On 2021/2/8 5:51, Arnd Bergmann wrote:

On Sun, Feb 7, 2021 at 9:18 AM Zhou Wang [off-list ref] wrote:

quoted

diff --git a/arch/arm64/include/asm/unistd32.h b/arch/arm64/include/asm/unistd32.h
index cccfbbe..3f49529 100644
--- a/arch/arm64/include/asm/unistd32.h
+++ b/arch/arm64/include/asm/unistd32.h

@@ -891,6 +891,8 @@ __SYSCALL(__NR_faccessat2, sys_faccessat2)
 __SYSCALL(__NR_process_madvise, sys_process_madvise)
 #define __NR_epoll_pwait2 441
 __SYSCALL(__NR_epoll_pwait2, compat_sys_epoll_pwait2)
+#define __NR_mempinfd 442
+__SYSCALL(__NR_mempinfd, sys_mempinfd)

This adds a compat syscall for 32-bit tasks running on arm64 without adding
the same for the native arch/arm syscall table. Those two need to always
stay synchronized. In fact, new system call should ideally get assigned
on all architectures at the same time, with the same number (or +110
on arch/alpha).

Thank for pointing out this. I use an ARM64 machine to test, so
currently only add it for ARM64 :)

Best,
Zhou

         Arnd

.