kernel/drivers/scsi/scsi_error.c, branch linux-6.9.y

scsi: core: Move scsi_host_busy() out of host lock if it is for per-command

2024-02-05T21:15:20Z

Commit 4373534a9850 ("scsi: core: Move scsi_host_busy() out of host lock for waking up EH handler") intended to fix a hard lockup issue triggered by EH. The core idea was to move scsi_host_busy() out of the host lock when processing individual commands for EH. However, a suggested style change inadvertently caused scsi_host_busy() to remain under the host lock. Fix this by calling scsi_host_busy() outside the lock. Fixes: 4373534a9850 ("scsi: core: Move scsi_host_busy() out of host lock for waking up EH handler") Cc: Sathya Prakash Veerichetty Cc: Bart Van Assche Cc: Ewan D. Milne Signed-off-by: Ming Lei Link: https://lore.kernel.org/r/20240203024521.2006455-1-ming.lei@redhat.com Reviewed-by: Bart Van Assche Signed-off-by: Martin K. Petersen

scsi: core: Move scsi_host_busy() out of host lock for waking up EH handler

2024-01-24T02:21:51Z

Inside scsi_eh_wakeup(), scsi_host_busy() is called & checked with host lock every time for deciding if error handler kthread needs to be waken up. This can be too heavy in case of recovery, such as: - N hardware queues - queue depth is M for each hardware queue - each scsi_host_busy() iterates over (N * M) tag/requests If recovery is triggered in case that all requests are in-flight, each scsi_eh_wakeup() is strictly serialized, when scsi_eh_wakeup() is called for the last in-flight request, scsi_host_busy() has been run for (N * M - 1) times, and request has been iterated for (N*M - 1) * (N * M) times. If both N and M are big enough, hard lockup can be triggered on acquiring host lock, and it is observed on mpi3mr(128 hw queues, queue depth 8169). Fix the issue by calling scsi_host_busy() outside the host lock. We don't need the host lock for getting busy count because host the lock never covers that. [mkp: Drop unnecessary 'busy' variables pointed out by Bart] Cc: Ewan Milne Fixes: 6eb045e092ef ("scsi: core: avoid host-wide host_busy counter for scsi_mq") Signed-off-by: Ming Lei Link: https://lore.kernel.org/r/20240112070000.4161982-1-ming.lei@redhat.com Reviewed-by: Ewan D. Milne Reviewed-by: Sathya Prakash Veerichetty Tested-by: Sathya Prakash Veerichetty Reviewed-by: Bart Van Assche Signed-off-by: Martin K. Petersen

Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

2024-01-20T17:42:32Z

Pull SCSI updates from James Bottomley: "Final round of fixes that came in too late to send in the first request. It's nine bug fixes and one version update (because of a bug fix) and one set of PCI ID additions. There's one bug fix in the core which is really a one liner (except that an additional sdev pointer was added for convenience) and the rest are in drivers" * tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: scsi: target: core: Add TMF to tmr_list handling scsi: core: Kick the requeue list after inserting when flushing scsi: fnic: unlock on error path in fnic_queuecommand() scsi: fcoe: Fix unsigned comparison with zero in store_ctlr_mode() scsi: mpi3mr: Fix mpi3mr_fw.c kernel-doc warnings scsi: smartpqi: Bump driver version to 2.1.26-030 scsi: smartpqi: Fix logical volume rescan race condition scsi: smartpqi: Add new controller PCI IDs scsi: ufs: qcom: Remove unnecessary goto statement from ufs_qcom_config_esi() scsi: ufs: core: Remove the ufshcd_hba_exit() call from ufshcd_async_scan() scsi: ufs: core: Simplify power management during async scan

scsi: core: Kick the requeue list after inserting when flushing

2024-01-12T02:37:43Z

When libata calls ata_link_abort() to abort all ata queued commands, it calls blk_abort_request() on the SCSI command representing each QC. This causes scsi_timeout() to be called, which calls scsi_eh_scmd_add() for each SCSI command. scsi_eh_scmd_add() sets the SCSI host to state recovery, and then adds the command to shost->eh_cmd_q. This will wake up the SCSI EH, and eventually the libata EH strategy handler will be called, which calls scsi_eh_flush_done_q() to either flush retry or flush finish each failed command. The commands that are flush retried by scsi_eh_flush_done_q() are done so using scsi_queue_insert(). Before commit 8b566edbdbfb ("scsi: core: Only kick the requeue list if necessary"), __scsi_queue_insert() called blk_mq_requeue_request() with the second argument set to true, indicating that it should always kick/run the requeue list after inserting. After commit 8b566edbdbfb ("scsi: core: Only kick the requeue list if necessary"), __scsi_queue_insert() does not kick/run the requeue list after inserting, if the current SCSI host state is recovery (which is the case in the libata example above). This optimization is probably fine in most cases, as I can only assume that most often someone will eventually kick/run the queues. However, that is not the case for scsi_eh_flush_done_q(), where we can see that the request gets inserted to the requeue list, but the queue is never started after the request has been inserted, leading to the block layer waiting for the completion of command that never gets to run. Since scsi_eh_flush_done_q() is called by SCSI EH context, the SCSI host state is most likely always in recovery when this function is called. Thus, let scsi_eh_flush_done_q() explicitly kick the requeue list after inserting a flush retry command, so that scsi_eh_flush_done_q() keeps the same behavior as before commit 8b566edbdbfb ("scsi: core: Only kick the requeue list if necessary"). Simple reproducer for the libata example above: $ hdparm -Y /dev/sda $ echo 1 > /sys/class/scsi_device/0\:0\:0\:0/device/delete Fixes: 8b566edbdbfb ("scsi: core: Only kick the requeue list if necessary") Reported-by: Kevin Locke Closes: https://lore.kernel.org/linux-scsi/ZZw3Th70wUUvCiCY@kevinlocke.name/ Signed-off-by: Niklas Cassel Link: https://lore.kernel.org/r/20240111120533.3612509-1-cassel@kernel.org Reviewed-by: Bart Van Assche Reviewed-by: Damien Le Moal Signed-off-by: Martin K. Petersen

Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

2024-01-11T22:24:32Z

Pull SCSI updates from James Bottomley: "Updates to the usual drivers (ufs, mpi3mr, mpt3sas, lpfc, fnic, hisi_sas, arcmsr, ) plus the usual assorted minor fixes and updates. This time around there's only a single line update to the core, so nothing major and barely anything minor" * tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (135 commits) scsi: ufs: core: Simplify ufshcd_auto_hibern8_update() scsi: ufs: core: Rename ufshcd_auto_hibern8_enable() and make it static scsi: ufs: qcom: Fix ESI vector mask scsi: ufs: host: Fix kernel-doc warning scsi: hisi_sas: Correct the number of global debugfs registers scsi: hisi_sas: Rollback some operations if FLR failed scsi: hisi_sas: Check before using pointer variables scsi: hisi_sas: Replace with standard error code return value scsi: hisi_sas: Set .phy_attached before notifing phyup event HISI_PHYE_PHY_UP_PM scsi: ufs: core: Add sysfs node for UFS RTC update scsi: ufs: core: Add UFS RTC support scsi: ufs: core: Add ufshcd_is_ufs_dev_busy() scsi: ufs: qcom: Remove unused definitions scsi: ufs: qcom: Use ufshcd_rmwl() where applicable scsi: ufs: qcom: Remove support for host controllers older than v2.0 scsi: ufs: qcom: Simplify ufs_qcom_{assert/deassert}_reset scsi: ufs: qcom: Initialize cycles_in_1us variable in ufs_qcom_set_core_clk_ctrl() scsi: ufs: qcom: Sort includes alphabetically scsi: ufs: qcom: Remove unused ufs_qcom_hosts struct array scsi: ufs: qcom: Use dev_err_probe() to simplify error handling of devm_gpiod_get_optional() ...

scsi: core: Always send batch on reset or error handling command

2023-12-19T02:09:41Z

In commit 8930a6c20791 ("scsi: core: add support for request batching") the block layer bd->last flag was mapped to SCMD_LAST and used as an indicator to send the batch for the drivers that implement this feature. However, the error handling code was not updated accordingly. scsi_send_eh_cmnd() is used to send error handling commands and request sense. The problem is that request sense comes as a single command that gets into the batch queue and times out. As a result the device goes offline after several failed resets. This was observed on virtio_scsi during a device resize operation. [ 496.316946] sd 0:0:4:0: [sdd] tag#117 scsi_eh_0: requesting sense [ 506.786356] sd 0:0:4:0: [sdd] tag#117 scsi_send_eh_cmnd timeleft: 0 [ 506.787981] sd 0:0:4:0: [sdd] tag#117 abort To fix this always set SCMD_LAST flag in scsi_send_eh_cmnd() and scsi_reset_ioctl(). Fixes: 8930a6c20791 ("scsi: core: add support for request batching") Cc: Signed-off-by: Alexander Atanasov Link: https://lore.kernel.org/r/20231215121008.2881653-1-alexander.atanasov@virtuozzo.com Reviewed-by: Ming Lei Signed-off-by: Martin K. Petersen

scsi: core: Add a precondition check in scsi_eh_scmd_add()

2023-11-25T00:23:44Z

Calling scsi_eh_scmd_add() may cause the error handler never to be woken up because this may result in shost->host_failed to become larger than scsi_host_busy(shost). Hence complain if scsi_eh_scmd_add() is called after SCMD_STATE_INFLIGHT has been cleared. Cc: Hannes Reinecke Cc: Damien Le Moal Cc: Mike Christie Cc: John Garry Cc: Ming Lei Signed-off-by: Bart Van Assche Link: https://lore.kernel.org/r/20231115193343.2262013-1-bvanassche@acm.org Signed-off-by: Martin K. Petersen

scsi: sd: Handle read/write CDL timeout failures

2023-05-22T21:05:19Z

Commands using a duration limit descriptor that has limit policies set to a value other than 0x0 may be failed by the device if one of the limits are exceeded. For such commands, since the failure is the result of the user duration limit configuration and workload, the commands should not be retried and terminated immediately. Furthermore, to allow the user to differentiate these "soft" failures from hard errors due to hardware problem, a different error code than EIO should be returned. There are 2 cases to consider: (1) The failure is due to a limit policy failing the command with a check condition sense key, that is, any limit policy other than 0xD. For this case, scsi_check_sense() is modified to detect failures with the ABORTED COMMAND sense key and the COMMAND TIMEOUT BEFORE PROCESSING or COMMAND TIMEOUT DURING PROCESSING or COMMAND TIMEOUT DURING PROCESSING DUE TO ERROR RECOVERY additional sense code. For these failures, a SUCCESS disposition is returned so that scsi_finish_command() is called to terminate the command. (2) The failure is due to a limit policy set to 0xD, which result in the command being terminated with a GOOD status, COMPLETED sense key, and DATA CURRENTLY UNAVAILABLE additional sense code. To handle this case, the scsi_check_sense() is modified to return a SUCCESS disposition so that scsi_finish_command() is called to terminate the command. In addition, scsi_decide_disposition() has to be modified to see if a command being terminated with GOOD status has sense data. This is as defined in SCSI Primary Commands - 6 (SPC-6), so all according to spec, even if GOOD status commands were not checked before. If scsi_check_sense() detects sense data representing a duration limit, scsi_check_sense() will set the newly introduced SCSI ML byte SCSIML_STAT_DL_TIMEOUT. This SCSI ML byte is checked in scsi_noretry_cmd(), so that a command that failed because of a CDL timeout cannot be retried. The SCSI ML byte is also checked in scsi_result_to_blk_status() to complete the command request with the BLK_STS_DURATION_LIMIT status, which result in the user seeing ETIME errors for the failed commands. Co-developed-by: Damien Le Moal Signed-off-by: Damien Le Moal Reviewed-by: Hannes Reinecke Signed-off-by: Niklas Cassel Link: https://lore.kernel.org/r/20230511011356.227789-12-nks@flawful.org Signed-off-by: Martin K. Petersen

scsi: core: Allow libata to complete successful commands via EH

2023-05-22T21:05:18Z

In SCSI, we get the sense data as part of the completion, for ATA however, we need to fetch the sense data as an extra step. For an aborted ATA command the sense data is fetched via libata's ->eh_strategy_handler(). For Command Duration Limits policy 0xD: The device shall complete the command without error with the additional sense code set to DATA CURRENTLY UNAVAILABLE. In order to handle this policy in libata, we intend to send a successful command via SCSI EH, and let libata's ->eh_strategy_handler() fetch the sense data for the good command. This is similar to how we handle an aborted ATA command, just that we need to read the Successful NCQ Commands log instead of the NCQ Command Error log. When we get a SATA completion with successful commands, ATA_SENSE will be set, indicating that some commands in the completion have sense data. The sense_valid bitmask in the Sense Data for Successful NCQ Commands log will inform exactly which commands that had sense data, which might be a subset of all the commands that was completed in the same completion. (Yet all will have ATA_SENSE set, since the status is per completion.) The successful commands that have e.g. a "DATA CURRENTLY UNAVAILABLE" sense data will have a SCSI ML byte set, so scsi_eh_flush_done_q() will not set the scmd->result to DID_TIME_OUT for these commands. However, the successful commands that did not have sense data, must not get their result marked as DID_TIME_OUT by SCSI EH. Add a new flag SCMD_FORCE_EH_SUCCESS, which tells SCSI EH to not mark a command as DID_TIME_OUT, even if it has scmd->result == SAM_STAT_GOOD. This will be used by libata in a subsequent commit. Reviewed-by: Christoph Hellwig Reviewed-by: Hannes Reinecke Signed-off-by: Niklas Cassel Link: https://lore.kernel.org/r/20230511011356.227789-5-nks@flawful.org Signed-off-by: Martin K. Petersen

scsi: core: Declare most SCSI host template pointers const

2023-03-24T23:19:19Z

Prepare for constifying most SCSI host template pointers by constifying the SCSI host template pointer arguments and variables in the SCSI core. Reviewed-by: Benjamin Block Reviewed-by: John Garry Reviewed-by: Ming Lei Cc: Christoph Hellwig Cc: Hannes Reinecke Cc: Mike Christie Signed-off-by: Bart Van Assche Link: https://lore.kernel.org/r/20230322195515.1267197-3-bvanassche@acm.org Signed-off-by: Martin K. Petersen