[PATCH 1/2] Revert "scsi: core: Do not increase scsi_device's iorequest_cnt if dispatch failed"

From: Wenchao Hao
Date: Mon May 15 2023 - 03:02:31 EST


the "atomic_inc(&cmd->device->iorequest_cnt)" in scsi_queue_rq() would
causes kernel panic, because cmd->device may be freed after returning
from scsi_dispatch_cmd().

This reverts commit cfee29ffb45b1c9798011b19d454637d1b0fe87d.

Signed-off-by: Wenchao Hao <haowenchao2@xxxxxxxxxx>
Reported-by: Ming Lei <ming.lei@xxxxxxxxxx>
Closes:https://lore.kernel.org/linux-scsi/8e0f2d31-e6ff-ec4a-3974-450560ad49c5@xxxxxxxxxx/T/#t
---
drivers/scsi/scsi_lib.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index b7c569a42aa4..03964b26f3f2 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -1463,6 +1463,8 @@ static int scsi_dispatch_cmd(struct scsi_cmnd *cmd)
struct Scsi_Host *host = cmd->device->host;
int rtn = 0;

+ atomic_inc(&cmd->device->iorequest_cnt);
+
/* check if the device is still usable */
if (unlikely(cmd->device->sdev_state == SDEV_DEL)) {
/* in SDEV_DEL we error all commands. DID_NO_CONNECT
@@ -1761,7 +1763,6 @@ static blk_status_t scsi_queue_rq(struct blk_mq_hw_ctx *hctx,
goto out_dec_host_busy;
}

- atomic_inc(&cmd->device->iorequest_cnt);
return BLK_STS_OK;

out_dec_host_busy:
--
2.32.0