dmaengine: at_hdmac: fix race while monitoring channel status
We were reading channel status then taking a lock. This lead to a race because
this lock may delay us and then make this channel not idle anymore.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c
index 3938db2..40f2bf4 100644
--- a/drivers/dma/at_hdmac.c
+++ b/drivers/dma/at_hdmac.c
@@ -853,11 +853,11 @@
dev_vdbg(chan2dev(chan), "issue_pending\n");
+ spin_lock_bh(&atchan->lock);
if (!atc_chan_is_enabled(atchan)) {
- spin_lock_bh(&atchan->lock);
atc_advance_work(atchan);
- spin_unlock_bh(&atchan->lock);
}
+ spin_unlock_bh(&atchan->lock);
}
/**