On 201014 1009, Darren Kenny wrote: > On Tuesday, 2020-10-13 at 17:52:46 +01, Daniel P. Berrangé wrote: > > On Tue, Oct 13, 2020 at 05:50:37PM +0100, Darren Kenny wrote: > >> Hi Alex, > >> > >> This mentions the use of atexit() to perform some cleanup, but I'm not > >> seeing that being added here, should it be? > > > > The reference to atexit is strange, because it says the only way to > > kill the fuzzer is SIGKILL, and that won't let atexit handlers run > > anyway. > > > > OK, I understand the context now, it is in reference to Dima's patchset: > > - > https://lore.kernel.org/qemu-devel/cover.1602078083.git.dimas...@yandex-team.ru/ > > Where Alex suggested using atexit() to clean up the left over files from > the test. > > And with regard to SIGKILL, I believe it is that today, before Alex's > patch that is the only way to stop the fuzzer running - which I can > attest to since I've found it hard to stop in the past :) > > Resetting these signal handlers to the default behaviour would allow the > process to be terminated and an atexit() used, as Alex mentioned. > > Alex, if you could clarify the commit message, then I feel this does > make sent to change in the fuzz testing code, so: >
Yes - sorry about the confusion. -Alex > Reviewed-by: Darren Kenny <darren.ke...@oracle.com> > > Thanks, > > Darren. > > >> > >> Thanks, > >> > >> Darren. > >> > >> On Tuesday, 2020-10-13 at 11:29:20 -04, Alexander Bulekov wrote: > >> > With the fuzzer, we never call main_loop_should_exit, since we manually > >> > call main_loop_wait. This means that the only way to terminate the > >> > fuzzer is with SIGKILL. Disable the signal handlers, so there are > >> > reasonable ways to terminate the fuzzer and use atexit() to clean-up > >> > after the fuzzer. > >> > > >> > Signed-off-by: Alexander Bulekov <alx...@bu.edu> > >> > --- > >> > tests/qtest/fuzz/fuzz.c | 8 ++++++++ > >> > 1 file changed, 8 insertions(+) > >> > > >> > diff --git a/tests/qtest/fuzz/fuzz.c b/tests/qtest/fuzz/fuzz.c > >> > index d926c490c5..eb0070437f 100644 > >> > --- a/tests/qtest/fuzz/fuzz.c > >> > +++ b/tests/qtest/fuzz/fuzz.c > >> > @@ -217,5 +217,13 @@ int LLVMFuzzerInitialize(int *argc, char ***argv, > >> > char ***envp) > >> > /* re-enable the rcu atfork, which was previously disabled in > >> > qemu_init */ > >> > rcu_enable_atfork(); > >> > > >> > + /* > >> > + * Disable QEMU's signal handlers, since we manually control the > >> > main_loop, > >> > + * and don't check for main_loop_should_exit > >> > + */ > >> > + signal(SIGINT, SIG_DFL); > >> > + signal(SIGHUP, SIG_DFL); > >> > + signal(SIGTERM, SIG_DFL); > >> > + > >> > return 0; > >> > } > >> > -- > >> > 2.28.0 > >> > > > > Regards, > > Daniel > > -- > > |: https://berrange.com -o- https://www.flickr.com/photos/dberrange > > :| > > |: https://libvirt.org -o- https://fstop138.berrange.com > > :| > > |: https://entangle-photo.org -o- https://www.instagram.com/dberrange > > :|
