Subject: Re: linux-next: build failure after merge of the kvm-arm tree

From: Paolo Bonzini <[email-masked]>
Date: Thu, 22 Feb 2024 14:11:54 +0100

On 2/22/24 12:40, Stephen Rothwell wrote:
>> This fails because https://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git/commit/?id=fdd867fe9b32
>> added new fields to that register (ID_AA64DFR1_EL1)
>>
>> and commit b80b701d5a6 ("KVM: arm64: Snapshot all non-zero RES0/RES1 sysreg fields for later checking")
>> took a snapshot of the fields, so the RES0 (reserved 0) bits don't match anymore.
>>
>> Not sure how to resolve it in the git branches though.
> 
> Thanks.  I will apply this patch to the merge of the kvm-arm tree from
> tomorrow (and at the end of today's tree).

Marc, Iliver, can you get a topic branch from Catalin and friends for 
this sysreg patch, and apply the fixup directly to the kvm-arm branch in 
the merge commit?

Not _necessary_, as I can always ask Linus to do the fixup, but 
generally he prefers to have this sorted out by the maintainers if it is 
detected by linux-next.

Paolo

> From: Stephen Rothwell <[email-masked]>
> Date: Thu, 22 Feb 2024 22:31:22 +1100
> Subject: [PATCH] fix up for "arm64/sysreg: Add register fields for ID_AA64DFR1_EL1"
> 
> interacting with "KVM: arm64: Snapshot all non-zero RES0/RES1 sysreg fields for later checking"
> 
> Signed-off-by: Stephen Rothwell <[email-masked]>
> ---
>   arch/arm64/kvm/check-res-bits.h | 1 -
>   1 file changed, 1 deletion(-)
> 
> diff --git a/arch/arm64/kvm/check-res-bits.h b/arch/arm64/kvm/check-res-bits.h
> index 967b5d171d53..39f537875d17 100644
> --- a/arch/arm64/kvm/check-res-bits.h
> +++ b/arch/arm64/kvm/check-res-bits.h
> @@ -55,7 +55,6 @@ static inline void check_res_bits(void)
>   	BUILD_BUG_ON(ID_AA64SMFR0_EL1_RES0	!= (GENMASK_ULL(62, 61) | GENMASK_ULL(51, 49) | GENMASK_ULL(31, 31) | GENMASK_ULL(27, 0)));
>   	BUILD_BUG_ON(ID_AA64FPFR0_EL1_RES0	!= (GENMASK_ULL(63, 32) | GENMASK_ULL(27, 2)));
>   	BUILD_BUG_ON(ID_AA64DFR0_EL1_RES0	!= (GENMASK_ULL(27, 24) | GENMASK_ULL(19, 16)));
> -	BUILD_BUG_ON(ID_AA64DFR1_EL1_RES0	!= (GENMASK_ULL(63, 0)));
>   	BUILD_BUG_ON(ID_AA64AFR0_EL1_RES0	!= (GENMASK_ULL(63, 32)));
>   	BUILD_BUG_ON(ID_AA64AFR1_EL1_RES0	!= (GENMASK_ULL(63, 0)));
>   	BUILD_BUG_ON(ID_AA64ISAR0_EL1_RES0	!= (GENMASK_ULL(3, 0)));