Re: [patch 00/18] entry: Consolidate and rework syscall entry handling

Magnus!

On Sun, Jul 19 2026 at 13:25, Magnus Lindholm wrote:
> One Alpha-specific wrinkle I hit while rebasing the GENERIC_ENTRY patch is
> that Alpha cannot unconditionally pre-seed the normal -ENOSYS return state
> before calling into the generic entry code: syscall_set_return_value() also
> updates r19/a3, which is still syscall argument 4 on the normal entry path.
> Doing that too early broke early userspace mmap() during boot.

Similar to what Peter and me suggested in the related discussion
vs. s390 which has a similar issue, you can just have a dedicated
syscall_return member in your pt_regs struct, which is preset to -ENOSYS
and operate on that. You have an unused padding entry there which means
it won't even change the size.

> Are you planning to send a v2 with the seccomp recheck fix and any other
> review fixups folded in? Is the intention to route this upstream
> during the next merge window?

You were on CC for the V2, no?

The whole pile including Jinjie's seccomp bypass fix is in

    git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git core/entry

and is targeted for the 7.3 merge window.

If you want to base your stuff on that for 7.3, I can add a tag which
makes it immutable so it can be pulled into the alpha tree.

Thanks,

        tglx