Re: [PATCH v2 04/27] locking/atomic: make atomic*_{cmp,}xchg optional

From: Linux regression tracking (Thorsten Leemhuis)
Date: Sat Jul 08 2023 - 09:07:58 EST


On 27.06.23 19:07, Guenter Roeck wrote:
> On Mon, Jun 05, 2023 at 08:01:01AM +0100, Mark Rutland wrote:
>> Most architectures define the atomic/atomic64 xchg and cmpxchg
>> operations in terms of arch_xchg and arch_cmpxchg respectfully.
>>
>> Add fallbacks for these cases and remove the trivial cases from arch
>> code. On some architectures the existing definitions are kept as these
>> are used to build other arch_atomic*() operations.
>>
>> Signed-off-by: Mark Rutland <mark.rutland@xxxxxxx>
> [...]
>
> This patch results in:
>
> ERROR: modpost: "__xchg_called_with_bad_pointer" [lib/atomic64_test.ko] undefined!
>
> when trying to build sparc64:allmodconfig.

Guenter, please correct me if I'm wrong:

This is fixed by Arnd's patch "sparc: mark __arch_xchg() as
__always_inline", but that afaics sadly hasn't even reached -next yet.
https://lore.kernel.org/all/20230628094938.2318171-1-arnd@xxxxxxxxxx/

Hence adding it to the tracking now that the end of the merge window is
near:

#regzbot ^introduced d12157efc8e083c7
#regzbot title locking/atomic: build error on sparc64:allmodconfig
#regzbot ignore-activity

Ciao, Thorsten (wearing his 'the Linux kernel's regression tracker' hat)
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