linux-kernel - [PATCH 5.12 301/700] KVM: x86/mmu: Drop redundant trace_kvm_mmu_set

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 for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20210712061008.399846592@linuxfoundation.org>
Date:   Mon, 12 Jul 2021 08:06:24 +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 5.12 301/700] KVM: x86/mmu: Drop redundant trace_kvm_mmu_set_spte() in the TDP MMU

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

[ Upstream commit 3849e0924ef14a245aa292ecaa9accdc4792012c ]

Remove TDP MMU's call to trace_kvm_mmu_set_spte() that is done for both
shadow-present SPTEs and MMIO SPTEs.  It's fully redundant for the
former, and unnecessary for the latter.  This aligns TDP MMU tracing
behavior with that of the legacy MMU.

Fixes: 33dd3574f5fe ("kvm: x86/mmu: Add existing trace points to TDP MMU")
Cc: Ben Gardon <bgardon@...gle.com>
Signed-off-by: Sean Christopherson <seanjc@...gle.com>
Message-Id: <20210225204749.1512652-9-seanjc@...gle.com>
Signed-off-by: Paolo Bonzini <pbonzini@...hat.com>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 arch/x86/kvm/mmu/tdp_mmu.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
index 0aca7dcbcbf9..7cfb55788df5 100644
--- a/arch/x86/kvm/mmu/tdp_mmu.c
+++ b/arch/x86/kvm/mmu/tdp_mmu.c
@@ -777,12 +777,11 @@ static int tdp_mmu_map_handle_target_level(struct kvm_vcpu *vcpu, int write,
 		trace_mark_mmio_spte(rcu_dereference(iter->sptep), iter->gfn,
 				     new_spte);
 		ret = RET_PF_EMULATE;
-	} else
+	} else {
 		trace_kvm_mmu_set_spte(iter->level, iter->gfn,
 				       rcu_dereference(iter->sptep));
+	}
 
-	trace_kvm_mmu_set_spte(iter->level, iter->gfn,
-			       rcu_dereference(iter->sptep));
 	if (!prefault)
 		vcpu->stat.pf_fixed++;
 
-- 
2.30.2