| Message ID | 20230214184606.510551-1-mizhang@google.com |
|---|---|
| Headers | show |
| Series | Overhauling amx_test | expand |
On Tue, Feb 14, 2023 at 6:46 PM Mingwei Zhang <mizhang@google.com> wrote: > > Add check of CR0.TS[bit 3] before the check of IA32_XFD_ERR in the #NM > handler in amx_test. This is because XFD may not be the only reason of > the IA32_XFD MSR and the bitmap corresponding to the state components > required by the faulting instruction." (Intel SDM vol 1. Section 13.14) > > Add the missing check of CR0.TS. > > Signed-off-by: Mingwei Zhang <mizhang@google.com> > --- > tools/testing/selftests/kvm/x86_64/amx_test.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/tools/testing/selftests/kvm/x86_64/amx_test.c b/tools/testing/selftests/kvm/x86_64/amx_test.c > index aac727ff7cf8..847752998660 100644 > --- a/tools/testing/selftests/kvm/x86_64/amx_test.c > +++ b/tools/testing/selftests/kvm/x86_64/amx_test.c > @@ -215,6 +215,7 @@ void guest_nm_handler(struct ex_regs *regs) > { > /* Check if #NM is triggered by XFEATURE_MASK_XTILEDATA */ > GUEST_SYNC(7); > + GUEST_ASSERT((get_cr0() & X86_CR0_TS) == 0); Can't we infer that the #NM is the result of an XFD error due to the fact that IA32_XFD_ERR is set? Is this check needed? SDM vol 1, 13.14, EXTENDED FEATURE DISABLE (XFD) - Device-not-available exceptions that are not due to XFD - those resulting from setting CR0.TS to 1 - do not modify the IA32_XFD_ERR MSR. > GUEST_ASSERT(rdmsr(MSR_IA32_XFD_ERR) == XFEATURE_MASK_XTILEDATA); > GUEST_SYNC(8); > GUEST_ASSERT(rdmsr(MSR_IA32_XFD_ERR) == XFEATURE_MASK_XTILEDATA); > -- > 2.39.1.581.gbfd45094c4-goog >
On Tue, Feb 14, 2023 at 6:46 PM Mingwei Zhang <mizhang@google.com> wrote: > > AMX architecture involves several entities such as xstate, XCR0, > IA32_XFD. This series add several missing checks on top of the existing > amx_test. > > v1 -> v2: > - Add a working xstate data structure suggested by seanjc. > - Split the checking of CR0.TS from the checking of XFD. > - Fix all the issues pointed by in review. > > v1: > https://lore.kernel.org/all/20230110185823.1856951-1-mizhang@google.com/ > > Mingwei Zhang (7): > KVM: selftests: x86: Fix an error in comment of amx_test > KVM: selftests: x86: Add a working xstate data structure > KVM: selftests: x86: Add check of CR0.TS in the #NM handler in > amx_test > KVM: selftests: Add the XFD check to IA32_XFD in #NM handler > KVM: selftests: Fix the checks to XFD_ERR using and operation > KVM: selftests: x86: Enable checking on xcomp_bv in amx_test > KVM: selftests: x86: Repeat the checking of xheader when > IA32_XFD[XTILEDATA] is set in amx_test > > .../selftests/kvm/include/x86_64/processor.h | 12 ++++ > tools/testing/selftests/kvm/x86_64/amx_test.c | 59 ++++++++++--------- > 2 files changed, 43 insertions(+), 28 deletions(-) > > -- > 2.39.1.581.gbfd45094c4-goog > Would you be open to adding my series to the end of this one? That way we have one series that's overhauling amx_test. https://lore.kernel.org/kvm/20230217215959.1569092-1-aaronlewis@google.com/
On Fri, Feb 17, 2023, Aaron Lewis wrote: > On Tue, Feb 14, 2023 at 6:46 PM Mingwei Zhang <mizhang@google.com> wrote: > > > > Add check of CR0.TS[bit 3] before the check of IA32_XFD_ERR in the #NM > > handler in amx_test. This is because XFD may not be the only reason of > > the IA32_XFD MSR and the bitmap corresponding to the state components > > required by the faulting instruction." (Intel SDM vol 1. Section 13.14) > > > > Add the missing check of CR0.TS. > > > > Signed-off-by: Mingwei Zhang <mizhang@google.com> > > --- > > tools/testing/selftests/kvm/x86_64/amx_test.c | 1 + > > 1 file changed, 1 insertion(+) > > > > diff --git a/tools/testing/selftests/kvm/x86_64/amx_test.c b/tools/testing/selftests/kvm/x86_64/amx_test.c > > index aac727ff7cf8..847752998660 100644 > > --- a/tools/testing/selftests/kvm/x86_64/amx_test.c > > +++ b/tools/testing/selftests/kvm/x86_64/amx_test.c > > @@ -215,6 +215,7 @@ void guest_nm_handler(struct ex_regs *regs) > > { > > /* Check if #NM is triggered by XFEATURE_MASK_XTILEDATA */ > > GUEST_SYNC(7); > > + GUEST_ASSERT((get_cr0() & X86_CR0_TS) == 0); > > Can't we infer that the #NM is the result of an XFD error due to the fact > that IA32_XFD_ERR is set? Is this check needed? > SDM vol 1, 13.14, EXTENDED FEATURE DISABLE (XFD) > - Device-not-available exceptions that are not due to XFD - those > resulting from setting CR0.TS to 1 - do not modify the IA32_XFD_ERR > MSR. > We don't infer from the reasons of #NM and that is the purpose of this selftest. Yes, this looks a little bit pedantic. But still, it is worth adding the check since violation of that indicates either 1) the selftest mistakenly did not clear XFD_ERR prior to #NM or 2) hardware is broken. > > GUEST_ASSERT(rdmsr(MSR_IA32_XFD_ERR) == XFEATURE_MASK_XTILEDATA); > > GUEST_SYNC(8); > > GUEST_ASSERT(rdmsr(MSR_IA32_XFD_ERR) == XFEATURE_MASK_XTILEDATA); > > -- > > 2.39.1.581.gbfd45094c4-goog > >
On Fri, Feb 17, 2023, Aaron Lewis wrote: > On Tue, Feb 14, 2023 at 6:46 PM Mingwei Zhang <mizhang@google.com> wrote: > > > > AMX architecture involves several entities such as xstate, XCR0, > > IA32_XFD. This series add several missing checks on top of the existing > > amx_test. > > > > v1 -> v2: > > - Add a working xstate data structure suggested by seanjc. > > - Split the checking of CR0.TS from the checking of XFD. > > - Fix all the issues pointed by in review. > > > > v1: > > https://lore.kernel.org/all/20230110185823.1856951-1-mizhang@google.com/ > > > > Mingwei Zhang (7): > > KVM: selftests: x86: Fix an error in comment of amx_test > > KVM: selftests: x86: Add a working xstate data structure > > KVM: selftests: x86: Add check of CR0.TS in the #NM handler in > > amx_test > > KVM: selftests: Add the XFD check to IA32_XFD in #NM handler > > KVM: selftests: Fix the checks to XFD_ERR using and operation > > KVM: selftests: x86: Enable checking on xcomp_bv in amx_test > > KVM: selftests: x86: Repeat the checking of xheader when > > IA32_XFD[XTILEDATA] is set in amx_test > > > > .../selftests/kvm/include/x86_64/processor.h | 12 ++++ > > tools/testing/selftests/kvm/x86_64/amx_test.c | 59 ++++++++++--------- > > 2 files changed, 43 insertions(+), 28 deletions(-) > > > > -- > > 2.39.1.581.gbfd45094c4-goog > > > > Would you be open to adding my series to the end of this one? That > way we have one series that's overhauling amx_test. > > https://lore.kernel.org/kvm/20230217215959.1569092-1-aaronlewis@google.com/ Sure, I will integrate your changes into this series.
On Tue, Feb 14, 2023 at 06:46:00PM +0000, Mingwei Zhang wrote: >- /* xsave data for guest_code */ >- xsavedata = vm_vaddr_alloc_pages(vm, 3); >- memset(addr_gva2hva(vm, xsavedata), 0, 3 * getpagesize()); >- vcpu_args_set(vcpu, 3, amx_cfg, tiledata, xsavedata); >+ /* XSAVE state for guest_code */ >+ xstate = vm_vaddr_alloc_pages(vm, DIV_ROUND_UP(XSAVE_SIZE, PAGE_SIZE)); >+ memset(addr_gva2hva(vm, xstate), 0, DIV_ROUND_UP(XSAVE_SIZE, PAGE_SIZE)); ^ this should be the size in bytes instead of in pages. Right?
On Sun, Feb 19, 2023 at 12:33 AM Chao Gao <chao.gao@intel.com> wrote: > > On Tue, Feb 14, 2023 at 06:46:00PM +0000, Mingwei Zhang wrote: > >- /* xsave data for guest_code */ > >- xsavedata = vm_vaddr_alloc_pages(vm, 3); > >- memset(addr_gva2hva(vm, xsavedata), 0, 3 * getpagesize()); > >- vcpu_args_set(vcpu, 3, amx_cfg, tiledata, xsavedata); > >+ /* XSAVE state for guest_code */ > >+ xstate = vm_vaddr_alloc_pages(vm, DIV_ROUND_UP(XSAVE_SIZE, PAGE_SIZE)); > >+ memset(addr_gva2hva(vm, xstate), 0, DIV_ROUND_UP(XSAVE_SIZE, PAGE_SIZE)); > > ^ this should be the size in bytes instead of in pages. Right? Right, thanks for catching that. I will fix it in the next version.
AMX architecture involves several entities such as xstate, XCR0, IA32_XFD. This series add several missing checks on top of the existing amx_test. v1 -> v2: - Add a working xstate data structure suggested by seanjc. - Split the checking of CR0.TS from the checking of XFD. - Fix all the issues pointed by in review. v1: https://lore.kernel.org/all/20230110185823.1856951-1-mizhang@google.com/ Mingwei Zhang (7): KVM: selftests: x86: Fix an error in comment of amx_test KVM: selftests: x86: Add a working xstate data structure KVM: selftests: x86: Add check of CR0.TS in the #NM handler in amx_test KVM: selftests: Add the XFD check to IA32_XFD in #NM handler KVM: selftests: Fix the checks to XFD_ERR using and operation KVM: selftests: x86: Enable checking on xcomp_bv in amx_test KVM: selftests: x86: Repeat the checking of xheader when IA32_XFD[XTILEDATA] is set in amx_test .../selftests/kvm/include/x86_64/processor.h | 12 ++++ tools/testing/selftests/kvm/x86_64/amx_test.c | 59 ++++++++++--------- 2 files changed, 43 insertions(+), 28 deletions(-)