kernel/linux.git/drivers/scsi/scsi_error.c, branch v6.19.11

scsi: core: Wake up the error handler when final completions race against each other

2026-01-17T03:54:27+00:00

The fragile ordering between marking commands completed or failed so that the error handler only wakes when the last running command completes or times out has race conditions. These race conditions can cause the SCSI layer to fail to wake the error handler, leaving I/O through the SCSI host stuck as the error state cannot advance. First, there is an memory ordering issue within scsi_dec_host_busy(). The write which clears SCMD_STATE_INFLIGHT may be reordered with reads counting in scsi_host_busy(). While the local CPU will see its own write, reordering can allow other CPUs in scsi_dec_host_busy() or scsi_eh_inc_host_failed() to see a raised busy count, causing no CPU to see a host busy equal to the host_failed count. This race condition can be prevented with a memory barrier on the error path to force the write to be visible before counting host busy commands. Second, there is a general ordering issue with scsi_eh_inc_host_failed(). By counting busy commands before incrementing host_failed, it can race with a final command in scsi_dec_host_busy(), such that scsi_dec_host_busy() does not see host_failed incremented but scsi_eh_inc_host_failed() counts busy commands before SCMD_STATE_INFLIGHT is cleared by scsi_dec_host_busy(), resulting in neither waking the error handler task. This needs the call to scsi_host_busy() to be moved after host_failed is incremented to close the race condition. Fixes: 6eb045e092ef ("scsi: core: avoid host-wide host_busy counter for scsi_mq") Signed-off-by: David Jeffery Reviewed-by: Bart Van Assche Link: https://patch.msgid.link/20260113161036.6730-1-djeffery@redhat.com Signed-off-by: Martin K. Petersen

scsi: core: Fix error handler encryption support

2026-01-04T20:16:20+00:00

Some low-level drivers (LLD) access block layer crypto fields, such as rq->crypt_keyslot and rq->crypt_ctx within `struct request`, to configure hardware for inline encryption. However, SCSI Error Handling (EH) commands (e.g., TEST UNIT READY, START STOP UNIT) should not involve any encryption setup. To prevent drivers from erroneously applying crypto settings during EH, this patch saves the original values of rq->crypt_keyslot and rq->crypt_ctx before an EH command is prepared via scsi_eh_prep_cmnd(). These fields in the 'struct request' are then set to NULL. The original values are restored in scsi_eh_restore_cmnd() after the EH command completes. This ensures that the block layer crypto context does not leak into EH command execution. Signed-off-by: Brian Kao Link: https://patch.msgid.link/20251218031726.2642834-1-powenkao@google.com Cc: stable@vger.kernel.org Reviewed-by: Bart Van Assche Signed-off-by: Martin K. Petersen

Merge branch 6.18/scsi-fixes into 6.19/scsi-staging

2025-11-20T03:59:25+00:00

Pull in fixes branch to resolve UFS merge conflict. Signed-off-by: Martin K. Petersen

scsi: core: Make the budget map optional

2025-11-12T22:02:31+00:00

Prepare for not allocating a budget map for pseudo SCSI devices by checking whether a budget map has been allocated before using it. Reviewed-by: Hannes Reinecke Cc: John Garry Cc: Ming Lei Signed-off-by: Bart Van Assche Link: https://patch.msgid.link/20251031204029.2883185-4-bvanassche@acm.org Signed-off-by: Martin K. Petersen

scsi: core: Fix the unit attention counter implementation

2025-10-22T01:09:36+00:00

scsi_decide_disposition() may call scsi_check_sense(). scsi_decide_disposition() calls are not serialized. Hence, counter updates by scsi_check_sense() must be serialized. Hence this patch that makes the counters updated by scsi_check_sense() atomic. Cc: Kai Mäkisara Fixes: a5d518cd4e3e ("scsi: core: Add counters for New Media and Power On/Reset UNIT ATTENTIONs") Signed-off-by: Bart Van Assche Reviewed-by: Ewan D. Milne Link: https://patch.msgid.link/20251014220244.3689508-1-bvanassche@acm.org Signed-off-by: Martin K. Petersen

scsi: error: alua: I/O errors for ALUA state transitions

2025-06-10T02:02:13+00:00

When a host is configured with a few LUNs and I/O is running, injecting FC faults repeatedly leads to path recovery problems. The LUNs have 4 paths each and 3 of them come back active after say an FC fault which makes 2 of the paths go down, instead of all 4. This happens after several iterations of continuous FC faults. Reason here is that we're returning an I/O error whenever we're encountering sense code 06/04/0a (LOGICAL UNIT NOT ACCESSIBLE, ASYMMETRIC ACCESS STATE TRANSITION) instead of retrying. Signed-off-by: Rajashekhar M A Signed-off-by: Hannes Reinecke Link: https://lore.kernel.org/r/20250606135924.27397-1-hare@kernel.org Reviewed-by: Lee Duncan Signed-off-by: Martin K. Petersen

scsi: scsi_error: Add comments to scsi_check_sense()

2025-03-04T03:11:47+00:00

Add a comment block describing the COMPLETED case with ASC/ASCQ 0x55/0xA to mention that it relates to command duration limits very special policy 0xD command completion. Signed-off-by: Damien Le Moal Link: https://lore.kernel.org/r/20250228031751.12083-1-dlemoal@kernel.org Signed-off-by: Martin K. Petersen

scsi: core: Add counters for New Media and Power On/Reset UNIT ATTENTIONs

2025-02-03T22:43:31+00:00

The purpose of the counters is to enable all ULDs attached to a device to find out that a New Media or/and Power On/Reset Unit Attentions has/have been set, even if another ULD catches the Unit Attention as response to a SCSI command. The ULDs can read the counters and see if the values have changed from the previous check. Signed-off-by: Kai Mäkisara Link: https://lore.kernel.org/r/20250120194925.44432-3-Kai.Makisara@kolumbus.fi Reviewed-by: John Meneghini Tested-by: John Meneghini Signed-off-by: Martin K. Petersen

scsi: scsi_error: Add kernel-doc for exported functions

2025-01-10T20:15:02+00:00

Convert scsi_report_bus_reset() and scsi_report_device_reset() to kernel-doc since they are exported. This allows them to be part of the driver-api/scsi.rst docbook. Signed-off-by: Randy Dunlap Link: https://lore.kernel.org/r/20241212205217.597844-2-rdunlap@infradead.org CC: James E.J. Bottomley CC: Martin K. Petersen Signed-off-by: Martin K. Petersen

move asm/unaligned.h to linux/unaligned.h

2024-10-02T21:23:23+00:00

asm/unaligned.h is always an include of asm-generic/unaligned.h; might as well move that thing to linux/unaligned.h and include that - there's nothing arch-specific in that header. auto-generated by the following: for i in `git grep -l -w asm/unaligned.h`; do sed -i -e "s/asm\/unaligned.h/linux\/unaligned.h/" $i done for i in `git grep -l -w asm-generic/unaligned.h`; do sed -i -e "s/asm-generic\/unaligned.h/linux\/unaligned.h/" $i done git mv include/asm-generic/unaligned.h include/linux/unaligned.h git mv tools/include/asm-generic/unaligned.h tools/include/linux/unaligned.h sed -i -e "/unaligned.h/d" include/asm-generic/Kbuild sed -i -e "s/__ASM_GENERIC/__LINUX/" include/linux/unaligned.h tools/include/linux/unaligned.h