[PATCH v1] scsi: ufs: core: fix racing issue during ufshcd_mcq_abort

From: SEO HOYOUNG
Date: Mon Nov 13 2023 - 06:28:22 EST


If cq complete irq raise during abort processing,
the command has already been complete.
So could not get utag to erase cmd like below log.
Because the cmd that was handling abort has already been completed

ufshcd_try_to_abort_task: cmd pending in the device. tag = 25
Unable to handle kernel NULL pointer dereference at virtual address
0000000000000194
Mem abort info:
ESR = 0x0000000096000006
EC = 0x25: DABT (current EL), IL = 32 bits
SET = 0, FnV = 0
EA = 0, S1PTW = 0
FSC = 0x06: level 2 translation fault
Data abort info:
ISV = 0, ISS = 0x00000006
CM = 0, WnR = 0

pc : blk_mq_unique_tag+0x8/0x14
lr : ufshcd_mcq_sq_cleanup+0x6c/0x1b8
Call trace:
blk_mq_unique_tag+0x8/0x14
ufshcd_clear_cmd+0x34/0x118
ufshcd_try_to_abort_task+0x1c4/0x4b0
ufshcd_err_handler+0x8d0/0xd24
process_one_work+0x1e4/0x43c
worker_thread+0x25c/0x430
kthread+0x104/0x1d4
ret_from_fork+0x10/0x20

Signed-off-by: SEO HOYOUNG <hy50.seo@xxxxxxxxxxx>
---
drivers/ufs/core/ufshcd.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
index 9a730a794b66..1a58869b91fc 100644
--- a/drivers/ufs/core/ufshcd.c
+++ b/drivers/ufs/core/ufshcd.c
@@ -7574,6 +7574,10 @@ int ufshcd_try_to_abort_task(struct ufs_hba *hba, int tag)
goto out;
}

+ if (!ufshcd_cmd_inflight(cmd) ||
+ test_bit(SCMD_STATE_COMPLETE, &cmd->state))
+ goto out;
+
err = ufshcd_clear_cmd(hba, tag);
if (err)
dev_err(hba->dev, "%s: Failed clearing cmd at tag %d, err %d\n",
--
2.26.0