blob: 7cade0a11b64d390b0705986f67fbd9399c5c507 [file] [log] [blame]
From 32f0d4debc451acd9e9acc6fb16578a96f865286 Mon Sep 17 00:00:00 2001
From: Damien Le Moal <>
Date: Tue, 1 Oct 2019 16:48:39 +0900
Subject: [PATCH] scsi: core: save/restore command resid for error handling
commit 8f8fed0cdbbd6cdbf28d9ebe662f45765d2f7d39 upstream.
When a non-passthrough command is terminated with CHECK CONDITION, request
sense is executed by hijacking the command descriptor. Since
scsi_eh_prep_cmnd() and scsi_eh_restore_cmnd() do not save/restore the
original command resid, the value returned on failure of the original
command is lost and replaced with the value set by the execution of the
request sense command. This value may in many instances be unaligned to the
device sector size, causing sd_done() to print a warning message about the
incorrect unaligned resid before the command is retried.
Fix this problem by saving the original command residual in struct
scsi_eh_save using scsi_eh_prep_cmnd() and restoring it in
scsi_eh_restore_cmnd(). In addition, to make sure that the request sense
command is executed with a correctly initialized command structure, also
reset the residual to 0 in scsi_eh_prep_cmnd() after saving the original
command value in struct scsi_eh_save.
Signed-off-by: Damien Le Moal <>
Reviewed-by: Bart Van Assche <>
Signed-off-by: Martin K. Petersen <>
Signed-off-by: Paul Gortmaker <>
diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c
index bfa569facd5b..ecfc528d54cd 100644
--- a/drivers/scsi/scsi_error.c
+++ b/drivers/scsi/scsi_error.c
@@ -967,6 +967,7 @@ void scsi_eh_prep_cmnd(struct scsi_cmnd *scmd, struct scsi_eh_save *ses,
ses->data_direction = scmd->sc_data_direction;
ses->sdb = scmd->sdb;
ses->result = scmd->result;
+ ses->resid_len = scmd->req.resid_len;
ses->underflow = scmd->underflow;
ses->prot_op = scmd->prot_op;
ses->eh_eflags = scmd->eh_eflags;
@@ -977,6 +978,7 @@ void scsi_eh_prep_cmnd(struct scsi_cmnd *scmd, struct scsi_eh_save *ses,
memset(scmd->cmnd, 0, BLK_MAX_CDB);
memset(&scmd->sdb, 0, sizeof(scmd->sdb));
scmd->result = 0;
+ scmd->req.resid_len = 0;
if (sense_bytes) {
scmd->sdb.length = min_t(unsigned, SCSI_SENSE_BUFFERSIZE,
@@ -1029,6 +1031,7 @@ void scsi_eh_restore_cmnd(struct scsi_cmnd* scmd, struct scsi_eh_save *ses)
scmd->sc_data_direction = ses->data_direction;
scmd->sdb = ses->sdb;
scmd->result = ses->result;
+ scmd->req.resid_len = ses->resid_len;
scmd->underflow = ses->underflow;
scmd->prot_op = ses->prot_op;
scmd->eh_eflags = ses->eh_eflags;
diff --git a/include/scsi/scsi_eh.h b/include/scsi/scsi_eh.h
index 3810b340551c..6bd5ed695a5e 100644
--- a/include/scsi/scsi_eh.h
+++ b/include/scsi/scsi_eh.h
@@ -32,6 +32,7 @@ extern int scsi_ioctl_reset(struct scsi_device *, int __user *);
struct scsi_eh_save {
/* saved state */
int result;
+ unsigned int resid_len;
int eh_eflags;
enum dma_data_direction data_direction;
unsigned underflow;