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author | Scott Wood <scottwood@freescale.com> | 2014-05-22 21:10:35 (GMT) |
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committer | Scott Wood <scottwood@freescale.com> | 2014-06-20 23:48:30 (GMT) |
commit | 1cb4ed92f6a5a8961b122d11e651870ba741245b (patch) | |
tree | fef4fb40f49ff85d449410711a6c434a3d35b236 /arch/powerpc/mm/tlb_low_64e.S | |
parent | bbd08c72c6b3344a230e15264d6cd444ed76b958 (diff) | |
download | linux-1cb4ed92f6a5a8961b122d11e651870ba741245b.tar.xz |
powerpc/e6500: hw tablewalk: fix recursive tlb lock on cpu 0
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 <scottwood@freescale.com>
Reported-by: Ed Swarthout <ed.swarthout@freescale.com>
Diffstat (limited to 'arch/powerpc/mm/tlb_low_64e.S')
-rw-r--r-- | arch/powerpc/mm/tlb_low_64e.S | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/arch/powerpc/mm/tlb_low_64e.S b/arch/powerpc/mm/tlb_low_64e.S index 3298d10..131f1f4 100644 --- a/arch/powerpc/mm/tlb_low_64e.S +++ b/arch/powerpc/mm/tlb_low_64e.S @@ -296,7 +296,7 @@ itlb_miss_fault_bolted: * r14 = page table base * r13 = PACA * r11 = tlb_per_core ptr - * r10 = cpu number + * r10 = crap (free to use) */ tlb_miss_common_e6500: /* @@ -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 |