2022-10-21 02:42:32

by Rafael Mendonca

[permalink] [raw]
Subject: [PATCH] x86/kvm: Remove unused virt to phys translation in kvm_guest_cpu_init()

Presumably, this was introduced due to a conflict resolution with
commit ef68017eb570 ("x86/kvm: Handle async page faults directly through
do_page_fault()"), given that the last posted version [1] of the blamed
commit was not based on the aforementioned commit.

[1] https://lore.kernel.org/kvm/[email protected]/

Fixes: b1d405751cd5 ("KVM: x86: Switch KVM guest to using interrupts for page ready APF delivery")
Signed-off-by: Rafael Mendonca <[email protected]>
---
arch/x86/kernel/kvm.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
index d4e48b4a438b..cf886f86038a 100644
--- a/arch/x86/kernel/kvm.c
+++ b/arch/x86/kernel/kvm.c
@@ -349,7 +349,7 @@ static notrace void kvm_guest_apic_eoi_write(u32 reg, u32 val)
static void kvm_guest_cpu_init(void)
{
if (kvm_para_has_feature(KVM_FEATURE_ASYNC_PF_INT) && kvmapf) {
- u64 pa = slow_virt_to_phys(this_cpu_ptr(&apf_reason));
+ u64 pa;

WARN_ON_ONCE(!static_branch_likely(&kvm_async_pf_enabled));

--
2.34.1


2022-10-21 12:21:04

by Vitaly Kuznetsov

[permalink] [raw]
Subject: Re: [PATCH] x86/kvm: Remove unused virt to phys translation in kvm_guest_cpu_init()

Rafael Mendonca <[email protected]> writes:

> Presumably, this was introduced due to a conflict resolution with
> commit ef68017eb570 ("x86/kvm: Handle async page faults directly through
> do_page_fault()"), given that the last posted version [1] of the blamed
> commit was not based on the aforementioned commit.
>
> [1] https://lore.kernel.org/kvm/[email protected]/
>
> Fixes: b1d405751cd5 ("KVM: x86: Switch KVM guest to using interrupts for page ready APF delivery")

Indeed, this looks like a mid-air collision happened upon commit/merge.

> Signed-off-by: Rafael Mendonca <[email protected]>
> ---
> arch/x86/kernel/kvm.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
> index d4e48b4a438b..cf886f86038a 100644
> --- a/arch/x86/kernel/kvm.c
> +++ b/arch/x86/kernel/kvm.c
> @@ -349,7 +349,7 @@ static notrace void kvm_guest_apic_eoi_write(u32 reg, u32 val)
> static void kvm_guest_cpu_init(void)
> {
> if (kvm_para_has_feature(KVM_FEATURE_ASYNC_PF_INT) && kvmapf) {
> - u64 pa = slow_virt_to_phys(this_cpu_ptr(&apf_reason));
> + u64 pa;
>
> WARN_ON_ONCE(!static_branch_likely(&kvm_async_pf_enabled));

Reviewed-by: Vitaly Kuznetsov <[email protected]>

--
Vitaly