From: Igor Kovalenko <igor.v.kovalenko@xxxxxxxxx> Date: Sun, 6 Dec 2009 01:27:08 +0300 > I wonder if mcount ever works on sparc64, if it does work indeed I'd > like to know what I'm missing there. Yep, two distinct bugs there. Please try this patch, thanks for the report. sparc64: Fix stack debugging IRQ stack regression. Commit 4f70f7a91bffdcc39f088748dc678953eb9a3fbd (sparc64: Implement IRQ stacks.) has two bugs. First, the softirq range check forgets to subtract STACK_BIAS before comparing with %sp. Next, on failure the wrong label is jumped to, resulting in a bogus stack being loaded. Reported-by: Igor Kovalenko <igor.v.kovalenko@xxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> diff --git a/arch/sparc/lib/mcount.S b/arch/sparc/lib/mcount.S index 7ce9c65..24b8b12 100644 --- a/arch/sparc/lib/mcount.S +++ b/arch/sparc/lib/mcount.S @@ -64,8 +64,9 @@ mcount: 2: sethi %hi(softirq_stack), %g3 or %g3, %lo(softirq_stack), %g3 ldx [%g3 + %g1], %g7 + sub %g7, STACK_BIAS, %g7 cmp %sp, %g7 - bleu,pt %xcc, 2f + bleu,pt %xcc, 3f sethi %hi(THREAD_SIZE), %g3 add %g7, %g3, %g7 cmp %sp, %g7 @@ -75,7 +76,7 @@ mcount: * again, we are already trying to output the stack overflow * message. */ - sethi %hi(ovstack), %g7 ! cant move to panic stack fast enough +3: sethi %hi(ovstack), %g7 ! cant move to panic stack fast enough or %g7, %lo(ovstack), %g7 add %g7, OVSTACKSIZE, %g3 sub %g3, STACK_BIAS + 192, %g3 -- To unsubscribe from this list: send the line "unsubscribe sparclinux" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html