linux-kernel - Re: [PATCH v2] KVM: PPC: Book3S HV: Refactor HFSCR emulation for KVM guests

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <d6edb26f-f19e-4296-8fea-07961ce24960@linux.ibm.com>
Date: Thu, 18 Jul 2024 09:21:13 +0530
From: Madhavan Srinivasan <maddy@...ux.ibm.com>
To: Gautam Menghani <gautam@...ux.ibm.com>, mpe@...erman.id.au,
        npiggin@...il.com, christophe.leroy@...roup.eu,
        naveen.n.rao@...ux.ibm.com
Cc: linuxppc-dev@...ts.ozlabs.org, linux-kernel@...r.kernel.org,
        kvm@...r.kernel.org
Subject: Re: [PATCH v2] KVM: PPC: Book3S HV: Refactor HFSCR emulation for KVM
 guests


On 7/16/24 5:22 PM, Gautam Menghani wrote:
> Refactor HFSCR emulation for KVM guests when they exit out with
> H_FAC_UNAVAIL to use a switch case instead of checking all "cause"
> values, since the "cause" values are mutually exclusive; and this is
> better expressed with a switch case.
>
> Signed-off-by: Gautam Menghani <gautam@...ux.ibm.com>
> ---
> V1 -> V2:
> 1. Reword changelog to point out mutual exclusivity of HFSCR bits.
> 2. Reword commit message to match other commits in book3s_hv.c


Minor: I guess you mean "Reword the subject line"

Reviewed-by: Madhavan Srinivasan <maddy@...ux.ibm.com>



>
>   arch/powerpc/kvm/book3s_hv.c | 16 ++++++++++++----
>   1 file changed, 12 insertions(+), 4 deletions(-)
>
> diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
> index daaf7faf21a5..50797b0611a2 100644
> --- a/arch/powerpc/kvm/book3s_hv.c
> +++ b/arch/powerpc/kvm/book3s_hv.c
> @@ -1922,14 +1922,22 @@ static int kvmppc_handle_exit_hv(struct kvm_vcpu *vcpu,
>   
>   		r = EMULATE_FAIL;
>   		if (cpu_has_feature(CPU_FTR_ARCH_300)) {
> -			if (cause == FSCR_MSGP_LG)
> +			switch (cause) {
> +			case FSCR_MSGP_LG:
>   				r = kvmppc_emulate_doorbell_instr(vcpu);
> -			if (cause == FSCR_PM_LG)
> +				break;
> +			case FSCR_PM_LG:
>   				r = kvmppc_pmu_unavailable(vcpu);
> -			if (cause == FSCR_EBB_LG)
> +				break;
> +			case FSCR_EBB_LG:
>   				r = kvmppc_ebb_unavailable(vcpu);
> -			if (cause == FSCR_TM_LG)
> +				break;
> +			case FSCR_TM_LG:
>   				r = kvmppc_tm_unavailable(vcpu);
> +				break;
> +			default:
> +				break;
> +			}
>   		}
>   		if (r == EMULATE_FAIL) {
>   			kvmppc_core_queue_program(vcpu, SRR1_PROGILL |