linux-kernel - [PATCH v2 22/23] KVM: selftests: Set the user bit on nested MMU PTEs

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: <20251021074736.1324328-23-yosry.ahmed@linux.dev>
Date: Tue, 21 Oct 2025 07:47:35 +0000
From: Yosry Ahmed <yosry.ahmed@...ux.dev>
To: Sean Christopherson <seanjc@...gle.com>
Cc: Paolo Bonzini <pbonzini@...hat.com>,
	Jim Mattson <jmattson@...gle.com>,
	kvm@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	Yosry Ahmed <yosry.ahmed@...ux.dev>
Subject: [PATCH v2 22/23] KVM: selftests: Set the user bit on nested MMU PTEs

Similar to KVM's shadow MMU (in most cases), set the user bit on nested
PTEs. This is in preparation for supporting NPT mappings, which require
the user bit to be set. This should be nop for VMX.

Signed-off-by: Yosry Ahmed <yosry.ahmed@...ux.dev>
---
 tools/testing/selftests/kvm/lib/x86/processor.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/kvm/lib/x86/processor.c b/tools/testing/selftests/kvm/lib/x86/processor.c
index 958389ec1722d..c2912b0a49e90 100644
--- a/tools/testing/selftests/kvm/lib/x86/processor.c
+++ b/tools/testing/selftests/kvm/lib/x86/processor.c
@@ -211,7 +211,7 @@ static uint64_t *virt_create_upper_pte(struct kvm_vm *vm,
 	paddr = vm_untag_gpa(vm, paddr);
 
 	if (!(*pte & masks->present)) {
-		*pte = masks->present | masks->writeable | masks->x;
+		*pte = masks->present | masks->writeable | masks->x | masks->user;
 		if (current_level == target_level)
 			*pte |= masks->large | (paddr & PHYSICAL_PAGE_MASK);
 		else
@@ -276,7 +276,7 @@ void __virt_pg_map(struct kvm_vm *vm, vm_paddr_t root_gpa, uint64_t vaddr,
 	pte = virt_get_pte(vm, root_gpa, pte, vaddr, PG_LEVEL_4K, masks);
 	TEST_ASSERT(!(*pte & masks->present),
 		    "PTE already present for 4k page at vaddr: 0x%lx", vaddr);
-	*pte = masks->present | masks->writeable | masks->x
+	*pte = masks->present | masks->writeable | masks->x | masks->user
 		| (paddr & PHYSICAL_PAGE_MASK);
 
 	/*
-- 
2.51.0.869.ge66316f041-goog