linux-kernel - [PATCH 01/16] KVM: MMU: pass unadulterated gpa to direct_page

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Message-Id: <20210807134936.3083984-2-pbonzini@redhat.com>
Date:   Sat,  7 Aug 2021 09:49:21 -0400
From:   Paolo Bonzini <pbonzini@...hat.com>
To:     linux-kernel@...r.kernel.org, kvm@...r.kernel.org
Cc:     isaku.yamahata@...el.com, David Matlack <dmatlack@...gle.com>,
        seanjc@...gle.com, peterx@...hat.com
Subject: [PATCH 01/16] KVM: MMU: pass unadulterated gpa to direct_page_fault

Do not bother removing the low bits of the gpa.  This masking dates back
to the very first commit of KVM but it is unnecessary---or even
problematic, because the gpa is later used to fill in the MMIO page cache.

Signed-off-by: Paolo Bonzini <pbonzini@...hat.com>
---
 arch/x86/kvm/mmu/mmu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 964c797dcc46..7477f340d318 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -3950,7 +3950,7 @@ static int nonpaging_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa,
 	pgprintk("%s: gva %lx error %x\n", __func__, gpa, error_code);
 
 	/* This path builds a PAE pagetable, we can map 2mb pages at maximum. */
-	return direct_page_fault(vcpu, gpa & PAGE_MASK, error_code, prefault,
+	return direct_page_fault(vcpu, gpa, error_code, prefault,
 				 PG_LEVEL_2M, false);
 }
 
-- 
2.27.0