Hi, James,
At least on MIPS (Loongson-3), we found that this patch is necessary.
Huacai
------------------ Original ------------------ From: "James Smart"james.smart@broadcom.com; Date: Mon, Mar 5, 2018 11:37 PM To: "陈华才"chenhc@lemote.com; "Dick Kennedy"dick.kennedy@broadcom.com; Cc: "James E . J . Bottomley"jejb@linux.vnet.ibm.com; "Martin K . Petersen"martin.petersen@oracle.com; "Fuxin Zhang"zhangfx@lemote.com; "linux-scsi"linux-scsi@vger.kernel.org; "stable"stable@vger.kernel.org; Subject: Re: [PATCH] scsi: lpfc: Switch memcpy_fromio() to __read32_copy()
On 3/4/2018 10:56 PM, 陈华才 wrote:
No one has the same problem? Or this patch need improve?
Huacai ------------------ Original ------------------ From: "陈华才"chenhc@lemote.com; Date: Thu, Mar 1, 2018 01:59 PM To: "James Smart"james.smart@broadcom.com; "Dick Kennedy"dick.kennedy@broadcom.com; Cc: "James E . J . Bottomley"jejb@linux.vnet.ibm.com; "Martin K . Petersen"martin.petersen@oracle.com; "Fuxin Zhang"zhangfx@lemote.com; "linux-scsi"linux-scsi@vger.kernel.org; "stable"stable@vger.kernel.org; Subject: Re:[PATCH] scsi: lpfc: Switch memcpy_fromio() to __read32_copy() Ping? ------------------ Original ------------------ From: "Huacai Chen"chenhc@lemote.com; Date: Fri, Jan 26, 2018 08:53 PM To: "James Smart"james.smart@broadcom.com; "Dick Kennedy"dick.kennedy@broadcom.com; Cc: "James E . J . Bottomley"jejb@linux.vnet.ibm.com; "Martin K . Petersen"martin.petersen@oracle.com; "Fuxin Zhang"zhangfx@lemote.com; "linux-scsi"linux-scsi@vger.kernel.org; "Huacai Chen"chenhc@lemote.com; "stable"stable@vger.kernel.org; Subject: [PATCH] scsi: lpfc: Switch memcpy_fromio() to __read32_copy() In commit bc73905abf770192 ("[SCSI] lpfc 8.3.16: SLI Additions, updates, and code cleanup"), lpfc_memcpy_to_slim() have switched memcpy_toio() to __write32_copy() in order to prevent unaligned 64 bit copy. Recently, we found that lpfc_memcpy_from_slim() have similar issues, so let it switch memcpy_fromio() to __read32_copy().
Cc: stable@vger.kernel.org Signed-off-by: Huacai Chen chenhc@lemote.com
drivers/scsi/lpfc/lpfc_compat.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/scsi/lpfc/lpfc_compat.h b/drivers/scsi/lpfc/lpfc_compat.h index 6b32b0a..47d4fad 100644 --- a/drivers/scsi/lpfc/lpfc_compat.h +++ b/drivers/scsi/lpfc/lpfc_compat.h @@ -91,8 +91,8 @@ lpfc_memcpy_to_slim( void __iomem *dest, void *src, unsigned int bytes) static inline void lpfc_memcpy_from_slim( void *dest, void __iomem *src, unsigned int bytes) {
- /* actually returns 1 byte past dest */
- memcpy_fromio( dest, src, bytes);
- /* convert bytes in argument list to word count for copy function */
- __ioread32_copy(dest, src, bytes / sizeof(uint32_t)); }
#endif /* __BIG_ENDIAN */
Huacai,
Note: the original change was 7 yrs ago and we've had no reports of issues. but....
This change didn't look necessary as the memcpy_XXXio() should allow byte alignments and byte-based lengths. Which means the original patch also wasn't necessary, which implies that the platform that had the issues has an api restriction not normally found on the other platforms.
I have no problem with the change though.
-- james
Signed-off-by: James Smart james.smart@broadcom.com