Re: [PATCH 03/15] KVM: x86: avoid unnecessarily guest page tablewalking
From: Avi Kivity
Date: Thu Jun 09 2011 - 02:59:55 EST
On 06/07/2011 03:59 PM, Xiao Guangrong wrote:
We already get the guest physical address, so use it to read guest data
directly to avoid walking guest page table again
Signed-off-by: Xiao Guangrong<xiaoguangrong@xxxxxxxxxxxxxx>
---
arch/x86/kvm/x86.c | 3 +--
1 files changed, 1 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 694538a..8be9ff6 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3930,8 +3930,7 @@ static int emulator_read_emulated(struct x86_emulate_ctxt *ctxt,
if ((gpa& PAGE_MASK) == APIC_DEFAULT_PHYS_BASE)
goto mmio;
- if (kvm_read_guest_virt(ctxt, addr, val, bytes, exception)
- == X86EMUL_CONTINUE)
+ if (!kvm_read_guest(vcpu->kvm, gpa, val, bytes))
return X86EMUL_CONTINUE;
This breaks is addr/bytes spans a page boundary.
(the current code is also broken, but only for mmio; the new code is
broken for ram as well).
We need a gva_to_gpa() that returns a range of pages.
--
error compiling committee.c: too many arguments to function
--
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