Re: [PATCH] s390: fix build error for sys_call_table_emu

Heiko Carstens
2020-06-18T11:28:02Z

On Thu, Jun 18, 2020 at 07:03:20PM +0800, Xiaoming Ni wrote:
> Build error on s390:
> arch/s390/kernel/entry.o: in function `sys_call_table_emu':
> >> (.rodata+0x1288): undefined reference to `__s390_'
>
> In commit ("All arch: remove system call sys_sysctl")
> 148 common fdatasync sys_fdatasync sys_fdatasync
> -149 common _sysctl sys_sysctl compat_sys_sysctl
> +149 common _sysctl sys_ni_syscall
> 150 common mlock sys_mlock sys_mlock
>
> After the patch is integrated, there is a format error in the generated
> arch/s390/include/generated/asm/syscall_table.h:
> SYSCALL(sys_fdatasync, sys_fdatasync)
> SYSCALL(sys_ni_syscall,) /* cause build error */
> SYSCALL(sys_mlock,sys_mlock)
>
> There are holes in the system call number in
> arch/s390/kernel/syscalls/syscall.tbl. When generating syscall_table.h,
> these hole numbers will be automatically filled with "NI_SYSCALL".
> Therefore, delete the number 149 to fix the current compilation failure.
> Similarly, modify tools/perf/arch/s390/entry/syscalls/syscall.tbl.
>
> Fixes: ("All arch: remove system call sys_sysctl")
> Fixes: https://lore.kernel.org/linuxppc-dev/20200616030734.87257-1-nixiaoming@huawei.com/
> Reported-by: kernel test robot <lkp@intel.com>
> Signed-off-by: Xiaoming Ni <nixiaoming@huawei.com>
> ---
> arch/s390/kernel/syscalls/syscall.tbl | 1 -
> tools/perf/arch/s390/entry/syscalls/syscall.tbl | 1 -
> 2 files changed, 2 deletions(-)
>
> diff --git a/arch/s390/kernel/syscalls/syscall.tbl b/arch/s390/kernel/syscalls/syscall.tbl
> index f17aaf6fe5de..bcaf93994e3c 100644
> --- a/arch/s390/kernel/syscalls/syscall.tbl
> +++ b/arch/s390/kernel/syscalls/syscall.tbl
> @@ -138,7 +138,6 @@
> 146 common writev sys_writev compat_sys_writev
> 147 common getsid sys_getsid sys_getsid
> 148 common fdatasync sys_fdatasync sys_fdatasync
> -149 common _sysctl sys_ni_syscall

This is not correct. It should be changed to:

149 common _sysctl - -

Otherwise the generated __NR__sysctl define will be lost from
unistd.h, which should not happen. Looking at the link above it
_looks_ like a similar mistake was done for arm64.

> diff --git a/tools/perf/arch/s390/entry/syscalls/syscall.tbl b/tools/perf/arch/s390/entry/syscalls/syscall.tbl
> index 0193f9b98753..eb77d0d01d8f 100644
> --- a/tools/perf/arch/s390/entry/syscalls/syscall.tbl
> +++ b/tools/perf/arch/s390/entry/syscalls/syscall.tbl
> @@ -138,7 +138,6 @@
> 146 common writev sys_writev compat_sys_writev
> 147 common getsid sys_getsid sys_getsid
> 148 common fdatasync sys_fdatasync sys_fdatasync
> -149 common _sysctl sys_ni_syscall

Same here.