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| author | Xi Wang <xi.wang@gmail.com> | 2012-11-16 14:40:03 -0500 |
|---|---|---|
| committer | James Bottomley <JBottomley@Parallels.com> | 2012-11-30 09:20:17 +0000 |
| commit | beecadea1b8d67f591b13f7099559f32f3fd601d (patch) | |
| tree | e96c70ef947343902268e9d6d294333f275706aa | |
| parent | 072f19b4bea31cdd482d79f805413f2f9ac9e233 (diff) | |
| download | linux-3.10-beecadea1b8d67f591b13f7099559f32f3fd601d.tar.gz linux-3.10-beecadea1b8d67f591b13f7099559f32f3fd601d.tar.bz2 linux-3.10-beecadea1b8d67f591b13f7099559f32f3fd601d.zip | |
[SCSI] mvsas: fix undefined bit shift
The macro bit(n) is defined as ((u32)1 << n), and thus it doesn't work
with n >= 32, such as in mvs_94xx_assign_reg_set():
if (i >= 32) {
mvi->sata_reg_set |= bit(i);
...
}
The shift ((u32)1 << n) with n >= 32 also leads to undefined behavior.
The result varies depending on the architecture.
This patch changes bit(n) to do a 64-bit shift. It also simplifies
mv_ffc64() using __ffs64(), since invoking ffz() with ~0 is undefined.
Signed-off-by: Xi Wang <xi.wang@gmail.com>
Acked-by: Xiangliang Yu <yuxiangl@marvell.com>
Cc: stable@vger.kernel.org
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
| -rw-r--r-- | drivers/scsi/mvsas/mv_94xx.h | 14 | ||||
| -rw-r--r-- | drivers/scsi/mvsas/mv_sas.h | 2 |
2 files changed, 3 insertions, 13 deletions
diff --git a/drivers/scsi/mvsas/mv_94xx.h b/drivers/scsi/mvsas/mv_94xx.h index 8f7eb4f2114..487aa6f9741 100644 --- a/drivers/scsi/mvsas/mv_94xx.h +++ b/drivers/scsi/mvsas/mv_94xx.h @@ -258,21 +258,11 @@ enum sas_sata_phy_regs { #define SPI_ADDR_VLD_94XX (1U << 1) #define SPI_CTRL_SpiStart_94XX (1U << 0) -#define mv_ffc(x) ffz(x) - static inline int mv_ffc64(u64 v) { - int i; - i = mv_ffc((u32)v); - if (i >= 0) - return i; - i = mv_ffc((u32)(v>>32)); - - if (i != 0) - return 32 + i; - - return -1; + u64 x = ~v; + return x ? __ffs64(x) : -1; } #define r_reg_set_enable(i) \ diff --git a/drivers/scsi/mvsas/mv_sas.h b/drivers/scsi/mvsas/mv_sas.h index c04a4f5b597..da249553858 100644 --- a/drivers/scsi/mvsas/mv_sas.h +++ b/drivers/scsi/mvsas/mv_sas.h @@ -69,7 +69,7 @@ extern struct kmem_cache *mvs_task_list_cache; #define DEV_IS_EXPANDER(type) \ ((type == EDGE_DEV) || (type == FANOUT_DEV)) -#define bit(n) ((u32)1 << n) +#define bit(n) ((u64)1 << n) #define for_each_phy(__lseq_mask, __mc, __lseq) \ for ((__mc) = (__lseq_mask), (__lseq) = 0; \ |