This is a note to let you know that I've just added the patch titled
scsi: megaraid_sas: Fix for a potential deadlock
to the 5.4-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:
scsi-megaraid_sas-fix-for-a-potential-deadlock.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 1e6457deacce90c3ad58c29639264b0ea17e06b1
Author: Tomas Henzl <thenzl@xxxxxxxxxx>
Date: Mon Sep 23 19:48:33 2024 +0200
scsi: megaraid_sas: Fix for a potential deadlock
[ Upstream commit 50740f4dc78b41dec7c8e39772619d5ba841ddd7 ]
This fixes a 'possible circular locking dependency detected' warning
CPU0 CPU1
---- ----
lock(&instance->reset_mutex);
lock(&shost->scan_mutex);
lock(&instance->reset_mutex);
lock(&shost->scan_mutex);
Fix this by temporarily releasing the reset_mutex.
Signed-off-by: Tomas Henzl <thenzl@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20240923174833.45345-1-thenzl@xxxxxxxxxx
Acked-by: Chandrakanth Patil <chandrakanth.patil@xxxxxxxxxxxx>
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/scsi/megaraid/megaraid_sas_base.c b/drivers/scsi/megaraid/megaraid_sas_base.c
index 603c99fcb74e..7f2d12c5dc4b 100644
--- a/drivers/scsi/megaraid/megaraid_sas_base.c
+++ b/drivers/scsi/megaraid/megaraid_sas_base.c
@@ -8802,8 +8802,11 @@ megasas_aen_polling(struct work_struct *work)
(ld_target_id / MEGASAS_MAX_DEV_PER_CHANNEL),
(ld_target_id - MEGASAS_MAX_DEV_PER_CHANNEL),
0);
- if (sdev1)
+ if (sdev1) {
+ mutex_unlock(&instance->reset_mutex);
megasas_remove_scsi_device(sdev1);
+ mutex_lock(&instance->reset_mutex);
+ }
event_type = SCAN_VD_CHANNEL;
break;
