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: <20210412084016.576312582@linuxfoundation.org>
Date:   Mon, 12 Apr 2021 10:40:02 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Ben Gardon <bgardon@...gle.com>,
        Sean Christopherson <seanjc@...gle.com>,
        Paolo Bonzini <pbonzini@...hat.com>,
        Sasha Levin <sashal@...nel.org>
Subject: [PATCH 5.10 088/188] KVM: x86/mmu: Ensure TLBs are flushed for TDP MMU during NX zapping

From: Sean Christopherson <seanjc@...gle.com>

[ Upstream commit 048f49809c526348775425420fb5b8e84fd9a133 ]

Honor the "flush needed" return from kvm_tdp_mmu_zap_gfn_range(), which
does the flush itself if and only if it yields (which it will never do in
this particular scenario), and otherwise expects the caller to do the
flush.  If pages are zapped from the TDP MMU but not the legacy MMU, then
no flush will occur.

Fixes: 29cf0f5007a2 ("kvm: x86/mmu: NX largepage recovery for TDP MMU")
Cc: stable@...r.kernel.org
Cc: Ben Gardon <bgardon@...gle.com>
Signed-off-by: Sean Christopherson <seanjc@...gle.com>
Message-Id: <20210325200119.1359384-3-seanjc@...gle.com>
Reviewed-by: Ben Gardon <bgardon@...gle.com>
Signed-off-by: Paolo Bonzini <pbonzini@...hat.com>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 arch/x86/kvm/mmu/mmu.c | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index dacbd13d32c6..354f9926a183 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -5972,6 +5972,8 @@ static void kvm_recover_nx_lpages(struct kvm *kvm)
 	struct kvm_mmu_page *sp;
 	unsigned int ratio;
 	LIST_HEAD(invalid_list);
+	bool flush = false;
+	gfn_t gfn_end;
 	ulong to_zap;
 
 	rcu_idx = srcu_read_lock(&kvm->srcu);
@@ -5993,19 +5995,20 @@ static void kvm_recover_nx_lpages(struct kvm *kvm)
 				      lpage_disallowed_link);
 		WARN_ON_ONCE(!sp->lpage_disallowed);
 		if (sp->tdp_mmu_page)
-			kvm_tdp_mmu_zap_gfn_range(kvm, sp->gfn,
-				sp->gfn + KVM_PAGES_PER_HPAGE(sp->role.level));
-		else {
+			gfn_end = sp->gfn + KVM_PAGES_PER_HPAGE(sp->role.level);
+			flush = kvm_tdp_mmu_zap_gfn_range(kvm, sp->gfn, gfn_end);
+		} else {
 			kvm_mmu_prepare_zap_page(kvm, sp, &invalid_list);
 			WARN_ON_ONCE(sp->lpage_disallowed);
 		}
 
 		if (need_resched() || spin_needbreak(&kvm->mmu_lock)) {
-			kvm_mmu_commit_zap_page(kvm, &invalid_list);
+			kvm_mmu_remote_flush_or_zap(kvm, &invalid_list, flush);
 			cond_resched_lock(&kvm->mmu_lock);
+			flush = false;
 		}
 	}
-	kvm_mmu_commit_zap_page(kvm, &invalid_list);
+	kvm_mmu_remote_flush_or_zap(kvm, &invalid_list, flush);
 
 	spin_unlock(&kvm->mmu_lock);
 	srcu_read_unlock(&kvm->srcu, rcu_idx);
-- 
2.30.2



Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ