Re: [PATCH 3/4] scsi: qla2xxx: avoid printf format warning

[Himanshu Madhani <hmadhani@marvell.com>]

On 3/4/19, 11:39 AM, "Arnd Bergmann" <arnd@arndb.de> wrote:

    Depending on the target architecture and configuration, both phys_addr_t
    and dma_addr_t may be smaller than 'long long', so we get a warning when
    printing either of them using the %llx format string:
    
    drivers/scsi/qla2xxx/qla_iocb.c: In function 'qla24xx_walk_and_build_prot_sglist':
    drivers/scsi/qla2xxx/qla_iocb.c:1140:46: error: format '%llx' expects argument of type 'long long unsigned int', but argument 6 has type 'dma_addr_t' {aka 'unsigned int'} [-Werror=format=]
             "%s: page boundary crossing (phys=%llx len=%x)\n",
                                               ~~~^
                                               %x
             __func__, sle_phys, sg->length);
                       ~~~~~~~~
    drivers/scsi/qla2xxx/qla_iocb.c:1180:29: error: format '%llx' expects argument of type 'long long unsigned int', but argument 7 has type 'dma_addr_t' {aka 'unsigned int'} [-Werror=format=]
            "%s: sg[%x] (phys=%llx sglen=%x) ldma_sg_len: %x dif_bundl_len: %x ldma_needed: %x\n",
                              ~~~^
    
    There are special %pad and %pap format strings in Linux that we could use here,
    but since the driver already does 64-bit arithmetic on the values, using a
    plain 'u64' seems more consistent here.
    
    Note: A possible related issue may be that the driver possibly checks the
    wrong kind of overflow: when an IOMMU is in use, buffers that cross a 32-bit
    boundary in physical addresses would still be mapped into dma addresses
    within the low 4GB space, so I suspect that we actually want to check
    sg_dma_address() instead of sg_phys() here.
    
    Fixes: 50b812755e97 ("scsi: qla2xxx: Fix DMA error when the DIF sg buffer crosses 4GB boundary")
    Signed-off-by: Arnd Bergmann <arnd@arndb.de>
    ---
     drivers/scsi/qla2xxx/qla_iocb.c | 4 ++--
     1 file changed, 2 insertions(+), 2 deletions(-)
    
    diff --git a/drivers/scsi/qla2xxx/qla_iocb.c b/drivers/scsi/qla2xxx/qla_iocb.c
    index 63f8e3c19841..456a41d2e2c6 100644
    --- a/drivers/scsi/qla2xxx/qla_iocb.c
    +++ b/drivers/scsi/qla2xxx/qla_iocb.c
    @@ -1132,7 +1132,7 @@ qla24xx_walk_and_build_prot_sglist(struct qla_hw_data *ha, srb_t *sp,
     	/* if initiator doing write or target doing read */
     	if (direction_to_device) {
     		for_each_sg(sgl, sg, tot_dsds, i) {
    -			dma_addr_t sle_phys = sg_phys(sg);
    +			u64 sle_phys = sg_phys(sg);
     
     			/* If SGE addr + len flips bits in upper 32-bits */
     			if (MSD(sle_phys + sg->length) ^ MSD(sle_phys)) {
    @@ -1178,7 +1178,7 @@ qla24xx_walk_and_build_prot_sglist(struct qla_hw_data *ha, srb_t *sp,
     
     			ql_dbg(ql_dbg_tgt + ql_dbg_verbose, vha, 0xe023,
     			    "%s: sg[%x] (phys=%llx sglen=%x) ldma_sg_len: %x dif_bundl_len: %x ldma_needed: %x\n",
    -			    __func__, i, sg_phys(sg), sglen, ldma_sg_len,
    +			    __func__, i, (u64)sg_phys(sg), sglen, ldma_sg_len,
     			    difctx->dif_bundl_len, ldma_needed);
     
     			while (sglen) {
    -- 
    2.20.0
    
Looks good

Acked-by: Himanshu Madhani <hmadhani@marvell.com>