This is a note to let you know that I've just added the patch titled
net/smc: Fix memory leak when using percpu refs
to the 6.11-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:
net-smc-fix-memory-leak-when-using-percpu-refs.patch
and it can be found in the queue-6.11 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit bda33472c40ba65b76823e5d9d06be5dc45c99e2
Author: Kai Shen <KaiShen@xxxxxxxxxxxxxxxxx>
Date: Thu Oct 10 11:56:24 2024 +0000
net/smc: Fix memory leak when using percpu refs
[ Upstream commit 25c12b459db8365fee84b63f3dd7910f70627f29 ]
This patch adds missing percpu_ref_exit when releasing percpu refs.
When releasing percpu refs, percpu_ref_exit should be called.
Otherwise, memory leak happens.
Fixes: 79a22238b4f2 ("net/smc: Use percpu ref for wr tx reference")
Signed-off-by: Kai Shen <KaiShen@xxxxxxxxxxxxxxxxx>
Reviewed-by: Dust Li <dust.li@xxxxxxxxxxxxxxxxx>
Reviewed-by: Wenjia Zhang <wenjia@xxxxxxxxxxxxx>
Link: https://patch.msgid.link/20241010115624.7769-1-KaiShen@xxxxxxxxxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/net/smc/smc_wr.c b/net/smc/smc_wr.c
index 0021065a600a0..994c0cd4fddbf 100644
--- a/net/smc/smc_wr.c
+++ b/net/smc/smc_wr.c
@@ -648,8 +648,10 @@ void smc_wr_free_link(struct smc_link *lnk)
smc_wr_tx_wait_no_pending_sends(lnk);
percpu_ref_kill(&lnk->wr_reg_refs);
wait_for_completion(&lnk->reg_ref_comp);
+ percpu_ref_exit(&lnk->wr_reg_refs);
percpu_ref_kill(&lnk->wr_tx_refs);
wait_for_completion(&lnk->tx_ref_comp);
+ percpu_ref_exit(&lnk->wr_tx_refs);
if (lnk->wr_rx_dma_addr) {
ib_dma_unmap_single(ibdev, lnk->wr_rx_dma_addr,
@@ -912,11 +914,13 @@ int smc_wr_create_link(struct smc_link *lnk)
init_waitqueue_head(&lnk->wr_reg_wait);
rc = percpu_ref_init(&lnk->wr_reg_refs, smcr_wr_reg_refs_free, 0, GFP_KERNEL);
if (rc)
- goto dma_unmap;
+ goto cancel_ref;
init_completion(&lnk->reg_ref_comp);
init_waitqueue_head(&lnk->wr_rx_empty_wait);
return rc;
+cancel_ref:
+ percpu_ref_exit(&lnk->wr_tx_refs);
dma_unmap:
if (lnk->wr_rx_v2_dma_addr) {
ib_dma_unmap_single(ibdev, lnk->wr_rx_v2_dma_addr,
