Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]
Groups > linux.kernel > #1364670
| From | Xiao Guangrong <guangrong.xiao@linux.intel.com> |
|---|---|
| Newsgroups | linux.kernel |
| Subject | Re: [PATCH 1/4] KVM: MMU: fix permission_fault() |
| Date | 2016-03-25 14:50 +0100 |
| Message-ID | <rgAhH-2m9-3@gated-at.bofh.it> (permalink) |
| References | <rgzYm-2fh-7@gated-at.bofh.it> <rgA82-2iN-5@gated-at.bofh.it> |
| Organization | linux.* mail to news gateway |
On 03/25/2016 09:35 PM, Paolo Bonzini wrote:
>
>
> On 25/03/2016 14:19, Xiao Guangrong wrote:
>> kvm-unit-tests complained about the PFEC is not set properly, e.g,:
>> test pte.rw pte.d pte.nx pde.p pde.rw pde.pse user fetch: FAIL: error code 15
>> expected 5
>> Dump mapping: address: 0x123400000000
>> ------L4: 3e95007
>> ------L3: 3e96007
>> ------L2: 2000083
>
> What's the command line for the reproducer?
QEMU=/home/eric/qemu/x86_64-softmmu/qemu-system-x86_64 ./x86-run x86/access.flat
>
>> diff --git a/arch/x86/kvm/mmu.h b/arch/x86/kvm/mmu.h
>> index b70df72..81bffd1 100644
>> --- a/arch/x86/kvm/mmu.h
>> +++ b/arch/x86/kvm/mmu.h
>> @@ -154,7 +154,7 @@ static inline u8 permission_fault(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
>> unsigned pfec)
>> {
>> int cpl = kvm_x86_ops->get_cpl(vcpu);
>> - unsigned long rflags = kvm_x86_ops->get_rflags(vcpu);
>> + unsigned long errcode, rflags = kvm_x86_ops->get_rflags(vcpu);
>>
>> /*
>> * If CPL < 3, SMAP prevention are disabled if EFLAGS.AC = 1.
>> @@ -175,7 +175,7 @@ static inline u8 permission_fault(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
>> bool fault = (mmu->permissions[index] >> pte_access) & 1;
>>
>> WARN_ON(pfec & (PFERR_PK_MASK | PFERR_RSVD_MASK));
>> - pfec |= PFERR_PRESENT_MASK;
>> + errcode = PFERR_PRESENT_MASK;
>
> So is this patch doing the same as "KVM: MMU: precompute page fault
> error code"? It was necessary after all. :)
Sorry for my mistake... I missed the logic you changed :(
I still prefer to calculating the error code on the fault path which is rare, or
think a way to encapsulate it to permission_fault()...
Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread
[PATCH 1/4] KVM: MMU: fix permission_fault() Xiao Guangrong <guangrong.xiao@linux.intel.com> - 2016-03-25 14:30 +0100
[PATCH 3/4] KVM: MMU: reduce the size of mmu_page_path Xiao Guangrong <guangrong.xiao@linux.intel.com> - 2016-03-25 14:30 +0100
Re: [PATCH 3/4] KVM: MMU: reduce the size of mmu_page_path Paolo Bonzini <pbonzini@redhat.com> - 2016-03-25 14:50 +0100
Re: [PATCH 3/4] KVM: MMU: reduce the size of mmu_page_path Paolo Bonzini <pbonzini@redhat.com> - 2016-03-25 15:00 +0100
Re: [PATCH 3/4] KVM: MMU: reduce the size of mmu_page_path Xiao Guangrong <guangrong.xiao@linux.intel.com> - 2016-03-25 15:10 +0100
Re: [PATCH 3/4] KVM: MMU: reduce the size of mmu_page_path Paolo Bonzini <pbonzini@redhat.com> - 2016-03-25 15:30 +0100
Re: [PATCH 3/4] KVM: MMU: reduce the size of mmu_page_path Xiao Guangrong <guangrong.xiao@linux.intel.com> - 2016-03-25 15:00 +0100
Re: [PATCH 1/4] KVM: MMU: fix permission_fault() Paolo Bonzini <pbonzini@redhat.com> - 2016-03-25 14:40 +0100
Re: [PATCH 1/4] KVM: MMU: fix permission_fault() Xiao Guangrong <guangrong.xiao@linux.intel.com> - 2016-03-25 14:50 +0100
Re: [PATCH 1/4] KVM: MMU: fix permission_fault() Paolo Bonzini <pbonzini@redhat.com> - 2016-03-25 15:00 +0100
[PATCH 2/4] KVM: MMU: simplify the logic of __mmu_unsync_walk() Xiao Guangrong <guangrong.xiao@linux.intel.com> - 2016-03-25 14:40 +0100
Re: [PATCH 1/4] KVM: MMU: fix permission_fault() Paolo Bonzini <pbonzini@redhat.com> - 2016-03-25 15:30 +0100
Re: [PATCH 1/4] KVM: MMU: fix permission_fault() Xiao Guangrong <guangrong.xiao@linux.intel.com> - 2016-03-29 19:50 +0200
Re: [PATCH 1/4] KVM: MMU: fix permission_fault() Paolo Bonzini <pbonzini@redhat.com> - 2016-03-29 22:20 +0200
Re: [PATCH 1/4] KVM: MMU: fix permission_fault() Xiao Guangrong <guangrong.xiao@linux.intel.com> - 2016-03-30 04:00 +0200
Re: [PATCH 1/4] KVM: MMU: fix permission_fault() Paolo Bonzini <pbonzini@redhat.com> - 2016-03-30 08:40 +0200
Re: [PATCH 1/4] KVM: MMU: fix permission_fault() Xiao Guangrong <guangrong.xiao@linux.intel.com> - 2016-03-30 08:50 +0200
csiph-web