If host tries to remove ufshcd driver from a ufs device, it would cause
a kernel panic if ufshcd_async_scan fails during ufshcd_probe_hba before
adding a scsi host with scsi_add_host and MCQ is enabled since scsi host
has been defered after MCQ configuration introduced by Commit
0cab4023ec7b ("scsi: ufs: core: Defer adding host to SCSI if MCQ is
supported").
To guarantee that scsi host is removed only if it's been added, set the
scsi_host_added flag to true after adding a scsi host and check whether
it's set or not before removing the scsi host.
Signed-off-by: Kyoungrul Kim <k831.kim@xxxxxxxxxxx>
Signed-off-by: Minwoo Im <minwoo.im@xxxxxxxxxxx>
---
drivers/ufs/core/ufshcd.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
index a0f8e930167d..101aa08195ce 100644
--- a/drivers/ufs/core/ufshcd.c
+++ b/drivers/ufs/core/ufshcd.c
@@ -10359,7 +10359,8 @@ void ufshcd_remove(struct ufs_hba *hba)
blk_mq_destroy_queue(hba->tmf_queue);
blk_put_queue(hba->tmf_queue);
blk_mq_free_tag_set(&hba->tmf_tag_set);
- scsi_remove_host(hba->host);
+ if (hba->scsi_host_added)
+ scsi_remove_host(hba->host);
/* disable interrupts */
ufshcd_disable_intr(hba, hba->intr_mask);
ufshcd_hba_stop(hba);
@@ -10638,6 +10639,7 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq)
dev_err(hba->dev, "scsi_add_host failed\n");
goto out_disable;
}
+ hba->scsi_host_added = true;
}
hba->tmf_tag_set = (struct blk_mq_tag_set) {
@@ -10720,7 +10722,8 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq)
free_tmf_tag_set:
blk_mq_free_tag_set(&hba->tmf_tag_set);
out_remove_scsi_host:
- scsi_remove_host(hba->host);
+ if (hba->scsi_host_added)
+ scsi_remove_host(hba->host);
out_disable:
hba->is_irq_enabled = false;
ufshcd_hba_exit(hba);
