From: Sean Christopherson <seanjc@google.com>
To: Paolo Bonzini <pbonzini@redhat.com>
Cc: Sean Christopherson <seanjc@google.com>,
Vitaly Kuznetsov <vkuznets@redhat.com>,
Wanpeng Li <wanpengli@tencent.com>,
Jim Mattson <jmattson@google.com>, Joerg Roedel <joro@8bytes.org>,
kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
syzbot+fb0b6a7e8713aeb0319c@syzkaller.appspotmail.com
Subject: [PATCH 4/9] KVM: x86: Invoke kvm_smm_changed() immediately after clearing SMM flag
Date: Wed, 9 Jun 2021 11:56:14 -0700 [thread overview]
Message-ID: <20210609185619.992058-5-seanjc@google.com> (raw)
In-Reply-To: <20210609185619.992058-1-seanjc@google.com>
Move RSM emulation's call to kvm_smm_changed() from .post_leave_smm() to
.exiting_smm(), leaving behind the MMU context reset. The primary
motivation is to allow for future cleanup, but this also fixes a bug of
sorts by queueing KVM_REQ_EVENT even if RSM causes shutdown, e.g. to let
an INIT wake the vCPU from shutdown. Of course, KVM doesn't properly
emulate a shutdown state, e.g. KVM doesn't block SMIs after shutdown, and
immediately exits to userspace, so the event request is a moot point in
practice.
Moving kvm_smm_changed() also moves the RSM tracepoint. This isn't
strictly necessary, but will allow consolidating the SMI and RSM
tracepoints in a future commit (by also moving the SMI tracepoint).
Invoking the tracepoint before loading SMRAM state also means the SMBASE
that reported in the tracepoint will point that the state that will be
used for RSM, as opposed to the SMBASE _after_ RSM completes, which is
arguably a good thing if the tracepoint is being used to debug a RSM/SMM
issue.
Signed-off-by: Sean Christopherson <seanjc@google.com>
---
arch/x86/kvm/x86.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 69a71c5019c1..76ba28865824 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -7109,7 +7109,7 @@ static void emulator_exiting_smm(struct x86_emulate_ctxt *ctxt)
struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
vcpu->arch.hflags &= ~(HF_SMM_MASK | HF_SMM_INSIDE_NMI_MASK);
- kvm_mmu_reset_context(vcpu);
+ kvm_smm_changed(vcpu);
}
static int emulator_pre_leave_smm(struct x86_emulate_ctxt *ctxt,
@@ -7120,7 +7120,7 @@ static int emulator_pre_leave_smm(struct x86_emulate_ctxt *ctxt,
static void emulator_post_leave_smm(struct x86_emulate_ctxt *ctxt)
{
- kvm_smm_changed(emul_to_vcpu(ctxt));
+ kvm_mmu_reset_context(emul_to_vcpu(ctxt));
}
static void emulator_triple_fault(struct x86_emulate_ctxt *ctxt)
--
2.32.0.rc1.229.g3e70b5a671-goog
next prev parent reply other threads:[~2021-06-09 18:57 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-06-09 18:56 [PATCH 0/9] KVM: x86: Fix NULL pointer #GP due to RSM bug Sean Christopherson
2021-06-09 18:56 ` [PATCH 1/9] KVM: x86: Immediately reset the MMU context when the SMM flag is cleared Sean Christopherson
2021-06-10 13:19 ` Paolo Bonzini
2021-06-09 18:56 ` [PATCH 2/9] KVM: x86: Emulate triple fault shutdown if RSM emulation fails Sean Christopherson
2021-06-10 8:26 ` Vitaly Kuznetsov
2021-06-10 13:29 ` Paolo Bonzini
2021-06-10 15:28 ` Sean Christopherson
2021-06-10 15:30 ` Sean Christopherson
2021-06-11 11:42 ` Vitaly Kuznetsov
2021-06-10 13:23 ` Paolo Bonzini
2021-06-09 18:56 ` [PATCH 3/9] KVM: x86: Replace .set_hflags() with dedicated .exiting_smm() helper Sean Christopherson
2021-06-09 18:56 ` Sean Christopherson [this message]
2021-06-09 18:56 ` [PATCH 5/9] KVM: x86: Move (most) SMM hflags modifications into kvm_smm_changed() Sean Christopherson
2021-06-09 18:56 ` [PATCH 6/9] KVM: x86: Move "entering SMM" tracepoint " Sean Christopherson
2021-06-09 18:56 ` [PATCH 7/9] KVM: x86: Rename SMM tracepoint to make it reflect reality Sean Christopherson
2021-06-09 18:56 ` [PATCH 8/9] KVM: x86: Drop .post_leave_smm(), i.e. the manual post-RSM MMU reset Sean Christopherson
2021-06-09 18:56 ` [PATCH 9/9] KVM: x86: Drop "pre_" from enter/leave_smm() helpers Sean Christopherson
2021-06-10 13:28 ` [PATCH 0/9] KVM: x86: Fix NULL pointer #GP due to RSM bug Paolo Bonzini
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