Re: [PATCH 01/11] block: nvme-scsi: Fix probable mask then right shift defects

From: Verma, Vishal L
Date: Mon Nov 10 2014 - 14:34:29 EST


On Sun, 2014-10-26 at 22:24 -0700, Joe Perches wrote:
> Precedence of & and >> is not the same and is not left to right.
> shift has higher precedence and should be done after the mask.
>
> Add parentheses around the mask.
>
> Signed-off-by: Joe Perches <joe@xxxxxxxxxxx>

Acked-by: Vishal Verma <vishal.l.verma@xxxxxxxxxxxxxxx>

> ---
> drivers/block/nvme-scsi.c | 12 ++++++------
> 1 file changed, 6 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/block/nvme-scsi.c b/drivers/block/nvme-scsi.c
> index a4cd6d6..529ee54 100644
> --- a/drivers/block/nvme-scsi.c
> +++ b/drivers/block/nvme-scsi.c
> @@ -1972,8 +1972,8 @@ static inline void nvme_trans_get_io_cdb10(u8 *cmd,
> {
> cdb_info->fua = GET_U8_FROM_CDB(cmd, IO_10_CDB_FUA_OFFSET) &
> IO_CDB_FUA_MASK;
> - cdb_info->prot_info = GET_U8_FROM_CDB(cmd, IO_10_CDB_WP_OFFSET) &
> - IO_CDB_WP_MASK >> IO_CDB_WP_SHIFT;
> + cdb_info->prot_info = (GET_U8_FROM_CDB(cmd, IO_10_CDB_WP_OFFSET) &
> + IO_CDB_WP_MASK) >> IO_CDB_WP_SHIFT;
> cdb_info->lba = GET_U32_FROM_CDB(cmd, IO_10_CDB_LBA_OFFSET);
> cdb_info->xfer_len = GET_U16_FROM_CDB(cmd, IO_10_CDB_TX_LEN_OFFSET);
> }
> @@ -1983,8 +1983,8 @@ static inline void nvme_trans_get_io_cdb12(u8 *cmd,
> {
> cdb_info->fua = GET_U8_FROM_CDB(cmd, IO_12_CDB_FUA_OFFSET) &
> IO_CDB_FUA_MASK;
> - cdb_info->prot_info = GET_U8_FROM_CDB(cmd, IO_12_CDB_WP_OFFSET) &
> - IO_CDB_WP_MASK >> IO_CDB_WP_SHIFT;
> + cdb_info->prot_info = (GET_U8_FROM_CDB(cmd, IO_12_CDB_WP_OFFSET) &
> + IO_CDB_WP_MASK) >> IO_CDB_WP_SHIFT;
> cdb_info->lba = GET_U32_FROM_CDB(cmd, IO_12_CDB_LBA_OFFSET);
> cdb_info->xfer_len = GET_U32_FROM_CDB(cmd, IO_12_CDB_TX_LEN_OFFSET);
> }
> @@ -1994,8 +1994,8 @@ static inline void nvme_trans_get_io_cdb16(u8 *cmd,
> {
> cdb_info->fua = GET_U8_FROM_CDB(cmd, IO_16_CDB_FUA_OFFSET) &
> IO_CDB_FUA_MASK;
> - cdb_info->prot_info = GET_U8_FROM_CDB(cmd, IO_16_CDB_WP_OFFSET) &
> - IO_CDB_WP_MASK >> IO_CDB_WP_SHIFT;
> + cdb_info->prot_info = (GET_U8_FROM_CDB(cmd, IO_16_CDB_WP_OFFSET) &
> + IO_CDB_WP_MASK) >> IO_CDB_WP_SHIFT;
> cdb_info->lba = GET_U64_FROM_CDB(cmd, IO_16_CDB_LBA_OFFSET);
> cdb_info->xfer_len = GET_U32_FROM_CDB(cmd, IO_16_CDB_TX_LEN_OFFSET);
> }