Re: [Kernel 6.12.17] [PowerPC e5500] KVM HV compilation error

[Greg KH <gregkh@linuxfoundation.org>]

On Wed, Mar 05, 2025 at 03:14:13PM +0100, Christian Zigotzky wrote:
> Hi All,
> 
> The stable long-term kernel 6.12.17 cannot compile with KVM HV support for e5500 PowerPC machines anymore.
> 
> Bug report: https://github.com/chzigotzky/kernels/issues/6
> 
> Kernel config: https://github.com/chzigotzky/kernels/blob/6_12/configs/x5000_defconfig
> 
> Error messages:
> 
> arch/powerpc/kvm/e500_mmu_host.c: In function 'kvmppc_e500_shadow_map':
> arch/powerpc/kvm/e500_mmu_host.c:447:9: error: implicit declaration of function '__kvm_faultin_pfn' [-Werror=implicit-function-declaration]
>    pfn = __kvm_faultin_pfn(slot, gfn, FOLL_WRITE, NULL, &page);
>          ^~~~~~~~~~~~~~~~~
>   CC      kernel/notifier.o
> arch/powerpc/kvm/e500_mmu_host.c:500:2: error: implicit declaration of function 'kvm_release_faultin_page'; did you mean 'kvm_read_guest_page'? [-Werror=implicit-function-declaration]
>   kvm_release_faultin_page(kvm, page, !!ret, writable);
> 
> After that, I compiled it without KVM HV support.
> 
> Kernel config: https://github.com/chzigotzky/kernels/blob/6_12/configs/e5500_defconfig
> 
> Please check the error messages.

Odd, what commit caused this problem?  Any hint as to what commit is
missing to fix it?

thanks,

greg k-h