Re: [PATCH v3 3/5] arch: Register fchmodat4, usually as syscall 451

From: Arnd Bergmann
Date: Tue Jul 11 2023 - 07:32:15 EST


On Tue, Jul 11, 2023, at 13:25, Alexey Gladkov wrote:
> From: Palmer Dabbelt <palmer@xxxxxxxxxx>
>
> This registers the new fchmodat4 syscall in most places as nuber 451,
> with alpha being the exception where it's 561. I found all these sites
> by grepping for fspick, which I assume has found me everything.
>
> Signed-off-by: Palmer Dabbelt <palmer@xxxxxxxxxx>
> Signed-off-by: Alexey Gladkov <legion@xxxxxxxxxx>

In linux-6.5-rc1, number 451 is used for __NR_cachestat, the
next free one at the moment is 452.

> arch/arm/tools/syscall.tbl | 1 +
> arch/arm64/include/asm/unistd32.h | 2 ++

Unfortunately, you still also need to change __NR_compat_syscalls
in arch/arm64/include/asm/unistd.h. Aside from these two issues,
your patch is the correct way to hook up a new syscall.

Arnd