[PATCH v3 14/41] KVM: PPC: Book3S 64: move bad_host_intr check to HV handler

[Alexey Kardashevskiy]

On 06/03/2021 02:06, Nicholas Piggin wrote:
> This is not used by PR KVM.
> 
> Signed-off-by: Nicholas Piggin <npiggin at gmail.com>


Reviewed-by: Alexey Kardashevskiy <aik at ozlabs.ru>

a small tote - it probably makes sense to move this before 09/41 as this 
one removes what 09/41 added to book3s_64_entry.S. Thanks,


> ---
>   arch/powerpc/kvm/book3s_64_entry.S      | 3 ---
>   arch/powerpc/kvm/book3s_hv_rmhandlers.S | 4 +++-
>   arch/powerpc/kvm/book3s_segment.S       | 7 +++++++
>   3 files changed, 10 insertions(+), 4 deletions(-)
> 
> diff --git a/arch/powerpc/kvm/book3s_64_entry.S b/arch/powerpc/kvm/book3s_64_entry.S
> index d06e81842368..7a6b060ceed8 100644
> --- a/arch/powerpc/kvm/book3s_64_entry.S
> +++ b/arch/powerpc/kvm/book3s_64_entry.S
> @@ -78,11 +78,8 @@ do_kvm_interrupt:
>   	beq-	.Lmaybe_skip
>   .Lno_skip:
>   #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
> -	cmpwi	r9,KVM_GUEST_MODE_HOST_HV
> -	beq	kvmppc_bad_host_intr
>   #ifdef CONFIG_KVM_BOOK3S_PR_POSSIBLE
>   	cmpwi	r9,KVM_GUEST_MODE_GUEST
> -	ld	r9,HSTATE_SCRATCH2(r13)
>   	beq	kvmppc_interrupt_pr
>   #endif
>   	b	kvmppc_interrupt_hv
> diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
> index f976efb7e4a9..75405ef53238 100644
> --- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
> +++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
> @@ -1265,6 +1265,7 @@ hdec_soon:
>   kvmppc_interrupt_hv:
>   	/*
>   	 * Register contents:
> +	 * R9		= HSTATE_IN_GUEST
>   	 * R12		= (guest CR << 32) | interrupt vector
>   	 * R13		= PACA
>   	 * guest R12 saved in shadow VCPU SCRATCH0
> @@ -1272,6 +1273,8 @@ kvmppc_interrupt_hv:
>   	 * guest R9 saved in HSTATE_SCRATCH2
>   	 */
>   	/* We're now back in the host but in guest MMU context */
> +	cmpwi	r9,KVM_GUEST_MODE_HOST_HV
> +	beq	kvmppc_bad_host_intr
>   	li	r9, KVM_GUEST_MODE_HOST_HV
>   	stb	r9, HSTATE_IN_GUEST(r13)
>   
> @@ -3272,7 +3275,6 @@ END_FTR_SECTION_IFCLR(CPU_FTR_P9_TM_HV_ASSIST)
>    * cfar is saved in HSTATE_CFAR(r13)
>    * ppr is saved in HSTATE_PPR(r13)
>    */
> -.global kvmppc_bad_host_intr
>   kvmppc_bad_host_intr:
>   	/*
>   	 * Switch to the emergency stack, but start half-way down in
> diff --git a/arch/powerpc/kvm/book3s_segment.S b/arch/powerpc/kvm/book3s_segment.S
> index 1f492aa4c8d6..ef1d88b869bf 100644
> --- a/arch/powerpc/kvm/book3s_segment.S
> +++ b/arch/powerpc/kvm/book3s_segment.S
> @@ -167,8 +167,15 @@ kvmppc_interrupt_pr:
>   	 * R12             = (guest CR << 32) | exit handler id
>   	 * R13             = PACA
>   	 * HSTATE.SCRATCH0 = guest R12
> +	 *
> +	 * If HV is possible, additionally:
> +	 * R9              = HSTATE_IN_GUEST
> +	 * HSTATE.SCRATCH2 = guest R9
>   	 */
>   #ifdef CONFIG_PPC64
> +#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
> +	ld	r9,HSTATE_SCRATCH2(r13)
> +#endif
>   	/* Match 32-bit entry */
>   	rotldi	r12, r12, 32		  /* Flip R12 halves for stw */
>   	stw	r12, HSTATE_SCRATCH1(r13) /* CR is now in the low half */
> 

-- 
Alexey