This is a note to let you know that I've just added the patch titled
net: hns3: use appropriate barrier function after setting a bit value
to the 6.8-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-hns3-use-appropriate-barrier-function-after-sett.patch
and it can be found in the queue-6.8 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 1f8b060a203ce1013ddbbf11d91efd73794ed840
Author: Peiyang Wang <wangpeiyang1@xxxxxxxxxx>
Date: Tue May 7 21:42:22 2024 +0800
net: hns3: use appropriate barrier function after setting a bit value
[ Upstream commit 094c281228529d333458208fd02fcac3b139d93b ]
There is a memory barrier in followed case. When set the port down,
hclgevf_set_timmer will set DOWN in state. Meanwhile, the service task has
different behaviour based on whether the state is DOWN. Thus, to make sure
service task see DOWN, use smp_mb__after_atomic after calling set_bit().
CPU0 CPU1
========================== ===================================
hclgevf_set_timer_task() hclgevf_periodic_service_task()
set_bit(DOWN,state) test_bit(DOWN,state)
pf also has this issue.
Fixes: ff200099d271 ("net: hns3: remove unnecessary work in hclgevf_main")
Fixes: 1c6dfe6fc6f7 ("net: hns3: remove mailbox and reset work in hclge_main")
Signed-off-by: Peiyang Wang <wangpeiyang1@xxxxxxxxxx>
Signed-off-by: Jijie Shao <shaojijie@xxxxxxxxxx>
Reviewed-by: Simon Horman <horms@xxxxxxxxxx>
Signed-off-by: Paolo Abeni <pabeni@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c b/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c
index a5e63655fd88d..a99e42005b9b8 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c
@@ -7944,8 +7944,7 @@ static void hclge_set_timer_task(struct hnae3_handle *handle, bool enable)
/* Set the DOWN flag here to disable link updating */
set_bit(HCLGE_STATE_DOWN, &hdev->state);
- /* flush memory to make sure DOWN is seen by service task */
- smp_mb__before_atomic();
+ smp_mb__after_atomic(); /* flush memory to make sure DOWN is seen by service task */
hclge_flush_link_update(hdev);
}
}
diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c b/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c
index b57111252d071..08db8e84be4ed 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c
@@ -2181,8 +2181,7 @@ static void hclgevf_set_timer_task(struct hnae3_handle *handle, bool enable)
} else {
set_bit(HCLGEVF_STATE_DOWN, &hdev->state);
- /* flush memory to make sure DOWN is seen by service task */
- smp_mb__before_atomic();
+ smp_mb__after_atomic(); /* flush memory to make sure DOWN is seen by service task */
hclgevf_flush_link_update(hdev);
}
}
