Re: [PATCH 2/3] x86/cpuid: fix unbootable VMs by really inlining memcmp() in hypervisor_cpuid_base()

[Jürgen Groß]

On 22.04.26 22:07, Mauricio Faria de Oliveira wrote:
> Even with __builtin the compiler may decide to use the out of line function
> instead of the inline implementation.
>
> The existing code is broken with gcc-14/15 but not gcc-12/13 (Ubuntu 25.10)
> and vmlinux no longer boots with CONFIG_PVH if CONFIG_KASAN_GENERIC is set.
>
> For testing purposes, if the size argument is reduced from 12 to 8 then the
> compiler decides to use the inline implementation; that shows results vary.
>
> Switch the builtin to the inline implementation to address it.
>
> Fixes: 416a33c9afce ("x86/cpu: fix unbootable VMs by inlining memcmp() in hypervisor_cpuid_base()")
> Signed-off-by: Mauricio Faria de Oliveira <mfo@xxxxxxxxxx>

Reviewed-by: Juergen Gross <jgross@xxxxxxxx>


Juergen

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