RE: Linux 6.1-rc3 build fail in include/linux/bpf.h

[David Laight <David.Laight@ACULAB.COM>]

From: David Laight
> Sent: 31 October 2022 11:15
> 
> The 6.1-rc3 sources fail to build because bpf.h unconditionally
> #define BPF_DISPATCHER_ATTRIBUTES __attribute__((patchable_function_entry(5)))
> for X86_64 builds.
> 
> I'm pretty sure that should depend on some other options
> since the compiler isn't required to support it.
> (The gcc 7.5.0 on my Ubunti 18.04 system certainly doesn't)
> 
> The only other reference to that attribute is in the definition
> of 'notrace' in compiler.h.

I think patchable_function_entry was added in gcc 8.
Documentation/process/changes.rst gives the minimal gcc version for
building the kernel as 5.1.

I doubt a increasing it to 8 is acceptable.

	David

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