[PATCH 4.2.y-ckt 78/93] x86 EDAC, sb_edac.c: Repair damage introduced when "fixing" channel address

From: Kamal Mostafa
Date: Tue Apr 26 2016 - 14:19:51 EST


4.2.8-ckt9 -stable review patch. If anyone has any objections, please let me know.

---8<------------------------------------------------------------

From: Tony Luck <tony.luck@xxxxxxxxx>

commit ff15e95c82768d589957dbb17d7eb7dba7904659 upstream.

In commit:

eb1af3b71f9d ("Fix computation of channel address")

I switched the "sck_way" variable from holding the log2 value read
from the h/w to instead be the actual number. Unfortunately it
is needed in log2 form when used to shift the address.

Tested-by: Patrick Geary <patrickg@xxxxxxxxxxxxxx>
Signed-off-by: Tony Luck <tony.luck@xxxxxxxxx>
Acked-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxx>
Cc: Aristeu Rozanski <arozansk@xxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: linux-edac@xxxxxxxxxxxxxxx
Fixes: eb1af3b71f9d ("Fix computation of channel address")
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
Signed-off-by: Kamal Mostafa <kamal@xxxxxxxxxxxxx>
---
drivers/edac/sb_edac.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/edac/sb_edac.c b/drivers/edac/sb_edac.c
index 9c61607..fa3460b 100644
--- a/drivers/edac/sb_edac.c
+++ b/drivers/edac/sb_edac.c
@@ -1356,7 +1356,7 @@ static int get_memory_error_data(struct mem_ctl_info *mci,
}

ch_way = TAD_CH(reg) + 1;
- sck_way = 1 << TAD_SOCK(reg);
+ sck_way = TAD_SOCK(reg);

if (ch_way == 3)
idx = addr >> 6;
@@ -1395,7 +1395,7 @@ static int get_memory_error_data(struct mem_ctl_info *mci,
switch(ch_way) {
case 2:
case 4:
- sck_xch = 1 << sck_way * (ch_way >> 1);
+ sck_xch = (1 << sck_way) * (ch_way >> 1);
break;
default:
sprintf(msg, "Invalid mirror set. Can't decode addr");
@@ -1431,7 +1431,7 @@ static int get_memory_error_data(struct mem_ctl_info *mci,

ch_addr = addr - offset;
ch_addr >>= (6 + shiftup);
- ch_addr /= ch_way * sck_way;
+ ch_addr /= sck_xch;
ch_addr <<= (6 + shiftup);
ch_addr |= addr & ((1 << (6 + shiftup)) - 1);

--
2.7.4