Commit-ID: 7fb0a5ee8889488f7568ffddffeb66ddeb50917e Gitweb: http://git.kernel.org/tip/7fb0a5ee8889488f7568ffddffeb66ddeb50917e Author: Nikunj A. Dadhania <nikunj@xxxxxxxxxxxxxxxxxx> AuthorDate: Mon, 9 Apr 2012 13:52:23 +0530 Committer: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> CommitDate: Wed, 11 Apr 2012 11:45:12 -0300 perf kvm: Finding struct machine fails for PERF_RECORD_MMAP Running 'perf kvm --host --guest --guestmount /tmp/guestmount record -a -g -- sleep 2' Was resulting in a segfault. For event type PERF_RECORD_MMAP, event->ip.pid is being used in perf_session__find_machine_for_cpumode, which is not correct. The event->ip.pid field happens to be 0 in this case and results in returning a NULL machine object. Finally, access to self->pid in machine__mmap_name, results in a segfault later. For PERF_RECORD_MMAP type, pass event->mmap.pid. Signed-off-by: Nikunj A. Dadhania <nikunj@xxxxxxxxxxxxxxxxxx> Reviewed-by: David Ahern <dsahern@xxxxxxxxx> Tested-by: David Ahern <dsahern@xxxxxxxxx> Cc: David Ahern <dsahern@xxxxxxxxx> Cc: Frederic Weisbecker <fweisbec@xxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Paul Mackerras <paulus@xxxxxxxxx> Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx> Cc: Stephane Eranian <eranian@xxxxxxxxxx> Cc: Nikunj A. Dadhania <nikunj@xxxxxxxxxxxxxxxxxx> Link: http://lkml.kernel.org/r/20120409081835.10576.22018.stgit@xxxxxxxxxxxxxxxxxxxx Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> --- tools/perf/util/session.c | 12 ++++++++++-- 1 files changed, 10 insertions(+), 2 deletions(-) diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c index 9412e3b..00923cd 100644 --- a/tools/perf/util/session.c +++ b/tools/perf/util/session.c @@ -826,8 +826,16 @@ static struct machine * { const u8 cpumode = event->header.misc & PERF_RECORD_MISC_CPUMODE_MASK; - if (cpumode == PERF_RECORD_MISC_GUEST_KERNEL && perf_guest) - return perf_session__find_machine(session, event->ip.pid); + if (cpumode == PERF_RECORD_MISC_GUEST_KERNEL && perf_guest) { + u32 pid; + + if (event->header.type == PERF_RECORD_MMAP) + pid = event->mmap.pid; + else + pid = event->ip.pid; + + return perf_session__find_machine(session, pid); + } return perf_session__find_host_machine(session); } -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html