| From af6a620395b8cc638cfe298af757c6137aed2d9d Mon Sep 17 00:00:00 2001 |
| From: Sasha Levin <sashal@kernel.org> |
| Date: Mon, 25 May 2020 13:41:25 -0700 |
| Subject: scsi: ufs-qcom: Fix scheduling while atomic issue |
| |
| From: Jeffrey Hugo <jeffrey.l.hugo@gmail.com> |
| |
| [ Upstream commit 3be60b564de49875e47974c37fabced893cd0931 ] |
| |
| ufs_qcom_dump_dbg_regs() uses usleep_range, a sleeping function, but can be |
| called from atomic context in the following flow: |
| |
| ufshcd_intr -> ufshcd_sl_intr -> ufshcd_check_errors -> |
| ufshcd_print_host_regs -> ufshcd_vops_dbg_register_dump -> |
| ufs_qcom_dump_dbg_regs |
| |
| This causes a boot crash on the Lenovo Miix 630 when the interrupt is |
| handled on the idle thread. |
| |
| Fix the issue by switching to udelay(). |
| |
| Link: https://lore.kernel.org/r/20200525204125.46171-1-jeffrey.l.hugo@gmail.com |
| Fixes: 9c46b8676271 ("scsi: ufs-qcom: dump additional testbus registers") |
| Reviewed-by: Bean Huo <beanhuo@micron.com> |
| Reviewed-by: Avri Altman <avri.altman@wdc.com> |
| Signed-off-by: Jeffrey Hugo <jeffrey.l.hugo@gmail.com> |
| Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> |
| Signed-off-by: Sasha Levin <sashal@kernel.org> |
| --- |
| drivers/scsi/ufs/ufs-qcom.c | 6 +++--- |
| 1 file changed, 3 insertions(+), 3 deletions(-) |
| |
| diff --git a/drivers/scsi/ufs/ufs-qcom.c b/drivers/scsi/ufs/ufs-qcom.c |
| index f2b8de195d8af..ee3589ac64abf 100644 |
| --- a/drivers/scsi/ufs/ufs-qcom.c |
| +++ b/drivers/scsi/ufs/ufs-qcom.c |
| @@ -1649,11 +1649,11 @@ static void ufs_qcom_dump_dbg_regs(struct ufs_hba *hba) |
| |
| /* sleep a bit intermittently as we are dumping too much data */ |
| ufs_qcom_print_hw_debug_reg_all(hba, NULL, ufs_qcom_dump_regs_wrapper); |
| - usleep_range(1000, 1100); |
| + udelay(1000); |
| ufs_qcom_testbus_read(hba); |
| - usleep_range(1000, 1100); |
| + udelay(1000); |
| ufs_qcom_print_unipro_testbus(hba); |
| - usleep_range(1000, 1100); |
| + udelay(1000); |
| } |
| |
| /** |
| -- |
| 2.25.1 |
| |
