This is a note to let you know that I've just added the patch titled drivers/dma/pl330.c: fix locking in pl330_free_chan_resources() to the 3.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: drivers-dma-pl330.c-fix-locking-in-pl330_free_chan_resources.patch and it can be found in the queue-3.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From da331ba8e9c5de72a27e50f71105395bba6eebe0 Mon Sep 17 00:00:00 2001 From: Bartlomiej Zolnierkiewicz <b.zolnierkie@xxxxxxxxxxx> Date: Wed, 3 Jul 2013 15:00:43 -0700 Subject: drivers/dma/pl330.c: fix locking in pl330_free_chan_resources() From: Bartlomiej Zolnierkiewicz <b.zolnierkie@xxxxxxxxxxx> 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@xxxxxxxxxxx> Signed-off-by: Kyungmin Park <kyungmin.park@xxxxxxxxxxx> Acked-by: Jassi Brar <jassisinghbrar@xxxxxxxxx> Cc: Vinod Koul <vinod.koul@xxxxxxxxxxxxxxx> Cc: Tomasz Figa <t.figa@xxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/dma/pl330.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/dma/pl330.c +++ b/drivers/dma/pl330.c @@ -2485,10 +2485,10 @@ static void pl330_free_chan_resources(st 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; Patches currently in stable-queue which might be from b.zolnierkie@xxxxxxxxxxx are queue-3.9/drivers-dma-pl330.c-fix-locking-in-pl330_free_chan_resources.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html