Re: [git pull] OProfile fixes for v2.6.28

[Eric Dumazet]

Robert Richter a écrit :
> Hi Ingo,
>
> please pull oprofile fixes for 2.6.28 for tip regression:
>
> git://git.kernel.org/pub/scm/linux/kernel/git/rric/oprofile.git oprofile-for-tip
>
> Thanks,
>
> -Robert
>
> Andi Kleen (1):
>       oprofile: Fix p6 counter overflow check
>
> Carl Love (2):
>       Cell OProfile: Incorrect local array size in activate spu profiling function
>       Cell OProfile: Incorrect local array size in activate spu profiling function
>
> Jesper Dangaard Brouer (1):
>       Change UTF8 chars in Kconfig help text about Oprofile AMD barcelona
>
> Nick Piggin (1):
>       oprofile: fix memory ordering
>
> Robert Richter (1):
>       Revert "Cell OProfile: Incorrect local array size in activate spu profiling function"

Hi Robert

I am still trying to find why oprofile stops after some millions of samples on my machine.

(All versions of linux supporting oprofile/NMI on this machine have this problem)
Note : I am using a 32bit kernel.

While doing code review I found this bug.

Impact: 32bit kernels, memory corruption

[PATCH] oprofile: fix an overflow in ppro code

reset_value was changed from long to u64 in commit b99170288421c79f0c2efa8b33e26e65f4bb7fb8
(oprofile: Implement Intel architectural perfmon support)

But dynamic allocation of this array use a wrong type (long instead of u64)

Signed-off-by: Eric Dumazet <dada1@xxxxxxxxxxxxx>
---
arch/x86/oprofile/op_model_ppro.c |    2 +-
1 files changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/oprofile/op_model_ppro.c b/arch/x86/oprofile/op_model_ppro.c
index 3f1b81a..716d26f 100644
--- a/arch/x86/oprofile/op_model_ppro.c
+++ b/arch/x86/oprofile/op_model_ppro.c
@@ -69,7 +69,7 @@ static void ppro_setup_ctrs(struct op_msrs const * const msrs)
 	int i;
 
 	if (!reset_value) {
-		reset_value = kmalloc(sizeof(unsigned) * num_counters,
+		reset_value = kmalloc(sizeof(reset_value[0]) * num_counters,
 					GFP_ATOMIC);
 		if (!reset_value)
 			return;