summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorAlexandre Bounine <alexandre.bounine@idt.com>2012-03-05 14:59:21 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2012-03-05 15:49:43 -0800
commitb24823e61bfd93d0e72088e4f5245287582ed289 (patch)
treebca721d4235a676cd4cfbfc0d467c9bce5b39fc2
parente6ca7b89dc76abf77c80887fed54e0a60c87c0a8 (diff)
rapidio/tsi721: fix queue wrapping bug in inbound doorbell handler
Fix a bug that causes a kernel panic when the number of received doorbells is larger than number of entries in the inbound doorbell queue (current default value = 512). Another possible indication for this bug is large number of spurious doorbells reported by tsi721 driver after reaching the queue size maximum. Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com> Cc: Chul Kim <chul.kim@idt.com> Cc: Matt Porter <mporter@kernel.crashing.org> Cc: <stable@vger.kernel.org> [3.2.x+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r--drivers/rapidio/devices/tsi721.c5
1 files changed, 3 insertions, 2 deletions
diff --git a/drivers/rapidio/devices/tsi721.c b/drivers/rapidio/devices/tsi721.c
index 691b1ab1a3d0..30d2072f480b 100644
--- a/drivers/rapidio/devices/tsi721.c
+++ b/drivers/rapidio/devices/tsi721.c
@@ -410,13 +410,14 @@ static void tsi721_db_dpc(struct work_struct *work)
*/
mport = priv->mport;
- wr_ptr = ioread32(priv->regs + TSI721_IDQ_WP(IDB_QUEUE));
- rd_ptr = ioread32(priv->regs + TSI721_IDQ_RP(IDB_QUEUE));
+ wr_ptr = ioread32(priv->regs + TSI721_IDQ_WP(IDB_QUEUE)) % IDB_QSIZE;
+ rd_ptr = ioread32(priv->regs + TSI721_IDQ_RP(IDB_QUEUE)) % IDB_QSIZE;
while (wr_ptr != rd_ptr) {
idb_entry = (u64 *)(priv->idb_base +
(TSI721_IDB_ENTRY_SIZE * rd_ptr));
rd_ptr++;
+ rd_ptr %= IDB_QSIZE;
idb.msg = *idb_entry;
*idb_entry = 0;