linux-kernel - Re: [PATCH v9 05/19] KVM: selftests: Update kvm_init_vm_address

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: <CAAhR5DHbhCaR53GuKotrmLqVDRBzc1zvLN1xX+U2iJT1gEdSbg@mail.gmail.com>
Date: Tue, 26 Aug 2025 11:04:54 -0500
From: Sagi Shahar <sagis@...gle.com>
To: Binbin Wu <binbin.wu@...ux.intel.com>
Cc: linux-kselftest@...r.kernel.org, Paolo Bonzini <pbonzini@...hat.com>, 
	Shuah Khan <shuah@...nel.org>, Sean Christopherson <seanjc@...gle.com>, 
	Ackerley Tng <ackerleytng@...gle.com>, Ryan Afranji <afranji@...gle.com>, 
	Andrew Jones <ajones@...tanamicro.com>, Isaku Yamahata <isaku.yamahata@...el.com>, 
	Erdem Aktas <erdemaktas@...gle.com>, Rick Edgecombe <rick.p.edgecombe@...el.com>, 
	Roger Wang <runanwang@...gle.com>, Oliver Upton <oliver.upton@...ux.dev>, 
	"Pratik R. Sampat" <pratikrajesh.sampat@....com>, Reinette Chatre <reinette.chatre@...el.com>, 
	Ira Weiny <ira.weiny@...el.com>, Chao Gao <chao.gao@...el.com>, 
	Chenyi Qiang <chenyi.qiang@...el.com>, linux-kernel@...r.kernel.org, kvm@...r.kernel.org, 
	Adrian Hunter <adrian.hunter@...el.com>
Subject: Re: [PATCH v9 05/19] KVM: selftests: Update kvm_init_vm_address_properties()
 for TDX

On Tue, Aug 26, 2025 at 12:51 AM Binbin Wu <binbin.wu@...ux.intel.com> wrote:
>
>
>
> On 8/21/2025 12:28 PM, Sagi Shahar wrote:
> > From: Isaku Yamahata <isaku.yamahata@...el.com>
> >
> > Let kvm_init_vm_address_properties() initialize vm->arch.{s_bit, tag_mask}
> > similar to SEV.
> >
> > TDX sets the shared bit based on the guest physical address width and
> > currently supports 48 and 52 widths.
> >
> > Co-developed-by: Adrian Hunter <adrian.hunter@...el.com>
> > Signed-off-by: Adrian Hunter <adrian.hunter@...el.com>
> > Signed-off-by: Isaku Yamahata <isaku.yamahata@...el.com>
> > Co-developed-by: Sagi Shahar <sagis@...gle.com>
> > Signed-off-by: Sagi Shahar <sagis@...gle.com>
> > ---
> >   .../selftests/kvm/include/x86/tdx/tdx_util.h       | 14 ++++++++++++++
> >   tools/testing/selftests/kvm/lib/x86/processor.c    | 12 ++++++++++--
> >   2 files changed, 24 insertions(+), 2 deletions(-)
> >   create mode 100644 tools/testing/selftests/kvm/include/x86/tdx/tdx_util.h
> >
> > diff --git a/tools/testing/selftests/kvm/include/x86/tdx/tdx_util.h b/tools/testing/selftests/kvm/include/x86/tdx/tdx_util.h
> > new file mode 100644
> > index 000000000000..286d5e3c24b1
> > --- /dev/null
> > +++ b/tools/testing/selftests/kvm/include/x86/tdx/tdx_util.h
> > @@ -0,0 +1,14 @@
> > +/* SPDX-License-Identifier: GPL-2.0-only */
> > +#ifndef SELFTESTS_TDX_TDX_UTIL_H
> > +#define SELFTESTS_TDX_TDX_UTIL_H
> > +
> > +#include <stdbool.h>
> > +
> > +#include "kvm_util.h"
> > +
> > +static inline bool is_tdx_vm(struct kvm_vm *vm)
> > +{
> > +     return vm->type == KVM_X86_TDX_VM;
> > +}
>
> If the branch "vm->type != KVM_X86_TDX_VM" in patch 04/19
> is still needed, this helper could be added earlier and used instead of
> open code.
>

I'm dropping the check in 04/19. See my response to Ira.

> > +
> > +#endif // SELFTESTS_TDX_TDX_UTIL_H
> > diff --git a/tools/testing/selftests/kvm/lib/x86/processor.c b/tools/testing/selftests/kvm/lib/x86/processor.c
> > index 1eae92957456..6dbf40cbbc2a 100644
> > --- a/tools/testing/selftests/kvm/lib/x86/processor.c
> > +++ b/tools/testing/selftests/kvm/lib/x86/processor.c
> > @@ -8,6 +8,7 @@
> >   #include "kvm_util.h"
> >   #include "processor.h"
> >   #include "sev.h"
> > +#include "tdx/tdx_util.h"
> >
> >   #ifndef NUM_INTERRUPTS
> >   #define NUM_INTERRUPTS 256
> > @@ -1190,12 +1191,19 @@ void kvm_get_cpu_address_width(unsigned int *pa_bits, unsigned int *va_bits)
> >
> >   void kvm_init_vm_address_properties(struct kvm_vm *vm)
> >   {
> > +     uint32_t gpa_bits = kvm_cpu_property(X86_PROPERTY_GUEST_MAX_PHY_ADDR);
> > +
> > +     vm->arch.sev_fd = -1;
> > +
> >       if (is_sev_vm(vm)) {
> >               vm->arch.sev_fd = open_sev_dev_path_or_exit();
> >               vm->arch.c_bit = BIT_ULL(this_cpu_property(X86_PROPERTY_SEV_C_BIT));
> >               vm->gpa_tag_mask = vm->arch.c_bit;
> > -     } else {
> > -             vm->arch.sev_fd = -1;
> > +     } else if (is_tdx_vm(vm)) {
> > +             TEST_ASSERT(gpa_bits == 48 || gpa_bits == 52,
> > +                         "TDX: bad X86_PROPERTY_GUEST_MAX_PHY_ADDR value: %u", gpa_bits);
> > +             vm->arch.s_bit = 1ULL << (gpa_bits - 1);
>
> Nit: Use BIT_ULL().
>

ACK, Will update in next version.

> > +             vm->gpa_tag_mask = vm->arch.s_bit;
> >       }
> >   }
> >
>