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scsi: ufs: core: Remove completed-without-interrupt path in ufshcd_abort()

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In SDB mode, a command that times out right as the controller finishes it
can be completed twice:

 1. The command times out and scsi_timeout() schedules ufshcd_abort().

 2. The controller finishes the command and clears its doorbell bit in
    REG_UTP_TRANSFER_REQ_DOOR_BELL, while the completion handler has not
    yet cleared BIT(tag) in hba->outstanding_reqs.

 3. ufshcd_abort() sees the doorbell bit clear and calls
    __ufshcd_transfer_req_compl() without clearing BIT(tag) in
    hba->outstanding_reqs.

 4. The normal completion handler or the logical unit reset that follows
    sees BIT(tag) still set in hba->outstanding_reqs and completes the same
    command a second time.

This branch only exists for a rare corner case, a completion interrupt that
is lost or arrives late. Remove it to simplify the abort path and leave
such a command to the SCSI error handler, like any other command that
cannot be aborted. The cost is a slower recovery in this corner case, which
is acceptable since it only happens after a timeout.

Fixes: 169f5eb288 ("scsi: ufs: Optimize SCSI command processing")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/fdb5c391-01ef-4a23-94c2-4f3853909348@acm.org
Signed-off-by: Stanley Jhu <stanleyjhu@google.com>
Reviewed-by: Peter Wang <peter.wang@mediatek.com>
Reviewed-by: Bean Huo <beanhuo@micron.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Link: https://patch.msgid.link/20261022034443.3034432-6-stanleyjhu@google.com
Signed-off-by: Martin K. Petersen (Oracle) <mkp@kernel.org>
This commit is contained in:
Stanley Jhu 2026-10-22 11:44:42 +08:00 committed by Martin K. Petersen (Oracle)
parent 3a7e551ae4
commit 7cfdfdd655
1 changed files with 0 additions and 9 deletions
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9
drivers/ufs/core/ufshcd.c
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@ -8125,15 +8125,6 @@ static int ufshcd_abort(struct scsi_cmnd *cmd)
}
hba->req_abort_count++;
if (!hba->mcq_enabled && !(reg & (1 << tag))) {
/* only execute this code in single doorbell mode */
dev_err(hba->dev,
"%s: cmd was completed, but without a notifying intr, tag = %d",
__func__, tag);
__ufshcd_transfer_req_compl(hba, 1UL << tag);
goto release;
}
/*
* Task abort to the device W-LUN is illegal. When this command
* will fail, due to spec violation, scsi err handling next step