2009-03-06 09:35:58

by Paul Mackerras

Subject: [PATCH 1/3] perfcounters/powerpc: fix oops with multiple counters in a group

Impact: fix oops-causing bug

This fixes a bug in the powerpc hw_perf_counter_init where the code
didn't initialize ctrs[n] before passing the ctrs array to check_excludes,
leading to possible oopses and other incorrect behaviour. This fixes it
by initializing ctrs[n] correctly.

Signed-off-by: Paul Mackerras <[email protected]>
---
Ingo, please pull this series of 3 patches from my perfcounters.git
master branch at:

git://git.kernel.org/pub/scm/linux/kernel/git/paulus/perfcounters.git master

arch/powerpc/kernel/perf_counter.c | 1 +
1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/arch/powerpc/kernel/perf_counter.c b/arch/powerpc/kernel/perf_counter.c
index 112332d..4fec112 100644
--- a/arch/powerpc/kernel/perf_counter.c
+++ b/arch/powerpc/kernel/perf_counter.c
@@ -633,6 +633,7 @@ hw_perf_counter_init(struct perf_counter *counter)
return NULL;
}
events[n] = ev;
+ ctrs[n] = counter;
if (check_excludes(ctrs, n, 1))
return NULL;
if (power_check_constraints(events, n + 1))
--
1.5.6.3

2009-03-06 09:41:46

by Ingo Molnar

Subject: Re: [PATCH 1/3] perfcounters/powerpc: fix oops with multiple counters in a group

* Paul Mackerras <[email protected]> wrote:

> Ingo, please pull this series of 3 patches from my perfcounters.git
> master branch at:
>
> git://git.kernel.org/pub/scm/linux/kernel/git/paulus/perfcounters.git master

Pulled into tip:perfcounters/core, thanks Paul!

Note, Mike Galbraith updated both perfstat.c and kerneltop.c to
the new ABI, they can be picked up from:

http://redhat.com/~mingo/perfcounters/perfstat.c
http://redhat.com/~mingo/perfcounters/kerneltop.c

(I also extended kerneltop.c with the -r0x000 type of event IDs
to pass in raw event IDs.)

Ingo