From: Kyoungrul Kim <k831.kim@xxxxxxxxxxx> [ Upstream commit 7cbff570dbe8907e23bba06f6414899a0fbb2fcc ] 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 has been added, set the scsi_host_added flag to true after adding a SCSI host and check whether it is set or not before removing it. Signed-off-by: Kyoungrul Kim <k831.kim@xxxxxxxxxxx> Signed-off-by: Minwoo Im <minwoo.im@xxxxxxxxxxx> Link: https://lore.kernel.org/r/20240627085104epcms2p5897a3870ea5c6416aa44f94df6c543d7@epcms2p5 Reviewed-by: Bart Van Assche <bvanassche@xxxxxxx> Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- 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 808979a093505..df36b141d4431 100644 --- a/drivers/ufs/core/ufshcd.c +++ b/drivers/ufs/core/ufshcd.c @@ -10114,7 +10114,8 @@ 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); @@ -10389,6 +10390,7 @@ 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) { @@ -10470,7 +10472,8 @@ 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); -- 2.43.0