[tip:perf/core] perf kvm: Handle realloc failures

tip-bot for David Ahern
2013-05-31T11:50:40Z

Commit-ID: 6ca5f3081f903e2b25e58a061ddad486f846561e
Gitweb: http://git.kernel.org/tip/6ca5f3081f903e2b25e58a061ddad486f846561e
Author: David Ahern <dsahern@gmail.com>
AuthorDate: Sat, 25 May 2013 18:24:46 -0600
Committer: Arnaldo Carvalho de Melo <acme@redhat.com>
CommitDate: Tue, 28 May 2013 16:24:04 +0300

perf kvm: Handle realloc failures

Save previous pointer and free on failure.

Signed-off-by: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Runzhen Wang <runzhen@linux.vnet.ibm.com>
Cc: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1369527896-3650-7-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/perf/builtin-kvm.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/tools/perf/builtin-kvm.c b/tools/perf/builtin-kvm.c
index 533501e..24b78ae 100644
--- a/tools/perf/builtin-kvm.c
+++ b/tools/perf/builtin-kvm.c
@@ -328,6 +328,7 @@ static int kvm_events_hash_fn(u64 key)
static bool kvm_event_expand(struct kvm_event *event, int vcpu_id)
{
int old_max_vcpu = event->max_vcpu;
+ void *prev;

if (vcpu_id < event->max_vcpu)
return true;
@@ -335,9 +336,11 @@ static bool kvm_event_expand(struct kvm_event *event, int vcpu_id)
while (event->max_vcpu <= vcpu_id)
event->max_vcpu += DEFAULT_VCPU_NUM;

+ prev = event->vcpu;
event->vcpu = realloc(event->vcpu,
event->max_vcpu * sizeof(*event->vcpu));
if (!event->vcpu) {
+ free(prev);
pr_err("Not enough memory\n");
return false;
}