diff options
| author | Alexander Bulekov <alxndr@bu.edu> | 2020-02-19 23:11:10 -0500 |
|---|---|---|
| committer | Stefan Hajnoczi <stefanha@redhat.com> | 2020-02-22 08:26:48 +0000 |
| commit | d6919e4cb65230b0c8081eb072893d4e8a191a59 (patch) | |
| tree | 103b32504913231f87035418dc7cab7558794c8d | |
| parent | a028edeaa6f1c154f06e16440e46b0f876a64077 (diff) | |
main: keep rcu_atfork callback enabled for qtest
The qtest-based fuzzer makes use of forking to reset-state between
tests. Keep the callback enabled, so the call_rcu thread gets created
within the child process.
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20200220041118.23264-15-alxndr@bu.edu
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
| -rw-r--r-- | softmmu/vl.c | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/softmmu/vl.c b/softmmu/vl.c index 080d3b5106..92c7b3a6e9 100644 --- a/softmmu/vl.c +++ b/softmmu/vl.c @@ -3782,7 +3782,17 @@ void qemu_init(int argc, char **argv, char **envp) set_memory_options(&ram_slots, &maxram_size, machine_class); os_daemonize(); - rcu_disable_atfork(); + + /* + * If QTest is enabled, keep the rcu_atfork enabled, since system processes + * may be forked testing purposes (e.g. fork-server based fuzzing) The fork + * should happen before a signle cpu instruction is executed, to prevent + * deadlocks. See commit 73c6e40, rcu: "completely disable pthread_atfork + * callbacks as soon as possible" + */ + if (!qtest_enabled()) { + rcu_disable_atfork(); + } if (pid_file && !qemu_write_pidfile(pid_file, &err)) { error_reportf_err(err, "cannot create PID file: "); |