Re: [PATCH 2.6.24-rc1] sata_promise: fix endianess bug in ASIC PRD bug workaround

2007-11-03 Thread Jeff Garzik

Mikael Pettersson wrote:

The original workaround for the Promise ASIC PRD bug
contained an endianess bug which I failed to detect:
the adjustment of the last PRD entry's length field
applied host arithmetic to little-endian data, which
is incorrect on big-endian machines.

We have the length available in host-endian format, so
do the adjustment on host-endian data and then convert
and store it in the PRD entry's little-endian data field.

Thanks to an anonymous reviewer for detecting this bug.

Signed-off-by: Mikael Pettersson <[EMAIL PROTECTED]>
---
Jeff: please include this fix in any backport(s) of the
ASIC PRD bug workaround.

 drivers/ata/sata_promise.c |2 +-
 1 files changed, 1 insertion(+), 1 deletion(-)

diff -rupN linux-2.6.24-rc1/drivers/ata/sata_promise.c 
linux-2.6.24-rc1.sata_promise-endianess-fix/drivers/ata/sata_promise.c
--- linux-2.6.24-rc1/drivers/ata/sata_promise.c 2007-10-31 11:47:13.0 
+0100
+++ linux-2.6.24-rc1.sata_promise-endianess-fix/drivers/ata/sata_promise.c  
2007-10-31 11:47:25.0 +0100
@@ -585,7 +585,7 @@ static void pdc_fill_sg(struct ata_queue
VPRINTK("Splitting last PRD.\n");
 
 			addr = le32_to_cpu(ap->prd[idx - 1].addr);

-   ap->prd[idx - 1].flags_len -= 
cpu_to_le32(SG_COUNT_ASIC_BUG);
+   ap->prd[idx - 1].flags_len = cpu_to_le32(len - 
SG_COUNT_ASIC_BUG);
VPRINTK("PRD[%u] = (0x%X, 0x%X)\n", idx - 1, addr, 
SG_COUNT_ASIC_BUG);
 
 			addr = addr + len - SG_COUNT_ASIC_BUG;

-


applied


-
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[PATCH 2.6.24-rc1] sata_promise: fix endianess bug in ASIC PRD bug workaround

2007-10-31 Thread Mikael Pettersson
The original workaround for the Promise ASIC PRD bug
contained an endianess bug which I failed to detect:
the adjustment of the last PRD entry's length field
applied host arithmetic to little-endian data, which
is incorrect on big-endian machines.

We have the length available in host-endian format, so
do the adjustment on host-endian data and then convert
and store it in the PRD entry's little-endian data field.

Thanks to an anonymous reviewer for detecting this bug.

Signed-off-by: Mikael Pettersson <[EMAIL PROTECTED]>
---
Jeff: please include this fix in any backport(s) of the
ASIC PRD bug workaround.

 drivers/ata/sata_promise.c |2 +-
 1 files changed, 1 insertion(+), 1 deletion(-)

diff -rupN linux-2.6.24-rc1/drivers/ata/sata_promise.c 
linux-2.6.24-rc1.sata_promise-endianess-fix/drivers/ata/sata_promise.c
--- linux-2.6.24-rc1/drivers/ata/sata_promise.c 2007-10-31 11:47:13.0 
+0100
+++ linux-2.6.24-rc1.sata_promise-endianess-fix/drivers/ata/sata_promise.c  
2007-10-31 11:47:25.0 +0100
@@ -585,7 +585,7 @@ static void pdc_fill_sg(struct ata_queue
VPRINTK("Splitting last PRD.\n");
 
addr = le32_to_cpu(ap->prd[idx - 1].addr);
-   ap->prd[idx - 1].flags_len -= 
cpu_to_le32(SG_COUNT_ASIC_BUG);
+   ap->prd[idx - 1].flags_len = cpu_to_le32(len - 
SG_COUNT_ASIC_BUG);
VPRINTK("PRD[%u] = (0x%X, 0x%X)\n", idx - 1, addr, 
SG_COUNT_ASIC_BUG);
 
addr = addr + len - SG_COUNT_ASIC_BUG;
-
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