This is a note to let you know that I've just added the patch titled
dmaengine: idxd: Protect int_handle field in hw descriptor
to the 6.6-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:
dmaengine-idxd-protect-int_handle-field-in-hw-descri.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 3221f3bebbde03b6b93527ea52bf0c01373f6c56
Author: Guanjun <guanjun@xxxxxxxxxxxxxxxxx>
Date: Mon Dec 11 13:37:03 2023 +0800
dmaengine: idxd: Protect int_handle field in hw descriptor
[ Upstream commit 778dfacc903d4b1ef5b7a9726e3a36bc15913d29 ]
The int_handle field in hw descriptor should also be protected
by wmb() before possibly triggering a DMA read.
Fixes: eb0cf33a91b4 (dmaengine: idxd: move interrupt handle assignment)
Signed-off-by: Guanjun <guanjun@xxxxxxxxxxxxxxxxx>
Reviewed-by: Dave Jiang <dave.jiang@xxxxxxxxx>
Reviewed-by: Fenghua Yu <fenghua.yu@xxxxxxxxx>
Reviewed-by: Lijun Pan <lijun.pan@xxxxxxxxx>
Link: https://lore.kernel.org/r/20231211053704.2725417-2-guanjun@xxxxxxxxxxxxxxxxx
Signed-off-by: Vinod Koul <vkoul@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/dma/idxd/submit.c b/drivers/dma/idxd/submit.c
index c01db23e3333f..3f922518e3a52 100644
--- a/drivers/dma/idxd/submit.c
+++ b/drivers/dma/idxd/submit.c
@@ -182,13 +182,6 @@ int idxd_submit_desc(struct idxd_wq *wq, struct idxd_desc *desc)
portal = idxd_wq_portal_addr(wq);
- /*
- * The wmb() flushes writes to coherent DMA data before
- * possibly triggering a DMA read. The wmb() is necessary
- * even on UP because the recipient is a device.
- */
- wmb();
-
/*
* Pending the descriptor to the lockless list for the irq_entry
* that we designated the descriptor to.
@@ -199,6 +192,13 @@ int idxd_submit_desc(struct idxd_wq *wq, struct idxd_desc *desc)
llist_add(&desc->llnode, &ie->pending_llist);
}
+ /*
+ * The wmb() flushes writes to coherent DMA data before
+ * possibly triggering a DMA read. The wmb() is necessary
+ * even on UP because the recipient is a device.
+ */
+ wmb();
+
if (wq_dedicated(wq)) {
iosubmit_cmds512(portal, desc->hw, 1);
} else {
