Re: kern/54009: "l->l_pcu_cpu[id] == NULL" panic on aarch64

[Ryo Shimizu <ryo%nerv.org@localhost>]

I guess the cause is the lack of memory barrier.
Will the following patches fix it?


cvs -q diff -aup .
Index: subr_ipi.c
===================================================================
RCS file: /src/cvs/cvsroot-netbsd/src/sys/kern/subr_ipi.c,v
retrieving revision 1.4
diff -a -u -p -r1.4 subr_ipi.c
--- subr_ipi.c	6 Apr 2019 02:59:05 -0000	1.4
+++ subr_ipi.c	25 Aug 2019 19:23:47 -0000
@@ -331,6 +331,9 @@ ipi_msg_cpu_handler(void *arg __unused)
 		msg->func(msg->arg);
 
 		/* Ack the request. */
+#ifndef __HAVE_ATOMIC_AS_MEMBAR
+		membar_producer();
+#endif
 		atomic_dec_uint(&msg->_pending);
 	}
 }

-- 
ryo shimizu