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| author | John Garry <john.garry@huawei.com> | 2022-05-17 16:04:21 +0800 |
|---|---|---|
| committer | Martin K. Petersen <martin.petersen@oracle.com> | 2022-05-19 20:16:26 -0400 |
| commit | 6c6ac8b7773f05f93dc4e4044686e059d1f78dea (patch) | |
| tree | 28fc4dca36f45be30dc008ba376cd93f3e5be83e | |
| parent | b559b99a5c08194c14dc271e69ca786771b353dc (diff) | |
| download | linux-6c6ac8b7773f05f93dc4e4044686e059d1f78dea.tar.bz2 | |
scsi: hisi_sas: Fix memory ordering in hisi_sas_task_deliver()
The memories for the slot should be observed to be written prior to
observing the slot as ready.
Prior to commit 26fc0ea74fcb ("scsi: libsas: Drop SAS_TASK_AT_INITIATOR"),
we had a spin_lock() + spin_unlock() immediately before marking the slot as
ready. The spin_unlock() - with release semantics - caused the slot memory
to be observed to be written.
Now that the spin_lock() + spin_unlock() is gone, use a smp_wmb().
Link: https://lore.kernel.org/r/1652774661-12935-1-git-send-email-john.garry@huawei.com
Fixes: 26fc0ea74fcb ("scsi: libsas: Drop SAS_TASK_AT_INITIATOR")
Reported-by: Yihang Li <liyihang6@hisilicon.com>
Tested-by: Yihang Li <liyihang6@hisilicon.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
| -rw-r--r-- | drivers/scsi/hisi_sas/hisi_sas_main.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/scsi/hisi_sas/hisi_sas_main.c b/drivers/scsi/hisi_sas/hisi_sas_main.c index f81e74fd6263..764e859d0106 100644 --- a/drivers/scsi/hisi_sas/hisi_sas_main.c +++ b/drivers/scsi/hisi_sas/hisi_sas_main.c @@ -446,6 +446,8 @@ void hisi_sas_task_deliver(struct hisi_hba *hisi_hba, return; } + /* Make slot memories observable before marking as ready */ + smp_wmb(); WRITE_ONCE(slot->ready, 1); spin_lock(&dq->lock); |