nvme-fc: avoid gcc-10 zero-length-bounds warning

When CONFIG_ARCH_NO_SG_CHAIN is set, op->sgl[0] cannot be dereferenced,
as gcc-10 now points out:

drivers/nvme/host/fc.c: In function 'nvme_fc_init_request':
drivers/nvme/host/fc.c:1774:29: warning: array subscript 0 is outside the bounds of an interior zero-length array 'struct scatterlist[0]' [-Wzero-length-bounds]
 1774 |  op->op.fcp_req.first_sgl = &op->sgl[0];
      |                             ^~~~~~~~~~~
drivers/nvme/host/fc.c:98:21: note: while referencing 'sgl'
   98 |  struct scatterlist sgl[NVME_INLINE_SG_CNT];
      |                     ^~~

I don't know if this is a legitimate warning or a false-positive.
If this is just a false alarm, the warning is easily suppressed
by interpreting the array as a pointer.

Fixes: b1ae1a2389 ("nvme-fc: Avoid preallocating big SGL for data")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Arnd Bergmann 2020-04-30 23:30:57 +02:00 committed by Jens Axboe
parent e8cd1ff11d
commit 3add1d93d9
1 changed files with 1 additions and 1 deletions

View File

@ -2106,7 +2106,7 @@ nvme_fc_init_request(struct blk_mq_tag_set *set, struct request *rq,
res = __nvme_fc_init_request(ctrl, queue, &op->op, rq, queue->rqcnt++);
if (res)
return res;
op->op.fcp_req.first_sgl = &op->sgl[0];
op->op.fcp_req.first_sgl = op->sgl;
op->op.fcp_req.private = &op->priv[0];
nvme_req(rq)->ctrl = &ctrl->ctrl;
return res;