Skip to content

Commit

Permalink
qla2xxx: avoid maybe_uninitialized warning
Browse files Browse the repository at this point in the history
The qlt_check_reserve_free_req() function produces an incorrect warning
when CONFIG_PROFILE_ANNOTATED_BRANCHES is set:

drivers/scsi/qla2xxx/qla_target.c: In function 'qlt_check_reserve_free_req':
drivers/scsi/qla2xxx/qla_target.c:1887:3: error: 'cnt_in' may be used uninitialized in this function [-Werror=maybe-uninitialized]
   ql_dbg(ql_dbg_io, vha, 0x305a,
   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
       "qla_target(%d): There is no room in the request ring: vha->req->ring_index=%d, vha->req->cnt=%d, req_cnt=%d Req-out=%d Req-in=%d Req-Length=%d\n",
       ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
       vha->vp_idx, vha->req->ring_index,
       ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
       vha->req->cnt, req_cnt, cnt, cnt_in, vha->req->length);
       ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/scsi/qla2xxx/qla_target.c:1887:3: error: 'cnt' may be used uninitialized in this function [-Werror=maybe-uninitialized]

The problem is that gcc fails to track the state of the condition across
an annotated branch.

This slightly rearranges the code to move the second if() block
into the first one, to avoid the warning while retaining the
behavior of the code.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-By: Himanshu Madhani <himanshu.madhani@qlogic.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
  • Loading branch information
Arnd Bergmann authored and Martin K. Petersen committed Mar 18, 2016
1 parent 3deb943 commit bc7095a
Showing 1 changed file with 9 additions and 7 deletions.
16 changes: 9 additions & 7 deletions drivers/scsi/qla2xxx/qla_target.c
Original file line number Diff line number Diff line change
Expand Up @@ -1872,15 +1872,17 @@ static int qlt_check_reserve_free_req(struct scsi_qla_host *vha,
else
vha->req->cnt = vha->req->length -
(vha->req->ring_index - cnt);
}

if (unlikely(vha->req->cnt < (req_cnt + 2))) {
ql_dbg(ql_dbg_io, vha, 0x305a,
"qla_target(%d): There is no room in the request ring: vha->req->ring_index=%d, vha->req->cnt=%d, req_cnt=%d Req-out=%d Req-in=%d Req-Length=%d\n",
vha->vp_idx, vha->req->ring_index,
vha->req->cnt, req_cnt, cnt, cnt_in, vha->req->length);
return -EAGAIN;
if (unlikely(vha->req->cnt < (req_cnt + 2))) {
ql_dbg(ql_dbg_io, vha, 0x305a,
"qla_target(%d): There is no room in the request ring: vha->req->ring_index=%d, vha->req->cnt=%d, req_cnt=%d Req-out=%d Req-in=%d Req-Length=%d\n",
vha->vp_idx, vha->req->ring_index,
vha->req->cnt, req_cnt, cnt, cnt_in,
vha->req->length);
return -EAGAIN;
}
}

vha->req->cnt -= req_cnt;

return 0;
Expand Down

0 comments on commit bc7095a

Please sign in to comment.