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| author | Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> | 2013-07-03 15:00:43 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-07-21 18:21:35 -0700 |
| commit | c14a4eaf8a43a295176942c7a43a999b4557f7c3 (patch) | |
| tree | c3b9a1e103edfef1d5babbcf78597d8deaee1364 | |
| parent | 9131e72c764bd7ea9554392edab26a368a765c4d (diff) | |
| download | lwn-c14a4eaf8a43a295176942c7a43a999b4557f7c3.tar.gz lwn-c14a4eaf8a43a295176942c7a43a999b4557f7c3.zip | |
drivers/dma/pl330.c: fix locking in pl330_free_chan_resources()
commit da331ba8e9c5de72a27e50f71105395bba6eebe0 upstream.
tasklet_kill() may sleep so call it before taking pch->lock.
Fixes following lockup:
BUG: scheduling while atomic: cat/2383/0x00000002
Modules linked in:
unwind_backtrace+0x0/0xfc
__schedule_bug+0x4c/0x58
__schedule+0x690/0x6e0
sys_sched_yield+0x70/0x78
tasklet_kill+0x34/0x8c
pl330_free_chan_resources+0x24/0x88
dma_chan_put+0x4c/0x50
[...]
BUG: spinlock lockup suspected on CPU#0, swapper/0/0
lock: 0xe52aa04c, .magic: dead4ead, .owner: cat/2383, .owner_cpu: 1
unwind_backtrace+0x0/0xfc
do_raw_spin_lock+0x194/0x204
_raw_spin_lock_irqsave+0x20/0x28
pl330_tasklet+0x2c/0x5a8
tasklet_action+0xfc/0x114
__do_softirq+0xe4/0x19c
irq_exit+0x98/0x9c
handle_IPI+0x124/0x16c
gic_handle_irq+0x64/0x68
__irq_svc+0x40/0x70
cpuidle_wrap_enter+0x4c/0xa0
cpuidle_enter_state+0x18/0x68
cpuidle_idle_call+0xac/0xe0
cpu_idle+0xac/0xf0
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Jassi Brar <jassisinghbrar@gmail.com>
Cc: Vinod Koul <vinod.koul@linux.intel.com>
Cc: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/dma/pl330.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c index a17553f7c028..7ec82f0667eb 100644 --- a/drivers/dma/pl330.c +++ b/drivers/dma/pl330.c @@ -2485,10 +2485,10 @@ static void pl330_free_chan_resources(struct dma_chan *chan) struct dma_pl330_chan *pch = to_pchan(chan); unsigned long flags; - spin_lock_irqsave(&pch->lock, flags); - tasklet_kill(&pch->task); + spin_lock_irqsave(&pch->lock, flags); + pl330_release_channel(pch->pl330_chid); pch->pl330_chid = NULL; |