lkml.org 
[lkml]   [2013]   [Jul]   [19]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[ 68/72] drivers/dma/pl330.c: fix locking in pl330_free_chan_resources()
    Date
    3.10-stable review patch.  If anyone has any objections, please let me know.

    ------------------

    From: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

    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>

    ---
    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;




    \
     
     \ /
      Last update: 2013-07-19 13:21    [W:4.119 / U:0.056 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site