[PATCH] x32: Switch back to assembly syscall wrapper for prctl

[H.J. Lu]

On Thu, Dec 4, 2025 at 10:06 PM Adhemerval Zanella Netto
<adhemerval.zanella@linaro.org> wrote:
>
> The x32 and or1k (which also uses similar implementation) does seems broken
> without checking the 'option' argument to see which arg we can va_arg.
>
> The problem is adding this logic on libc will add some forward-compatibility
> that we try to avoid (newer kernel prctl additions might now work correctly).
>
> I am not sure why we haven't switch x32 back to the assembly wrappers
> with 6a04404521ac4119ae36827eeb288ea84eee7cf6 fix (BZ#29770).  H.J, can
> use remove the x32 C version (and also or1k as well)?

Since the variadic prctl function takes at most 5 integer arguments which
are passed in the same integer registers on x32 as the function with 5
integer arguments, we can safely use assembly syscall wrapper for prctl
for x32.

Tested on x32.  I leave or1k alone since I don't know if it is safe to
do the same.

-- 
H.J.
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