KVM: x86/ioapic: Resample the pending state of an IRQ when unmasking

KVM irqfd based emulation of level-triggered interrupts doesn't work
quite correctly in some cases, particularly in the case of i

KVM: x86/ioapic: Resample the pending state of an IRQ when unmasking

KVM irqfd based emulation of level-triggered interrupts doesn't work
quite correctly in some cases, particularly in the case of interrupts
that are handled in a Linux guest as oneshot interrupts (IRQF_ONESHOT).
Such an interrupt is acked to the device in its threaded irq handler,
i.e. later than it is acked to the interrupt controller (EOI at the end
of hardirq), not earlier.

Linux keeps such interrupt masked until its threaded handler finishes,
to prevent the EOI from re-asserting an unacknowledged interrupt.
However, with KVM + vfio (or whatever is listening on the resamplefd)
we always notify resamplefd at the EOI, so vfio prematurely unmasks the
host physical IRQ, thus a new physical interrupt is fired in the host.
This extra interrupt in the host is not a problem per se. The problem is
that it is unconditionally queued for injection into the guest, so the
guest sees an extra bogus interrupt. [*]

There are observed at least 2 user-visible issues caused by those
extra erroneous interrupts for a oneshot irq in the guest:

1. System suspend aborted due to a pending wakeup interrupt from
ChromeOS EC (drivers/platform/chrome/cros_ec.c).
2. Annoying "invalid report id data" errors from ELAN0000 touchpad
(drivers/input/mouse/elan_i2c_core.c), flooding the guest dmesg
every time the touchpad is touched.

The core issue here is that by the time when the guest unmasks the IRQ,
the physical IRQ line is no longer asserted (since the guest has
acked the interrupt to the device in the meantime), yet we
unconditionally inject the interrupt queued into the guest by the
previous resampling. So to fix the issue, we need a way to detect that
the IRQ is no longer pending, and cancel the queued interrupt in this
case.

With IOAPIC we are not able to probe the physical IRQ line state
directly (at least not if the underlying physical interrupt controller
is an IOAPIC too), so in this patch we use irqfd resampler for that.
Namely, instead of injecting the queued interrupt, we just notify the
resampler that this interrupt is done. If the IRQ line is actually
already deasserted, we are done. If it is still asserted, a new
interrupt will be shortly triggered through irqfd and injected into the
guest.

In the case if there is no irqfd resampler registered for this IRQ, we
cannot fix the issue, so we keep the existing behavior: immediately
unconditionally inject the queued interrupt.

This patch fixes the issue for x86 IOAPIC only. In the long run, we can
fix it for other irqchips and other architectures too, possibly taking
advantage of reading the physical state of the IRQ line, which is
possible with some other irqchips (e.g. with arm64 GIC, maybe even with
the legacy x86 PIC).

[*] In this description we assume that the interrupt is a physical host
interrupt forwarded to the guest e.g. by vfio. Potentially the same
issue may occur also with a purely virtual interrupt from an
emulated device, e.g. if the guest handles this interrupt, again, as
a oneshot interrupt.

Signed-off-by: Dmytro Maluka <dmy@semihalf.com>
Link: https://lore.kernel.org/kvm/31420943-8c5f-125c-a5ee-d2fde2700083@semihalf.com/
Link: https://lore.kernel.org/lkml/87o7wrug0w.wl-maz@kernel.org/
Message-Id: <20230322204344.50138-3-dmy@semihalf.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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KVM: x86: Unify pr_fmt to use module name for all KVM modules

Define pr_fmt using KBUILD_MODNAME for all KVM x86 code so that printks
use consistent formatting across common x86, Intel, and AMD code

KVM: x86: Unify pr_fmt to use module name for all KVM modules

Define pr_fmt using KBUILD_MODNAME for all KVM x86 code so that printks
use consistent formatting across common x86, Intel, and AMD code. In
addition to providing consistent print formatting, using KBUILD_MODNAME,
e.g. kvm_amd and kvm_intel, allows referencing SVM and VMX (and SEV and
SGX and ...) as technologies without generating weird messages, and
without causing naming conflicts with other kernel code, e.g. "SEV: ",
"tdx: ", "sgx: " etc.. are all used by the kernel for non-KVM subsystems.

Opportunistically move away from printk() for prints that need to be
modified anyways, e.g. to drop a manual "kvm: " prefix.

Opportunistically convert a few SGX WARNs that are similarly modified to
WARN_ONCE; in the very unlikely event that the WARNs fire, odds are good
that they would fire repeatedly and spam the kernel log without providing
unique information in each print.

Note, defining pr_fmt yields undesirable results for code that uses KVM's
printk wrappers, e.g. vcpu_unimpl(). But, that's a pre-existing problem
as SVM/kvm_amd already defines a pr_fmt, and thankfully use of KVM's
wrappers is relatively limited in KVM x86 code.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Message-Id: <20221130230934.1014142-35-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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KVM: x86/ioapic: Remove unused "addr" and "length" of ioapic_read_indirect()

The "unsigned long addr" and "unsigned long length" parameter of
ioapic_read_indirect() is not used, so remove it.

No fu

KVM: x86/ioapic: Remove unused "addr" and "length" of ioapic_read_indirect()

The "unsigned long addr" and "unsigned long length" parameter of
ioapic_read_indirect() is not used, so remove it.

No functional change intended.

Signed-off-by: Jinrong Liang <cloudliang@tencent.com>
Message-Id: <20220125095909.38122-14-cloudliang@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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KVM: Use 'unsigned long' as kvm_for_each_vcpu()'s index

Everywhere we use kvm_for_each_vpcu(), we use an int as the vcpu
index. Unfortunately, we're about to move rework the iterator,
which requires

KVM: Use 'unsigned long' as kvm_for_each_vcpu()'s index

Everywhere we use kvm_for_each_vpcu(), we use an int as the vcpu
index. Unfortunately, we're about to move rework the iterator,
which requires this to be upgrade to an unsigned long.

Let's bite the bullet and repaint all of it in one go.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Message-Id: <20211116160403.4074052-7-maz@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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kvm: rename KVM_MAX_VCPU_ID to KVM_MAX_VCPU_IDS

KVM_MAX_VCPU_ID is not specifying the highest allowed vcpu-id, but the
number of allowed vcpu-ids. This has already led to confusion, so
rename KVM_MA

kvm: rename KVM_MAX_VCPU_ID to KVM_MAX_VCPU_IDS

KVM_MAX_VCPU_ID is not specifying the highest allowed vcpu-id, but the
number of allowed vcpu-ids. This has already led to confusion, so
rename KVM_MAX_VCPU_ID to KVM_MAX_VCPU_IDS to make its semantics more
clear

Suggested-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210913135745.13944-3-jgross@suse.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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Revert "x86/kvm: fix vcpu-id indexed array sizes"

This reverts commit 76b4f357d0e7d8f6f0013c733e6cba1773c266d3.

The commit has the wrong reasoning, as KVM_MAX_VCPU_ID is not defining the
maximum al

Revert "x86/kvm: fix vcpu-id indexed array sizes"

This reverts commit 76b4f357d0e7d8f6f0013c733e6cba1773c266d3.

The commit has the wrong reasoning, as KVM_MAX_VCPU_ID is not defining the
maximum allowed vcpu-id as its name suggests, but the number of vcpu-ids.
So revert this patch again.

Suggested-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210913135745.13944-2-jgross@suse.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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Revert "x86/kvm: fix vcpu-id indexed array sizes"

commit 1e254d0d86a0f2efd4190a89d5204b37c18c6381 upstream.

This reverts commit 76b4f357d0e7d8f6f0013c733e6cba1773c266d3.

The commit has the wrong r

Revert "x86/kvm: fix vcpu-id indexed array sizes"

commit 1e254d0d86a0f2efd4190a89d5204b37c18c6381 upstream.

This reverts commit 76b4f357d0e7d8f6f0013c733e6cba1773c266d3.

The commit has the wrong reasoning, as KVM_MAX_VCPU_ID is not defining the
maximum allowed vcpu-id as its name suggests, but the number of vcpu-ids.
So revert this patch again.

Suggested-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210913135745.13944-2-jgross@suse.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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KVM: x86: Fix stack-out-of-bounds memory access from ioapic_write_indirect()

KASAN reports the following issue:

BUG: KASAN: stack-out-of-bounds in kvm_make_vcpus_request_mask+0x174/0x440 [kvm]
Re

KVM: x86: Fix stack-out-of-bounds memory access from ioapic_write_indirect()

KASAN reports the following issue:

BUG: KASAN: stack-out-of-bounds in kvm_make_vcpus_request_mask+0x174/0x440 [kvm]
Read of size 8 at addr ffffc9001364f638 by task qemu-kvm/4798

CPU: 0 PID: 4798 Comm: qemu-kvm Tainted: G X --------- ---
Hardware name: AMD Corporation DAYTONA_X/DAYTONA_X, BIOS RYM0081C 07/13/2020
Call Trace:
dump_stack+0xa5/0xe6
print_address_description.constprop.0+0x18/0x130
? kvm_make_vcpus_request_mask+0x174/0x440 [kvm]
__kasan_report.cold+0x7f/0x114
? kvm_make_vcpus_request_mask+0x174/0x440 [kvm]
kasan_report+0x38/0x50
kasan_check_range+0xf5/0x1d0
kvm_make_vcpus_request_mask+0x174/0x440 [kvm]
kvm_make_scan_ioapic_request_mask+0x84/0xc0 [kvm]
? kvm_arch_exit+0x110/0x110 [kvm]
? sched_clock+0x5/0x10
ioapic_write_indirect+0x59f/0x9e0 [kvm]
? static_obj+0xc0/0xc0
? __lock_acquired+0x1d2/0x8c0
? kvm_ioapic_eoi_inject_work+0x120/0x120 [kvm]

The problem appears to be that 'vcpu_bitmap' is allocated as a single long
on stack and it should really be KVM_MAX_VCPUS long. We also seem to clear
the lower 16 bits of it with bitmap_zero() for no particular reason (my
guess would be that 'bitmap' and 'vcpu_bitmap' variables in
kvm_bitmap_or_dest_vcpus() caused the confusion: while the later is indeed
16-bit long, the later should accommodate all possible vCPUs).

Fixes: 7ee30bc132c6 ("KVM: x86: deliver KVM IOAPIC scan request to target vCPUs")
Fixes: 9a2ae9f6b6bb ("KVM: x86: Zero the IOAPIC scan request dest vCPUs bitmap")
Reported-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210827092516.1027264-7-vkuznets@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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x86/kvm: fix vcpu-id indexed array sizes

KVM_MAX_VCPU_ID is the maximum vcpu-id of a guest, and not the number
of vcpu-ids. Fix array indexed by vcpu-id to have KVM_MAX_VCPU_ID+1
elements.

Note tha

x86/kvm: fix vcpu-id indexed array sizes

KVM_MAX_VCPU_ID is the maximum vcpu-id of a guest, and not the number
of vcpu-ids. Fix array indexed by vcpu-id to have KVM_MAX_VCPU_ID+1
elements.

Note that this is currently no real problem, as KVM_MAX_VCPU_ID is
an odd number, resulting in always enough padding being available at
the end of those arrays.

Nevertheless this should be fixed in order to avoid rare problems in
case someone is using an even number for KVM_MAX_VCPU_ID.

Signed-off-by: Juergen Gross <jgross@suse.com>
Message-Id: <20210701154105.23215-2-jgross@suse.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

show more ...

x86/kvm: fix vcpu-id indexed array sizes

commit 76b4f357d0e7d8f6f0013c733e6cba1773c266d3 upstream.

KVM_MAX_VCPU_ID is the maximum vcpu-id of a guest, and not the number
of vcpu-ids. Fix array index

x86/kvm: fix vcpu-id indexed array sizes

commit 76b4f357d0e7d8f6f0013c733e6cba1773c266d3 upstream.

KVM_MAX_VCPU_ID is the maximum vcpu-id of a guest, and not the number
of vcpu-ids. Fix array indexed by vcpu-id to have KVM_MAX_VCPU_ID+1
elements.

Note that this is currently no real problem, as KVM_MAX_VCPU_ID is
an odd number, resulting in always enough padding being available at
the end of those arrays.

Nevertheless this should be fixed in order to avoid rare problems in
case someone is using an even number for KVM_MAX_VCPU_ID.

Signed-off-by: Juergen Gross <jgross@suse.com>
Message-Id: <20210701154105.23215-2-jgross@suse.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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KVM: ioapic: break infinite recursion on lazy EOI

During shutdown the IOAPIC trigger mode is reset to edge triggered
while the vfio-pci INTx is still registered with a resampler.
This allows us to g

KVM: ioapic: break infinite recursion on lazy EOI

During shutdown the IOAPIC trigger mode is reset to edge triggered
while the vfio-pci INTx is still registered with a resampler.
This allows us to get into an infinite loop:

ioapic_set_irq
-> ioapic_lazy_update_eoi
-> kvm_ioapic_update_eoi_one
-> kvm_notify_acked_irq
-> kvm_notify_acked_gsi
-> (via irq_acked fn ptr) irqfd_resampler_ack
-> kvm_set_irq
-> (via set fn ptr) kvm_set_ioapic_irq
-> kvm_ioapic_set_irq
-> ioapic_set_irq

Commit 8be8f932e3db ("kvm: ioapic: Restrict lazy EOI update to
edge-triggered interrupts", 2020-05-04) acknowledges that this recursion
loop exists and tries to avoid it at the call to ioapic_lazy_update_eoi,
but at this point the scenario is already set, we have an edge interrupt
with resampler on the same gsi.

Fortunately, the only user of irq ack notifiers (in addition to resamplefd)
is i8254 timer interrupt reinjection. These are edge-triggered, so in
principle they would need the call to kvm_ioapic_update_eoi_one from
ioapic_lazy_update_eoi, but they already disable AVIC(*), so they don't
need the lazy EOI behavior. Therefore, remove the call to
kvm_ioapic_update_eoi_one from ioapic_lazy_update_eoi.

This fixes CVE-2020-27152. Note that this issue cannot happen with
SR-IOV assigned devices because virtual functions do not have INTx,
only MSI.

Fixes: f458d039db7e ("kvm: ioapic: Lazy update IOAPIC EOI")
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Tested-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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kvm: ioapic: Restrict lazy EOI update to edge-triggered interrupts

Commit f458d039db7e ("kvm: ioapic: Lazy update IOAPIC EOI") introduces
the following infinite loop:

BUG: stack guard page was hit

kvm: ioapic: Restrict lazy EOI update to edge-triggered interrupts

Commit f458d039db7e ("kvm: ioapic: Lazy update IOAPIC EOI") introduces
the following infinite loop:

BUG: stack guard page was hit at 000000008f595917 \
(stack is 00000000bdefe5a4..00000000ae2b06f5)
kernel stack overflow (double-fault): 0000 [#1] SMP NOPTI
RIP: 0010:kvm_set_irq+0x51/0x160 [kvm]
Call Trace:
irqfd_resampler_ack+0x32/0x90 [kvm]
kvm_notify_acked_irq+0x62/0xd0 [kvm]
kvm_ioapic_update_eoi_one.isra.0+0x30/0x120 [kvm]
ioapic_set_irq+0x20e/0x240 [kvm]
kvm_ioapic_set_irq+0x5c/0x80 [kvm]
kvm_set_irq+0xbb/0x160 [kvm]
? kvm_hv_set_sint+0x20/0x20 [kvm]
irqfd_resampler_ack+0x32/0x90 [kvm]
kvm_notify_acked_irq+0x62/0xd0 [kvm]
kvm_ioapic_update_eoi_one.isra.0+0x30/0x120 [kvm]
ioapic_set_irq+0x20e/0x240 [kvm]
kvm_ioapic_set_irq+0x5c/0x80 [kvm]
kvm_set_irq+0xbb/0x160 [kvm]
? kvm_hv_set_sint+0x20/0x20 [kvm]
....

The re-entrancy happens because the irq state is the OR of
the interrupt state and the resamplefd state. That is, we don't
want to show the state as 0 until we've had a chance to set the
resamplefd. But if the interrupt has _not_ gone low then
ioapic_set_irq is invoked again, causing an infinite loop.

This can only happen for a level-triggered interrupt, otherwise
irqfd_inject would immediately set the KVM_USERSPACE_IRQ_SOURCE_ID high
and then low. Fortunately, in the case of level-triggered interrupts the VMEXIT already happens because
TMR is set. Thus, fix the bug by restricting the lazy invocation
of the ack notifier to edge-triggered interrupts, the only ones that
need it.

Tested-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Reported-by: borisvk@bstnet.org
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Link: https://www.spinics.net/lists/kvm/msg213512.html
Fixes: f458d039db7e ("kvm: ioapic: Lazy update IOAPIC EOI")
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=207489
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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KVM: x86: Initializing all kvm_lapic_irq fields in ioapic_write_indirect

Previously all fields of structure kvm_lapic_irq were not initialized
before it was passed to kvm_bitmap_or_dest_vcpus(). Whi

KVM: x86: Initializing all kvm_lapic_irq fields in ioapic_write_indirect

Previously all fields of structure kvm_lapic_irq were not initialized
before it was passed to kvm_bitmap_or_dest_vcpus(). Which will cause
an issue when any of those fields are used for processing a request.
For example not initializing the msi_redir_hint field before passing
to the kvm_bitmap_or_dest_vcpus(), may lead to a misbehavior of
kvm_apic_map_get_dest_lapic(). This will specifically happen when the
kvm_lowest_prio_delivery() returns TRUE due to a non-zero garbage
value of msi_redir_hint, which should not happen as the request belongs
to APIC fixed delivery mode and we do not want to deliver the
interrupt only to the lowest priority candidate.

This patch initializes all the fields of kvm_lapic_irq based on the
values of ioapic redirect_entry object before passing it on to
kvm_bitmap_or_dest_vcpus().

Fixes: 7ee30bc132c6 ("KVM: x86: deliver KVM IOAPIC scan request to target vCPUs")
Signed-off-by: Nitesh Narayan Lal <nitesh@redhat.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
[Set level to false since the value doesn't really matter. Suggested
by Vitaly Kuznetsov. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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kvm: ioapic: Lazy update IOAPIC EOI

In-kernel IOAPIC does not receive EOI with AMD SVM AVIC
since the processor accelerate write to APIC EOI register and
does not trap if the interrupt is edge-trigg

kvm: ioapic: Lazy update IOAPIC EOI

In-kernel IOAPIC does not receive EOI with AMD SVM AVIC
since the processor accelerate write to APIC EOI register and
does not trap if the interrupt is edge-triggered.

Workaround this by lazy check for pending APIC EOI at the time when
setting new IOPIC irq, and update IOAPIC EOI if no pending APIC EOI.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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kvm: ioapic: Refactor kvm_ioapic_update_eoi()

Refactor code for handling IOAPIC EOI for subsequent patch.
There is no functional change.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@

kvm: ioapic: Refactor kvm_ioapic_update_eoi()

Refactor code for handling IOAPIC EOI for subsequent patch.
There is no functional change.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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KVM: x86: Protect ioapic_write_indirect() from Spectre-v1/L1TF attacks

This fixes a Spectre-v1/L1TF vulnerability in ioapic_write_indirect().
This function contains index computations based on the
(

KVM: x86: Protect ioapic_write_indirect() from Spectre-v1/L1TF attacks

This fixes a Spectre-v1/L1TF vulnerability in ioapic_write_indirect().
This function contains index computations based on the
(attacker-controlled) IOREGSEL register.

This patch depends on patch
"KVM: x86: Protect ioapic_read_indirect() from Spectre-v1/L1TF attacks".

Fixes: 70f93dae32ac ("KVM: Use temporary variable to shorten lines.")

Signed-off-by: Nick Finco <nifi@google.com>
Signed-off-by: Marios Pomonis <pomonis@google.com>
Reviewed-by: Andrew Honig <ahonig@google.com>
Cc: stable@vger.kernel.org
Reviewed-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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KVM: x86: Protect ioapic_read_indirect() from Spectre-v1/L1TF attacks

This fixes a Spectre-v1/L1TF vulnerability in ioapic_read_indirect().
This function contains index computations based on the
(at

KVM: x86: Protect ioapic_read_indirect() from Spectre-v1/L1TF attacks

This fixes a Spectre-v1/L1TF vulnerability in ioapic_read_indirect().
This function contains index computations based on the
(attacker-controlled) IOREGSEL register.

Fixes: a2c118bfab8b ("KVM: Fix bounds checking in ioapic indirect register reads (CVE-2013-1798)")

Signed-off-by: Nick Finco <nifi@google.com>
Signed-off-by: Marios Pomonis <pomonis@google.com>
Reviewed-by: Andrew Honig <ahonig@google.com>
Cc: stable@vger.kernel.org
Reviewed-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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KVM: Fix some grammar mistakes

Fix some grammar mistakes in the comments.

Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: X86: Convert the last users of "shorthand = 0" to use macros

Change the last users of "shorthand = 0" to use APIC_DEST_NOSHORT.

Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-b

KVM: X86: Convert the last users of "shorthand = 0" to use macros

Change the last users of "shorthand = 0" to use APIC_DEST_NOSHORT.

Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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KVM: X86: Fix callers of kvm_apic_match_dest() to use correct macros

Callers of kvm_apic_match_dest() should always pass in APIC_DEST_*
macros for either dest_mode and short_hand parameters. Fix up

KVM: X86: Fix callers of kvm_apic_match_dest() to use correct macros

Callers of kvm_apic_match_dest() should always pass in APIC_DEST_*
macros for either dest_mode and short_hand parameters. Fix up all the
callers of kvm_apic_match_dest() that are not following the rule.

Since at it, rename the parameter from short_hand to shorthand in
kvm_apic_match_dest(), as suggested by Vitaly.

Reported-by: Sean Christopherson <sean.j.christopherson@intel.com>
Reported-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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KVM: X86: Use APIC_DEST_* macros properly in kvm_lapic_irq.dest_mode

We were using either APIC_DEST_PHYSICAL|APIC_DEST_LOGICAL or 0|1 to
fill in kvm_lapic_irq.dest_mode. It's fine only because in m

KVM: X86: Use APIC_DEST_* macros properly in kvm_lapic_irq.dest_mode

We were using either APIC_DEST_PHYSICAL|APIC_DEST_LOGICAL or 0|1 to
fill in kvm_lapic_irq.dest_mode. It's fine only because in most cases
when we check against dest_mode it's against APIC_DEST_PHYSICAL (which
equals to 0). However, that's not consistent. We'll have problem
when we want to start checking against APIC_DEST_LOGICAL, which does
not equals to 1.

This patch firstly introduces kvm_lapic_irq_dest_mode() helper to take
any boolean of destination mode and return the APIC_DEST_* macro.
Then, it replaces the 0|1 settings of irq.dest_mode with the helper.

Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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KVM: x86: Zero the IOAPIC scan request dest vCPUs bitmap

Not zeroing the bitmap used for identifying the destination vCPUs for an
IOAPIC scan request in fixed delivery mode could lead to waking up u

KVM: x86: Zero the IOAPIC scan request dest vCPUs bitmap

Not zeroing the bitmap used for identifying the destination vCPUs for an
IOAPIC scan request in fixed delivery mode could lead to waking up unwanted
vCPUs. This patch zeroes the vCPU bitmap before passing it to
kvm_bitmap_or_dest_vcpus(), which is responsible for setting the bitmap
with the bits corresponding to the destination vCPUs.

Fixes: 7ee30bc132c6("KVM: x86: deliver KVM IOAPIC scan request to target vCPUs")
Signed-off-by: Nitesh Narayan Lal <nitesh@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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KVM: x86: deliver KVM IOAPIC scan request to target vCPUs

In IOAPIC fixed delivery mode instead of flushing the scan
requests to all vCPUs, we should only send the requests to
vCPUs specified within

KVM: x86: deliver KVM IOAPIC scan request to target vCPUs

In IOAPIC fixed delivery mode instead of flushing the scan
requests to all vCPUs, we should only send the requests to
vCPUs specified within the destination field.

This patch introduces kvm_get_dest_vcpus_mask() API which
retrieves an array of target vCPUs by using
kvm_apic_map_get_dest_lapic() and then based on the
vcpus_idx, it sets the bit in a bitmap. However, if the above
fails kvm_get_dest_vcpus_mask() finds the target vCPUs by
traversing all available vCPUs. Followed by setting the
bits in the bitmap.

If we had different vCPUs in the previous request for the
same redirection table entry then bits corresponding to
these vCPUs are also set. This to done to keep
ioapic_handled_vectors synchronized.

This bitmap is then eventually passed on to
kvm_make_vcpus_request_mask() to generate a masked request
only for the target vCPUs.

This would enable us to reduce the latency overhead on isolated
vCPUs caused by the IPI to process due to KVM_REQ_IOAPIC_SCAN.

Suggested-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Nitesh Narayan Lal <nitesh@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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kvm: x86: ioapic and apic debug macros cleanup

The ioapic_debug and apic_debug have been not used
for years, and kvm tracepoints are enough for debugging,
so remove them as Paolo suggested.

However

kvm: x86: ioapic and apic debug macros cleanup

The ioapic_debug and apic_debug have been not used
for years, and kvm tracepoints are enough for debugging,
so remove them as Paolo suggested.

However, there may be something wrong when pv evi get/put
user, so it's better to retain some log there.

Signed-off-by: Yi Wang <wang.yi59@zte.com.cn>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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kvm: x86: Add memcg accounting to KVM allocations

There are many KVM kernel memory allocations which are tied to the life of
the VM process and should be charged to the VM process's cgroup. If the
a

kvm: x86: Add memcg accounting to KVM allocations

There are many KVM kernel memory allocations which are tied to the life of
the VM process and should be charged to the VM process's cgroup. If the
allocations aren't tied to the process, the OOM killer will not know
that killing the process will free the associated kernel memory.
Add __GFP_ACCOUNT flags to many of the allocations which are not yet being
charged to the VM process's cgroup.

Tested:
Ran all kvm-unit-tests on a 64 bit Haswell machine, the patch
introduced no new failures.
Ran a kernel memory accounting test which creates a VM to touch
memory and then checks that the kernel memory allocated for the
process is within certain bounds.
With this patch we account for much more of the vmalloc and slab memory
allocated for the VM.

There remain a few allocations which should be charged to the VM's
cgroup but are not. In x86, they include:
vcpu->arch.pio_data
There allocations are unaccounted in this patch because they are mapped
to userspace, and accounting them to a cgroup causes problems. This
should be addressed in a future patch.

Signed-off-by: Ben Gardon <bgardon@google.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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