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 <6f3b246e-7417-4455-abe4-ca3b42fdda4c@linux-m68k.org>
Date: Tue, 20 Feb 2024 16:09:55 +0100
From: "Arnd Bergmann" <arnd@arndb.de>
To: "Greg Ungerer" <gerg@linux-m68k.org>, "Thomas Huth" <thuth@redhat.com>,
 linux-m68k@lists.linux-m68k.org, "Geert Uytterhoeven" <geert@linux-m68k.org>
Cc: linux-kernel@vger.kernel.org, "Oleg Nesterov" <oleg@redhat.com>
Subject: Re: [PATCH v2] m68k: Avoid CONFIG_COLDFIRE switch in uapi header
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On Tue, Feb 20, 2024, at 15:13, Greg Ungerer wrote:
> On 20/2/24 02:01, Thomas Huth wrote:
>> We should not use any CONFIG switches in uapi headers since these
>> only work during kernel compilation; they are not defined for
>> userspace. Fix it by moving the struct pt_regs to the kernel-internal
>> header instead - struct pt_regs does not seem to be required for
>> the userspace headers on m68k at all.
>> 
>> Suggested-by: Greg Ungerer <gerg@linux-m68k.org>
>> Signed-off-by: Thomas Huth <thuth@redhat.com>
>> ---
>>   v2: Move the struct instead of changing the #ifdef
>> 
>>   See previous discussion here:
>>   https://lore.kernel.org/lkml/6e3f2a2e-2430-4b4f-9ead-d9a4d5e42713@linux-m68k.org/
>
> I am fine with this. FWIW the following architectures do
> not define pt_regs in their uapi/ptrace.h header either:
> arc, arm64, loongarch, nios2, openrisc, riscv, s390, xtensa
> Though quite a few of them have a user_pt_regs instead.
>
> So for me:
>
> Acked-by: Greg Ungerer <gerg@linux-m68k.org>
>
> Geert, Arnd, do you have any thoughts on this?

It clearly doesn't change the ABI, so that part is fine.

If asm/ptrace.h is included by some userspace tool to
get the definition, it might cause a compile-time error
that needs a trivial source change.

This could be needed for ptrace (gdb, strace) or signal
handling and setjmp (libc), though it's more likely that these
already have their own copies.

     Arnd