffffff810e5624>] handle_irq_event+0x34/0x60
> [  202.634963]  [<ffffffff810e8906>] handle_fasteoi_irq+0xa6/0x170
> [  202.634966]  [<ffffffff8101eef5>] handle_irq+0x15/0x20
> [  202.634967]  [<ffffffff8101e548>] do_IRQ+0x68/0x130
> [  202.634968]  [<ffffffff81816789>] common_interrupt+0x89/0x89
> [  202.634970]  <EOI>
> [  202.634970]  [<ffffffff81814c73>] ? mwait_idle+0x93/0x210
> [  202.634971]  [<ffffffff81814c6a>] ? mwait_idle+0x8a/0x210
> [  202.634972]  [<ffffffff81026b0a>] arch_cpu_idle+0xa/0x10
> [  202.634973]  [<ffffffff8181509e>] default_idle_call+0x1e/0x30
> [  202.634974]  [<ffffffff810cbf6c>] cpu_startup_entry+0x17c/0x1f0
> [  202.634976]  [<ffffffff8180ca87>] rest_init+0x127/0x130
> [  202.634978]  [<ffffffff81f77f08>] start_kernel+0x3f6/0x403
> [  202.634980]  [<ffffffff81f7728f>] x86_64_start_reservations+0x2a/0x2c
> [  202.634981]  [<ffffffff81f77404>] x86_64_start_kernel+0x173/0x186
> [  202.634982] ---[ end trace 293c99618fa08d34 ]---
>=20
> Cc: Gabriele Mazzotta <gabriele.mzt@gmail.com>
> Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com>
> Fixes: 983bf1256edb ("rtc: cmos: Clear ACPI-driven alarms upon resume")
> Signed-off-by: Ville Syrj=C3=A4l=C3=A4 <ville.syrjala@linux.intel.com>
> ---
>  drivers/rtc/rtc-cmos.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
>=20
> diff --git a/drivers/rtc/rtc-cmos.c b/drivers/rtc/rtc-cmos.c
> index dd3d59806ffa..19cd49ad92dc 100644
> --- a/drivers/rtc/rtc-cmos.c
> +++ b/drivers/rtc/rtc-cmos.c
> @@ -996,8 +996,9 @@ static u32 rtc_handler(void *context)
>  	struct cmos_rtc *cmos =3D dev_get_drvdata(dev);
>  	unsigned char rtc_control =3D 0;
>  	unsigned char rtc_intr;
> +	unsigned long flags;
> =20
> -	spin_lock_irq(&rtc_lock);
> +	spin_lock_irqsave(&rtc_lock, flags);

My reading of the acpi fixed event handlers suggests that this can only
be called from interrupt context.

Anyway using irqsave is correct (just may be optimised away to a plain
spin_lock() if the condition that this is only called in irq context is
satisfied).

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
-Chris

--=20
Chris Wilson, Intel Open Source Technology Centre

--=20
You received this message because you are subscribed to "rtc-linux".
Membership options at http://groups.google.com/group/rtc-linux .
Please read http://groups.google.com/group/rtc-linux/web/checklist
before submitting a driver.
---=20
You received this message because you are subscribed to the Google Groups "=
rtc-linux" group.
To unsubscribe from this group and stop receiving emails from it, send an e=
mail to rtc-linux+unsubscribe@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.

^ permalink raw reply	[flat|nested] 12+ messages in thread
* Re: [PATCH] rtc: cmos: Don't enable interrupts in the middle of the interrupt handler
@ 2016-10-19 18:16   ` Chris Wilson
  0 siblings, 0 replies; 12+ messages in thread
From: Chris Wilson @ 2016-10-19 18:16 UTC (permalink / raw)
  To: ville.syrjala
  Cc: intel-gfx, Gabriele Mazzotta, Alexandre Belloni, linux-kernel, rtc-linux

On Wed, Oct 19, 2016 at 09:02:04PM +0300, ville.syrjala@linux.intel.com wrote:
> From: Ville Syrjälä <ville.syrjala@linux.intel.com>
> 
> Using spin_lock_irq()/spin_unlock_irq() from within the interrupt
> handler is a no-no. Let's save/restore the flags to avoid turning on
> interrupts prematurely.
> 
> We hit this in a bunch of our CI systems, but for whatever reason I
> wasn't able to reproduce on my own machine, so this fix is just
> based on the backtrace.
> 
> [  202.634918] WARNING: CPU: 0 PID: 0 at kernel/locking/lockdep.c:2729 trace_hardirqs_on_caller+0x113/0x1b0
> [  202.634919] DEBUG_LOCKS_WARN_ON(current->hardirq_context)
> [  202.634929] Modules linked in: snd_hda_intel i915 x86_pkg_temp_thermal intel_powerclamp coretemp crct10dif_pclmul crc32_pclmul ghash_clmulni_intel lpc_ich snd_hda_codec_realtek snd_hda_codec_generic snd_hda_codec_hdmi snd_hda_codec snd_hwdep i2c_designware_platform i2c_designware_core snd_hda_core mei_me mei snd_pcm r8169 mii sdhci_acpi sdhci mmc_core i2c_hid [last unloaded: i915]
> [  202.634930] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G     U          4.9.0-rc1-CI-CI_DRM_1734+ #1
> [  202.634931] Hardware name: GIGABYTE M4HM87P-00/M4HM87P-00, BIOS F6 12/10/2014
> [  202.634933]  ffff88011ea03d68 ffffffff8142dce5 ffff88011ea03db8 0000000000000000
> [  202.634934]  ffff88011ea03da8 ffffffff8107e496 00000aa900000002 ffffffff81e249a0
> [  202.634935]  ffffffff81815637 ffffffff82e7c280 0000000000000000 0000000000000004
> [  202.634936] Call Trace:
> [  202.634939]  <IRQ>
> [  202.634939]  [<ffffffff8142dce5>] dump_stack+0x67/0x92
> [  202.634941]  [<ffffffff8107e496>] __warn+0xc6/0xe0
> [  202.634944]  [<ffffffff81815637>] ? _raw_spin_unlock_irq+0x27/0x50
> [  202.634945]  [<ffffffff8107e4fa>] warn_slowpath_fmt+0x4a/0x50
> [  202.634946]  [<ffffffff810d6d83>] trace_hardirqs_on_caller+0x113/0x1b0
> [  202.634948]  [<ffffffff810d6e2d>] trace_hardirqs_on+0xd/0x10
> [  202.634949]  [<ffffffff81815637>] _raw_spin_unlock_irq+0x27/0x50
> [  202.634951]  [<ffffffff81672042>] rtc_handler+0x32/0xa0
> [  202.634954]  [<ffffffff814c08a3>] acpi_ev_fixed_event_detect+0xd4/0xfb
> [  202.634956]  [<ffffffff814c2ccb>] acpi_ev_sci_xrupt_handler+0xf/0x2d
> [  202.634957]  [<ffffffff814ab3ee>] acpi_irq+0x11/0x2c
> [  202.634960]  [<ffffffff810e5288>] __handle_irq_event_percpu+0x58/0x370
> [  202.634961]  [<ffffffff810e55be>] handle_irq_event_percpu+0x1e/0x50
> [  202.634962]  [<ffffffff810e5624>] handle_irq_event+0x34/0x60
> [  202.634963]  [<ffffffff810e8906>] handle_fasteoi_irq+0xa6/0x170
> [  202.634966]  [<ffffffff8101eef5>] handle_irq+0x15/0x20
> [  202.634967]  [<ffffffff8101e548>] do_IRQ+0x68/0x130
> [  202.634968]  [<ffffffff81816789>] common_interrupt+0x89/0x89
> [  202.634970]  <EOI>
> [  202.634970]  [<ffffffff81814c73>] ? mwait_idle+0x93/0x210
> [  202.634971]  [<ffffffff81814c6a>] ? mwait_idle+0x8a/0x210
> [  202.634972]  [<ffffffff81026b0a>] arch_cpu_idle+0xa/0x10
> [  202.634973]  [<ffffffff8181509e>] default_idle_call+0x1e/0x30
> [  202.634974]  [<ffffffff810cbf6c>] cpu_startup_entry+0x17c/0x1f0
> [  202.634976]  [<ffffffff8180ca87>] rest_init+0x127/0x130
> [  202.634978]  [<ffffffff81f77f08>] start_kernel+0x3f6/0x403
> [  202.634980]  [<ffffffff81f7728f>] x86_64_start_reservations+0x2a/0x2c
> [  202.634981]  [<ffffffff81f77404>] x86_64_start_kernel+0x173/0x186
> [  202.634982] ---[ end trace 293c99618fa08d34 ]---
> 
> Cc: Gabriele Mazzotta <gabriele.mzt@gmail.com>
> Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com>
> Fixes: 983bf1256edb ("rtc: cmos: Clear ACPI-driven alarms upon resume")
> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
> ---
>  drivers/rtc/rtc-cmos.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/rtc/rtc-cmos.c b/drivers/rtc/rtc-cmos.c
> index dd3d59806ffa..19cd49ad92dc 100644
> --- a/drivers/rtc/rtc-cmos.c
> +++ b/drivers/rtc/rtc-cmos.c
> @@ -996,8 +996,9 @@ static u32 rtc_handler(void *context)
>  	struct cmos_rtc *cmos = dev_get_drvdata(dev);
>  	unsigned char rtc_control = 0;
>  	unsigned char rtc_intr;
> +	unsigned long flags;
>  
> -	spin_lock_irq(&rtc_lock);
> +	spin_lock_irqsave(&rtc_lock, flags);

My reading of the acpi fixed event handlers suggests that this can only
be called from interrupt context.

Anyway using irqsave is correct (just may be optimised away to a plain
spin_lock() if the condition that this is only called in irq context is
satisfied).

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

^ permalink raw reply	[flat|nested] 12+ messages in thread
* Re: [Intel-gfx] [PATCH] rtc: cmos: Don't enable interrupts in the middle of the interrupt handler
  2016-10-19 18:16   ` [rtc-linux] Re: [Intel-gfx] " Chris Wilson
  (?)
@ 2016-10-19 18:33     ` Ville Syrjälä
  -1 siblings, 0 replies; 12+ messages in thread
From: Ville Syrjälä @ 2016-10-19 18:33 UTC (permalink / raw)
  To: Chris Wilson, rtc-linux, intel-gfx, Gabriele Mazzotta,
	Alexandre Belloni, linux-kernel

On Wed, Oct 19, 2016 at 07:16:39PM +0100, Chris Wilson wrote:
> On Wed, Oct 19, 2016 at 09:02:04PM +0300, ville.syrjala@linux.intel.com wrote:
> > From: Ville Syrjälä <ville.syrjala@linux.intel.com>
> > 
> > Using spin_lock_irq()/spin_unlock_irq() from within the interrupt
> > handler is a no-no. Let's save/restore the flags to avoid turning on
> > interrupts prematurely.
> > 
> > We hit this in a bunch of our CI systems, but for whatever reason I
> > wasn't able to reproduce on my own machine, so this fix is just
> > based on the backtrace.
> > 
> > [  202.634918] WARNING: CPU: 0 PID: 0 at kernel/locking/lockdep.c:2729 trace_hardirqs_on_caller+0x113/0x1b0
> > [  202.634919] DEBUG_LOCKS_WARN_ON(current->hardirq_context)
> > [  202.634929] Modules linked in: snd_hda_intel i915 x86_pkg_temp_thermal intel_powerclamp coretemp crct10dif_pclmul crc32_pclmul ghash_clmulni_intel lpc_ich snd_hda_codec_realtek snd_hda_codec_generic snd_hda_codec_hdmi snd_hda_codec snd_hwdep i2c_designware_platform i2c_designware_core snd_hda_core mei_me mei snd_pcm r8169 mii sdhci_acpi sdhci mmc_core i2c_hid [last unloaded: i915]
> > [  202.634930] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G     U          4.9.0-rc1-CI-CI_DRM_1734+ #1
> > [  202.634931] Hardware name: GIGABYTE M4HM87P-00/M4HM87P-00, BIOS F6 12/10/2014
> > [  202.634933]  ffff88011ea03d68 ffffffff8142dce5 ffff88011ea03db8 0000000000000000
> > [  202.634934]  ffff88011ea03da8 ffffffff8107e496 00000aa900000002 ffffffff81e249a0
> > [  202.634935]  ffffffff81815637 ffffffff82e7c280 0000000000000000 0000000000000004
> > [  202.634936] Call Trace:
> > [  202.634939]  <IRQ>
> > [  202.634939]  [<ffffffff8142dce5>] dump_stack+0x67/0x92
> > [  202.634941]  [<ffffffff8107e496>] __warn+0xc6/0xe0
> > [  202.634944]  [<ffffffff81815637>] ? _raw_spin_unlock_irq+0x27/0x50
> > [  202.634945]  [<ffffffff8107e4fa>] warn_slowpath_fmt+0x4a/0x50
> > [  202.634946]  [<ffffffff810d6d83>] trace_hardirqs_on_caller+0x113/0x1b0
> > [  202.634948]  [<ffffffff810d6e2d>] trace_hardirqs_on+0xd/0x10
> > [  202.634949]  [<ffffffff81815637>] _raw_spin_unlock_irq+0x27/0x50
> > [  202.634951]  [<ffffffff81672042>] rtc_handler+0x32/0xa0
> > [  202.634954]  [<ffffffff814c08a3>] acpi_ev_fixed_event_detect+0xd4/0xfb
> > [  202.634956]  [<ffffffff814c2ccb>] acpi_ev_sci_xrupt_handler+0xf/0x2d
> > [  202.634957]  [<ffffffff814ab3ee>] acpi_irq+0x11/0x2c
> > [  202.634960]  [<ffffffff810e5288>] __handle_irq_event_percpu+0x58/0x370
> > [  202.634961]  [<ffffffff810e55be>] handle_irq_event_percpu+0x1e/0x50
> > [  202.634962]  [<ffffffff810e5624>] handle_irq_event+0x34/0x60
> > [  202.634963]  [<ffffffff810e8906>] handle_fasteoi_irq+0xa6/0x170
> > [  202.634966]  [<ffffffff8101eef5>] handle_irq+0x15/0x20
> > [  202.634967]  [<ffffffff8101e548>] do_IRQ+0x68/0x130
> > [  202.634968]  [<ffffffff81816789>] common_interrupt+0x89/0x89
> > [  202.634970]  <EOI>
> > [  202.634970]  [<ffffffff81814c73>] ? mwait_idle+0x93/0x210
> > [  202.634971]  [<ffffffff81814c6a>] ? mwait_idle+0x8a/0x210
> > [  202.634972]  [<ffffffff81026b0a>] arch_cpu_idle+0xa/0x10
> > [  202.634973]  [<ffffffff8181509e>] default_idle_call+0x1e/0x30
> > [  202.634974]  [<ffffffff810cbf6c>] cpu_startup_entry+0x17c/0x1f0
> > [  202.634976]  [<ffffffff8180ca87>] rest_init+0x127/0x130
> > [  202.634978]  [<ffffffff81f77f08>] start_kernel+0x3f6/0x403
> > [  202.634980]  [<ffffffff81f7728f>] x86_64_start_reservations+0x2a/0x2c
> > [  202.634981]  [<ffffffff81f77404>] x86_64_start_kernel+0x173/0x186
> > [  202.634982] ---[ end trace 293c99618fa08d34 ]---
> > 
> > Cc: Gabriele Mazzotta <gabriele.mzt@gmail.com>
> > Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com>
> > Fixes: 983bf1256edb ("rtc: cmos: Clear ACPI-driven alarms upon resume")
> > Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
> > ---
> >  drivers/rtc/rtc-cmos.c | 5 +++--
> >  1 file changed, 3 insertions(+), 2 deletions(-)
> > 
> > diff --git a/drivers/rtc/rtc-cmos.c b/drivers/rtc/rtc-cmos.c
> > index dd3d59806ffa..19cd49ad92dc 100644
> > --- a/drivers/rtc/rtc-cmos.c
> > +++ b/drivers/rtc/rtc-cmos.c
> > @@ -996,8 +996,9 @@ static u32 rtc_handler(void *context)
> >  	struct cmos_rtc *cmos = dev_get_drvdata(dev);
> >  	unsigned char rtc_control = 0;
> >  	unsigned char rtc_intr;
> > +	unsigned long flags;
> >  
> > -	spin_lock_irq(&rtc_lock);
> > +	spin_lock_irqsave(&rtc_lock, flags);
> 
> My reading of the acpi fixed event handlers suggests that this can only
> be called from interrupt context.

Ah, could be. I didn't bother digging quite that deep.

> 
> Anyway using irqsave is correct (just may be optimised away to a plain
> spin_lock() if the condition that this is only called in irq context is
> satisfied).
> 
> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
> -Chris
> 
> -- 
> Chris Wilson, Intel Open Source Technology Centre

-- 
Ville Syrjälä
Intel OTC

^ permalink raw reply	[flat|nested] 12+ messages in thread
* [rtc-linux] Re: [Intel-gfx] [PATCH] rtc: cmos: Don't enable interrupts in the middle of the interrupt handler
@ 2016-10-19 18:33     ` Ville Syrjälä
  0 siblings, 0 replies; 12+ messages in thread
From: Ville Syrjälä @ 2016-10-19 18:33 UTC (permalink / raw)
  To: Chris Wilson, rtc-linux, intel-gfx, Gabriele Mazzotta,
	Alexandre Belloni, linux-kernel

On Wed, Oct 19, 2016 at 07:16:39PM +0100, Chris Wilson wrote:
> On Wed, Oct 19, 2016 at 09:02:04PM +0300, ville.syrjala@linux.intel.com w=
rote:
> > From: Ville Syrj=C3=A4l=C3=A4 <ville.syrjala@linux.intel.com>
> >=20
> > Using spin_lock_irq()/spin_unlock_irq() from within the interrupt
> > handler is a no-no. Let's save/restore the flags to avoid turning on
> > interrupts prematurely.
> >=20
> > We hit this in a bunch of our CI systems, but for whatever reason I
> > wasn't able to reproduce on my own machine, so this fix is just
> > based on the backtrace.
> >=20
> > [  202.634918] WARNING: CPU: 0 PID: 0 at kernel/locking/lockdep.c:2729 =
trace_hardirqs_on_caller+0x113/0x1b0
> > [  202.634919] DEBUG_LOCKS_WARN_ON(current->hardirq_context)
> > [  202.634929] Modules linked in: snd_hda_intel i915 x86_pkg_temp_therm=
al intel_powerclamp coretemp crct10dif_pclmul crc32_pclmul ghash_clmulni_in=
tel lpc_ich snd_hda_codec_realtek snd_hda_codec_generic snd_hda_codec_hdmi =
snd_hda_codec snd_hwdep i2c_designware_platform i2c_designware_core snd_hda=
_core mei_me mei snd_pcm r8169 mii sdhci_acpi sdhci mmc_core i2c_hid [last =
unloaded: i915]
> > [  202.634930] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G     U          =
4.9.0-rc1-CI-CI_DRM_1734+ #1
> > [  202.634931] Hardware name: GIGABYTE M4HM87P-00/M4HM87P-00, BIOS F6 1=
2/10/2014
> > [  202.634933]  ffff88011ea03d68 ffffffff8142dce5 ffff88011ea03db8 0000=
000000000000
> > [  202.634934]  ffff88011ea03da8 ffffffff8107e496 00000aa900000002 ffff=
ffff81e249a0
> > [  202.634935]  ffffffff81815637 ffffffff82e7c280 0000000000000000 0000=
000000000004
> > [  202.634936] Call Trace:
> > [  202.634939]  <IRQ>
> > [  202.634939]  [<ffffffff8142dce5>] dump_stack+0x67/0x92
> > [  202.634941]  [<ffffffff8107e496>] __warn+0xc6/0xe0
> > [  202.634944]  [<ffffffff81815637>] ? _raw_spin_unlock_irq+0x27/0x50
> > [  202.634945]  [<ffffffff8107e4fa>] warn_slowpath_fmt+0x4a/0x50
> > [  202.634946]  [<ffffffff810d6d83>] trace_hardirqs_on_caller+0x113/0x1=
b0
> > [  202.634948]  [<ffffffff810d6e2d>] trace_hardirqs_on+0xd/0x10
> > [  202.634949]  [<ffffffff81815637>] _raw_spin_unlock_irq+0x27/0x50
> > [  202.634951]  [<ffffffff81672042>] rtc_handler+0x32/0xa0
> > [  202.634954]  [<ffffffff814c08a3>] acpi_ev_fixed_event_detect+0xd4/0x=
fb
> > [  202.634956]  [<ffffffff814c2ccb>] acpi_ev_sci_xrupt_handler+0xf/0x2d
> > [  202.634957]  [<ffffffff814ab3ee>] acpi_irq+0x11/0x2c
> > [  202.634960]  [<ffffffff810e5288>] __handle_irq_event_percpu+0x58/0x3=
70
> > [  202.634961]  [<ffffffff810e55be>] handle_irq_event_percpu+0x1e/0x50
> > [  202.634962]  [<ffffffff810e5624>] handle_irq_event+0x34/0x60
> > [  202.634963]  [<ffffffff810e8906>] handle_fasteoi_irq+0xa6/0x170
> > [  202.634966]  [<ffffffff8101eef5>] handle_irq+0x15/0x20
> > [  202.634967]  [<ffffffff8101e548>] do_IRQ+0x68/0x130
> > [  202.634968]  [<ffffffff81816789>] common_interrupt+0x89/0x89
> > [  202.634970]  <EOI>
> > [  202.634970]  [<ffffffff81814c73>] ? mwait_idle+0x93/0x210
> > [  202.634971]  [<ffffffff81814c6a>] ? mwait_idle+0x8a/0x210
> > [  202.634972]  [<ffffffff81026b0a>] arch_cpu_idle+0xa/0x10
> > [  202.634973]  [<ffffffff8181509e>] default_idle_call+0x1e/0x30
> > [  202.634974]  [<ffffffff810cbf6c>] cpu_startup_entry+0x17c/0x1f0
> > [  202.634976]  [<ffffffff8180ca87>] rest_init+0x127/0x130
> > [  202.634978]  [<ffffffff81f77f08>] start_kernel+0x3f6/0x403
> > [  202.634980]  [<ffffffff81f7728f>] x86_64_start_reservations+0x2a/0x2=
c
> > [  202.634981]  [<ffffffff81f77404>] x86_64_start_kernel+0x173/0x186
> > [  202.634982] ---[ end trace 293c99618fa08d34 ]---
> >=20
> > Cc: Gabriele Mazzotta <gabriele.mzt@gmail.com>
> > Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com>
> > Fixes: 983bf1256edb ("rtc: cmos: Clear ACPI-driven alarms upon resume")
> > Signed-off-by: Ville Syrj=C3=A4l=C3=A4 <ville.syrjala@linux.intel.com>
> > ---
> >  drivers/rtc/rtc-cmos.c | 5 +++--
> >  1 file changed, 3 insertions(+), 2 deletions(-)
> >=20
> > diff --git a/drivers/rtc/rtc-cmos.c b/drivers/rtc/rtc-cmos.c
> > index dd3d59806ffa..19cd49ad92dc 100644
> > --- a/drivers/rtc/rtc-cmos.c
> > +++ b/drivers/rtc/rtc-cmos.c
> > @@ -996,8 +996,9 @@ static u32 rtc_handler(void *context)
> >  	struct cmos_rtc *cmos =3D dev_get_drvdata(dev);
> >  	unsigned char rtc_control =3D 0;
> >  	unsigned char rtc_intr;
> > +	unsigned long flags;
> > =20
> > -	spin_lock_irq(&rtc_lock);
> > +	spin_lock_irqsave(&rtc_lock, flags);
>=20
> My reading of the acpi fixed event handlers suggests that this can only
> be called from interrupt context.

Ah, could be. I didn't bother digging quite that deep.

>=20
> Anyway using irqsave is correct (just may be optimised away to a plain
> spin_lock() if the condition that this is only called in irq context is
> satisfied).
>=20
> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
> -Chris
>=20
> --=20
> Chris Wilson, Intel Open Source Technology Centre

--=20
Ville Syrj=C3=A4l=C3=A4
Intel OTC

--=20
You received this message because you are subscribed to "rtc-linux".
Membership options at http://groups.google.com/group/rtc-linux .
Please read http://groups.google.com/group/rtc-linux/web/checklist
before submitting a driver.
---=20
You received this message because you are subscribed to the Google Groups "=
rtc-linux" group.
To unsubscribe from this group and stop receiving emails from it, send an e=
mail to rtc-linux+unsubscribe@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.

^ permalink raw reply	[flat|nested] 12+ messages in thread
* Re: [Intel-gfx] [PATCH] rtc: cmos: Don't enable interrupts in the middle of the interrupt handler
@ 2016-10-19 18:33     ` Ville Syrjälä
  0 siblings, 0 replies; 12+ messages in thread
From: Ville Syrjälä @ 2016-10-19 18:33 UTC (permalink / raw)
  To: Chris Wilson, rtc-linux-/JYPxA39Uh5TLH3MbocFFw,
	intel-gfx-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW, Gabriele Mazzotta,
	Alexandre Belloni, linux-kernel-u79uwXL29TY76Z2rM5mHXA

On Wed, Oct 19, 2016 at 07:16:39PM +0100, Chris Wilson wrote:
> On Wed, Oct 19, 2016 at 09:02:04PM +0300, ville.syrjala-VuQAYsv1563Yd54FQh9/CA@public.gmane.org wrote:
> > From: Ville Syrjälä <ville.syrjala-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
> > 
> > Using spin_lock_irq()/spin_unlock_irq() from within the interrupt
> > handler is a no-no. Let's save/restore the flags to avoid turning on
> > interrupts prematurely.
> > 
> > We hit this in a bunch of our CI systems, but for whatever reason I
> > wasn't able to reproduce on my own machine, so this fix is just
> > based on the backtrace.
> > 
> > [  202.634918] WARNING: CPU: 0 PID: 0 at kernel/locking/lockdep.c:2729 trace_hardirqs_on_caller+0x113/0x1b0
> > [  202.634919] DEBUG_LOCKS_WARN_ON(current->hardirq_context)
> > [  202.634929] Modules linked in: snd_hda_intel i915 x86_pkg_temp_thermal intel_powerclamp coretemp crct10dif_pclmul crc32_pclmul ghash_clmulni_intel lpc_ich snd_hda_codec_realtek snd_hda_codec_generic snd_hda_codec_hdmi snd_hda_codec snd_hwdep i2c_designware_platform i2c_designware_core snd_hda_core mei_me mei snd_pcm r8169 mii sdhci_acpi sdhci mmc_core i2c_hid [last unloaded: i915]
> > [  202.634930] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G     U          4.9.0-rc1-CI-CI_DRM_1734+ #1
> > [  202.634931] Hardware name: GIGABYTE M4HM87P-00/M4HM87P-00, BIOS F6 12/10/2014
> > [  202.634933]  ffff88011ea03d68 ffffffff8142dce5 ffff88011ea03db8 0000000000000000
> > [  202.634934]  ffff88011ea03da8 ffffffff8107e496 00000aa900000002 ffffffff81e249a0
> > [  202.634935]  ffffffff81815637 ffffffff82e7c280 0000000000000000 0000000000000004
> > [  202.634936] Call Trace:
> > [  202.634939]  <IRQ>
> > [  202.634939]  [<ffffffff8142dce5>] dump_stack+0x67/0x92
> > [  202.634941]  [<ffffffff8107e496>] __warn+0xc6/0xe0
> > [  202.634944]  [<ffffffff81815637>] ? _raw_spin_unlock_irq+0x27/0x50
> > [  202.634945]  [<ffffffff8107e4fa>] warn_slowpath_fmt+0x4a/0x50
> > [  202.634946]  [<ffffffff810d6d83>] trace_hardirqs_on_caller+0x113/0x1b0
> > [  202.634948]  [<ffffffff810d6e2d>] trace_hardirqs_on+0xd/0x10
> > [  202.634949]  [<ffffffff81815637>] _raw_spin_unlock_irq+0x27/0x50
> > [  202.634951]  [<ffffffff81672042>] rtc_handler+0x32/0xa0
> > [  202.634954]  [<ffffffff814c08a3>] acpi_ev_fixed_event_detect+0xd4/0xfb
> > [  202.634956]  [<ffffffff814c2ccb>] acpi_ev_sci_xrupt_handler+0xf/0x2d
> > [  202.634957]  [<ffffffff814ab3ee>] acpi_irq+0x11/0x2c
> > [  202.634960]  [<ffffffff810e5288>] __handle_irq_event_percpu+0x58/0x370
> > [  202.634961]  [<ffffffff810e55be>] handle_irq_event_percpu+0x1e/0x50
> > [  202.634962]  [<ffffffff810e5624>] handle_irq_event+0x34/0x60
> > [  202.634963]  [<ffffffff810e8906>] handle_fasteoi_irq+0xa6/0x170
> > [  202.634966]  [<ffffffff8101eef5>] handle_irq+0x15/0x20
> > [  202.634967]  [<ffffffff8101e548>] do_IRQ+0x68/0x130
> > [  202.634968]  [<ffffffff81816789>] common_interrupt+0x89/0x89
> > [  202.634970]  <EOI>
> > [  202.634970]  [<ffffffff81814c73>] ? mwait_idle+0x93/0x210
> > [  202.634971]  [<ffffffff81814c6a>] ? mwait_idle+0x8a/0x210
> > [  202.634972]  [<ffffffff81026b0a>] arch_cpu_idle+0xa/0x10
> > [  202.634973]  [<ffffffff8181509e>] default_idle_call+0x1e/0x30
> > [  202.634974]  [<ffffffff810cbf6c>] cpu_startup_entry+0x17c/0x1f0
> > [  202.634976]  [<ffffffff8180ca87>] rest_init+0x127/0x130
> > [  202.634978]  [<ffffffff81f77f08>] start_kernel+0x3f6/0x403
> > [  202.634980]  [<ffffffff81f7728f>] x86_64_start_reservations+0x2a/0x2c
> > [  202.634981]  [<ffffffff81f77404>] x86_64_start_kernel+0x173/0x186
> > [  202.634982] ---[ end trace 293c99618fa08d34 ]---
> > 
> > Cc: Gabriele Mazzotta <gabriele.mzt-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
> > Cc: Alexandre Belloni <alexandre.belloni-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org>
> > Fixes: 983bf1256edb ("rtc: cmos: Clear ACPI-driven alarms upon resume")
> > Signed-off-by: Ville Syrjälä <ville.syrjala-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
> > ---
> >  drivers/rtc/rtc-cmos.c | 5 +++--
> >  1 file changed, 3 insertions(+), 2 deletions(-)
> > 
> > diff --git a/drivers/rtc/rtc-cmos.c b/drivers/rtc/rtc-cmos.c
> > index dd3d59806ffa..19cd49ad92dc 100644
> > --- a/drivers/rtc/rtc-cmos.c
> > +++ b/drivers/rtc/rtc-cmos.c
> > @@ -996,8 +996,9 @@ static u32 rtc_handler(void *context)
> >  	struct cmos_rtc *cmos = dev_get_drvdata(dev);
> >  	unsigned char rtc_control = 0;
> >  	unsigned char rtc_intr;
> > +	unsigned long flags;
> >  
> > -	spin_lock_irq(&rtc_lock);
> > +	spin_lock_irqsave(&rtc_lock, flags);
> 
> My reading of the acpi fixed event handlers suggests that this can only
> be called from interrupt context.

Ah, could be. I didn't bother digging quite that deep.

> 
> Anyway using irqsave is correct (just may be optimised away to a plain
> spin_lock() if the condition that this is only called in irq context is
> satisfied).
> 
> Reviewed-by: Chris Wilson <chris-Y6uKTt2uX1cEflXRtASbqLVCufUGDwFn@public.gmane.org>
> -Chris
> 
> -- 
> Chris Wilson, Intel Open Source Technology Centre

-- 
Ville Syrjälä
Intel OTC

-- 
You received this message because you are subscribed to "rtc-linux".
Membership options at http://groups.google.com/group/rtc-linux .
Please read http://groups.google.com/group/rtc-linux/web/checklist
before submitting a driver.
--- 
You received this message because you are subscribed to the Google Groups "rtc-linux" group.
To unsubscribe from this group and stop receiving emails from it, send an email to rtc-linux+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org
For more options, visit https://groups.google.com/d/optout.

^ permalink raw reply	[flat|nested] 12+ messages in thread
* Re: [PATCH] rtc: cmos: Don't enable interrupts in the middle of the interrupt handler
  2016-10-19 18:02 ` [rtc-linux] " ville.syrjala
  (?)
@ 2016-10-20 15:40   ` Alexandre Belloni
  -1 siblings, 0 replies; 12+ messages in thread
From: Alexandre Belloni @ 2016-10-20 15:40 UTC (permalink / raw)
  To: ville.syrjala; +Cc: rtc-linux, linux-kernel, intel-gfx, Gabriele Mazzotta

On 19/10/2016 at 21:02:04 +0300, ville.syrjala@linux.intel.com wrote :
> From: Ville Syrjälä <ville.syrjala@linux.intel.com>
> 
> Using spin_lock_irq()/spin_unlock_irq() from within the interrupt
> handler is a no-no. Let's save/restore the flags to avoid turning on
> interrupts prematurely.
> 
> We hit this in a bunch of our CI systems, but for whatever reason I
> wasn't able to reproduce on my own machine, so this fix is just
> based on the backtrace.
> 
> [  202.634918] WARNING: CPU: 0 PID: 0 at kernel/locking/lockdep.c:2729 trace_hardirqs_on_caller+0x113/0x1b0
> [  202.634919] DEBUG_LOCKS_WARN_ON(current->hardirq_context)
> [  202.634929] Modules linked in: snd_hda_intel i915 x86_pkg_temp_thermal intel_powerclamp coretemp crct10dif_pclmul crc32_pclmul ghash_clmulni_intel lpc_ich snd_hda_codec_realtek snd_hda_codec_generic snd_hda_codec_hdmi snd_hda_codec snd_hwdep i2c_designware_platform i2c_designware_core snd_hda_core mei_me mei snd_pcm r8169 mii sdhci_acpi sdhci mmc_core i2c_hid [last unloaded: i915]
> [  202.634930] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G     U          4.9.0-rc1-CI-CI_DRM_1734+ #1
> [  202.634931] Hardware name: GIGABYTE M4HM87P-00/M4HM87P-00, BIOS F6 12/10/2014
> [  202.634933]  ffff88011ea03d68 ffffffff8142dce5 ffff88011ea03db8 0000000000000000
> [  202.634934]  ffff88011ea03da8 ffffffff8107e496 00000aa900000002 ffffffff81e249a0
> [  202.634935]  ffffffff81815637 ffffffff82e7c280 0000000000000000 0000000000000004
> [  202.634936] Call Trace:
> [  202.634939]  <IRQ>
> [  202.634939]  [<ffffffff8142dce5>] dump_stack+0x67/0x92
> [  202.634941]  [<ffffffff8107e496>] __warn+0xc6/0xe0
> [  202.634944]  [<ffffffff81815637>] ? _raw_spin_unlock_irq+0x27/0x50
> [  202.634945]  [<ffffffff8107e4fa>] warn_slowpath_fmt+0x4a/0x50
> [  202.634946]  [<ffffffff810d6d83>] trace_hardirqs_on_caller+0x113/0x1b0
> [  202.634948]  [<ffffffff810d6e2d>] trace_hardirqs_on+0xd/0x10
> [  202.634949]  [<ffffffff81815637>] _raw_spin_unlock_irq+0x27/0x50
> [  202.634951]  [<ffffffff81672042>] rtc_handler+0x32/0xa0
> [  202.634954]  [<ffffffff814c08a3>] acpi_ev_fixed_event_detect+0xd4/0xfb
> [  202.634956]  [<ffffffff814c2ccb>] acpi_ev_sci_xrupt_handler+0xf/0x2d
> [  202.634957]  [<ffffffff814ab3ee>] acpi_irq+0x11/0x2c
> [  202.634960]  [<ffffffff810e5288>] __handle_irq_event_percpu+0x58/0x370
> [  202.634961]  [<ffffffff810e55be>] handle_irq_event_percpu+0x1e/0x50
> [  202.634962]  [<ffffffff810e5624>] handle_irq_event+0x34/0x60
> [  202.634963]  [<ffffffff810e8906>] handle_fasteoi_irq+0xa6/0x170
> [  202.634966]  [<ffffffff8101eef5>] handle_irq+0x15/0x20
> [  202.634967]  [<ffffffff8101e548>] do_IRQ+0x68/0x130
> [  202.634968]  [<ffffffff81816789>] common_interrupt+0x89/0x89
> [  202.634970]  <EOI>
> [  202.634970]  [<ffffffff81814c73>] ? mwait_idle+0x93/0x210
> [  202.634971]  [<ffffffff81814c6a>] ? mwait_idle+0x8a/0x210
> [  202.634972]  [<ffffffff81026b0a>] arch_cpu_idle+0xa/0x10
> [  202.634973]  [<ffffffff8181509e>] default_idle_call+0x1e/0x30
> [  202.634974]  [<ffffffff810cbf6c>] cpu_startup_entry+0x17c/0x1f0
> [  202.634976]  [<ffffffff8180ca87>] rest_init+0x127/0x130
> [  202.634978]  [<ffffffff81f77f08>] start_kernel+0x3f6/0x403
> [  202.634980]  [<ffffffff81f7728f>] x86_64_start_reservations+0x2a/0x2c
> [  202.634981]  [<ffffffff81f77404>] x86_64_start_kernel+0x173/0x186
> [  202.634982] ---[ end trace 293c99618fa08d34 ]---
> 
> Cc: Gabriele Mazzotta <gabriele.mzt@gmail.com>
> Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com>
> Fixes: 983bf1256edb ("rtc: cmos: Clear ACPI-driven alarms upon resume")
> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
> ---
>  drivers/rtc/rtc-cmos.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
Applied, thanks.

-- 
Alexandre Belloni, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com

^ permalink raw reply	[flat|nested] 12+ messages in thread
* [rtc-linux] Re: [PATCH] rtc: cmos: Don't enable interrupts in the middle of the interrupt handler
@ 2016-10-20 15:40   ` Alexandre Belloni
  0 siblings, 0 replies; 12+ messages in thread
From: Alexandre Belloni @ 2016-10-20 15:40 UTC (permalink / raw)
  To: ville.syrjala; +Cc: rtc-linux, linux-kernel, intel-gfx, Gabriele Mazzotta

On 19/10/2016 at 21:02:04 +0300, ville.syrjala@linux.intel.com wrote :
> From: Ville Syrj=C3=A4l=C3=A4 <ville.syrjala@linux.intel.com>
>=20
> Using spin_lock_irq()/spin_unlock_irq() from within the interrupt
> handler is a no-no. Let's save/restore the flags to avoid turning on
> interrupts prematurely.
>=20
> We hit this in a bunch of our CI systems, but for whatever reason I
> wasn't able to reproduce on my own machine, so this fix is just
> based on the backtrace.
>=20
> [  202.634918] WARNING: CPU: 0 PID: 0 at kernel/locking/lockdep.c:2729 tr=
ace_hardirqs_on_caller+0x113/0x1b0
> [  202.634919] DEBUG_LOCKS_WARN_ON(current->hardirq_context)
> [  202.634929] Modules linked in: snd_hda_intel i915 x86_pkg_temp_thermal=
 intel_powerclamp coretemp crct10dif_pclmul crc32_pclmul ghash_clmulni_inte=
l lpc_ich snd_hda_codec_realtek snd_hda_codec_generic snd_hda_codec_hdmi sn=
d_hda_codec snd_hwdep i2c_designware_platform i2c_designware_core snd_hda_c=
ore mei_me mei snd_pcm r8169 mii sdhci_acpi sdhci mmc_core i2c_hid [last un=
loaded: i915]
> [  202.634930] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G     U          4.=
9.0-rc1-CI-CI_DRM_1734+ #1
> [  202.634931] Hardware name: GIGABYTE M4HM87P-00/M4HM87P-00, BIOS F6 12/=
10/2014
> [  202.634933]  ffff88011ea03d68 ffffffff8142dce5 ffff88011ea03db8 000000=
0000000000
> [  202.634934]  ffff88011ea03da8 ffffffff8107e496 00000aa900000002 ffffff=
ff81e249a0
> [  202.634935]  ffffffff81815637 ffffffff82e7c280 0000000000000000 000000=
0000000004
> [  202.634936] Call Trace:
> [  202.634939]  <IRQ>
> [  202.634939]  [<ffffffff8142dce5>] dump_stack+0x67/0x92
> [  202.634941]  [<ffffffff8107e496>] __warn+0xc6/0xe0
> [  202.634944]  [<ffffffff81815637>] ? _raw_spin_unlock_irq+0x27/0x50
> [  202.634945]  [<ffffffff8107e4fa>] warn_slowpath_fmt+0x4a/0x50
> [  202.634946]  [<ffffffff810d6d83>] trace_hardirqs_on_caller+0x113/0x1b0
> [  202.634948]  [<ffffffff810d6e2d>] trace_hardirqs_on+0xd/0x10
> [  202.634949]  [<ffffffff81815637>] _raw_spin_unlock_irq+0x27/0x50
> [  202.634951]  [<ffffffff81672042>] rtc_handler+0x32/0xa0
> [  202.634954]  [<ffffffff814c08a3>] acpi_ev_fixed_event_detect+0xd4/0xfb
> [  202.634956]  [<ffffffff814c2ccb>] acpi_ev_sci_xrupt_handler+0xf/0x2d
> [  202.634957]  [<ffffffff814ab3ee>] acpi_irq+0x11/0x2c
> [  202.634960]  [<ffffffff810e5288>] __handle_irq_event_percpu+0x58/0x370
> [  202.634961]  [<ffffffff810e55be>] handle_irq_event_percpu+0x1e/0x50
> [  202.634962]  [<ffffffff810e5624>] handle_irq_event+0x34/0x60
> [  202.634963]  [<ffffffff810e8906>] handle_fasteoi_irq+0xa6/0x170
> [  202.634966]  [<ffffffff8101eef5>] handle_irq+0x15/0x20
> [  202.634967]  [<ffffffff8101e548>] do_IRQ+0x68/0x130
> [  202.634968]  [<ffffffff81816789>] common_interrupt+0x89/0x89
> [  202.634970]  <EOI>
> [  202.634970]  [<ffffffff81814c73>] ? mwait_idle+0x93/0x210
> [  202.634971]  [<ffffffff81814c6a>] ? mwait_idle+0x8a/0x210
> [  202.634972]  [<ffffffff81026b0a>] arch_cpu_idle+0xa/0x10
> [  202.634973]  [<ffffffff8181509e>] default_idle_call+0x1e/0x30
> [  202.634974]  [<ffffffff810cbf6c>] cpu_startup_entry+0x17c/0x1f0
> [  202.634976]  [<ffffffff8180ca87>] rest_init+0x127/0x130
> [  202.634978]  [<ffffffff81f77f08>] start_kernel+0x3f6/0x403
> [  202.634980]  [<ffffffff81f7728f>] x86_64_start_reservations+0x2a/0x2c
> [  202.634981]  [<ffffffff81f77404>] x86_64_start_kernel+0x173/0x186
> [  202.634982] ---[ end trace 293c99618fa08d34 ]---
>=20
> Cc: Gabriele Mazzotta <gabriele.mzt@gmail.com>
> Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com>
> Fixes: 983bf1256edb ("rtc: cmos: Clear ACPI-driven alarms upon resume")
> Signed-off-by: Ville Syrj=C3=A4l=C3=A4 <ville.syrjala@linux.intel.com>
> ---
>  drivers/rtc/rtc-cmos.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
>=20
Applied, thanks.

--=20
Alexandre Belloni, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com

--=20
You received this message because you are subscribed to "rtc-linux".
Membership options at http://groups.google.com/group/rtc-linux .
Please read http://groups.google.com/group/rtc-linux/web/checklist
before submitting a driver.
---=20
You received this message because you are subscribed to the Google Groups "=
rtc-linux" group.
To unsubscribe from this group and stop receiving emails from it, send an e=
mail to rtc-linux+unsubscribe@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.

^ permalink raw reply	[flat|nested] 12+ messages in thread
* Re: [PATCH] rtc: cmos: Don't enable interrupts in the middle of the interrupt handler
@ 2016-10-20 15:40   ` Alexandre Belloni
  0 siblings, 0 replies; 12+ messages in thread
From: Alexandre Belloni @ 2016-10-20 15:40 UTC (permalink / raw)
  To: ville.syrjala-VuQAYsv1563Yd54FQh9/CA
  Cc: rtc-linux-/JYPxA39Uh5TLH3MbocFFw,
	linux-kernel-u79uwXL29TY76Z2rM5mHXA,
	intel-gfx-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW, Gabriele Mazzotta

On 19/10/2016 at 21:02:04 +0300, ville.syrjala-VuQAYsv1563Yd54FQh9/CA@public.gmane.org wrote :
> From: Ville Syrjälä <ville.syrjala-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
> 
> Using spin_lock_irq()/spin_unlock_irq() from within the interrupt
> handler is a no-no. Let's save/restore the flags to avoid turning on
> interrupts prematurely.
> 
> We hit this in a bunch of our CI systems, but for whatever reason I
> wasn't able to reproduce on my own machine, so this fix is just
> based on the backtrace.
> 
> [  202.634918] WARNING: CPU: 0 PID: 0 at kernel/locking/lockdep.c:2729 trace_hardirqs_on_caller+0x113/0x1b0
> [  202.634919] DEBUG_LOCKS_WARN_ON(current->hardirq_context)
> [  202.634929] Modules linked in: snd_hda_intel i915 x86_pkg_temp_thermal intel_powerclamp coretemp crct10dif_pclmul crc32_pclmul ghash_clmulni_intel lpc_ich snd_hda_codec_realtek snd_hda_codec_generic snd_hda_codec_hdmi snd_hda_codec snd_hwdep i2c_designware_platform i2c_designware_core snd_hda_core mei_me mei snd_pcm r8169 mii sdhci_acpi sdhci mmc_core i2c_hid [last unloaded: i915]
> [  202.634930] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G     U          4.9.0-rc1-CI-CI_DRM_1734+ #1
> [  202.634931] Hardware name: GIGABYTE M4HM87P-00/M4HM87P-00, BIOS F6 12/10/2014
> [  202.634933]  ffff88011ea03d68 ffffffff8142dce5 ffff88011ea03db8 0000000000000000
> [  202.634934]  ffff88011ea03da8 ffffffff8107e496 00000aa900000002 ffffffff81e249a0
> [  202.634935]  ffffffff81815637 ffffffff82e7c280 0000000000000000 0000000000000004
> [  202.634936] Call Trace:
> [  202.634939]  <IRQ>
> [  202.634939]  [<ffffffff8142dce5>] dump_stack+0x67/0x92
> [  202.634941]  [<ffffffff8107e496>] __warn+0xc6/0xe0
> [  202.634944]  [<ffffffff81815637>] ? _raw_spin_unlock_irq+0x27/0x50
> [  202.634945]  [<ffffffff8107e4fa>] warn_slowpath_fmt+0x4a/0x50
> [  202.634946]  [<ffffffff810d6d83>] trace_hardirqs_on_caller+0x113/0x1b0
> [  202.634948]  [<ffffffff810d6e2d>] trace_hardirqs_on+0xd/0x10
> [  202.634949]  [<ffffffff81815637>] _raw_spin_unlock_irq+0x27/0x50
> [  202.634951]  [<ffffffff81672042>] rtc_handler+0x32/0xa0
> [  202.634954]  [<ffffffff814c08a3>] acpi_ev_fixed_event_detect+0xd4/0xfb
> [  202.634956]  [<ffffffff814c2ccb>] acpi_ev_sci_xrupt_handler+0xf/0x2d
> [  202.634957]  [<ffffffff814ab3ee>] acpi_irq+0x11/0x2c
> [  202.634960]  [<ffffffff810e5288>] __handle_irq_event_percpu+0x58/0x370
> [  202.634961]  [<ffffffff810e55be>] handle_irq_event_percpu+0x1e/0x50
> [  202.634962]  [<ffffffff810e5624>] handle_irq_event+0x34/0x60
> [  202.634963]  [<ffffffff810e8906>] handle_fasteoi_irq+0xa6/0x170
> [  202.634966]  [<ffffffff8101eef5>] handle_irq+0x15/0x20
> [  202.634967]  [<ffffffff8101e548>] do_IRQ+0x68/0x130
> [  202.634968]  [<ffffffff81816789>] common_interrupt+0x89/0x89
> [  202.634970]  <EOI>
> [  202.634970]  [<ffffffff81814c73>] ? mwait_idle+0x93/0x210
> [  202.634971]  [<ffffffff81814c6a>] ? mwait_idle+0x8a/0x210
> [  202.634972]  [<ffffffff81026b0a>] arch_cpu_idle+0xa/0x10
> [  202.634973]  [<ffffffff8181509e>] default_idle_call+0x1e/0x30
> [  202.634974]  [<ffffffff810cbf6c>] cpu_startup_entry+0x17c/0x1f0
> [  202.634976]  [<ffffffff8180ca87>] rest_init+0x127/0x130
> [  202.634978]  [<ffffffff81f77f08>] start_kernel+0x3f6/0x403
> [  202.634980]  [<ffffffff81f7728f>] x86_64_start_reservations+0x2a/0x2c
> [  202.634981]  [<ffffffff81f77404>] x86_64_start_kernel+0x173/0x186
> [  202.634982] ---[ end trace 293c99618fa08d34 ]---
> 
> Cc: Gabriele Mazzotta <gabriele.mzt-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
> Cc: Alexandre Belloni <alexandre.belloni-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org>
> Fixes: 983bf1256edb ("rtc: cmos: Clear ACPI-driven alarms upon resume")
> Signed-off-by: Ville Syrjälä <ville.syrjala-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
> ---
>  drivers/rtc/rtc-cmos.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
Applied, thanks.

-- 
Alexandre Belloni, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com

-- 
You received this message because you are subscribed to "rtc-linux".
Membership options at http://groups.google.com/group/rtc-linux .
Please read http://groups.google.com/group/rtc-linux/web/checklist
before submitting a driver.
--- 
You received this message because you are subscribed to the Google Groups "rtc-linux" group.
To unsubscribe from this group and stop receiving emails from it, send an email to rtc-linux+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org
For more options, visit https://groups.google.com/d/optout.

^ permalink raw reply	[flat|nested] 12+ messages in thread
end of thread, other threads:[~2016-10-20 15:41 UTC | newest]

Thread overview: 12+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2016-10-19 18:02 [PATCH] rtc: cmos: Don't enable interrupts in the middle of the interrupt handler ville.syrjala
2016-10-19 18:02 ` ville.syrjala-VuQAYsv1563Yd54FQh9/CA
2016-10-19 18:02 ` [rtc-linux] " ville.syrjala
2016-10-19 18:16 ` [Intel-gfx] " Chris Wilson
2016-10-19 18:16   ` Chris Wilson
2016-10-19 18:16   ` [rtc-linux] Re: [Intel-gfx] " Chris Wilson
2016-10-19 18:33   ` Ville Syrjälä
2016-10-19 18:33     ` Ville Syrjälä
2016-10-19 18:33     ` [rtc-linux] " Ville Syrjälä
2016-10-20 15:40 ` Alexandre Belloni
2016-10-20 15:40   ` Alexandre Belloni
2016-10-20 15:40   ` [rtc-linux] " Alexandre Belloni

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.