Re: [PATCH] scsi: remove superfluous NULL pointer check from scsi_kill_request()

Re: [PATCH] scsi: remove superfluous NULL pointer check from scsi_kill_request()

[Joe Perches]

On Sun, 2009-07-26 at 16:29 +0200, Bartlomiej Zolnierkiewicz wrote:
> From: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
> Subject: [PATCH] scsi: remove superfluous NULL pointer check from scsi_kill_request()
> 
> >From Dan's list:
> 
> drivers/scsi/scsi_lib.c +1365 scsi_kill_request(9) warning: variable derefenced in initializer 'cmd'
> drivers/scsi/scsi_lib.c +1365 scsi_kill_request(9) warning: variable derefenced before check 'cmd'
> 
> We dereference cmd (and possible OOPS if cmd == NULL) before starting
> the request so just remove the superfluous debugging code altogether.
> 
> Reported-by: Dan Carpenter <error27@gmail.com>
> Cc: corbet@lwn.net
> Cc: eteo@redhat.com
> Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
> ---
>  drivers/scsi/scsi_lib.c |    6 ------
>  1 file changed, 6 deletions(-)
> 
> Index: b/drivers/scsi/scsi_lib.c
> ===================================================================
> --- a/drivers/scsi/scsi_lib.c
> +++ b/drivers/scsi/scsi_lib.c
> @@ -1365,12 +1365,6 @@ static void scsi_kill_request(struct req
>  
>  	blk_start_request(req);
>  
> -	if (unlikely(cmd == NULL)) {
> -		printk(KERN_CRIT "impossible request in %s.\n",
> -				 __func__);
> -		BUG();
> -	}
> -
>  	scsi_init_cmd_errh(cmd);
>  	cmd->result = DID_NO_CONNECT << 16;
>  	atomic_inc(&cmd->device->iorequest_cnt);
> --
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Re: [PATCH] scsi: remove superfluous NULL pointer check from scsi_kill_request()

[Joe Perches]

On Sat, 2009-07-25 at 08:42 -0700, Joe Perches wrote:
> On Sun, 2009-07-26 at 16:29 +0200, Bartlomiej Zolnierkiewicz wrote:
> > From: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Apologies for the empty message.  I was attempting
to tell Bartomiej his computer time is off but had
one too many keys pressed and the message got sent
to all before editing.

[PATCH] scsi: remove superfluous NULL pointer check from scsi_kill_request()

[Bartlomiej Zolnierkiewicz]

From: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Subject: [PATCH] scsi: remove superfluous NULL pointer check from scsi_kill_request()

>From Dan's list:

drivers/scsi/scsi_lib.c +1365 scsi_kill_request(9) warning: variable derefenced in initializer 'cmd'
drivers/scsi/scsi_lib.c +1365 scsi_kill_request(9) warning: variable derefenced before check 'cmd'

We dereference cmd (and possible OOPS if cmd == NULL) before starting
the request so just remove the superfluous debugging code altogether.

Reported-by: Dan Carpenter <error27@gmail.com>
Cc: corbet@lwn.net
Cc: eteo@redhat.com
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
---
 drivers/scsi/scsi_lib.c |    6 ------
 1 file changed, 6 deletions(-)

Index: b/drivers/scsi/scsi_lib.c
===================================================================
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -1365,12 +1365,6 @@ static void scsi_kill_request(struct req
 
 	blk_start_request(req);
 
-	if (unlikely(cmd == NULL)) {
-		printk(KERN_CRIT "impossible request in %s.\n",
-				 __func__);
-		BUG();
-	}
-
 	scsi_init_cmd_errh(cmd);
 	cmd->result = DID_NO_CONNECT << 16;
 	atomic_inc(&cmd->device->iorequest_cnt);