An MSI interrupt should only be delivered to the lowest priority CPU
when it has RH=1, regardless of the delivery mode. Modified
kvm_is_dm_lowest_prio() to check for either irq->delivery_mode == APIC_DM_LOWPRI
or irq->msi_redir_hint.
Moved kvm_is_dm_lowest_prio() into lapic.h and renamed to
kvm_lowest_prio_delivery().
Changed a check in kvm_irq_delivery_to_apic_fast() from
irq->delivery_mode == APIC_DM_LOWPRI to kvm_is_dm_lowest_prio().
Signed-off-by: James Sullivan <sullivan.james.f@gmail.com>
Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Extended struct kvm_lapic_irq with bool msi_redir_hint, which will
be used to determine if the delivery of the MSI should target only
the lowest priority CPU in the logical group specified for delivery.
(In physical dest mode, the RH bit is not relevant). Initialized the value
of msi_redir_hint to true when RH=1 in kvm_set_msi_irq(), and initialized
to false in all other cases.
Added value of msi_redir_hint to a debug message dump of an IRQ in
apic_send_ipi().
Signed-off-by: James Sullivan <sullivan.james.f@gmail.com>
Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Change to u16 if they only contain data in the low 16 bits.
Change the level field to bool, since we assign 1 sometimes, but
just mask icr_low with APIC_INT_ASSERT in apic_send_ipi.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
x86 architecture defines differences between the reset and INIT sequences.
INIT does not initialize the FPU (including MMX, XMM, YMM, etc.), TSC, PMU,
MSRs (in general), MTRRs machine-check, APIC ID, APIC arbitration ID and BSP.
References (from Intel SDM):
"If the MP protocol has completed and a BSP is chosen, subsequent INITs (either
to a specific processor or system wide) do not cause the MP protocol to be
repeated." [8.4.2: MP Initialization Protocol Requirements and Restrictions]
[Table 9-1. IA-32 Processor States Following Power-up, Reset, or INIT]
"If the processor is reset by asserting the INIT# pin, the x87 FPU state is not
changed." [9.2: X87 FPU INITIALIZATION]
"The state of the local APIC following an INIT reset is the same as it is after
a power-up or hardware reset, except that the APIC ID and arbitration ID
registers are not affected." [10.4.7.3: Local APIC State After an INIT Reset
("Wait-for-SIPI" State)]
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Message-Id: <1428924848-28212-1-git-send-email-namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Introducing KVM_CAP_DISABLE_QUIRKS for disabling x86 quirks that were previous
created in order to overcome QEMU issues. Those issue were mostly result of
invalid VM BIOS. Currently there are two quirks that can be disabled:
1. KVM_QUIRK_LINT0_REENABLED - LINT0 was enabled after boot
2. KVM_QUIRK_CD_NW_CLEARED - CD and NW are cleared after boot
These two issues are already resolved in recent releases of QEMU, and would
therefore be disabled by QEMU.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Message-Id: <1428879221-29996-1-git-send-email-namit@cs.technion.ac.il>
[Report capability from KVM_CHECK_EXTENSION too. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Sparse is reporting a "we previously assumed 'src' could be null" error.
This is true as far as the static analyzer can see, but in practice only
IPIs can set shorthand to self and they also set 'src', so it's ok.
Still, move the initialization of x2apic_ipi (and thus the NULL check for
src right before the first use.
While at it, initializing ret to "false" is somewhat confusing because of
the almost immediate assigned of "true" to the same variable. Thus,
initialize it to "true" and modify it in the only path that used to use
the value from "bool ret = false". There is no change in generated code
from this change.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
ARM/ARM64: fixes for live migration, irqfd and ioeventfd support (enabling
vhost, too), page aging
s390: interrupt handling rework, allowing to inject all local interrupts
via new ioctl and to get/set the full local irq state for migration
and introspection. New ioctls to access memory by virtual address,
and to get/set the guest storage keys. SIMD support.
MIPS: FPU and MIPS SIMD Architecture (MSA) support. Includes some patches
from Ralf Baechle's MIPS tree.
x86: bugfixes (notably for pvclock, the others are small) and cleanups.
Another small latency improvement for the TSC deadline timer.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM updates from Paolo Bonzini:
"First batch of KVM changes for 4.1
The most interesting bit here is irqfd/ioeventfd support for ARM and
ARM64.
Summary:
ARM/ARM64:
fixes for live migration, irqfd and ioeventfd support (enabling
vhost, too), page aging
s390:
interrupt handling rework, allowing to inject all local interrupts
via new ioctl and to get/set the full local irq state for migration
and introspection. New ioctls to access memory by virtual address,
and to get/set the guest storage keys. SIMD support.
MIPS:
FPU and MIPS SIMD Architecture (MSA) support. Includes some
patches from Ralf Baechle's MIPS tree.
x86:
bugfixes (notably for pvclock, the others are small) and cleanups.
Another small latency improvement for the TSC deadline timer"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (146 commits)
KVM: use slowpath for cross page cached accesses
kvm: mmu: lazy collapse small sptes into large sptes
KVM: x86: Clear CR2 on VCPU reset
KVM: x86: DR0-DR3 are not clear on reset
KVM: x86: BSP in MSR_IA32_APICBASE is writable
KVM: x86: simplify kvm_apic_map
KVM: x86: avoid logical_map when it is invalid
KVM: x86: fix mixed APIC mode broadcast
KVM: x86: use MDA for interrupt matching
kvm/ppc/mpic: drop unused IRQ_testbit
KVM: nVMX: remove unnecessary double caching of MAXPHYADDR
KVM: nVMX: checks for address bits beyond MAXPHYADDR on VM-entry
KVM: x86: cache maxphyaddr CPUID leaf in struct kvm_vcpu
KVM: vmx: pass error code with internal error #2
x86: vdso: fix pvclock races with task migration
KVM: remove kvm_read_hva and kvm_read_hva_atomic
KVM: x86: optimize delivery of TSC deadline timer interrupt
KVM: x86: extract blocking logic from __vcpu_run
kvm: x86: fix x86 eflags fixed bit
KVM: s390: migrate vcpu interrupt state
...
After reset, the CPU can change the BSP, which will be used upon INIT. Reset
should return the BSP which QEMU asked for, and therefore handled accordingly.
To quote: "If the MP protocol has completed and a BSP is chosen, subsequent
INITs (either to a specific processor or system wide) do not cause the MP
protocol to be repeated."
[Intel SDM 8.4.2: MP Initialization Protocol Requirements and Restrictions]
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Message-Id: <1427933438-12782-3-git-send-email-namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
recalculate_apic_map() uses two passes over all VCPUs. This is a relic
from time when we selected a global mode in the first pass and set up
the optimized table in the second pass (to have a consistent mode).
Recent changes made mixed mode unoptimized and we can do it in one pass.
Format of logical MDA is a function of the mode, so we encode it in
apic_logical_id() and drop obsoleted variables from the struct.
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Message-Id: <1423766494-26150-5-git-send-email-rkrcmar@redhat.com>
[Add lid_bits temporary in apic_logical_id. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
We want to support mixed modes and the easiest solution is to avoid
optimizing those weird and unlikely scenarios.
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Message-Id: <1423766494-26150-4-git-send-email-rkrcmar@redhat.com>
[Add comment above KVM_APIC_MODE_* defines. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Broadcast allowed only one global APIC mode, but mixed modes are
theoretically possible. x2APIC IPI doesn't mean 0xff as broadcast,
the rest does.
x2APIC broadcasts are accepted by xAPIC. If we take SDM to be logical,
even addreses beginning with 0xff should be accepted, but real hardware
disagrees. This patch aims for simple code by considering most of real
behavior as undefined.
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Message-Id: <1423766494-26150-3-git-send-email-rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
In mixed modes, we musn't deliver xAPIC IPIs like x2APIC and vice versa.
Instead of preserving the information in apic_send_ipi(), we regain it
by converting all destinations into correct MDA in the slow path.
This allows easier reasoning about subsequent matching.
Our kvm_apic_broadcast() had an interesting design decision: it didn't
consider IOxAPIC 0xff as broadcast in x2APIC mode ...
everything worked because IOxAPIC can't set that in physical mode and
logical mode considered it as a message for first 8 VCPUs.
This patch interprets IOxAPIC 0xff as x2APIC broadcast.
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Message-Id: <1423766494-26150-2-git-send-email-rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This is needed in e.g. ARM vGIC emulation, where the MMIO handling
depends on the VCPU that does the access.
Signed-off-by: Nikolay Nikolaev <n.nikolaev@virtualopensystems.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
kvm_ioapic_update_eoi() wasn't called if directed EOI was enabled.
We need to do that for irq notifiers. (Like with edge interrupts.)
Fix it by skipping EOI broadcast only.
Bug: https://bugzilla.kernel.org/show_bug.cgi?id=82211
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Tested-by: Bandan Das <bsd@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
In commit b4eef9b36d, we started to use hwapic_isr_update() != NULL
instead of kvm_apic_vid_enabled(vcpu->kvm). This didn't work because
SVM had it defined and "apicv" path in apic_{set,clear}_isr() does not
change apic->isr_count, because it should always be 1. The initial
value of apic->isr_count was based on kvm_apic_vid_enabled(vcpu->kvm),
which is always 0 for SVM, so KVM could have injected interrupts when it
shouldn't.
Fix it by implicitly setting SVM's hwapic_isr_update to NULL and make the
initial isr_count depend on hwapic_isr_update() for good measure.
Fixes: b4eef9b36d ("kvm: x86: vmx: NULL out hwapic_isr_update() in case of !enable_apicv")
Reported-and-tested-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Common: Optional support for adding a small amount of polling on each HLT
instruction executed in the guest (or equivalent for other architectures).
This can improve latency up to 50% on some scenarios (e.g. O_DSYNC writes
or TCP_RR netperf tests). This also has to be enabled manually for now,
but the plan is to auto-tune this in the future.
ARM/ARM64: the highlights are support for GICv3 emulation and dirty page
tracking
s390: several optimizations and bugfixes. Also a first: a feature
exposed by KVM (UUID and long guest name in /proc/sysinfo) before
it is available in IBM's hypervisor! :)
MIPS: Bugfixes.
x86: Support for PML (page modification logging, a new feature in
Broadwell Xeons that speeds up dirty page tracking), nested virtualization
improvements (nested APICv---a nice optimization), usual round of emulation
fixes. There is also a new option to reduce latency of the TSC deadline
timer in the guest; this needs to be tuned manually.
Some commits are common between this pull and Catalin's; I see you
have already included his tree.
ARM has other conflicts where functions are added in the same place
by 3.19-rc and 3.20 patches. These are not large though, and entirely
within KVM.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM update from Paolo Bonzini:
"Fairly small update, but there are some interesting new features.
Common:
Optional support for adding a small amount of polling on each HLT
instruction executed in the guest (or equivalent for other
architectures). This can improve latency up to 50% on some
scenarios (e.g. O_DSYNC writes or TCP_RR netperf tests). This
also has to be enabled manually for now, but the plan is to
auto-tune this in the future.
ARM/ARM64:
The highlights are support for GICv3 emulation and dirty page
tracking
s390:
Several optimizations and bugfixes. Also a first: a feature
exposed by KVM (UUID and long guest name in /proc/sysinfo) before
it is available in IBM's hypervisor! :)
MIPS:
Bugfixes.
x86:
Support for PML (page modification logging, a new feature in
Broadwell Xeons that speeds up dirty page tracking), nested
virtualization improvements (nested APICv---a nice optimization),
usual round of emulation fixes.
There is also a new option to reduce latency of the TSC deadline
timer in the guest; this needs to be tuned manually.
Some commits are common between this pull and Catalin's; I see you
have already included his tree.
Powerpc:
Nothing yet.
The KVM/PPC changes will come in through the PPC maintainers,
because I haven't received them yet and I might end up being
offline for some part of next week"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (130 commits)
KVM: ia64: drop kvm.h from installed user headers
KVM: x86: fix build with !CONFIG_SMP
KVM: x86: emulate: correct page fault error code for NoWrite instructions
KVM: Disable compat ioctl for s390
KVM: s390: add cpu model support
KVM: s390: use facilities and cpu_id per KVM
KVM: s390/CPACF: Choose crypto control block format
s390/kernel: Update /proc/sysinfo file with Extended Name and UUID
KVM: s390: reenable LPP facility
KVM: s390: floating irqs: fix user triggerable endless loop
kvm: add halt_poll_ns module parameter
kvm: remove KVM_MMIO_SIZE
KVM: MIPS: Don't leak FPU/DSP to guest
KVM: MIPS: Disable HTW while in guest
KVM: nVMX: Enable nested posted interrupt processing
KVM: nVMX: Enable nested virtual interrupt delivery
KVM: nVMX: Enable nested apic register virtualization
KVM: nVMX: Make nested control MSRs per-cpu
KVM: nVMX: Enable nested virtualize x2apic mode
KVM: nVMX: Prepare for using hardware MSR bitmap
...
If vcpu has a interrupt in vmx non-root mode, injecting that interrupt
requires a vmexit. With posted interrupt processing, the vmexit
is not needed, and interrupts are fully taken care of by hardware.
In nested vmx, this feature avoids much more vmexits than non-nested vmx.
When L1 asks L0 to deliver L1's posted interrupt vector, and the target
VCPU is in non-root mode, we use a physical ipi to deliver POSTED_INTR_NV
to the target vCPU. Using POSTED_INTR_NV avoids unexpected interrupts
if a concurrent vmexit happens and L1's vector is different with L0's.
The IPI triggers posted interrupt processing in the target physical CPU.
In case the target vCPU was not in guest mode, complete the posted
interrupt delivery on the next entry to L2.
Signed-off-by: Wincy Van <fanwenyi0529@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
With APICv, LAPIC timer interrupt is always delivered via IRR:
apic_find_highest_irr syncs PIR to IRR.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
We forgot to re-check LAPIC after splitting the loop in commit
173beedc16 (KVM: x86: Software disabled APIC should still deliver
NMIs, 2014-11-02).
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Fixes: 173beedc16
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
We cannot hit the bug now, but future patches will expose this path.
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The majority of this patch turns
result = 0; if (CODE) result = 1; return result;
into
return CODE;
because we return bool now.
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Adds a function kvm_vcpu_set_pending_timer instead of calling
kvm_make_request in lapic.c.
Signed-off-by: Nicholas Krause <xerofoify@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add tracepoint to wait_lapic_expire.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
[Remind reader if early or late. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
For the hrtimer which emulates the tscdeadline timer in the guest,
add an option to advance expiration, and busy spin on VM-entry waiting
for the actual expiration time to elapse.
This allows achieving low latencies in cyclictest (or any scenario
which requires strict timing regarding timer expiration).
Reduces average cyclictest latency from 12us to 8us
on Core i5 desktop.
Note: this option requires tuning to find the appropriate value
for a particular hardware/guest combination. One method is to measure the
average delay between apic_timer_fn and VM-entry.
Another method is to start with 1000ns, and increase the value
in say 500ns increments until avg cyclictest numbers stop decreasing.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
In most cases calling hwapic_isr_update(), we always check if
kvm_apic_vid_enabled() == 1, but actually,
kvm_apic_vid_enabled()
-> kvm_x86_ops->vm_has_apicv()
-> vmx_vm_has_apicv() or '0' in svm case
-> return enable_apicv && irqchip_in_kernel(kvm)
So its a little cost to recall vmx_vm_has_apicv() inside
hwapic_isr_update(), here just NULL out hwapic_isr_update() in
case of !enable_apicv inside hardware_setup() then make all
related stuffs follow this. Note we don't check this under that
condition of irqchip_in_kernel() since we should make sure
definitely any caller don't work without in-kernel irqchip.
Signed-off-by: Tiejun Chen <tiejun.chen@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
While fixing an x2apic bug,
17d68b7 KVM: x86: fix guest-initiated crash with x2apic (CVE-2013-6376)
we've made only one cluster available. This means that the amount of
logically addressible x2APICs was reduced to 16 and VCPUs kept
overwriting themselves in that region, so even the first cluster wasn't
set up correctly.
This patch extends x2APIC support back to the logical_map's limit, and
keeps the CVE fixed as messages for non-present APICs are dropped.
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
They can't be violated now, but play it safe for the future.
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
x2apic allows destinations > 0xff and we don't want them delivered to
lower APICs. They are correctly handled by doing nothing.
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Physical mode can't address more than one APIC, but lowest-prio is
allowed, so we just reuse our paths.
SDM 10.6.2.1 Physical Destination:
Also, for any non-broadcast IPI or I/O subsystem initiated interrupt
with lowest priority delivery mode, software must ensure that APICs
defined in the interrupt address are present and enabled to receive
interrupts.
We could warn on top of that.
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
False from kvm_irq_delivery_to_apic_fast() means that we don't handle it
in the fast path, but we still return false in cases that were perfectly
handled, fix that.
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
0x830 MSR is 0x300 xAPIC MMIO, which is MSR_ICR.
Signed-off-by: Radim KrÄmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
x2APIC has no registers for DFR and ICR2 (see Intel SDM 10.12.1.2 "x2APIC
Register Address Space"). KVM needs to cause #GP on such accesses.
Fix it (DFR and ICR2 on read, ICR2 on write, DFR already handled on writes).
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
cs.base is declared as a __u64 variable and vector is a u32 so this
causes a static checker warning. The user indeed can set "sipi_vector"
to any u32 value in kvm_vcpu_ioctl_x86_set_vcpu_events(), but the
value should really have 8-bit precision only.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
apic_find_highest_irr assumes irr_pending is set if any vector in APIC_IRR is
set. If this assumption is broken and apicv is disabled, the injection of
interrupts may be deferred until another interrupt is delivered to the guest.
Ultimately, if no other interrupt should be injected to that vCPU, the pending
interrupt may be lost.
commit 56cc2406d6 ("KVM: nVMX: fix "acknowledge interrupt on exit" when APICv
is in use") changed the behavior of apic_clear_irr so irr_pending is cleared
after setting APIC_IRR vector. After this commit, if apic_set_irr and
apic_clear_irr run simultaneously, a race may occur, resulting in APIC_IRR
vector set, and irr_pending cleared. In the following example, assume a single
vector is set in IRR prior to calling apic_clear_irr:
apic_set_irr apic_clear_irr
------------ --------------
apic->irr_pending = true;
apic_clear_vector(...);
vec = apic_search_irr(apic);
// => vec == -1
apic_set_vector(...);
apic->irr_pending = (vec != -1);
// => apic->irr_pending == false
Nonetheless, it appears the race might even occur prior to this commit:
apic_set_irr apic_clear_irr
------------ --------------
apic->irr_pending = true;
apic->irr_pending = false;
apic_clear_vector(...);
if (apic_search_irr(apic) != -1)
apic->irr_pending = true;
// => apic->irr_pending == false
apic_set_vector(...);
Fixing this issue by:
1. Restoring the previous behavior of apic_clear_irr: clear irr_pending, call
apic_clear_vector, and then if APIC_IRR is non-zero, set irr_pending.
2. On apic_set_irr: first call apic_set_vector, then set irr_pending.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Logical destination mode can be used to send NMI IPIs even when all
APICs are software disabled, so if all APICs are software disabled we
should still look at the DFRs.
So the DFRs should all be the same, even if some or all APICs are
software disabled. However, the SDM does not say this, so tweak
the logic as follows:
- if one APIC is enabled and has LDR != 0, use that one to build the map.
This picks the right DFR in case an OS is only setting it for the
software-enabled APICs, or in case an OS is using logical addressing
on some APICs while leaving the rest in reset state (using LDR was
suggested by Radim).
- if all APICs are disabled, pick a random one to build the map.
We use the last one with LDR != 0 for simplicity.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Currently, the APIC logical map does not consider VCPUs whose local-apic is
software-disabled. However, NMIs, INIT, etc. should still be delivered to such
VCPUs. Therefore, the APIC mode should first be determined, and then the map,
considering all VCPUs should be constructed.
To address this issue, first find the APIC mode, and only then construct the
logical map.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
APIC base relocation is unsupported by KVM. If anyone uses it, the least should
be to report a warning in the hypervisor.
Note that KVM-unit-tests uses this feature for some reason, so running the
tests triggers the warning.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
A bug was reported as follows: when running Windows 7 32-bit guests on qemu-kvm,
sometimes the guests run into blue screen during reboot. The problem was that a
guest's RVI was not cleared when it rebooted. This patch has fixed the problem.
Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Signed-off-by: Yang Zhang <yang.z.zhang@intel.com>
Tested-by: Rongrong Liu <rongrongx.liu@intel.com>, Da Chun <ngugc@qq.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
We mirror a subset of these registers in separate variables.
Using them directly should be faster.
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
APIC-write VM exits are "trap-like": they save CS:RIP values for the
instruction after the write, and more importantly, the handler will
already see the new value in the virtual-APIC page. This means that
apic_reg_write cannot use kvm_apic_get_reg to omit timer cancelation
when mode changes.
timer_mode_mask shouldn't be changing as it depends on cpuid.
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
APIC-write VM exits are "trap-like": they save CS:RIP values for the
instruction after the write, and more importantly, the handler will
already see the new value in the virtual-APIC page.
This caused a bug if you used KVM_SET_IRQCHIP to set the SW-enabled bit
in the SPIV register. The chain of events is as follows:
* When the irqchip is added to the destination VM, the apic_sw_disabled
static key is incremented (1)
* When the KVM_SET_IRQCHIP ioctl is invoked, it is decremented (0)
* When the guest disables the bit in the SPIV register, e.g. as part of
shutdown, apic_set_spiv does not notice the change and the static key is
_not_ incremented.
* When the guest is destroyed, the static key is decremented (-1),
resulting in this trace:
WARNING: at kernel/jump_label.c:81 __static_key_slow_dec+0xa6/0xb0()
jump label: negative count!
[<ffffffff816bf898>] dump_stack+0x19/0x1b
[<ffffffff8107c6f1>] warn_slowpath_common+0x61/0x80
[<ffffffff8107c76c>] warn_slowpath_fmt+0x5c/0x80
[<ffffffff811931e6>] __static_key_slow_dec+0xa6/0xb0
[<ffffffff81193226>] static_key_slow_dec_deferred+0x16/0x20
[<ffffffffa0637698>] kvm_free_lapic+0x88/0xa0 [kvm]
[<ffffffffa061c63e>] kvm_arch_vcpu_uninit+0x2e/0xe0 [kvm]
[<ffffffffa05ff301>] kvm_vcpu_uninit+0x21/0x40 [kvm]
[<ffffffffa067cec7>] vmx_free_vcpu+0x47/0x70 [kvm_intel]
[<ffffffffa061bc50>] kvm_arch_vcpu_free+0x50/0x60 [kvm]
[<ffffffffa061ca22>] kvm_arch_destroy_vm+0x102/0x260 [kvm]
[<ffffffff810b68fd>] ? synchronize_srcu+0x1d/0x20
[<ffffffffa06030d1>] kvm_put_kvm+0xe1/0x1c0 [kvm]
[<ffffffffa06036f8>] kvm_vcpu_release+0x18/0x20 [kvm]
[<ffffffff81215c62>] __fput+0x102/0x310
[<ffffffff81215f4e>] ____fput+0xe/0x10
[<ffffffff810ab664>] task_work_run+0xb4/0xe0
[<ffffffff81083944>] do_exit+0x304/0xc60
[<ffffffff816c8dfc>] ? _raw_spin_unlock_irq+0x2c/0x50
[<ffffffff810fd22d>] ? trace_hardirqs_on_caller+0xfd/0x1c0
[<ffffffff8108432c>] do_group_exit+0x4c/0xc0
[<ffffffff810843b4>] SyS_exit_group+0x14/0x20
[<ffffffff816d33a9>] system_call_fastpath+0x16/0x1b
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The check in kvm_set_lapic_tscdeadline_msr() was trying to prevent a
situation where we lose a pending deadline timer in a MSR write.
Losing it is fine, because it effectively occurs before the timer fired,
so we should be able to cancel or postpone it.
Another problem comes from interaction with QEMU, or other userspace
that can set deadline MSR without a good reason, when timer is already
pending: one guest's deadline request results in more than one
interrupt because one is injected immediately on MSR write from
userspace and one through hrtimer later.
The solution is to remove the injection when replacing a pending timer
and to improve the usual QEMU path, we inject without a hrtimer when the
deadline has already passed.
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Reported-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Make the code reusable.
If the timer was already pending, we shouldn't be waiting in a queue,
so wake_up can be skipped, simplifying the path.
There is no 'reinject' case => the comment is removed.
Current race behaves correctly.
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM does not deliver x2APIC broadcast messages with physical mode. Intel SDM
(10.12.9 ICR Operation in x2APIC Mode) states: "A destination ID value of
FFFF_FFFFH is used for broadcast of interrupts in both logical destination and
physical destination modes."
In addition, the local-apic enables cluster mode broadcast. As Intel SDM
10.6.2.2 says: "Broadcast to all local APICs is achieved by setting all
destination bits to one." This patch enables cluster mode broadcast.
The fix tries to combine broadcast in different modes through a unified code.
One rare case occurs when the source of IPI has its APIC disabled. In such
case, the source can still issue IPIs, but since the source is not obliged to
have the same LAPIC mode as the enabled ones, we cannot rely on it.
Since it is a rare case, it is unoptimized and done on the slow-path.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Reviewed-by: Wanpeng Li <wanpeng.li@linux.intel.com>
[As per Radim's review, use unsigned int for X2APIC_BROADCAST, return bool from
kvm_apic_broadcast. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Initially the tracepoint was added only to the APIC_DM_FIXED case,
also because it reported coalesced interrupts that only made sense
for that case. However, the coalesced argument is not used anymore
and tracing other delivery modes is useful, so hoist the call out
of the switch statement.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Currently, recalculate_apic_map ignores vcpus whose lapic is software disabled
through the spurious interrupt vector. However, once it is re-enabled, the map
is not recalculated. Therefore, if the guest OS configured DFR while lapic is
software-disabled, the map may be incorrect. This patch recalculates apic map
after software enabling the lapic.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Intel SDM 10.5.4.1 says "When the timer generates an interrupt, it disarms
itself and clears the IA32_TSC_DEADLINE MSR".
This patch clears the MSR upon timer interrupt delivery which delivered on
deadline mode. Since the MSR may be reconfigured while an interrupt is
pending, causing the new value to be overriden, pending timer interrupts are
checked before setting a new deadline.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
