| Message ID | f1de8d306e45127bdcb53b4ee53a7d5dc3c5c95b.1507935819.git.shuahkh@osg.samsung.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 10/16/2017 05:16 PM, Shuah Khan wrote: > The driver mmap functions shouldn't take lock when calling vb2_mmap(). > Fix it to not take the lock. > > Reference: commit log for f035eb4e976ef5a059e30bc91cfd310ff030a7d3 > and e752577ed7bf55c81e10343fced8b378cda2b63b > > The following lockdep warning is fixed with this change. > > [ 1990.972058] ====================================================== > [ 1990.978172] WARNING: possible circular locking dependency detected > [ 1990.984327] 4.14.0-rc2-00002-gfab205f-dirty #4 Not tainted > [ 1990.989783] ------------------------------------------------------ > [ 1990.995937] qtdemux0:sink/2765 is trying to acquire lock: > [ 1991.001309] (&gsc->lock){+.+.}, at: [<bf1729f0>] gsc_m2m_mmap+0x24/0x5c [exynos_gsc] > [ 1991.009108] > but task is already holding lock: > [ 1991.014913] (&mm->mmap_sem){++++}, at: [<c01df2e4>] vm_mmap_pgoff+0x44/0xb8 > [ 1991.021932] > which lock already depends on the new lock. > > [ 1991.030078] > the existing dependency chain (in reverse order) is: > [ 1991.037530] > -> #1 (&mm->mmap_sem){++++}: > [ 1991.042913] __might_fault+0x80/0xb0 > [ 1991.047096] video_usercopy+0x1cc/0x510 [videodev] > [ 1991.052297] v4l2_ioctl+0xa4/0xdc [videodev] > [ 1991.057036] do_vfs_ioctl+0xa0/0xa18 > [ 1991.061102] SyS_ioctl+0x34/0x5c > [ 1991.064834] ret_fast_syscall+0x0/0x28 > [ 1991.069072] > -> #0 (&gsc->lock){+.+.}: > [ 1991.074193] lock_acquire+0x6c/0x88 > [ 1991.078179] __mutex_lock+0x68/0xa34 > [ 1991.082247] mutex_lock_interruptible_nested+0x1c/0x24 > [ 1991.087888] gsc_m2m_mmap+0x24/0x5c [exynos_gsc] > [ 1991.093029] v4l2_mmap+0x54/0x88 [videodev] > [ 1991.097673] mmap_region+0x3a8/0x638 > [ 1991.101743] do_mmap+0x330/0x3a4 > [ 1991.105470] vm_mmap_pgoff+0x90/0xb8 > [ 1991.109542] SyS_mmap_pgoff+0x90/0xc0 > [ 1991.113702] ret_fast_syscall+0x0/0x28 > [ 1991.117945] > other info that might help us debug this: > > [ 1991.125918] Possible unsafe locking scenario: > > [ 1991.131810] CPU0 CPU1 > [ 1991.136315] ---- ---- > [ 1991.140821] lock(&mm->mmap_sem); > [ 1991.144201] lock(&gsc->lock); > [ 1991.149833] lock(&mm->mmap_sem); > [ 1991.155725] lock(&gsc->lock); > [ 1991.158845] > *** DEADLOCK *** > > [ 1991.164740] 1 lock held by qtdemux0:sink/2765: > [ 1991.169157] #0: (&mm->mmap_sem){++++}, at: [<c01df2e4>] vm_mmap_pgoff+0x44/0xb8 > [ 1991.176609] > stack backtrace: > [ 1991.180946] CPU: 2 PID: 2765 Comm: qtdemux0:sink Not tainted 4.14.0-rc2-00002-gfab205f-dirty #4 > [ 1991.189608] Hardware name: SAMSUNG EXYNOS (Flattened Device Tree) > [ 1991.195686] [<c01102c8>] (unwind_backtrace) from [<c010cabc>] (show_stack+0x10/0x14) > [ 1991.203393] [<c010cabc>] (show_stack) from [<c08543a4>] (dump_stack+0x98/0xc4) > [ 1991.210586] [<c08543a4>] (dump_stack) from [<c016b2fc>] (print_circular_bug+0x254/0x410) > [ 1991.218644] [<c016b2fc>] (print_circular_bug) from [<c016c580>] (check_prev_add+0x468/0x938) > [ 1991.227049] [<c016c580>] (check_prev_add) from [<c016f4dc>] (__lock_acquire+0x1314/0x14fc) > [ 1991.235281] [<c016f4dc>] (__lock_acquire) from [<c016fefc>] (lock_acquire+0x6c/0x88) > [ 1991.242993] [<c016fefc>] (lock_acquire) from [<c0869fb4>] (__mutex_lock+0x68/0xa34) > [ 1991.250620] [<c0869fb4>] (__mutex_lock) from [<c086aa08>] (mutex_lock_interruptible_nested+0x1c/0x24) > [ 1991.259812] [<c086aa08>] (mutex_lock_interruptible_nested) from [<bf1729f0>] (gsc_m2m_mmap+0x24/0x5c [exynos_gsc]) > [ 1991.270159] [<bf1729f0>] (gsc_m2m_mmap [exynos_gsc]) from [<bf037120>] (v4l2_mmap+0x54/0x88 [videodev]) > [ 1991.279510] [<bf037120>] (v4l2_mmap [videodev]) from [<c01f4798>] (mmap_region+0x3a8/0x638) > [ 1991.287792] [<c01f4798>] (mmap_region) from [<c01f4d58>] (do_mmap+0x330/0x3a4) > [ 1991.294986] [<c01f4d58>] (do_mmap) from [<c01df330>] (vm_mmap_pgoff+0x90/0xb8) > [ 1991.302178] [<c01df330>] (vm_mmap_pgoff) from [<c01f28cc>] (SyS_mmap_pgoff+0x90/0xc0) > [ 1991.309977] [<c01f28cc>] (SyS_mmap_pgoff) from [<c0108820>] (ret_fast_syscall+0x0/0x28) > > Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com> > Suggested-by: Hans Verkuil <hansverk@cisco.com> > Acked-by: Marek Szyprowski <m.szyprowski@samsung.com> Acked-by: Hans Verkuil <hansverk@cisco.com> Regards, Hans > --- > drivers/media/platform/exynos-gsc/gsc-m2m.c | 5 ----- > 1 file changed, 5 deletions(-) > > diff --git a/drivers/media/platform/exynos-gsc/gsc-m2m.c b/drivers/media/platform/exynos-gsc/gsc-m2m.c > index 2a2994e..722d7c4 100644 > --- a/drivers/media/platform/exynos-gsc/gsc-m2m.c > +++ b/drivers/media/platform/exynos-gsc/gsc-m2m.c > @@ -726,14 +726,9 @@ static unsigned int gsc_m2m_poll(struct file *file, > static int gsc_m2m_mmap(struct file *file, struct vm_area_struct *vma) > { > struct gsc_ctx *ctx = fh_to_ctx(file->private_data); > - struct gsc_dev *gsc = ctx->gsc_dev; > int ret; > > - if (mutex_lock_interruptible(&gsc->lock)) > - return -ERESTARTSYS; > - > ret = v4l2_m2m_mmap(file, ctx->m2m_ctx, vma); > - mutex_unlock(&gsc->lock); > > return ret; > } >
On 10/16/2017 09:18 AM, Hans Verkuil wrote: > On 10/16/2017 05:16 PM, Shuah Khan wrote: >> The driver mmap functions shouldn't take lock when calling vb2_mmap(). >> Fix it to not take the lock. >> >> Reference: commit log for f035eb4e976ef5a059e30bc91cfd310ff030a7d3 >> and e752577ed7bf55c81e10343fced8b378cda2b63b >> >> The following lockdep warning is fixed with this change. >> >> [ 1990.972058] ====================================================== >> [ 1990.978172] WARNING: possible circular locking dependency detected >> [ 1990.984327] 4.14.0-rc2-00002-gfab205f-dirty #4 Not tainted >> [ 1990.989783] ------------------------------------------------------ >> [ 1990.995937] qtdemux0:sink/2765 is trying to acquire lock: >> [ 1991.001309] (&gsc->lock){+.+.}, at: [<bf1729f0>] gsc_m2m_mmap+0x24/0x5c [exynos_gsc] >> [ 1991.009108] >> but task is already holding lock: >> [ 1991.014913] (&mm->mmap_sem){++++}, at: [<c01df2e4>] vm_mmap_pgoff+0x44/0xb8 >> [ 1991.021932] >> which lock already depends on the new lock. >> >> [ 1991.030078] >> the existing dependency chain (in reverse order) is: >> [ 1991.037530] >> -> #1 (&mm->mmap_sem){++++}: >> [ 1991.042913] __might_fault+0x80/0xb0 >> [ 1991.047096] video_usercopy+0x1cc/0x510 [videodev] >> [ 1991.052297] v4l2_ioctl+0xa4/0xdc [videodev] >> [ 1991.057036] do_vfs_ioctl+0xa0/0xa18 >> [ 1991.061102] SyS_ioctl+0x34/0x5c >> [ 1991.064834] ret_fast_syscall+0x0/0x28 >> [ 1991.069072] >> -> #0 (&gsc->lock){+.+.}: >> [ 1991.074193] lock_acquire+0x6c/0x88 >> [ 1991.078179] __mutex_lock+0x68/0xa34 >> [ 1991.082247] mutex_lock_interruptible_nested+0x1c/0x24 >> [ 1991.087888] gsc_m2m_mmap+0x24/0x5c [exynos_gsc] >> [ 1991.093029] v4l2_mmap+0x54/0x88 [videodev] >> [ 1991.097673] mmap_region+0x3a8/0x638 >> [ 1991.101743] do_mmap+0x330/0x3a4 >> [ 1991.105470] vm_mmap_pgoff+0x90/0xb8 >> [ 1991.109542] SyS_mmap_pgoff+0x90/0xc0 >> [ 1991.113702] ret_fast_syscall+0x0/0x28 >> [ 1991.117945] >> other info that might help us debug this: >> >> [ 1991.125918] Possible unsafe locking scenario: >> >> [ 1991.131810] CPU0 CPU1 >> [ 1991.136315] ---- ---- >> [ 1991.140821] lock(&mm->mmap_sem); >> [ 1991.144201] lock(&gsc->lock); >> [ 1991.149833] lock(&mm->mmap_sem); >> [ 1991.155725] lock(&gsc->lock); >> [ 1991.158845] >> *** DEADLOCK *** >> >> [ 1991.164740] 1 lock held by qtdemux0:sink/2765: >> [ 1991.169157] #0: (&mm->mmap_sem){++++}, at: [<c01df2e4>] vm_mmap_pgoff+0x44/0xb8 >> [ 1991.176609] >> stack backtrace: >> [ 1991.180946] CPU: 2 PID: 2765 Comm: qtdemux0:sink Not tainted 4.14.0-rc2-00002-gfab205f-dirty #4 >> [ 1991.189608] Hardware name: SAMSUNG EXYNOS (Flattened Device Tree) >> [ 1991.195686] [<c01102c8>] (unwind_backtrace) from [<c010cabc>] (show_stack+0x10/0x14) >> [ 1991.203393] [<c010cabc>] (show_stack) from [<c08543a4>] (dump_stack+0x98/0xc4) >> [ 1991.210586] [<c08543a4>] (dump_stack) from [<c016b2fc>] (print_circular_bug+0x254/0x410) >> [ 1991.218644] [<c016b2fc>] (print_circular_bug) from [<c016c580>] (check_prev_add+0x468/0x938) >> [ 1991.227049] [<c016c580>] (check_prev_add) from [<c016f4dc>] (__lock_acquire+0x1314/0x14fc) >> [ 1991.235281] [<c016f4dc>] (__lock_acquire) from [<c016fefc>] (lock_acquire+0x6c/0x88) >> [ 1991.242993] [<c016fefc>] (lock_acquire) from [<c0869fb4>] (__mutex_lock+0x68/0xa34) >> [ 1991.250620] [<c0869fb4>] (__mutex_lock) from [<c086aa08>] (mutex_lock_interruptible_nested+0x1c/0x24) >> [ 1991.259812] [<c086aa08>] (mutex_lock_interruptible_nested) from [<bf1729f0>] (gsc_m2m_mmap+0x24/0x5c [exynos_gsc]) >> [ 1991.270159] [<bf1729f0>] (gsc_m2m_mmap [exynos_gsc]) from [<bf037120>] (v4l2_mmap+0x54/0x88 [videodev]) >> [ 1991.279510] [<bf037120>] (v4l2_mmap [videodev]) from [<c01f4798>] (mmap_region+0x3a8/0x638) >> [ 1991.287792] [<c01f4798>] (mmap_region) from [<c01f4d58>] (do_mmap+0x330/0x3a4) >> [ 1991.294986] [<c01f4d58>] (do_mmap) from [<c01df330>] (vm_mmap_pgoff+0x90/0xb8) >> [ 1991.302178] [<c01df330>] (vm_mmap_pgoff) from [<c01f28cc>] (SyS_mmap_pgoff+0x90/0xc0) >> [ 1991.309977] [<c01f28cc>] (SyS_mmap_pgoff) from [<c0108820>] (ret_fast_syscall+0x0/0x28) >> >> Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com> >> Suggested-by: Hans Verkuil <hansverk@cisco.com> >> Acked-by: Marek Szyprowski <m.szyprowski@samsung.com> > > Acked-by: Hans Verkuil <hansverk@cisco.com> > > Regards, > > Hans Hi Mauro, Are you planning to take this in for 4.15-rc1? This patch is applicable to stable as well. thanks, -- Shuah
On 11/07/2017 09:53 AM, Shuah Khan wrote: > On 10/16/2017 09:18 AM, Hans Verkuil wrote: >> On 10/16/2017 05:16 PM, Shuah Khan wrote: >>> The driver mmap functions shouldn't take lock when calling vb2_mmap(). >>> Fix it to not take the lock. >>> >>> Reference: commit log for f035eb4e976ef5a059e30bc91cfd310ff030a7d3 >>> and e752577ed7bf55c81e10343fced8b378cda2b63b >>> >>> The following lockdep warning is fixed with this change. >>> >>> [ 1990.972058] ====================================================== >>> [ 1990.978172] WARNING: possible circular locking dependency detected >>> [ 1990.984327] 4.14.0-rc2-00002-gfab205f-dirty #4 Not tainted >>> [ 1990.989783] ------------------------------------------------------ >>> [ 1990.995937] qtdemux0:sink/2765 is trying to acquire lock: >>> [ 1991.001309] (&gsc->lock){+.+.}, at: [<bf1729f0>] gsc_m2m_mmap+0x24/0x5c [exynos_gsc] >>> [ 1991.009108] >>> but task is already holding lock: >>> [ 1991.014913] (&mm->mmap_sem){++++}, at: [<c01df2e4>] vm_mmap_pgoff+0x44/0xb8 >>> [ 1991.021932] >>> which lock already depends on the new lock. >>> >>> [ 1991.030078] >>> the existing dependency chain (in reverse order) is: >>> [ 1991.037530] >>> -> #1 (&mm->mmap_sem){++++}: >>> [ 1991.042913] __might_fault+0x80/0xb0 >>> [ 1991.047096] video_usercopy+0x1cc/0x510 [videodev] >>> [ 1991.052297] v4l2_ioctl+0xa4/0xdc [videodev] >>> [ 1991.057036] do_vfs_ioctl+0xa0/0xa18 >>> [ 1991.061102] SyS_ioctl+0x34/0x5c >>> [ 1991.064834] ret_fast_syscall+0x0/0x28 >>> [ 1991.069072] >>> -> #0 (&gsc->lock){+.+.}: >>> [ 1991.074193] lock_acquire+0x6c/0x88 >>> [ 1991.078179] __mutex_lock+0x68/0xa34 >>> [ 1991.082247] mutex_lock_interruptible_nested+0x1c/0x24 >>> [ 1991.087888] gsc_m2m_mmap+0x24/0x5c [exynos_gsc] >>> [ 1991.093029] v4l2_mmap+0x54/0x88 [videodev] >>> [ 1991.097673] mmap_region+0x3a8/0x638 >>> [ 1991.101743] do_mmap+0x330/0x3a4 >>> [ 1991.105470] vm_mmap_pgoff+0x90/0xb8 >>> [ 1991.109542] SyS_mmap_pgoff+0x90/0xc0 >>> [ 1991.113702] ret_fast_syscall+0x0/0x28 >>> [ 1991.117945] >>> other info that might help us debug this: >>> >>> [ 1991.125918] Possible unsafe locking scenario: >>> >>> [ 1991.131810] CPU0 CPU1 >>> [ 1991.136315] ---- ---- >>> [ 1991.140821] lock(&mm->mmap_sem); >>> [ 1991.144201] lock(&gsc->lock); >>> [ 1991.149833] lock(&mm->mmap_sem); >>> [ 1991.155725] lock(&gsc->lock); >>> [ 1991.158845] >>> *** DEADLOCK *** >>> >>> [ 1991.164740] 1 lock held by qtdemux0:sink/2765: >>> [ 1991.169157] #0: (&mm->mmap_sem){++++}, at: [<c01df2e4>] vm_mmap_pgoff+0x44/0xb8 >>> [ 1991.176609] >>> stack backtrace: >>> [ 1991.180946] CPU: 2 PID: 2765 Comm: qtdemux0:sink Not tainted 4.14.0-rc2-00002-gfab205f-dirty #4 >>> [ 1991.189608] Hardware name: SAMSUNG EXYNOS (Flattened Device Tree) >>> [ 1991.195686] [<c01102c8>] (unwind_backtrace) from [<c010cabc>] (show_stack+0x10/0x14) >>> [ 1991.203393] [<c010cabc>] (show_stack) from [<c08543a4>] (dump_stack+0x98/0xc4) >>> [ 1991.210586] [<c08543a4>] (dump_stack) from [<c016b2fc>] (print_circular_bug+0x254/0x410) >>> [ 1991.218644] [<c016b2fc>] (print_circular_bug) from [<c016c580>] (check_prev_add+0x468/0x938) >>> [ 1991.227049] [<c016c580>] (check_prev_add) from [<c016f4dc>] (__lock_acquire+0x1314/0x14fc) >>> [ 1991.235281] [<c016f4dc>] (__lock_acquire) from [<c016fefc>] (lock_acquire+0x6c/0x88) >>> [ 1991.242993] [<c016fefc>] (lock_acquire) from [<c0869fb4>] (__mutex_lock+0x68/0xa34) >>> [ 1991.250620] [<c0869fb4>] (__mutex_lock) from [<c086aa08>] (mutex_lock_interruptible_nested+0x1c/0x24) >>> [ 1991.259812] [<c086aa08>] (mutex_lock_interruptible_nested) from [<bf1729f0>] (gsc_m2m_mmap+0x24/0x5c [exynos_gsc]) >>> [ 1991.270159] [<bf1729f0>] (gsc_m2m_mmap [exynos_gsc]) from [<bf037120>] (v4l2_mmap+0x54/0x88 [videodev]) >>> [ 1991.279510] [<bf037120>] (v4l2_mmap [videodev]) from [<c01f4798>] (mmap_region+0x3a8/0x638) >>> [ 1991.287792] [<c01f4798>] (mmap_region) from [<c01f4d58>] (do_mmap+0x330/0x3a4) >>> [ 1991.294986] [<c01f4d58>] (do_mmap) from [<c01df330>] (vm_mmap_pgoff+0x90/0xb8) >>> [ 1991.302178] [<c01df330>] (vm_mmap_pgoff) from [<c01f28cc>] (SyS_mmap_pgoff+0x90/0xc0) >>> [ 1991.309977] [<c01f28cc>] (SyS_mmap_pgoff) from [<c0108820>] (ret_fast_syscall+0x0/0x28) >>> >>> Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com> >>> Suggested-by: Hans Verkuil <hansverk@cisco.com> >>> Acked-by: Marek Szyprowski <m.szyprowski@samsung.com> >> >> Acked-by: Hans Verkuil <hansverk@cisco.com> >> >> Regards, >> >> Hans > > Hi Mauro, > > Are you planning to take this in for 4.15-rc1? This patch is applicable > to stable as well. > > thanks, > -- Shuah > Hi Mauro, Doesn't look like this fox made it into 4.15-rc2 - do you plan to get this into 4.15 at some point? I am seeing this lockdep warning in 4.15-rc2 thanks, -- Shuah
diff --git a/drivers/media/platform/exynos-gsc/gsc-m2m.c b/drivers/media/platform/exynos-gsc/gsc-m2m.c index 2a2994e..722d7c4 100644 --- a/drivers/media/platform/exynos-gsc/gsc-m2m.c +++ b/drivers/media/platform/exynos-gsc/gsc-m2m.c @@ -726,14 +726,9 @@ static unsigned int gsc_m2m_poll(struct file *file, static int gsc_m2m_mmap(struct file *file, struct vm_area_struct *vma) { struct gsc_ctx *ctx = fh_to_ctx(file->private_data); - struct gsc_dev *gsc = ctx->gsc_dev; int ret; - if (mutex_lock_interruptible(&gsc->lock)) - return -ERESTARTSYS; - ret = v4l2_m2m_mmap(file, ctx->m2m_ctx, vma); - mutex_unlock(&gsc->lock); return ret; }
The driver mmap functions shouldn't take lock when calling vb2_mmap(). Fix it to not take the lock. The following lockdep warning is fixed with this change. [ 1990.972058] ====================================================== [ 1990.978172] WARNING: possible circular locking dependency detected [ 1990.984327] 4.14.0-rc2-00002-gfab205f-dirty #4 Not tainted [ 1990.989783] ------------------------------------------------------ [ 1990.995937] qtdemux0:sink/2765 is trying to acquire lock: [ 1991.001309] (&gsc->lock){+.+.}, at: [<bf1729f0>] gsc_m2m_mmap+0x24/0x5c [exynos_gsc] [ 1991.009108] but task is already holding lock: [ 1991.014913] (&mm->mmap_sem){++++}, at: [<c01df2e4>] vm_mmap_pgoff+0x44/0xb8 [ 1991.021932] which lock already depends on the new lock. [ 1991.030078] the existing dependency chain (in reverse order) is: [ 1991.037530] -> #1 (&mm->mmap_sem){++++}: [ 1991.042913] __might_fault+0x80/0xb0 [ 1991.047096] video_usercopy+0x1cc/0x510 [videodev] [ 1991.052297] v4l2_ioctl+0xa4/0xdc [videodev] [ 1991.057036] do_vfs_ioctl+0xa0/0xa18 [ 1991.061102] SyS_ioctl+0x34/0x5c [ 1991.064834] ret_fast_syscall+0x0/0x28 [ 1991.069072] -> #0 (&gsc->lock){+.+.}: [ 1991.074193] lock_acquire+0x6c/0x88 [ 1991.078179] __mutex_lock+0x68/0xa34 [ 1991.082247] mutex_lock_interruptible_nested+0x1c/0x24 [ 1991.087888] gsc_m2m_mmap+0x24/0x5c [exynos_gsc] [ 1991.093029] v4l2_mmap+0x54/0x88 [videodev] [ 1991.097673] mmap_region+0x3a8/0x638 [ 1991.101743] do_mmap+0x330/0x3a4 [ 1991.105470] vm_mmap_pgoff+0x90/0xb8 [ 1991.109542] SyS_mmap_pgoff+0x90/0xc0 [ 1991.113702] ret_fast_syscall+0x0/0x28 [ 1991.117945] other info that might help us debug this: [ 1991.125918] Possible unsafe locking scenario: [ 1991.131810] CPU0 CPU1 [ 1991.136315] ---- ---- [ 1991.140821] lock(&mm->mmap_sem); [ 1991.144201] lock(&gsc->lock); [ 1991.149833] lock(&mm->mmap_sem); [ 1991.155725] lock(&gsc->lock); [ 1991.158845] *** DEADLOCK *** [ 1991.164740] 1 lock held by qtdemux0:sink/2765: [ 1991.169157] #0: (&mm->mmap_sem){++++}, at: [<c01df2e4>] vm_mmap_pgoff+0x44/0xb8 [ 1991.176609] stack backtrace: [ 1991.180946] CPU: 2 PID: 2765 Comm: qtdemux0:sink Not tainted 4.14.0-rc2-00002-gfab205f-dirty #4 [ 1991.189608] Hardware name: SAMSUNG EXYNOS (Flattened Device Tree) [ 1991.195686] [<c01102c8>] (unwind_backtrace) from [<c010cabc>] (show_stack+0x10/0x14) [ 1991.203393] [<c010cabc>] (show_stack) from [<c08543a4>] (dump_stack+0x98/0xc4) [ 1991.210586] [<c08543a4>] (dump_stack) from [<c016b2fc>] (print_circular_bug+0x254/0x410) [ 1991.218644] [<c016b2fc>] (print_circular_bug) from [<c016c580>] (check_prev_add+0x468/0x938) [ 1991.227049] [<c016c580>] (check_prev_add) from [<c016f4dc>] (__lock_acquire+0x1314/0x14fc) [ 1991.235281] [<c016f4dc>] (__lock_acquire) from [<c016fefc>] (lock_acquire+0x6c/0x88) [ 1991.242993] [<c016fefc>] (lock_acquire) from [<c0869fb4>] (__mutex_lock+0x68/0xa34) [ 1991.250620] [<c0869fb4>] (__mutex_lock) from [<c086aa08>] (mutex_lock_interruptible_nested+0x1c/0x24) [ 1991.259812] [<c086aa08>] (mutex_lock_interruptible_nested) from [<bf1729f0>] (gsc_m2m_mmap+0x24/0x5c [exynos_gsc]) [ 1991.270159] [<bf1729f0>] (gsc_m2m_mmap [exynos_gsc]) from [<bf037120>] (v4l2_mmap+0x54/0x88 [videodev]) [ 1991.279510] [<bf037120>] (v4l2_mmap [videodev]) from [<c01f4798>] (mmap_region+0x3a8/0x638) [ 1991.287792] [<c01f4798>] (mmap_region) from [<c01f4d58>] (do_mmap+0x330/0x3a4) [ 1991.294986] [<c01f4d58>] (do_mmap) from [<c01df330>] (vm_mmap_pgoff+0x90/0xb8) [ 1991.302178] [<c01df330>] (vm_mmap_pgoff) from [<c01f28cc>] (SyS_mmap_pgoff+0x90/0xc0) [ 1991.309977] [<c01f28cc>] (SyS_mmap_pgoff) from [<c0108820>] (ret_fast_syscall+0x0/0x28) Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com> Suggested-by: Hans Verkuil <hansverk@cisco.com> --- drivers/media/platform/exynos-gsc/gsc-m2m.c | 5 ----- 1 file changed, 5 deletions(-)