Disabling HPD polling from i915_hpd_poll_init_work() involves probing
all display connectors explicitly to account for lost hotplug
interrupts. On some platforms (mostly pre-ICL) with HDMI connectors the
I2C EDID bit-banging using udelay() triggers in turn the
workqueue: i915_hpd_poll_init_work [i915] hogged CPU for >10000us 4 times, consider switching to WQ_UNBOUND
warning.
Fix the above by scheduling i915_hpd_poll_init_work() on a WQ_UNBOUND
workqueue. It's ok to use a system WQ, since i915_hpd_poll_init_work()
is properly flushed in intel_hpd_cancel_work().
The connector probing from drm_mode_config::output_poll_work resulting
in the same warning is fixed by the next patch.
Cc: Tejun Heo <tj(a)kernel.org>
Cc: Heiner Kallweit <hkallweit1(a)gmail.com>
CC: stable(a)vger.kernel.org # 6.5
Suggested-by: Tejun Heo <tj(a)kernel.org>
Suggested-by: Heiner Kallweit <hkallweit1(a)gmail.com>
Reported-by: Heiner Kallweit <hkallweit1(a)gmail.com>
Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/9245
Link: https://lore.kernel.org/all/f7e21caa-e98d-e5b5-932a-fe12d27fde9b@gmail.com
Signed-off-by: Imre Deak <imre.deak(a)intel.com>
---
drivers/gpu/drm/i915/display/intel_hotplug.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/i915/display/intel_hotplug.c b/drivers/gpu/drm/i915/display/intel_hotplug.c
index e8562f6f8bb44..accc2fec562a0 100644
--- a/drivers/gpu/drm/i915/display/intel_hotplug.c
+++ b/drivers/gpu/drm/i915/display/intel_hotplug.c
@@ -774,7 +774,7 @@ void intel_hpd_poll_enable(struct drm_i915_private *dev_priv)
* As well, there's no issue if we race here since we always reschedule
* this worker anyway
*/
- queue_work(dev_priv->unordered_wq,
+ queue_work(system_unbound_wq,
&dev_priv->display.hotplug.poll_init_work);
}
@@ -803,7 +803,7 @@ void intel_hpd_poll_disable(struct drm_i915_private *dev_priv)
return;
WRITE_ONCE(dev_priv->display.hotplug.poll_enabled, false);
- queue_work(dev_priv->unordered_wq,
+ queue_work(system_unbound_wq,
&dev_priv->display.hotplug.poll_init_work);
}
--
2.37.2
The patch below does not apply to the 5.15-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y
git checkout FETCH_HEAD
git cherry-pick -x b321c31c9b7b309dcde5e8854b741c8e6a9a05f0
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023072323-trident-unturned-7999@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..
Possible dependencies:
b321c31c9b7b ("KVM: arm64: vgic-v4: Make the doorbell request robust w.r.t preemption")
0c2f9acf6ae7 ("KVM: arm64: PMU: Don't overwrite PMUSERENR with vcpu loaded")
8681f7175901 ("KVM: arm64: PMU: Restore the host's PMUSERENR_EL0")
009d6dc87a56 ("ARM: perf: Allow the use of the PMUv3 driver on 32bit ARM")
711432770f78 ("perf: pmuv3: Abstract PMU version checks")
df29ddf4f04b ("arm64: perf: Abstract system register accesses away")
7755cec63ade ("arm64: perf: Move PMUv3 driver to drivers/perf")
cc91b9481605 ("arm64/perf: Replace PMU version number '0' with ID_AA64DFR0_EL1_PMUVer_NI")
4151bb636acf ("KVM: arm64: Fix SMPRI_EL1/TPIDR2_EL0 trapping on VHE")
bb0cca240a16 ("Merge branch kvm-arm64/single-step-async-exception into kvmarm-master/next")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From b321c31c9b7b309dcde5e8854b741c8e6a9a05f0 Mon Sep 17 00:00:00 2001
From: Marc Zyngier <maz(a)kernel.org>
Date: Thu, 13 Jul 2023 08:06:57 +0100
Subject: [PATCH] KVM: arm64: vgic-v4: Make the doorbell request robust w.r.t
preemption
Xiang reports that VMs occasionally fail to boot on GICv4.1 systems when
running a preemptible kernel, as it is possible that a vCPU is blocked
without requesting a doorbell interrupt.
The issue is that any preemption that occurs between vgic_v4_put() and
schedule() on the block path will mark the vPE as nonresident and *not*
request a doorbell irq. This occurs because when the vcpu thread is
resumed on its way to block, vcpu_load() will make the vPE resident
again. Once the vcpu actually blocks, we don't request a doorbell
anymore, and the vcpu won't be woken up on interrupt delivery.
Fix it by tracking that we're entering WFI, and key the doorbell
request on that flag. This allows us not to make the vPE resident
when going through a preempt/schedule cycle, meaning we don't lose
any state.
Cc: stable(a)vger.kernel.org
Fixes: 8e01d9a396e6 ("KVM: arm64: vgic-v4: Move the GICv4 residency flow to be driven by vcpu_load/put")
Reported-by: Xiang Chen <chenxiang66(a)hisilicon.com>
Suggested-by: Zenghui Yu <yuzenghui(a)huawei.com>
Tested-by: Xiang Chen <chenxiang66(a)hisilicon.com>
Co-developed-by: Oliver Upton <oliver.upton(a)linux.dev>
Signed-off-by: Marc Zyngier <maz(a)kernel.org>
Acked-by: Zenghui Yu <yuzenghui(a)huawei.com>
Link: https://lore.kernel.org/r/20230713070657.3873244-1-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton(a)linux.dev>
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 8b6096753740..d3dd05bbfe23 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -727,6 +727,8 @@ struct kvm_vcpu_arch {
#define DBG_SS_ACTIVE_PENDING __vcpu_single_flag(sflags, BIT(5))
/* PMUSERENR for the guest EL0 is on physical CPU */
#define PMUSERENR_ON_CPU __vcpu_single_flag(sflags, BIT(6))
+/* WFI instruction trapped */
+#define IN_WFI __vcpu_single_flag(sflags, BIT(7))
/* Pointer to the vcpu's SVE FFR for sve_{save,load}_state() */
diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index a402ea5511f3..72dc53a75d1c 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -718,13 +718,15 @@ void kvm_vcpu_wfi(struct kvm_vcpu *vcpu)
*/
preempt_disable();
kvm_vgic_vmcr_sync(vcpu);
- vgic_v4_put(vcpu, true);
+ vcpu_set_flag(vcpu, IN_WFI);
+ vgic_v4_put(vcpu);
preempt_enable();
kvm_vcpu_halt(vcpu);
vcpu_clear_flag(vcpu, IN_WFIT);
preempt_disable();
+ vcpu_clear_flag(vcpu, IN_WFI);
vgic_v4_load(vcpu);
preempt_enable();
}
@@ -792,7 +794,7 @@ static int check_vcpu_requests(struct kvm_vcpu *vcpu)
if (kvm_check_request(KVM_REQ_RELOAD_GICv4, vcpu)) {
/* The distributor enable bits were changed */
preempt_disable();
- vgic_v4_put(vcpu, false);
+ vgic_v4_put(vcpu);
vgic_v4_load(vcpu);
preempt_enable();
}
diff --git a/arch/arm64/kvm/vgic/vgic-v3.c b/arch/arm64/kvm/vgic/vgic-v3.c
index c3b8e132d599..3dfc8b84e03e 100644
--- a/arch/arm64/kvm/vgic/vgic-v3.c
+++ b/arch/arm64/kvm/vgic/vgic-v3.c
@@ -749,7 +749,7 @@ void vgic_v3_put(struct kvm_vcpu *vcpu)
{
struct vgic_v3_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v3;
- WARN_ON(vgic_v4_put(vcpu, false));
+ WARN_ON(vgic_v4_put(vcpu));
vgic_v3_vmcr_sync(vcpu);
diff --git a/arch/arm64/kvm/vgic/vgic-v4.c b/arch/arm64/kvm/vgic/vgic-v4.c
index c1c28fe680ba..339a55194b2c 100644
--- a/arch/arm64/kvm/vgic/vgic-v4.c
+++ b/arch/arm64/kvm/vgic/vgic-v4.c
@@ -336,14 +336,14 @@ void vgic_v4_teardown(struct kvm *kvm)
its_vm->vpes = NULL;
}
-int vgic_v4_put(struct kvm_vcpu *vcpu, bool need_db)
+int vgic_v4_put(struct kvm_vcpu *vcpu)
{
struct its_vpe *vpe = &vcpu->arch.vgic_cpu.vgic_v3.its_vpe;
if (!vgic_supports_direct_msis(vcpu->kvm) || !vpe->resident)
return 0;
- return its_make_vpe_non_resident(vpe, need_db);
+ return its_make_vpe_non_resident(vpe, !!vcpu_get_flag(vcpu, IN_WFI));
}
int vgic_v4_load(struct kvm_vcpu *vcpu)
@@ -354,6 +354,9 @@ int vgic_v4_load(struct kvm_vcpu *vcpu)
if (!vgic_supports_direct_msis(vcpu->kvm) || vpe->resident)
return 0;
+ if (vcpu_get_flag(vcpu, IN_WFI))
+ return 0;
+
/*
* Before making the VPE resident, make sure the redistributor
* corresponding to our current CPU expects us here. See the
diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h
index 402b545959af..5b27f94d4fad 100644
--- a/include/kvm/arm_vgic.h
+++ b/include/kvm/arm_vgic.h
@@ -431,7 +431,7 @@ int kvm_vgic_v4_unset_forwarding(struct kvm *kvm, int irq,
int vgic_v4_load(struct kvm_vcpu *vcpu);
void vgic_v4_commit(struct kvm_vcpu *vcpu);
-int vgic_v4_put(struct kvm_vcpu *vcpu, bool need_db);
+int vgic_v4_put(struct kvm_vcpu *vcpu);
/* CPU HP callbacks */
void kvm_vgic_cpu_up(void);
Recently Luiz Capitulino reported BPF test failure for kernel version
6.1.36 (see [7]). The following test_verifier test failed:
"precise: ST insn causing spi > allocated_stack".
After back-port of the following upstream commit:
ecdf985d7615 ("bpf: track immediate values written to stack by BPF_ST instruction")
Investigation in [8] shows that test failure is not a bug, but a
difference in BPF verifier behavior between upstream, where commits
[1,2,3] by Andrii Nakryiko are present, and 6.1.36, where these
commits are absent. Both Luiz and Greg suggested back-porting [1,2,3]
from upstream to avoid divergences.
Commits [1,2,3] break test_progs selftest "align/packet variable offset",
commit [4] fixes this selftest.
I did some additional testing using the following compiler versions:
- Kernel compilation
- gcc version 11.3.0
- BPF tests compilation
- clang version 16.0.6
- clang version 17.0.0 (fa46feb31481)
And identified a few more failing BPF selftests:
- Tests failing with LLVM 16:
- test_verifier:
- precise: ST insn causing spi > allocated_stack FAIL (fixed by [1,2,3])
- test_progs:
- sk_assign (fixed by [6])
- Tests failing with LLVM 17:
- test_verifier:
- precise: ST insn causing spi > allocated_stack FAIL (fixed by [1,2,3])
- test_progs:
- fexit_bpf2bpf/func_replace_verify (fixed by [5])
- fexit_bpf2bpf/func_replace_return_code (fixed by [5])
- sk_assign (fixed by [6])
Commits [4,5,6] only apply to BPF selftests and don't change verifier
behavior.
After applying all of the listed commits I have test_verifier,
test_progs, test_progs-no_alu32 and test_maps passing on my x86 setup,
both for LLVM 16 and LLVM 17.
Upstream commits in chronological order:
[1] be2ef8161572 ("bpf: allow precision tracking for programs with subprogs")
[2] f63181b6ae79 ("bpf: stop setting precise in current state")
[3] 7a830b53c17b ("bpf: aggressively forget precise markings during state checkpointing")
[4] 4f999b767769 ("selftests/bpf: make test_align selftest more robust")
[5] 63d78b7e8ca2 ("selftests/bpf: Workaround verification failure for fexit_bpf2bpf/func_replace_return_code")
[6] 7ce878ca81bc ("selftests/bpf: Fix sk_assign on s390x")
Links:
[7] https://lore.kernel.org/stable/935c4751-d368-df29-33a6-9f4fcae720fa@amazon.…
[8] https://lore.kernel.org/stable/c9b10a8a551edafdfec855fbd35757c6238ad258.cam…
Changelog:
V1 -> V2: added missing signed-off-by tags
V1: https://lore.kernel.org/stable/20230722004514.767618-1-eddyz87@gmail.com/
Reported-by: Luiz Capitulino <luizcap(a)amazon.com>
Andrii Nakryiko (4):
bpf: allow precision tracking for programs with subprogs
bpf: stop setting precise in current state
bpf: aggressively forget precise markings during state checkpointing
selftests/bpf: make test_align selftest more robust
Ilya Leoshkevich (1):
selftests/bpf: Fix sk_assign on s390x
Yonghong Song (1):
selftests/bpf: Workaround verification failure for
fexit_bpf2bpf/func_replace_return_code
kernel/bpf/verifier.c | 202 ++++++++++++++++--
.../testing/selftests/bpf/prog_tests/align.c | 38 ++--
.../selftests/bpf/prog_tests/sk_assign.c | 25 ++-
.../selftests/bpf/progs/connect4_prog.c | 2 +-
.../selftests/bpf/progs/test_sk_assign.c | 11 +
.../bpf/progs/test_sk_assign_libbpf.c | 3 +
6 files changed, 247 insertions(+), 34 deletions(-)
create mode 100644 tools/testing/selftests/bpf/progs/test_sk_assign_libbpf.c
--
2.41.0
The patch below does not apply to the 5.10-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.10.y
git checkout FETCH_HEAD
git cherry-pick -x b321c31c9b7b309dcde5e8854b741c8e6a9a05f0
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023072324-aviation-delirious-b27d@gregkh' --subject-prefix 'PATCH 5.10.y' HEAD^..
Possible dependencies:
b321c31c9b7b ("KVM: arm64: vgic-v4: Make the doorbell request robust w.r.t preemption")
0c2f9acf6ae7 ("KVM: arm64: PMU: Don't overwrite PMUSERENR with vcpu loaded")
8681f7175901 ("KVM: arm64: PMU: Restore the host's PMUSERENR_EL0")
009d6dc87a56 ("ARM: perf: Allow the use of the PMUv3 driver on 32bit ARM")
711432770f78 ("perf: pmuv3: Abstract PMU version checks")
df29ddf4f04b ("arm64: perf: Abstract system register accesses away")
7755cec63ade ("arm64: perf: Move PMUv3 driver to drivers/perf")
cc91b9481605 ("arm64/perf: Replace PMU version number '0' with ID_AA64DFR0_EL1_PMUVer_NI")
4151bb636acf ("KVM: arm64: Fix SMPRI_EL1/TPIDR2_EL0 trapping on VHE")
bb0cca240a16 ("Merge branch kvm-arm64/single-step-async-exception into kvmarm-master/next")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From b321c31c9b7b309dcde5e8854b741c8e6a9a05f0 Mon Sep 17 00:00:00 2001
From: Marc Zyngier <maz(a)kernel.org>
Date: Thu, 13 Jul 2023 08:06:57 +0100
Subject: [PATCH] KVM: arm64: vgic-v4: Make the doorbell request robust w.r.t
preemption
Xiang reports that VMs occasionally fail to boot on GICv4.1 systems when
running a preemptible kernel, as it is possible that a vCPU is blocked
without requesting a doorbell interrupt.
The issue is that any preemption that occurs between vgic_v4_put() and
schedule() on the block path will mark the vPE as nonresident and *not*
request a doorbell irq. This occurs because when the vcpu thread is
resumed on its way to block, vcpu_load() will make the vPE resident
again. Once the vcpu actually blocks, we don't request a doorbell
anymore, and the vcpu won't be woken up on interrupt delivery.
Fix it by tracking that we're entering WFI, and key the doorbell
request on that flag. This allows us not to make the vPE resident
when going through a preempt/schedule cycle, meaning we don't lose
any state.
Cc: stable(a)vger.kernel.org
Fixes: 8e01d9a396e6 ("KVM: arm64: vgic-v4: Move the GICv4 residency flow to be driven by vcpu_load/put")
Reported-by: Xiang Chen <chenxiang66(a)hisilicon.com>
Suggested-by: Zenghui Yu <yuzenghui(a)huawei.com>
Tested-by: Xiang Chen <chenxiang66(a)hisilicon.com>
Co-developed-by: Oliver Upton <oliver.upton(a)linux.dev>
Signed-off-by: Marc Zyngier <maz(a)kernel.org>
Acked-by: Zenghui Yu <yuzenghui(a)huawei.com>
Link: https://lore.kernel.org/r/20230713070657.3873244-1-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton(a)linux.dev>
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 8b6096753740..d3dd05bbfe23 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -727,6 +727,8 @@ struct kvm_vcpu_arch {
#define DBG_SS_ACTIVE_PENDING __vcpu_single_flag(sflags, BIT(5))
/* PMUSERENR for the guest EL0 is on physical CPU */
#define PMUSERENR_ON_CPU __vcpu_single_flag(sflags, BIT(6))
+/* WFI instruction trapped */
+#define IN_WFI __vcpu_single_flag(sflags, BIT(7))
/* Pointer to the vcpu's SVE FFR for sve_{save,load}_state() */
diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index a402ea5511f3..72dc53a75d1c 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -718,13 +718,15 @@ void kvm_vcpu_wfi(struct kvm_vcpu *vcpu)
*/
preempt_disable();
kvm_vgic_vmcr_sync(vcpu);
- vgic_v4_put(vcpu, true);
+ vcpu_set_flag(vcpu, IN_WFI);
+ vgic_v4_put(vcpu);
preempt_enable();
kvm_vcpu_halt(vcpu);
vcpu_clear_flag(vcpu, IN_WFIT);
preempt_disable();
+ vcpu_clear_flag(vcpu, IN_WFI);
vgic_v4_load(vcpu);
preempt_enable();
}
@@ -792,7 +794,7 @@ static int check_vcpu_requests(struct kvm_vcpu *vcpu)
if (kvm_check_request(KVM_REQ_RELOAD_GICv4, vcpu)) {
/* The distributor enable bits were changed */
preempt_disable();
- vgic_v4_put(vcpu, false);
+ vgic_v4_put(vcpu);
vgic_v4_load(vcpu);
preempt_enable();
}
diff --git a/arch/arm64/kvm/vgic/vgic-v3.c b/arch/arm64/kvm/vgic/vgic-v3.c
index c3b8e132d599..3dfc8b84e03e 100644
--- a/arch/arm64/kvm/vgic/vgic-v3.c
+++ b/arch/arm64/kvm/vgic/vgic-v3.c
@@ -749,7 +749,7 @@ void vgic_v3_put(struct kvm_vcpu *vcpu)
{
struct vgic_v3_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v3;
- WARN_ON(vgic_v4_put(vcpu, false));
+ WARN_ON(vgic_v4_put(vcpu));
vgic_v3_vmcr_sync(vcpu);
diff --git a/arch/arm64/kvm/vgic/vgic-v4.c b/arch/arm64/kvm/vgic/vgic-v4.c
index c1c28fe680ba..339a55194b2c 100644
--- a/arch/arm64/kvm/vgic/vgic-v4.c
+++ b/arch/arm64/kvm/vgic/vgic-v4.c
@@ -336,14 +336,14 @@ void vgic_v4_teardown(struct kvm *kvm)
its_vm->vpes = NULL;
}
-int vgic_v4_put(struct kvm_vcpu *vcpu, bool need_db)
+int vgic_v4_put(struct kvm_vcpu *vcpu)
{
struct its_vpe *vpe = &vcpu->arch.vgic_cpu.vgic_v3.its_vpe;
if (!vgic_supports_direct_msis(vcpu->kvm) || !vpe->resident)
return 0;
- return its_make_vpe_non_resident(vpe, need_db);
+ return its_make_vpe_non_resident(vpe, !!vcpu_get_flag(vcpu, IN_WFI));
}
int vgic_v4_load(struct kvm_vcpu *vcpu)
@@ -354,6 +354,9 @@ int vgic_v4_load(struct kvm_vcpu *vcpu)
if (!vgic_supports_direct_msis(vcpu->kvm) || vpe->resident)
return 0;
+ if (vcpu_get_flag(vcpu, IN_WFI))
+ return 0;
+
/*
* Before making the VPE resident, make sure the redistributor
* corresponding to our current CPU expects us here. See the
diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h
index 402b545959af..5b27f94d4fad 100644
--- a/include/kvm/arm_vgic.h
+++ b/include/kvm/arm_vgic.h
@@ -431,7 +431,7 @@ int kvm_vgic_v4_unset_forwarding(struct kvm *kvm, int irq,
int vgic_v4_load(struct kvm_vcpu *vcpu);
void vgic_v4_commit(struct kvm_vcpu *vcpu);
-int vgic_v4_put(struct kvm_vcpu *vcpu, bool need_db);
+int vgic_v4_put(struct kvm_vcpu *vcpu);
/* CPU HP callbacks */
void kvm_vgic_cpu_up(void);
The patch below does not apply to the 5.10-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.10.y
git checkout FETCH_HEAD
git cherry-pick -x 6c41468c7c12d74843bb414fc00307ea8a6318c3
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023041135-yippee-shabby-b9ad@gregkh' --subject-prefix 'PATCH 5.10.y' HEAD^..
Possible dependencies:
6c41468c7c12 ("KVM: x86: Clear "has_error_code", not "error_code", for RM exception injection")
d4963e319f1f ("KVM: x86: Make kvm_queued_exception a properly named, visible struct")
6ad75c5c99f7 ("KVM: x86: Rename kvm_x86_ops.queue_exception to inject_exception")
5623f751bd9c ("KVM: x86: Treat #DBs from the emulator as fault-like (code and DR7.GD=1)")
8d178f460772 ("KVM: nVMX: Treat General Detect #DB (DR7.GD=1) as fault-like")
eba9799b5a6e ("KVM: VMX: Drop bits 31:16 when shoving exception error code into VMCS")
a61d7c5432ac ("KVM: x86: Trace re-injected exceptions")
6ef88d6e36c2 ("KVM: SVM: Re-inject INT3/INTO instead of retrying the instruction")
3741aec4c38f ("KVM: SVM: Stuff next_rip on emulated INT3 injection if NRIPS is supported")
cd9e6da8048c ("KVM: SVM: Unwind "speculative" RIP advancement if INTn injection "fails"")
00f08d99dd7d ("KVM: nSVM: Sync next_rip field from vmcb12 to vmcb02")
9bd1f0efa859 ("KVM: nVMX: Clear IDT vectoring on nested VM-Exit for double/triple fault")
c3634d25fbee ("KVM: nVMX: Leave most VM-Exit info fields unmodified on failed VM-Entry")
1d5a1b5860ed ("KVM: x86: nSVM: correctly virtualize LBR msrs when L2 is running")
db663af4a001 ("kvm: x86: SVM: use vmcb* instead of svm->vmcb where it makes sense")
b9f3973ab3a8 ("KVM: x86: nSVM: implement nested VMLOAD/VMSAVE")
23e5092b6e2a ("KVM: SVM: Rename hook implementations to conform to kvm_x86_ops' names")
e27bc0440ebd ("KVM: x86: Rename kvm_x86_ops pointers to align w/ preferred vendor names")
068f7ea61895 ("KVM: SVM: improve split between svm_prepare_guest_switch and sev_es_prepare_guest_switch")
e1779c2714c3 ("KVM: x86: nSVM: fix potential NULL derefernce on nested migration")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 6c41468c7c12d74843bb414fc00307ea8a6318c3 Mon Sep 17 00:00:00 2001
From: Sean Christopherson <seanjc(a)google.com>
Date: Wed, 22 Mar 2023 07:32:59 -0700
Subject: [PATCH] KVM: x86: Clear "has_error_code", not "error_code", for RM
exception injection
When injecting an exception into a vCPU in Real Mode, suppress the error
code by clearing the flag that tracks whether the error code is valid, not
by clearing the error code itself. The "typo" was introduced by recent
fix for SVM's funky Paged Real Mode.
Opportunistically hoist the logic above the tracepoint so that the trace
is coherent with respect to what is actually injected (this was also the
behavior prior to the buggy commit).
Fixes: b97f07458373 ("KVM: x86: determine if an exception has an error code only when injecting it.")
Cc: stable(a)vger.kernel.org
Cc: Maxim Levitsky <mlevitsk(a)redhat.com>
Signed-off-by: Sean Christopherson <seanjc(a)google.com>
Message-Id: <20230322143300.2209476-2-seanjc(a)google.com>
Signed-off-by: Paolo Bonzini <pbonzini(a)redhat.com>
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 45017576ad5e..7d6f98b7635f 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -9908,13 +9908,20 @@ int kvm_check_nested_events(struct kvm_vcpu *vcpu)
static void kvm_inject_exception(struct kvm_vcpu *vcpu)
{
+ /*
+ * Suppress the error code if the vCPU is in Real Mode, as Real Mode
+ * exceptions don't report error codes. The presence of an error code
+ * is carried with the exception and only stripped when the exception
+ * is injected as intercepted #PF VM-Exits for AMD's Paged Real Mode do
+ * report an error code despite the CPU being in Real Mode.
+ */
+ vcpu->arch.exception.has_error_code &= is_protmode(vcpu);
+
trace_kvm_inj_exception(vcpu->arch.exception.vector,
vcpu->arch.exception.has_error_code,
vcpu->arch.exception.error_code,
vcpu->arch.exception.injected);
- if (vcpu->arch.exception.error_code && !is_protmode(vcpu))
- vcpu->arch.exception.error_code = false;
static_call(kvm_x86_inject_exception)(vcpu);
}