Commit 82d86de25b9c99db546e17c6f7ebf9a691da557e "TLB lock recursive"
introduced a bug whereby cpu 0 uses the same value for "lock held" as
is used to indicate that the lock is free. This means that cpu 1 can
acquire the lock whenever it wants, regardless of whether cpu 0 has it
locked, which in turn means we can get duplicate TLB entries.
Add one to the CPU value to ensure we do not use zero as a "lock held"
value.
Signed-off-by: Scott Wood <scottw...@freescale.com>
---
arch/powerpc/mm/tlb_low_64e.S | 1 +
1 file changed, 1 insertion(+)
diff --git a/arch/powerpc/mm/tlb_low_64e.S b/arch/powerpc/mm/tlb_low_64e.S
index 3298d10..ba3ba3c 100644
--- a/arch/powerpc/mm/tlb_low_64e.S
+++ b/arch/powerpc/mm/tlb_low_64e.S
@@ -309,6 +309,7 @@ tlb_miss_common_e6500:
lhz r10,PACAPACAINDEX(r13)
cmpdi r15,0
cmpdi cr1,r15,1 /* set cr1.eq = 0 for non-recursive */
+ addi r10,r10,1
bne 2f
stbcx. r10,0,r11
bne 1b
--
1.9.1
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