linux-kernel - [PATCH] scsi: core: Do not retry I/Os during depopulation

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <20250130222632.1462218-1-ipylypiv@google.com>
Date: Thu, 30 Jan 2025 14:26:31 -0800
From: Igor Pylypiv <ipylypiv@...gle.com>
To: "James E.J. Bottomley" <James.Bottomley@...senPartnership.com>, 
	"Martin K. Petersen" <martin.petersen@...cle.com>
Cc: Douglas Gilbert <dgilbert@...erlog.com>, linux-scsi@...r.kernel.org, 
	linux-kernel@...r.kernel.org, Igor Pylypiv <ipylypiv@...gle.com>
Subject: [PATCH] scsi: core: Do not retry I/Os during depopulation

Fail I/Os instead of retry to prevent user space processes from being
blocked on the I/O completion for several minutes.

Retrying I/Os during "depopulation in progress" or "depopulation restore
in progress" results in a continuous retry loop until the depopulation
completes or until the I/O retry loop is aborted due to a timeout by
the scsi_cmd_runtime_exceeced().

Depopulation is slow and can take 24+ hours to complete on 20+ TB HDDs.
Most I/Os in the depopulation retry loop end up taking several minutes
before returning the failure to user space.

Signed-off-by: Igor Pylypiv <ipylypiv@...gle.com>
---
 drivers/scsi/scsi_lib.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index e7ea1f04164a..3ab4c958da45 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -872,13 +872,18 @@ static void scsi_io_completion_action(struct scsi_cmnd *cmd, int result)
 				case 0x1a: /* start stop unit in progress */
 				case 0x1b: /* sanitize in progress */
 				case 0x1d: /* configuration in progress */
-				case 0x24: /* depopulation in progress */
-				case 0x25: /* depopulation restore in progress */
 					action = ACTION_DELAYED_RETRY;
 					break;
 				case 0x0a: /* ALUA state transition */
 					action = ACTION_DELAYED_REPREP;
 					break;
+				/*
+				 * Depopulation might take many hours,
+				 * thus it is not worthwhile to retry.
+				 */
+				case 0x24: /* depopulation in progress */
+				case 0x25: /* depopulation restore in progress */
+					fallthrough;
 				default:
 					action = ACTION_FAIL;
 					break;
-- 
2.48.1.362.g079036d154-goog