On Tue, 2021-03-16 at 10:20 +0900, Hajime Tazaki wrote:

quoted

quoted

-	if (sigprocmask(SIG_UNBLOCK, &sig_mask, NULL) < 0)
-		panic("sigprocmask failed - errno = %d\n", errno);
+	if (pthread_sigmask(SIG_UNBLOCK, &sig_mask, NULL) < 0)
+		panic("pthread_sigmask failed - errno = %d\n", errno);

UML doesn't normally link with libpthread, and LKL doesn't actually
appear to require it either (since it has its lkl_thread and all), so
this seems wrong?

I think both UML/LKL link with libpthread.  See old
scripts/link-vmlinux.sh, or [01/20] patch.

-		${CC} ${CFLAGS_vmlinux}				\
-			${strip_debug}				\
-			-o ${output}				\
-			-Wl,-T,${lds}				\
-			${objects}				\
-			-lutil -lrt -lpthread
-		rm -f linux

Interesting. You're right, I really didn't expect that, nor did I ever
see that before.

How does this interact with all the clone() calls etc. that UML does?

johannes