Re: [PATCH 2/2] scsi: ufs: Fix tm request when non-fatal error happens

On Tue, Nov 16, 2021 at 06:48:31PM +0800, Orson Zhai wrote:

From: Jaegeuk Kim jaegeuk@kernel.org

[ Upstream commit eeb1b55b6e25c5f7265ff45cd050f3bc2cc423a4 ]

When non-fatal error like line-reset happens, ufshcd_err_handler() starts to abort tasks by ufshcd_try_to_abort_task(). When it tries to issue a task management request, we hit two warnings:

WARNING: CPU: 7 PID: 7 at block/blk-core.c:630 blk_get_request+0x68/0x70 WARNING: CPU: 4 PID: 157 at block/blk-mq-tag.c:82 blk_mq_get_tag+0x438/0x46c

After fixing the above warnings we hit another tm_cmd timeout which may be caused by unstable controller state:

__ufshcd_issue_tm_cmd: task management cmd 0x80 timed-out

Then, ufshcd_err_handler() enters full reset, and kernel gets stuck. It turned out ufshcd_print_trs() printed too many messages on console which requires CPU locks. Likewise hba->silence_err_logs, we need to avoid too verbose messages. This is actually not an error case.

Change-Id: I8a422b1f0e3152191f576548cc371a1a41115f59 Link: https://lore.kernel.org/r/20210107185316.788815-3-jaegeuk@kernel.org Fixes: 69a6c269c097 ("scsi: ufs: Use blk_{get,put}_request() to allocate and free TMFs") Reviewed-by: Can Guo cang@codeaurora.org Signed-off-by: Jaegeuk Kim jaegeuk@kernel.org Signed-off-by: Martin K. Petersen martin.petersen@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Orson Zhai orson.zhai@unisoc.com

---

drivers/scsi/ufs/ufshcd.c | 18 +++++++++++++----- 1 file changed, 13 insertions(+), 5 deletions(-)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index a5d4ee6..4004506 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -4748,7 +4748,8 @@ ufshcd_transfer_rsp_status(struct ufs_hba *hba, struct ufshcd_lrb *lrbp) break; } /* end of switch */

• if ((host_byte(result) != DID_OK) && !hba->silence_err_logs)

• if ((host_byte(result) != DID_OK) &&

•    (host_byte(result) != DID_REQUEUE) && !hba->silence_err_logs)
  

  ufshcd_print_trs(hba, 1 << lrbp->task_tag, true); return result;

} @@ -5661,9 +5662,13 @@ static irqreturn_t ufshcd_intr(int irq, void *__hba) intr_status = ufshcd_readl(hba, REG_INTERRUPT_STATUS); }

• if (enabled_intr_status && retval == IRQ_NONE) {

• dev_err(hba->dev, "%s: Unhandled interrupt 0x%08x\n",
  

• 			__func__, intr_status);
  

• if (enabled_intr_status && retval == IRQ_NONE &&

• 		!ufshcd_eh_in_progress(hba)) {
  

• dev_err(hba->dev, "%s: Unhandled interrupt 0x%08x (0x%08x, 0x%08x)\n",
  

• 			__func__,
  

• 			intr_status,
  

• 			hba->ufs_stats.last_intr_status,
  

• 			enabled_intr_status);
  

  ufshcd_dump_regs(hba, 0, UFSHCI_REG_SPACE_SIZE, "host_regs: "); }

@@ -5705,7 +5710,10 @@ static int __ufshcd_issue_tm_cmd(struct ufs_hba *hba, /* * blk_get_request() is used here only to get a free tag. */

• req = blk_get_request(q, REQ_OP_DRV_OUT, BLK_MQ_REQ_RESERVED);

• req = blk_get_request(q, REQ_OP_DRV_OUT, 0);
• if (IS_ERR(req))

• return PTR_ERR(req);
  

• req->end_io_data = &wait; ufshcd_hold(hba, false);

2.7.4

This commit does not build :(

Did you test it?

Please fix up and resend AFTER testing it.

thanks,

greg k-h