iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

scsi: Fix a harmless double shift bug

Browse Source 
Smatch generates a warning:

    drivers/scsi/scsi_lib.c:1656 scsi_mq_done() warn: test_bit() takes a bit number

The problem is that SCMD_STATE_COMPLETE is supposed to be bit number 0
and not a mask like "(1 << 0)".  It is used like this:

        if (test_and_set_bit(SCMD_STATE_COMPLETE, &scmd->state))

The test_and_set_bit() has a shift built in so it's a double left shift
and uses bit number 1 instead of number 0.  This bug is harmless because
it's done consistently and it doesn't clash with any other flags.

Fixes: f1342709d18a ("scsi: Do not rely on blk-mq for double completions")
Reviewed-by: Keith Busch <keith.busch@intel.com>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Dan Carpenter 2018-12-07 22:06:12 -07:00 committed by Jens Axboe
parent 3236b458c4
commit 29cadd2bb6
1 changed files with 1 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
include/scsi/scsi_cmnd.h
View File

@ -62,7 +62,7 @@ struct scsi_pointer {
#define SCMD_PRESERVED_FLAGS (SCMD_UNCHECKED_ISA_DMA | SCMD_INITIALIZED)
/* for scmd->state */
#define SCMD_STATE_COMPLETE (1 << 0)
#define SCMD_STATE_COMPLETE 0
struct scsi_cmnd {
struct scsi_request req;