Re: [PATCH v9 14/15] arm: Reorganize syscall table and separated the ABIs

["Arnd Bergmann" <arnd@arndb.de>]

On Thu, Nov 5, 2026, at 21:05, André Almeida wrote:
> arm has three ABIs: EABI, OABI and OABI with compat (OABIC). Those ABIs
> shares almost every syscall, but have a few exceptions: some syscalls only
> have an entry point for OABI/C (e.g. sys_alarm), and some syscalls have a
> special entry point for OABIC (e.g. sys_oabi_pwrite64).
>
> Currently, the syscall table uses the compat column to specify when such
> OABI syscall needs an OABIC entry point. However, this makes tricky to move
> arm to use the common syscall table: arm doesn't use the compat entry
> points for time64 (e.g. compat_sys_pselect6_time64) and rely on the normal
> entry point (e.g. sys_pselect6). Given that the build system will generate
> the same __SYSCALL_WITH_COMPAT() macro for the whole table, this would
> create inconsistency where some syscalls would point to the wrong entry.
>
> To avoid this problem and prepare the architecture to move to the common
> table, separate explicitly the ABIs in the local syscall table and drop all
> entries for the compat column. Make sure that __SYSCALL_WITH_COMPAT()
> always points to the native option.
>
> Signed-off-by: André Almeida <andrealmeid@igalia.com>
> ---
> This patch was tested comparing the results of `$ strings
> arch/arm/kernel/entry-common.o` before and after this patch.

Aside from the two mistakes that sashiko found, thsi looks fine.

Two related points though:

 - hopefully we can expedite dropping OABI support now, as there was
   a report today about how it has been broken for the past 5 years.

 - on top of this patch, it should be much easier to merge this file
   with the arm64 version of the arm eabi table. On the other hand,
   that can probably wait until OABI is actually gone.

      Arnd