From: Sean Christopherson <seanjc@google.com>
To: Sean Christopherson <seanjc@google.com>,
Paolo Bonzini <pbonzini@redhat.com>
Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
Alejandro Jimenez <alejandro.j.jimenez@oracle.com>,
Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>,
Maxim Levitsky <mlevitsk@redhat.com>,
Li RongQing <lirongqing@baidu.com>
Subject: [PATCH v3 24/28] KVM: SVM: Update svm->ldr_reg cache even if LDR is "bad"
Date: Tue, 20 Sep 2022 23:31:30 +0000 [thread overview]
Message-ID: <20220920233134.940511-25-seanjc@google.com> (raw)
In-Reply-To: <20220920233134.940511-1-seanjc@google.com>
Update SVM's cache of the LDR even if the new value is "bad". Leaving
stale information in the cache can result in KVM missing updates and/or
invalidating the wrong entry, e.g. if avic_invalidate_logical_id_entry()
is triggered after a different vCPU has "claimed" the old LDR.
Fixes: 18f40c53e10f ("svm: Add VMEXIT handlers for AVIC")
Signed-off-by: Sean Christopherson <seanjc@google.com>
---
arch/x86/kvm/svm/avic.c | 17 +++++++----------
1 file changed, 7 insertions(+), 10 deletions(-)
diff --git a/arch/x86/kvm/svm/avic.c b/arch/x86/kvm/svm/avic.c
index 2b640c73f447..4b6fc9d64f4d 100644
--- a/arch/x86/kvm/svm/avic.c
+++ b/arch/x86/kvm/svm/avic.c
@@ -539,23 +539,24 @@ static u32 *avic_get_logical_id_entry(struct kvm_vcpu *vcpu, u32 ldr, bool flat)
return &logical_apic_id_table[index];
}
-static int avic_ldr_write(struct kvm_vcpu *vcpu, u8 g_physical_id, u32 ldr)
+static void avic_ldr_write(struct kvm_vcpu *vcpu, u8 g_physical_id, u32 ldr)
{
bool flat;
u32 *entry, new_entry;
+ if (!ldr)
+ return;
+
flat = kvm_lapic_get_reg(vcpu->arch.apic, APIC_DFR) == APIC_DFR_FLAT;
entry = avic_get_logical_id_entry(vcpu, ldr, flat);
if (!entry)
- return -EINVAL;
+ return;
new_entry = READ_ONCE(*entry);
new_entry &= ~AVIC_LOGICAL_ID_ENTRY_GUEST_PHYSICAL_ID_MASK;
new_entry |= (g_physical_id & AVIC_LOGICAL_ID_ENTRY_GUEST_PHYSICAL_ID_MASK);
new_entry |= AVIC_LOGICAL_ID_ENTRY_VALID_MASK;
WRITE_ONCE(*entry, new_entry);
-
- return 0;
}
static void avic_invalidate_logical_id_entry(struct kvm_vcpu *vcpu)
@@ -575,7 +576,6 @@ static void avic_invalidate_logical_id_entry(struct kvm_vcpu *vcpu)
static void avic_handle_ldr_update(struct kvm_vcpu *vcpu)
{
- int ret = 0;
struct vcpu_svm *svm = to_svm(vcpu);
u32 ldr = kvm_lapic_get_reg(vcpu->arch.apic, APIC_LDR);
u32 id = kvm_xapic_id(vcpu->arch.apic);
@@ -589,11 +589,8 @@ static void avic_handle_ldr_update(struct kvm_vcpu *vcpu)
avic_invalidate_logical_id_entry(vcpu);
- if (ldr)
- ret = avic_ldr_write(vcpu, id, ldr);
-
- if (!ret)
- svm->ldr_reg = ldr;
+ svm->ldr_reg = ldr;
+ avic_ldr_write(vcpu, id, ldr);
}
static void avic_handle_dfr_update(struct kvm_vcpu *vcpu)
--
2.37.3.968.ga6b4b080e4-goog
next prev parent reply other threads:[~2022-09-20 23:34 UTC|newest]
Thread overview: 43+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-09-20 23:31 [PATCH v3 00/28] KVM: x86: AVIC and local APIC fixes+cleanups Sean Christopherson
2022-09-20 23:31 ` [PATCH v3 01/28] KVM: x86: Blindly get current x2APIC reg value on "nodecode write" traps Sean Christopherson
2022-09-20 23:31 ` [PATCH v3 02/28] KVM: x86: Purge "highest ISR" cache when updating APICv state Sean Christopherson
2022-09-20 23:31 ` [PATCH v3 03/28] KVM: SVM: Flush the "current" TLB when activating AVIC Sean Christopherson
2022-09-20 23:31 ` [PATCH v3 04/28] KVM: SVM: Process ICR on AVIC IPI delivery failure due to invalid target Sean Christopherson
2022-09-20 23:31 ` [PATCH v3 05/28] KVM: x86: Don't inhibit APICv/AVIC if xAPIC ID mismatch is due to 32-bit ID Sean Christopherson
2022-09-28 3:15 ` Alejandro Jimenez
2022-09-28 5:55 ` Maxim Levitsky
2022-09-28 16:51 ` Sean Christopherson
2022-09-28 17:51 ` Maxim Levitsky
2022-09-28 18:03 ` Sean Christopherson
2022-09-28 18:16 ` Maxim Levitsky
2022-09-28 20:44 ` Sean Christopherson
2022-09-28 20:50 ` Alejandro Jimenez
2022-09-20 23:31 ` [PATCH v3 06/28] KVM: x86: Move APIC access page helper to common x86 code Sean Christopherson
2022-09-20 23:31 ` [PATCH v3 07/28] KVM: x86: Inhibit APIC memslot if x2APIC and AVIC are enabled Sean Christopherson
2022-09-23 10:27 ` Maxim Levitsky
2022-09-26 17:00 ` Sean Christopherson
2022-09-28 6:21 ` Maxim Levitsky
2022-09-28 16:33 ` Sean Christopherson
2022-09-28 17:40 ` Maxim Levitsky
2022-09-28 22:35 ` Sean Christopherson
2022-09-20 23:31 ` [PATCH v3 08/28] KVM: SVM: Don't put/load AVIC when setting virtual APIC mode Sean Christopherson
2022-09-20 23:31 ` [PATCH v3 09/28] KVM: SVM: Replace "avic_mode" enum with "x2avic_enabled" boolean Sean Christopherson
2022-09-20 23:31 ` [PATCH v3 10/28] KVM: SVM: Compute dest based on sender's x2APIC status for AVIC kick Sean Christopherson
2022-09-20 23:31 ` [PATCH v3 11/28] KVM: SVM: Fix x2APIC Logical ID calculation for avic_kick_target_vcpus_fast Sean Christopherson
2022-09-20 23:31 ` [PATCH v3 12/28] Revert "KVM: SVM: Use target APIC ID to complete x2AVIC IRQs when possible" Sean Christopherson
2022-09-20 23:31 ` [PATCH v3 13/28] KVM: SVM: Document that vCPU ID == APIC ID in AVIC kick fastpatch Sean Christopherson
2022-09-20 23:31 ` [PATCH v3 14/28] KVM: SVM: Add helper to perform final AVIC "kick" of single vCPU Sean Christopherson
2022-09-20 23:31 ` [PATCH v3 15/28] KVM: x86: Explicitly skip optimized logical map setup if vCPU's LDR==0 Sean Christopherson
2022-09-20 23:31 ` [PATCH v3 16/28] KVM: x86: Explicitly track all possibilities for APIC map's logical modes Sean Christopherson
2022-09-20 23:31 ` [PATCH v3 17/28] KVM: x86: Skip redundant x2APIC logical mode optimized cluster setup Sean Christopherson
2022-09-20 23:31 ` [PATCH v3 18/28] KVM: x86: Disable APIC logical map if logical ID covers multiple MDAs Sean Christopherson
2022-09-20 23:31 ` [PATCH v3 19/28] KVM: x86: Disable APIC logical map if vCPUs are aliased in logical mode Sean Christopherson
2022-09-20 23:31 ` [PATCH v3 20/28] KVM: x86: Honor architectural behavior for aliased 8-bit APIC IDs Sean Christopherson
2022-09-20 23:31 ` [PATCH v3 21/28] KVM: x86: Inhibit APICv/AVIC if the optimized physical map is disabled Sean Christopherson
2022-09-20 23:31 ` [PATCH v3 22/28] KVM: SVM: Inhibit AVIC if vCPUs are aliased in logical mode Sean Christopherson
2022-09-20 23:31 ` [PATCH v3 23/28] KVM: SVM: Always update local APIC on writes to logical dest register Sean Christopherson
2022-09-20 23:31 ` Sean Christopherson [this message]
2022-09-20 23:31 ` [PATCH v3 25/28] KVM: SVM: Require logical ID to be power-of-2 for AVIC entry Sean Christopherson
2022-09-20 23:31 ` [PATCH v3 26/28] KVM: SVM: Handle multiple logical targets in AVIC kick fastpath Sean Christopherson
2022-09-20 23:31 ` [PATCH v3 27/28] KVM: SVM: Ignore writes to Remote Read Data on AVIC write traps Sean Christopherson
2022-09-20 23:31 ` [PATCH v3 28/28] Revert "KVM: SVM: Do not throw warning when calling avic_vcpu_load on a running vcpu" Sean Christopherson
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20220920233134.940511-25-seanjc@google.com \
--to=seanjc@google.com \
--cc=alejandro.j.jimenez@oracle.com \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=lirongqing@baidu.com \
--cc=mlevitsk@redhat.com \
--cc=pbonzini@redhat.com \
--cc=suravee.suthikulpanit@amd.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
all inboxes | Powered by JetHome®