From: Gerd Hoffmann <kraxel@redhat.com>
To: kvm@vger.kernel.org
Cc: Gerd Hoffmann <kraxel@redhat.com>,
Sean Christopherson <seanjc@google.com>,
Paolo Bonzini <pbonzini@redhat.com>,
Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
Dave Hansen <dave.hansen@linux.intel.com>,
x86@kernel.org (maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)),
"H. Peter Anvin" <hpa@zytor.com>,
linux-kernel@vger.kernel.org (open list:X86 ARCHITECTURE (32-BIT
AND 64-BIT))
Subject: [PATCH 3/3] kvm/svm: limit guest_phys_bits to 48 in 4-level paging mode
Date: Fri, 1 Mar 2024 11:14:09 +0100 [thread overview]
Message-ID: <20240301101410.356007-4-kraxel@redhat.com> (raw)
In-Reply-To: <20240301101410.356007-1-kraxel@redhat.com>
If the host runs in 4-level paging mode NPT is restricted to 4 paging
levels too. Adjust kvm_caps.guest_phys_bits accordingly.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
---
arch/x86/kvm/svm/svm.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index e90b429c84f1..8c3e2e3bd468 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -5229,6 +5229,11 @@ static __init int svm_hardware_setup(void)
get_npt_level(), PG_LEVEL_1G);
pr_info("Nested Paging %sabled\n", npt_enabled ? "en" : "dis");
+ if (npt_enabled &&
+ get_npt_level() == PT64_ROOT_4LEVEL &&
+ kvm_caps.guest_phys_bits > 48)
+ kvm_caps.guest_phys_bits = 48;
+
/* Setup shadow_me_value and shadow_me_mask */
kvm_mmu_set_me_spte_mask(sme_me_mask, sme_me_mask);
--
2.44.0
prev parent reply other threads:[~2024-03-01 10:14 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20240301101410.356007-1-kraxel@redhat.com>
2024-03-01 10:14 ` [PATCH 1/3] kvm: wire up KVM_CAP_VM_GPA_BITS for x86 Gerd Hoffmann
2024-03-01 16:13 ` Tao Su
2024-03-04 8:43 ` Gerd Hoffmann
2024-03-04 8:59 ` Tao Su
2024-03-04 11:47 ` Gerd Hoffmann
2024-03-04 15:15 ` Sean Christopherson
2024-03-05 2:59 ` Xiaoyao Li
2024-03-01 10:14 ` [PATCH 2/3] kvm/vmx: limit guest_phys_bits to 48 without 5-level ept Gerd Hoffmann
2024-03-01 10:14 ` Gerd Hoffmann [this message]
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