| Message ID | 20230213125238.331881-5-iii@linux.ibm.com |
|---|---|
| State | New |
| Headers | show |
| Series | Fix deadlock when dying because of a signal | expand |
Ilya Leoshkevich <iii@linux.ibm.com> writes: > Check that dying due to a signal does not deadlock. > > Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> > Reviewed-by: Richard Henderson <richard.henderson@linaro.org> > --- > tests/tcg/multiarch/linux/linux-fork-trap.c | 48 +++++++++++++++++++++ > 1 file changed, 48 insertions(+) > create mode 100644 tests/tcg/multiarch/linux/linux-fork-trap.c > > diff --git a/tests/tcg/multiarch/linux/linux-fork-trap.c b/tests/tcg/multiarch/linux/linux-fork-trap.c > new file mode 100644 > index 00000000000..a921f875380 > --- /dev/null > +++ b/tests/tcg/multiarch/linux/linux-fork-trap.c > @@ -0,0 +1,48 @@ > +/* > + * Test that a fork()ed process terminates after __builtin_trap(). > + * > + * SPDX-License-Identifier: GPL-2.0-or-later > + */ > +#include <assert.h> > +#include <stdlib.h> > +#include <sys/resource.h> > +#include <sys/wait.h> > +#include <unistd.h> > + > +int main(void) > +{ > + struct rlimit nodump; > + pid_t err, pid; > + int wstatus; > + > + pid = fork(); > + assert(pid != -1); > + if (pid == 0) { > + /* We are about to crash on purpose; disable core dumps. */ I think we could benefit from two printfs in the test so the following: ➜ ./qemu-aarch64 ./tests/tcg/aarch64-linux-user/linux-fork-trap qemu: uncaught target signal 5 (Trace/breakpoint trap) - core dumped 🕙09:50:14 alex@zen:qemu.git/builds/arm.all on testing/next [$!?] ➜ echo $status 0 is a little less confusing. > + if (getrlimit(RLIMIT_CORE, &nodump)) { > + return EXIT_FAILURE; > + } > + nodump.rlim_cur = 0; > + if (setrlimit(RLIMIT_CORE, &nodump)) { > + return EXIT_FAILURE; > + } > + /* > + * An alternative would be to dereference a NULL pointer, but that > + * would be an UB in C. > + */ printf("about to trigger fault...\n"); > +#if defined(__MICROBLAZE__) > + /* > + * gcc emits "bri 0", which is an endless loop. > + * Take glibc's ABORT_INSTRUCTION. > + */ > + asm volatile("brki r0,-1"); > +#else > + __builtin_trap(); > +#endif > + } > + err = waitpid(pid, &wstatus, 0); > + assert(err == pid); > + assert(WIFSIGNALED(wstatus)); > + printf("faulting thread exited cleanly\n"); Othwerwise: Reviewed-by: Alex Bennée <alex.bennee@linaro.org> > + return EXIT_SUCCESS; > +}
diff --git a/tests/tcg/multiarch/linux/linux-fork-trap.c b/tests/tcg/multiarch/linux/linux-fork-trap.c new file mode 100644 index 00000000000..a921f875380 --- /dev/null +++ b/tests/tcg/multiarch/linux/linux-fork-trap.c @@ -0,0 +1,48 @@ +/* + * Test that a fork()ed process terminates after __builtin_trap(). + * + * SPDX-License-Identifier: GPL-2.0-or-later + */ +#include <assert.h> +#include <stdlib.h> +#include <sys/resource.h> +#include <sys/wait.h> +#include <unistd.h> + +int main(void) +{ + struct rlimit nodump; + pid_t err, pid; + int wstatus; + + pid = fork(); + assert(pid != -1); + if (pid == 0) { + /* We are about to crash on purpose; disable core dumps. */ + if (getrlimit(RLIMIT_CORE, &nodump)) { + return EXIT_FAILURE; + } + nodump.rlim_cur = 0; + if (setrlimit(RLIMIT_CORE, &nodump)) { + return EXIT_FAILURE; + } + /* + * An alternative would be to dereference a NULL pointer, but that + * would be an UB in C. + */ +#if defined(__MICROBLAZE__) + /* + * gcc emits "bri 0", which is an endless loop. + * Take glibc's ABORT_INSTRUCTION. + */ + asm volatile("brki r0,-1"); +#else + __builtin_trap(); +#endif + } + err = waitpid(pid, &wstatus, 0); + assert(err == pid); + assert(WIFSIGNALED(wstatus)); + + return EXIT_SUCCESS; +}