[PATCH 4.4 028/163] x86 EDAC, sb_edac.c: Repair damage introduced when "fixing" channel address

[Greg Kroah-Hartman]

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

------------------

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: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/edac/sb_edac.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

--- a/drivers/edac/sb_edac.c
+++ b/drivers/edac/sb_edac.c
@@ -1396,7 +1396,7 @@ static int get_memory_error_data(struct
 	}
 
 	ch_way = TAD_CH(reg) + 1;
-	sck_way = 1 << TAD_SOCK(reg);
+	sck_way = TAD_SOCK(reg);
 
 	if (ch_way == 3)
 		idx = addr >> 6;
@@ -1435,7 +1435,7 @@ static int get_memory_error_data(struct
 		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");
@@ -1471,7 +1471,7 @@ static int get_memory_error_data(struct
 
 	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);