6.6-stable review patch. If anyone has any objections, please let me know.
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From: Kyoungrul Kim k831.kim@samsung.com
[ 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@samsung.com Signed-off-by: Minwoo Im minwoo.im@samsung.com Link: https://lore.kernel.org/r/20240627085104epcms2p5897a3870ea5c6416aa44f94df6c5... Reviewed-by: Bart Van Assche bvanassche@acm.org Signed-off-by: Martin K. Petersen martin.petersen@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- 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 ad0ef5b6b8cf..ed59d2367a4e 100644 --- a/drivers/ufs/core/ufshcd.c +++ b/drivers/ufs/core/ufshcd.c @@ -10130,7 +10130,8 @@ 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); @@ -10408,6 +10409,7 @@ 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) { @@ -10489,7 +10491,8 @@ 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);