Re: [PATCH] KVM: SVM: Fix a misplaced paranthesis in APICV inhibit mask generation

From: Maxim Levitsky
Date: Sat Jun 11 2022 - 09:44:21 EST


On Fri, 2022-06-10 at 19:18 +0000, Sean Christopherson wrote:
> Relocate a ")" to its proper place at the end of a BIT usage, the intent
> is most definitely not to have a feedback loop of BITs in the mask.
>
> arch/x86/kvm/svm/avic.c: In function ‘avic_check_apicv_inhibit_reasons’:
> include/vdso/bits.h:7:40: error: left shift count >= width of type [-Werror=shift-count-overflow]
> 7 | #define BIT(nr) (UL(1) << (nr))
> | ^~
> arch/x86/kvm/svm/avic.c:911:27: note: in expansion of macro ‘BIT’
> 911 | BIT(APICV_INHIBIT_REASON_SEV |
> | ^~~
>
> Fixes: 3743c2f02517 ("KVM: x86: inhibit APICv/AVIC on changes to APIC ID or APIC base")
> Cc: Maxim Levitsky <mlevitsk@xxxxxxxxxx>
> Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
> ---
> arch/x86/kvm/svm/avic.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/arch/x86/kvm/svm/avic.c b/arch/x86/kvm/svm/avic.c
> index 5542d8959e11..d1bc5820ea46 100644
> --- a/arch/x86/kvm/svm/avic.c
> +++ b/arch/x86/kvm/svm/avic.c
> @@ -908,9 +908,9 @@ bool avic_check_apicv_inhibit_reasons(enum kvm_apicv_inhibit reason)
> BIT(APICV_INHIBIT_REASON_PIT_REINJ) |
> BIT(APICV_INHIBIT_REASON_X2APIC) |
> BIT(APICV_INHIBIT_REASON_BLOCKIRQ) |
> - BIT(APICV_INHIBIT_REASON_SEV |
> + BIT(APICV_INHIBIT_REASON_SEV) |
> BIT(APICV_INHIBIT_REASON_APIC_ID_MODIFIED) |
> - BIT(APICV_INHIBIT_REASON_APIC_BASE_MODIFIED));
> + BIT(APICV_INHIBIT_REASON_APIC_BASE_MODIFIED);
>
> return supported & BIT(reason);
> }
>
> base-commit: b23f8810c46978bc05252db03055a61fcadc07d5

Sorry about it!

Best regards,
Maxim Levitsky