* [PATCH 0/2] dmaengine: usb-dmac: Runtime PM Related Fixes
@ 2015-10-01 7:22 Geert Uytterhoeven
2015-10-01 7:22 ` [PATCH 1/2] dmaengine: usb-dmac: Fix crash on runtime suspend Geert Uytterhoeven
` (2 more replies)
0 siblings, 3 replies; 12+ messages in thread
From: Geert Uytterhoeven @ 2015-10-01 7:22 UTC (permalink / raw)
To: Vinod Koul, Yoshihiro Shimoda
Cc: Sergei Shtylyov, dmaengine, linux-sh, linux-pm,
Geert Uytterhoeven
Hi Vinod, Shimoda-san,
This series fixes a crash and an imbalance in the usb-dmac driver.
Geert Uytterhoeven (2):
dmaengine: usb-dmac: Fix crash on runtime suspend
dmaengine: usb-dmac: Fix pm_runtime_{enable,disable}() imbalance
drivers/dma/sh/usb-dmac.c | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)
--
1.9.1
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
^ permalink raw reply [flat|nested] 12+ messages in thread
* [PATCH 1/2] dmaengine: usb-dmac: Fix crash on runtime suspend
2015-10-01 7:22 [PATCH 0/2] dmaengine: usb-dmac: Runtime PM Related Fixes Geert Uytterhoeven
@ 2015-10-01 7:22 ` Geert Uytterhoeven
2015-10-01 10:53 ` Yoshihiro Shimoda
2015-10-01 7:22 ` [PATCH 2/2] dmaengine: usb-dmac: Fix pm_runtime_{enable,disable}() imbalance Geert Uytterhoeven
2015-10-07 14:01 ` [PATCH 0/2] dmaengine: usb-dmac: Runtime PM Related Fixes Vinod Koul
2 siblings, 1 reply; 12+ messages in thread
From: Geert Uytterhoeven @ 2015-10-01 7:22 UTC (permalink / raw)
To: Vinod Koul, Yoshihiro Shimoda
Cc: Sergei Shtylyov, dmaengine, linux-sh, linux-pm,
Geert Uytterhoeven
If CONFIG_PREEMPT=y:
Unable to handle kernel NULL pointer dereference at virtual address 00000014
pgd = c0003000
[00000014] *pgd€000040004003, *pmd\0000000
Internal error: Oops: 206 [#1] PREEMPT SMP ARM
Modules linked in:
CPU: 0 PID: 17 Comm: kworker/0:1 Tainted: G W 4.3.0-rc3-koelsch-022
71-g705498fc5e6a5da8-dirty #1789
Hardware name: Generic R8A7791 (Flattened Device Tree)
Workqueue: pm pm_runtime_work
task: ef578e40 ti: ef57a000 task.ti: ef57a000
PC is at usb_dmac_chan_halt+0xc/0xc0
LR is at usb_dmac_runtime_suspend+0x28/0x38
pc : [<c023c880>] lr : [<c023c95c>] psr: 80000113
sp : ef57bdf8 ip : 00000008 fp : 00000003
r10: 00000008 r9 : c06ab928 r8 : ef49e810
r7 : 00000000 r6 : 000000ac r5 : ef770010 r4 : 00000000
r3 : 00000000 r2 : 8ffc2b84 r1 : 00000000 r0 : ef770010
Flags: Nzcv IRQs on FIQs on Mode SVC_32 ISA ARM Segment kernel
Control: 30c5307d Table: 40003000 DAC: fffffffd
Process kworker/0:1 (pid: 17, stack limit = 0xef57a210)
Stack: (0xef57bdf8 to 0xef57c000)
[...
[<c023c880>] (usb_dmac_chan_halt) from [<c023c95c>] (usb_dmac_runtime_suspend+0x28/0x38)
[<c023c95c>] (usb_dmac_runtime_suspend) from [<c027b25c>] (pm_genpd_runtime_suspend+0x74/0x23c)
This happens because usb_dmac_probe() calls pm_runtime_put() before
usb_dmac_chan_probe(), leading to the device being suspended before the
DMA channels are initialized, causing a NULL pointer dereference.
Move the call to pm_runtime_put() to the end of usb_dmac_probe() to fix
this.
Add a check to usb_dmac_runtime_suspend() to prevent the crash from
happening in the error path.
Reported-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
drivers/dma/sh/usb-dmac.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/drivers/dma/sh/usb-dmac.c b/drivers/dma/sh/usb-dmac.c
index ebd8a5f398b08ee2..f305738b5adf8cc9 100644
--- a/drivers/dma/sh/usb-dmac.c
+++ b/drivers/dma/sh/usb-dmac.c
@@ -679,8 +679,11 @@ static int usb_dmac_runtime_suspend(struct device *dev)
struct usb_dmac *dmac = dev_get_drvdata(dev);
int i;
- for (i = 0; i < dmac->n_channels; ++i)
+ for (i = 0; i < dmac->n_channels; ++i) {
+ if (!dmac->channels[i].iomem)
+ break;
usb_dmac_chan_halt(&dmac->channels[i]);
+ }
return 0;
}
@@ -803,7 +806,6 @@ static int usb_dmac_probe(struct platform_device *pdev)
}
ret = usb_dmac_init(dmac);
- pm_runtime_put(&pdev->dev);
if (ret) {
dev_err(&pdev->dev, "failed to reset device\n");
@@ -851,10 +853,12 @@ static int usb_dmac_probe(struct platform_device *pdev)
if (ret < 0)
goto error;
+ pm_runtime_put(&pdev->dev);
return 0;
error:
of_dma_controller_free(pdev->dev.of_node);
+ pm_runtime_put(&pdev->dev);
pm_runtime_disable(&pdev->dev);
return ret;
}
--
1.9.1
^ permalink raw reply related [flat|nested] 12+ messages in thread
* [PATCH 2/2] dmaengine: usb-dmac: Fix pm_runtime_{enable,disable}() imbalance
2015-10-01 7:22 [PATCH 0/2] dmaengine: usb-dmac: Runtime PM Related Fixes Geert Uytterhoeven
2015-10-01 7:22 ` [PATCH 1/2] dmaengine: usb-dmac: Fix crash on runtime suspend Geert Uytterhoeven
@ 2015-10-01 7:22 ` Geert Uytterhoeven
2015-10-07 14:01 ` [PATCH 0/2] dmaengine: usb-dmac: Runtime PM Related Fixes Vinod Koul
2 siblings, 0 replies; 12+ messages in thread
From: Geert Uytterhoeven @ 2015-10-01 7:22 UTC (permalink / raw)
To: Vinod Koul, Yoshihiro Shimoda
Cc: Sergei Shtylyov, dmaengine, linux-sh, linux-pm,
Geert Uytterhoeven
If the call to pm_runtime_get_sync() failed, Runtime PM was left
enabled.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
drivers/dma/sh/usb-dmac.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/dma/sh/usb-dmac.c b/drivers/dma/sh/usb-dmac.c
index f305738b5adf8cc9..f1bcc2a163b30cef 100644
--- a/drivers/dma/sh/usb-dmac.c
+++ b/drivers/dma/sh/usb-dmac.c
@@ -802,7 +802,7 @@ static int usb_dmac_probe(struct platform_device *pdev)
ret = pm_runtime_get_sync(&pdev->dev);
if (ret < 0) {
dev_err(&pdev->dev, "runtime PM get sync failed (%d)\n", ret);
- return ret;
+ goto error_pm;
}
ret = usb_dmac_init(dmac);
@@ -859,6 +859,7 @@ static int usb_dmac_probe(struct platform_device *pdev)
error:
of_dma_controller_free(pdev->dev.of_node);
pm_runtime_put(&pdev->dev);
+error_pm:
pm_runtime_disable(&pdev->dev);
return ret;
}
--
1.9.1
^ permalink raw reply related [flat|nested] 12+ messages in thread
* RE: [PATCH 1/2] dmaengine: usb-dmac: Fix crash on runtime suspend
2015-10-01 7:22 ` [PATCH 1/2] dmaengine: usb-dmac: Fix crash on runtime suspend Geert Uytterhoeven
@ 2015-10-01 10:53 ` Yoshihiro Shimoda
2015-10-01 12:26 ` Sergei Shtylyov
0 siblings, 1 reply; 12+ messages in thread
From: Yoshihiro Shimoda @ 2015-10-01 10:53 UTC (permalink / raw)
To: Geert Uytterhoeven, Vinod Koul
Cc: Sergei Shtylyov, dmaengine@vger.kernel.org,
linux-sh@vger.kernel.org, linux-pm@vger.kernel.org
Hi Geert-san,
> Sent: Thursday, October 01, 2015 4:22 PM
>
> If CONFIG_PREEMPT=y:
>
> Unable to handle kernel NULL pointer dereference at virtual address 00000014
> pgd = c0003000
> [00000014] *pgd€000040004003, *pmd\0000000
> Internal error: Oops: 206 [#1] PREEMPT SMP ARM
> Modules linked in:
> CPU: 0 PID: 17 Comm: kworker/0:1 Tainted: G W 4.3.0-rc3-koelsch-022
> 71-g705498fc5e6a5da8-dirty #1789
> Hardware name: Generic R8A7791 (Flattened Device Tree)
> Workqueue: pm pm_runtime_work
> task: ef578e40 ti: ef57a000 task.ti: ef57a000
> PC is at usb_dmac_chan_halt+0xc/0xc0
> LR is at usb_dmac_runtime_suspend+0x28/0x38
> pc : [<c023c880>] lr : [<c023c95c>] psr: 80000113
> sp : ef57bdf8 ip : 00000008 fp : 00000003
> r10: 00000008 r9 : c06ab928 r8 : ef49e810
> r7 : 00000000 r6 : 000000ac r5 : ef770010 r4 : 00000000
> r3 : 00000000 r2 : 8ffc2b84 r1 : 00000000 r0 : ef770010
> Flags: Nzcv IRQs on FIQs on Mode SVC_32 ISA ARM Segment kernel
> Control: 30c5307d Table: 40003000 DAC: fffffffd
> Process kworker/0:1 (pid: 17, stack limit = 0xef57a210)
> Stack: (0xef57bdf8 to 0xef57c000)
>
> [...
>
> [<c023c880>] (usb_dmac_chan_halt) from [<c023c95c>] (usb_dmac_runtime_suspend+0x28/0x38)
> [<c023c95c>] (usb_dmac_runtime_suspend) from [<c027b25c>] (pm_genpd_runtime_suspend+0x74/0x23c)
>
> This happens because usb_dmac_probe() calls pm_runtime_put() before
> usb_dmac_chan_probe(), leading to the device being suspended before the
> DMA channels are initialized, causing a NULL pointer dereference.
>
> Move the call to pm_runtime_put() to the end of usb_dmac_probe() to fix
> this.
>
> Add a check to usb_dmac_runtime_suspend() to prevent the crash from
> happening in the error path.
>
> Reported-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
I could not duplicate this issue completely on Lager.
Even if I enabled ealyprintk, I didn't see the panic log.
(Several kernel message appeared, and then the kernel hung.)
Anyway, I tested this patch that kernel could boot correctly even if CONFIG_PREEMPT=y.
So,
Tested-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Best regards,
Yoshihiro Shimoda
> ---
> drivers/dma/sh/usb-dmac.c | 8 ++++++--
> 1 file changed, 6 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/dma/sh/usb-dmac.c b/drivers/dma/sh/usb-dmac.c
> index ebd8a5f398b08ee2..f305738b5adf8cc9 100644
> --- a/drivers/dma/sh/usb-dmac.c
> +++ b/drivers/dma/sh/usb-dmac.c
> @@ -679,8 +679,11 @@ static int usb_dmac_runtime_suspend(struct device *dev)
> struct usb_dmac *dmac = dev_get_drvdata(dev);
> int i;
>
> - for (i = 0; i < dmac->n_channels; ++i)
> + for (i = 0; i < dmac->n_channels; ++i) {
> + if (!dmac->channels[i].iomem)
> + break;
> usb_dmac_chan_halt(&dmac->channels[i]);
> + }
>
> return 0;
> }
> @@ -803,7 +806,6 @@ static int usb_dmac_probe(struct platform_device *pdev)
> }
>
> ret = usb_dmac_init(dmac);
> - pm_runtime_put(&pdev->dev);
>
> if (ret) {
> dev_err(&pdev->dev, "failed to reset device\n");
> @@ -851,10 +853,12 @@ static int usb_dmac_probe(struct platform_device *pdev)
> if (ret < 0)
> goto error;
>
> + pm_runtime_put(&pdev->dev);
> return 0;
>
> error:
> of_dma_controller_free(pdev->dev.of_node);
> + pm_runtime_put(&pdev->dev);
> pm_runtime_disable(&pdev->dev);
> return ret;
> }
> --
> 1.9.1
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH 1/2] dmaengine: usb-dmac: Fix crash on runtime suspend
2015-10-01 10:53 ` Yoshihiro Shimoda
@ 2015-10-01 12:26 ` Sergei Shtylyov
2015-10-02 1:00 ` Yoshihiro Shimoda
0 siblings, 1 reply; 12+ messages in thread
From: Sergei Shtylyov @ 2015-10-01 12:26 UTC (permalink / raw)
To: Yoshihiro Shimoda, Geert Uytterhoeven, Vinod Koul
Cc: dmaengine@vger.kernel.org, linux-sh@vger.kernel.org,
linux-pm@vger.kernel.org
Hello.
On 10/1/2015 1:53 PM, Yoshihiro Shimoda wrote:
>> If CONFIG_PREEMPT=y:
Actually, it happens even with CONFIG_PREEMPT_VOLUNTARY=y.
>> Unable to handle kernel NULL pointer dereference at virtual address 00000014
>> pgd = c0003000
>> [00000014] *pgd€000040004003, *pmd\0000000
>> Internal error: Oops: 206 [#1] PREEMPT SMP ARM
>> Modules linked in:
>> CPU: 0 PID: 17 Comm: kworker/0:1 Tainted: G W 4.3.0-rc3-koelsch-022
>> 71-g705498fc5e6a5da8-dirty #1789
>> Hardware name: Generic R8A7791 (Flattened Device Tree)
>> Workqueue: pm pm_runtime_work
>> task: ef578e40 ti: ef57a000 task.ti: ef57a000
>> PC is at usb_dmac_chan_halt+0xc/0xc0
>> LR is at usb_dmac_runtime_suspend+0x28/0x38
>> pc : [<c023c880>] lr : [<c023c95c>] psr: 80000113
>> sp : ef57bdf8 ip : 00000008 fp : 00000003
>> r10: 00000008 r9 : c06ab928 r8 : ef49e810
>> r7 : 00000000 r6 : 000000ac r5 : ef770010 r4 : 00000000
>> r3 : 00000000 r2 : 8ffc2b84 r1 : 00000000 r0 : ef770010
>> Flags: Nzcv IRQs on FIQs on Mode SVC_32 ISA ARM Segment kernel
>> Control: 30c5307d Table: 40003000 DAC: fffffffd
>> Process kworker/0:1 (pid: 17, stack limit = 0xef57a210)
>> Stack: (0xef57bdf8 to 0xef57c000)
>>
>> [...
>>
>> [<c023c880>] (usb_dmac_chan_halt) from [<c023c95c>] (usb_dmac_runtime_suspend+0x28/0x38)
>> [<c023c95c>] (usb_dmac_runtime_suspend) from [<c027b25c>] (pm_genpd_runtime_suspend+0x74/0x23c)
>>
>> This happens because usb_dmac_probe() calls pm_runtime_put() before
>> usb_dmac_chan_probe(), leading to the device being suspended before the
>> DMA channels are initialized, causing a NULL pointer dereference.
>>
>> Move the call to pm_runtime_put() to the end of usb_dmac_probe() to fix
>> this.
>>
>> Add a check to usb_dmac_runtime_suspend() to prevent the crash from
>> happening in the error path.
>>
>> Reported-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
>> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
>
> I could not duplicate this issue completely on Lager.
> Even if I enabled ealyprintk, I didn't see the panic log.
> (Several kernel message appeared, and then the kernel hung.)
I guess you also need to specify console=. The device tree console
assignment (from the "stdout-path" prop) happens too late, the console gets
switched to /dev/tty0 first. I forgot to mention that the pseudo-console
(CONFIG_VT) should be disabled as well.
> Anyway, I tested this patch that kernel could boot correctly even if CONFIG_PREEMPT=y.
> So,
> Tested-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Thank you. :-)
> Best regards,
> Yoshihiro Shimoda
MBR, Sergei
^ permalink raw reply [flat|nested] 12+ messages in thread
* RE: [PATCH 1/2] dmaengine: usb-dmac: Fix crash on runtime suspend
2015-10-01 12:26 ` Sergei Shtylyov
@ 2015-10-02 1:00 ` Yoshihiro Shimoda
2015-10-02 10:54 ` Sergei Shtylyov
0 siblings, 1 reply; 12+ messages in thread
From: Yoshihiro Shimoda @ 2015-10-02 1:00 UTC (permalink / raw)
To: Sergei Shtylyov, Geert Uytterhoeven, Vinod Koul
Cc: dmaengine@vger.kernel.org, linux-sh@vger.kernel.org,
linux-pm@vger.kernel.org
Hi Sergei-san,
> Sent: Thursday, October 01, 2015 9:27 PM
>
> Hello.
>
> On 10/1/2015 1:53 PM, Yoshihiro Shimoda wrote:
>
> >> If CONFIG_PREEMPT=y:
>
> Actually, it happens even with CONFIG_PREEMPT_VOLUNTARY=y.
>
> >> Unable to handle kernel NULL pointer dereference at virtual address 00000014
> >> pgd = c0003000
> >> [00000014] *pgd€000040004003, *pmd\0000000
> >> Internal error: Oops: 206 [#1] PREEMPT SMP ARM
> >> Modules linked in:
> >> CPU: 0 PID: 17 Comm: kworker/0:1 Tainted: G W 4.3.0-rc3-koelsch-022
> >> 71-g705498fc5e6a5da8-dirty #1789
> >> Hardware name: Generic R8A7791 (Flattened Device Tree)
> >> Workqueue: pm pm_runtime_work
> >> task: ef578e40 ti: ef57a000 task.ti: ef57a000
> >> PC is at usb_dmac_chan_halt+0xc/0xc0
> >> LR is at usb_dmac_runtime_suspend+0x28/0x38
> >> pc : [<c023c880>] lr : [<c023c95c>] psr: 80000113
> >> sp : ef57bdf8 ip : 00000008 fp : 00000003
> >> r10: 00000008 r9 : c06ab928 r8 : ef49e810
> >> r7 : 00000000 r6 : 000000ac r5 : ef770010 r4 : 00000000
> >> r3 : 00000000 r2 : 8ffc2b84 r1 : 00000000 r0 : ef770010
> >> Flags: Nzcv IRQs on FIQs on Mode SVC_32 ISA ARM Segment kernel
> >> Control: 30c5307d Table: 40003000 DAC: fffffffd
> >> Process kworker/0:1 (pid: 17, stack limit = 0xef57a210)
> >> Stack: (0xef57bdf8 to 0xef57c000)
> >>
> >> [...
> >>
> >> [<c023c880>] (usb_dmac_chan_halt) from [<c023c95c>] (usb_dmac_runtime_suspend+0x28/0x38)
> >> [<c023c95c>] (usb_dmac_runtime_suspend) from [<c027b25c>] (pm_genpd_runtime_suspend+0x74/0x23c)
> >>
> >> This happens because usb_dmac_probe() calls pm_runtime_put() before
> >> usb_dmac_chan_probe(), leading to the device being suspended before the
> >> DMA channels are initialized, causing a NULL pointer dereference.
> >>
> >> Move the call to pm_runtime_put() to the end of usb_dmac_probe() to fix
> >> this.
> >>
> >> Add a check to usb_dmac_runtime_suspend() to prevent the crash from
> >> happening in the error path.
> >>
> >> Reported-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
> >> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> >
> > I could not duplicate this issue completely on Lager.
> > Even if I enabled ealyprintk, I didn't see the panic log.
> > (Several kernel message appeared, and then the kernel hung.)
>
> I guess you also need to specify console=. The device tree console
> assignment (from the "stdout-path" prop) happens too late, the console gets
> switched to /dev/tty0 first. I forgot to mention that the pseudo-console
> (CONFIG_VT) should be disabled as well.
Thank you for your comment!
I was able to look the panic log if I added specify console= in the bootargs.
(Even if CONFIG_VT=y, the log appeared.)
> > Anyway, I tested this patch that kernel could boot correctly even if CONFIG_PREEMPT=y.
> > So,
> > Tested-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
>
> Thank you. :-)
You're welcome! And, thank you for the report.
Best regards,
Yoshihiro Shimoda
> > Best regards,
> > Yoshihiro Shimoda
>
> MBR, Sergei
>
> --
> To unsubscribe from this list: send the line "unsubscribe dmaengine" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH 1/2] dmaengine: usb-dmac: Fix crash on runtime suspend
2015-10-02 1:00 ` Yoshihiro Shimoda
@ 2015-10-02 10:54 ` Sergei Shtylyov
0 siblings, 0 replies; 12+ messages in thread
From: Sergei Shtylyov @ 2015-10-02 10:54 UTC (permalink / raw)
To: Yoshihiro Shimoda, Geert Uytterhoeven, Vinod Koul
Cc: dmaengine@vger.kernel.org, linux-sh@vger.kernel.org,
linux-pm@vger.kernel.org
Hello.
On 10/2/2015 4:00 AM, Yoshihiro Shimoda wrote:
>>>> If CONFIG_PREEMPT=y:
>>
>> Actually, it happens even with CONFIG_PREEMPT_VOLUNTARY=y.
>>
>>>> Unable to handle kernel NULL pointer dereference at virtual address 00000014
>>>> pgd = c0003000
>>>> [00000014] *pgd€000040004003, *pmd\0000000
>>>> Internal error: Oops: 206 [#1] PREEMPT SMP ARM
>>>> Modules linked in:
>>>> CPU: 0 PID: 17 Comm: kworker/0:1 Tainted: G W 4.3.0-rc3-koelsch-022
>>>> 71-g705498fc5e6a5da8-dirty #1789
>>>> Hardware name: Generic R8A7791 (Flattened Device Tree)
>>>> Workqueue: pm pm_runtime_work
>>>> task: ef578e40 ti: ef57a000 task.ti: ef57a000
>>>> PC is at usb_dmac_chan_halt+0xc/0xc0
>>>> LR is at usb_dmac_runtime_suspend+0x28/0x38
>>>> pc : [<c023c880>] lr : [<c023c95c>] psr: 80000113
>>>> sp : ef57bdf8 ip : 00000008 fp : 00000003
>>>> r10: 00000008 r9 : c06ab928 r8 : ef49e810
>>>> r7 : 00000000 r6 : 000000ac r5 : ef770010 r4 : 00000000
>>>> r3 : 00000000 r2 : 8ffc2b84 r1 : 00000000 r0 : ef770010
>>>> Flags: Nzcv IRQs on FIQs on Mode SVC_32 ISA ARM Segment kernel
>>>> Control: 30c5307d Table: 40003000 DAC: fffffffd
>>>> Process kworker/0:1 (pid: 17, stack limit = 0xef57a210)
>>>> Stack: (0xef57bdf8 to 0xef57c000)
>>>>
>>>> [...
>>>>
>>>> [<c023c880>] (usb_dmac_chan_halt) from [<c023c95c>] (usb_dmac_runtime_suspend+0x28/0x38)
>>>> [<c023c95c>] (usb_dmac_runtime_suspend) from [<c027b25c>] (pm_genpd_runtime_suspend+0x74/0x23c)
>>>>
>>>> This happens because usb_dmac_probe() calls pm_runtime_put() before
>>>> usb_dmac_chan_probe(), leading to the device being suspended before the
>>>> DMA channels are initialized, causing a NULL pointer dereference.
>>>>
>>>> Move the call to pm_runtime_put() to the end of usb_dmac_probe() to fix
>>>> this.
>>>>
>>>> Add a check to usb_dmac_runtime_suspend() to prevent the crash from
>>>> happening in the error path.
>>>>
>>>> Reported-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
>>>> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
>>>
>>> I could not duplicate this issue completely on Lager.
>>> Even if I enabled ealyprintk, I didn't see the panic log.
>>> (Several kernel message appeared, and then the kernel hung.)
>>
>> I guess you also need to specify console=. The device tree console
>> assignment (from the "stdout-path" prop) happens too late, the console gets
>> switched to /dev/tty0 first. I forgot to mention that the pseudo-console
>> (CONFIG_VT) should be disabled as well.
>
> Thank you for your comment!
> I was able to look the panic log if I added specify console= in the bootargs.
> (Even if CONFIG_VT=y, the log appeared.)
Yeah, I got things somewhat mixed up, specifying console= alone should help.
MBR, Sergei
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH 0/2] dmaengine: usb-dmac: Runtime PM Related Fixes
2015-10-01 7:22 [PATCH 0/2] dmaengine: usb-dmac: Runtime PM Related Fixes Geert Uytterhoeven
2015-10-01 7:22 ` [PATCH 1/2] dmaengine: usb-dmac: Fix crash on runtime suspend Geert Uytterhoeven
2015-10-01 7:22 ` [PATCH 2/2] dmaengine: usb-dmac: Fix pm_runtime_{enable,disable}() imbalance Geert Uytterhoeven
@ 2015-10-07 14:01 ` Vinod Koul
2015-10-16 13:10 ` Geert Uytterhoeven
2 siblings, 1 reply; 12+ messages in thread
From: Vinod Koul @ 2015-10-07 14:01 UTC (permalink / raw)
To: Geert Uytterhoeven
Cc: Yoshihiro Shimoda, Sergei Shtylyov, dmaengine, linux-sh, linux-pm
On Thu, Oct 01, 2015 at 09:22:16AM +0200, Geert Uytterhoeven wrote:
> Hi Vinod, Shimoda-san,
>
> This series fixes a crash and an imbalance in the usb-dmac driver.
Sorry this fails for me, what was this generated against
--
~Vinod
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH 0/2] dmaengine: usb-dmac: Runtime PM Related Fixes
2015-10-07 14:01 ` [PATCH 0/2] dmaengine: usb-dmac: Runtime PM Related Fixes Vinod Koul
@ 2015-10-16 13:10 ` Geert Uytterhoeven
2015-10-24 12:16 ` Vinod Koul
0 siblings, 1 reply; 12+ messages in thread
From: Geert Uytterhoeven @ 2015-10-16 13:10 UTC (permalink / raw)
To: Vinod Koul
Cc: Geert Uytterhoeven, Yoshihiro Shimoda, Sergei Shtylyov, dmaengine,
Linux-sh list, Linux PM list
Hi Vinod,
On Wed, Oct 7, 2015 at 4:01 PM, Vinod Koul <vinod.koul@intel.com> wrote:
> On Thu, Oct 01, 2015 at 09:22:16AM +0200, Geert Uytterhoeven wrote:
>> Hi Vinod, Shimoda-san,
>>
>> This series fixes a crash and an imbalance in the usb-dmac driver.
>
> Sorry this fails for me, what was this generated against
Strange, this series still applies cleanly on top of slave-dma/next and
linus/master.
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH 0/2] dmaengine: usb-dmac: Runtime PM Related Fixes
2015-10-16 13:10 ` Geert Uytterhoeven
@ 2015-10-24 12:16 ` Vinod Koul
2015-10-24 17:59 ` Geert Uytterhoeven
0 siblings, 1 reply; 12+ messages in thread
From: Vinod Koul @ 2015-10-24 12:16 UTC (permalink / raw)
To: Geert Uytterhoeven
Cc: Geert Uytterhoeven, Yoshihiro Shimoda, Sergei Shtylyov, dmaengine,
Linux-sh list, Linux PM list
On Fri, Oct 16, 2015 at 03:10:37PM +0200, Geert Uytterhoeven wrote:
> Hi Vinod,
>
> On Wed, Oct 7, 2015 at 4:01 PM, Vinod Koul <vinod.koul@intel.com> wrote:
> > On Thu, Oct 01, 2015 at 09:22:16AM +0200, Geert Uytterhoeven wrote:
> >> Hi Vinod, Shimoda-san,
> >>
> >> This series fixes a crash and an imbalance in the usb-dmac driver.
> >
> > Sorry this fails for me, what was this generated against
>
> Strange, this series still applies cleanly on top of slave-dma/next and
> linus/master.
I think I applied this to a new topic branch off rc1. But anyway since I dont
have patches on usb-dma it should have been same :(
--
~Vinod
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH 0/2] dmaengine: usb-dmac: Runtime PM Related Fixes
2015-10-24 12:16 ` Vinod Koul
@ 2015-10-24 17:59 ` Geert Uytterhoeven
2015-10-24 22:56 ` Vinod Koul
0 siblings, 1 reply; 12+ messages in thread
From: Geert Uytterhoeven @ 2015-10-24 17:59 UTC (permalink / raw)
To: Vinod Koul
Cc: Geert Uytterhoeven, Yoshihiro Shimoda, Sergei Shtylyov, dmaengine,
Linux-sh list, Linux PM list
Hi Vinod,
On Sat, Oct 24, 2015 at 2:04 PM, Vinod Koul <vinod.koul@intel.com> wrote:
> On Fri, Oct 16, 2015 at 03:10:37PM +0200, Geert Uytterhoeven wrote:
>> On Wed, Oct 7, 2015 at 4:01 PM, Vinod Koul <vinod.koul@intel.com> wrote:
>> > On Thu, Oct 01, 2015 at 09:22:16AM +0200, Geert Uytterhoeven wrote:
>> >> This series fixes a crash and an imbalance in the usb-dmac driver.
>> >
>> > Sorry this fails for me, what was this generated against
>>
>> Strange, this series still applies cleanly on top of slave-dma/next and
>> linus/master.
>
> I think I applied this to a new topic branch off rc1. But anyway since I dont
> have patches on usb-dma it should have been same :(
So how do we proceed?
Do you want me to resend the patches (they still apply to slave-dma/next)?
Thanks!
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH 0/2] dmaengine: usb-dmac: Runtime PM Related Fixes
2015-10-24 17:59 ` Geert Uytterhoeven
@ 2015-10-24 22:56 ` Vinod Koul
0 siblings, 0 replies; 12+ messages in thread
From: Vinod Koul @ 2015-10-24 22:56 UTC (permalink / raw)
To: Geert Uytterhoeven
Cc: Geert Uytterhoeven, Yoshihiro Shimoda, Sergei Shtylyov, dmaengine,
Linux-sh list, Linux PM list
On Sat, Oct 24, 2015 at 07:59:11PM +0200, Geert Uytterhoeven wrote:
> Hi Vinod,
>
> On Sat, Oct 24, 2015 at 2:04 PM, Vinod Koul <vinod.koul@intel.com> wrote:
> > On Fri, Oct 16, 2015 at 03:10:37PM +0200, Geert Uytterhoeven wrote:
> >> On Wed, Oct 7, 2015 at 4:01 PM, Vinod Koul <vinod.koul@intel.com> wrote:
> >> > On Thu, Oct 01, 2015 at 09:22:16AM +0200, Geert Uytterhoeven wrote:
> >> >> This series fixes a crash and an imbalance in the usb-dmac driver.
> >> >
> >> > Sorry this fails for me, what was this generated against
> >>
> >> Strange, this series still applies cleanly on top of slave-dma/next and
> >> linus/master.
> >
> > I think I applied this to a new topic branch off rc1. But anyway since I dont
> > have patches on usb-dma it should have been same :(
>
> So how do we proceed?
> Do you want me to resend the patches (they still apply to slave-dma/next)?
Yes please and also as a backup can you push a branch with these...
--
~Vinod
^ permalink raw reply [flat|nested] 12+ messages in thread
end of thread, other threads:[~2015-10-24 22:56 UTC | newest]
Thread overview: 12+ messages (download: mbox.gz follow: Atom feed
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2015-10-01 7:22 [PATCH 0/2] dmaengine: usb-dmac: Runtime PM Related Fixes Geert Uytterhoeven
2015-10-01 7:22 ` [PATCH 1/2] dmaengine: usb-dmac: Fix crash on runtime suspend Geert Uytterhoeven
2015-10-01 10:53 ` Yoshihiro Shimoda
2015-10-01 12:26 ` Sergei Shtylyov
2015-10-02 1:00 ` Yoshihiro Shimoda
2015-10-02 10:54 ` Sergei Shtylyov
2015-10-01 7:22 ` [PATCH 2/2] dmaengine: usb-dmac: Fix pm_runtime_{enable,disable}() imbalance Geert Uytterhoeven
2015-10-07 14:01 ` [PATCH 0/2] dmaengine: usb-dmac: Runtime PM Related Fixes Vinod Koul
2015-10-16 13:10 ` Geert Uytterhoeven
2015-10-24 12:16 ` Vinod Koul
2015-10-24 17:59 ` Geert Uytterhoeven
2015-10-24 22:56 ` Vinod Koul
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