diff options
| author | John Keeping <john@metanate.com> | 2018-07-17 11:48:16 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-09-26 08:35:05 +0200 |
| commit | 46c66ac938163769834ce38a298c65795ff9e0bc (patch) | |
| tree | d1e1844509520a843adef123b579ba51959e9a1d /drivers | |
| parent | d6ac46c7db364c3dd4b328a9e6616c9f26985f2b (diff) | |
dmaengine: pl330: fix irq race with terminate_all
[ Upstream commit e49756544a21f5625b379b3871d27d8500764670 ]
In pl330_update() when checking if a channel has been aborted, the
channel's lock is not taken, only the overall pl330_dmac lock. But in
pl330_terminate_all() the aborted flag (req_running==-1) is set under
the channel lock and not the pl330_dmac lock.
With threaded interrupts, this leads to a potential race:
pl330_terminate_all pl330_update
------------------- ------------
lock channel
entry
lock pl330
_stop channel
unlock pl330
lock pl330
check req_running != -1
req_running = -1
_start channel
Signed-off-by: John Keeping <john@metanate.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/dma/pl330.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c index 8db791ef2027..95619ee33112 100644 --- a/drivers/dma/pl330.c +++ b/drivers/dma/pl330.c @@ -2132,13 +2132,14 @@ static int pl330_terminate_all(struct dma_chan *chan) pm_runtime_get_sync(pl330->ddma.dev); spin_lock_irqsave(&pch->lock, flags); + spin_lock(&pl330->lock); _stop(pch->thread); - spin_unlock(&pl330->lock); - pch->thread->req[0].desc = NULL; pch->thread->req[1].desc = NULL; pch->thread->req_running = -1; + spin_unlock(&pl330->lock); + power_down = pch->active; pch->active = false; |