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 <paulus@samba.org>

diff --git a/arch/powerpc/kernel/perf_counter.c b/arch/powerpc/kernel/perf_counter.c
index 112332d07fc26499aab535c559d9ec0cf4079583..4fec112386fce8aea04c4c1d92768d007411d36b 100644 (file)
--- 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))