linux-kernel - [PATCH v2 2/8] KVM: VMX: Refactor 32-bit PSE PT creation to avoid using MMU macro

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: <20220614233328.3896033-3-seanjc@google.com>
Date:   Tue, 14 Jun 2022 23:33:22 +0000
From:   Sean Christopherson <seanjc@...gle.com>
To:     Paolo Bonzini <pbonzini@...hat.com>
Cc:     Sean Christopherson <seanjc@...gle.com>,
        Vitaly Kuznetsov <vkuznets@...hat.com>,
        Wanpeng Li <wanpengli@...cent.com>,
        Jim Mattson <jmattson@...gle.com>,
        Joerg Roedel <joro@...tes.org>, kvm@...r.kernel.org,
        linux-kernel@...r.kernel.org,
        Lai Jiangshan <jiangshan.ljs@...group.com>
Subject: [PATCH v2 2/8] KVM: VMX: Refactor 32-bit PSE PT creation to avoid
 using MMU macro

Compute the number of PTEs to be filled for the 32-bit PSE page tables
using the page size and the size of each entry.  While using the MMU's
PT32_ENT_PER_PAGE macro is arguably better in isolation, removing VMX's
usage will allow a future namespacing cleanup to move the guest page
table macros into paging_tmpl.h, out of the reach of code that isn't
directly related to shadow paging.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@...gle.com>
---
 arch/x86/kvm/vmx/vmx.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 5e14e4c40007..b774f8c1b952 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -3704,7 +3704,7 @@ static int init_rmode_identity_map(struct kvm *kvm)
 	}
 
 	/* Set up identity-mapping pagetable for EPT in real mode */
-	for (i = 0; i < PT32_ENT_PER_PAGE; i++) {
+	for (i = 0; i < (PAGE_SIZE / sizeof(tmp)); i++) {
 		tmp = (i << 22) + (_PAGE_PRESENT | _PAGE_RW | _PAGE_USER |
 			_PAGE_ACCESSED | _PAGE_DIRTY | _PAGE_PSE);
 		if (__copy_to_user(uaddr + i * sizeof(tmp), &tmp, sizeof(tmp))) {
-- 
2.36.1.476.g0c4daa206d-goog