commit 3491caf275 ("KVM: halt_polling: provide a way to qualify
wakeups during poll") added more aggressive shrinking of the
polling interval if the wakeup did not match some criteria. This
still allows to keep polling enabled if the polling time was
smaller that the current max poll time (block_ns <= vcpu->halt_poll_ns).
Performance measurement shows that even more aggressive shrinking
(shrink polling on any invalid wakeup) reduces absolute and relative
(to the workload) CPU usage even further.
Cc: David Matlack <dmatlack@google.com>
Cc: Wanpeng Li <kernellwp@gmail.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
on s390 we disabled the halt polling with commit 920552b213
("KVM: disable halt_poll_ns as default for s390x"), as floating
interrupts would let all CPUs have a successful poll, resulting
in much higher CPU usage (on otherwise idle systems).
With the improved selection of polls we can now retry halt polling.
Performance measurements with different choices like 25,50,80,100,200
microseconds showed that 80 microseconds seems to improve several cases
without increasing the CPU costs too much. Higher values would improve
the performance even more but increased the cpu time as well.
So let's start small and use this value of 80 microseconds on s390 until
we have a better understanding of cost/benefit of higher values.
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Some wakeups should not be considered a sucessful poll. For example on
s390 I/O interrupts are usually floating, which means that _ALL_ CPUs
would be considered runnable - letting all vCPUs poll all the time for
transactional like workload, even if one vCPU would be enough.
This can result in huge CPU usage for large guests.
This patch lets architectures provide a way to qualify wakeups if they
should be considered a good/bad wakeups in regard to polls.
For s390 the implementation will fence of halt polling for anything but
known good, single vCPU events. The s390 implementation for floating
interrupts does a wakeup for one vCPU, but the interrupt will be delivered
by whatever CPU checks first for a pending interrupt. We prefer the
woken up CPU by marking the poll of this CPU as "good" poll.
This code will also mark several other wakeup reasons like IPI or
expired timers as "good". This will of course also mark some events as
not sucessful. As KVM on z runs always as a 2nd level hypervisor,
we prefer to not poll, unless we are really sure, though.
This patch successfully limits the CPU usage for cases like uperf 1byte
transactional ping pong workload or wakeup heavy workload like OLTP
while still providing a proper speedup.
This also introduced a new vcpu stat "halt_poll_no_tuning" that marks
wakeups that are considered not good for polling.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Radim Krčmář <rkrcmar@redhat.com> (for an earlier version)
Cc: David Matlack <dmatlack@google.com>
Cc: Wanpeng Li <kernellwp@gmail.com>
[Rename config symbol. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Commit c9a5eccac1 ("kvm/eventfd: add arch-specific set_irq",
2015-10-16) added the possibility for architecture-specific code
to handle the generation of virtual interrupts in atomic context
where possible, without having to schedule a work function.
Since we can easily generate virtual interrupts on XICS without
having to do anything worse than take a spinlock, we define a
kvm_arch_set_irq_inatomic() for XICS. We also remove kvm_set_msi()
since it is not used any more.
The one slightly tricky thing is that with the new interface, we
don't get told whether the interrupt is an MSI (or other edge
sensitive interrupt) vs. level-sensitive. The difference as far
as interrupt generation is concerned is that for LSIs we have to
set the asserted flag so it will continue to fire until it is
explicitly cleared.
In fact the XICS code gets told which interrupts are LSIs by userspace
when it configures the interrupt via the KVM_DEV_XICS_GRP_SOURCES
attribute group on the XICS device. To store this information, we add
a new "lsi" field to struct ics_irq_state. With that we can also do a
better job of returning accurate values when reading the attribute
group.
Signed-off-by: Paul Mackerras <paulus@samba.org>
If we don't support a mechanism for bypassing IRQs, don't register as
a consumer. This eliminates meaningless dev_info()s when the connect
fails between producer and consumer, such as on AMD systems where
kvm_x86_ops->update_pi_irte is not implemented
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
A NULL token is meaningless and can only lead to unintended problems.
Error on registration with a NULL token, ignore de-registrations with
a NULL token.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The KVM_MAX_VCPUS define provides the maximum number of vCPUs per guest, and
also the upper limit for vCPU ids. This is okay for all archs except PowerPC
which can have higher ids, depending on the cpu/core/thread topology. In the
worst case (single threaded guest, host with 8 threads per core), it limits
the maximum number of vCPUS to KVM_MAX_VCPUS / 8.
This patch separates the vCPU numbering from the total number of vCPUs, with
the introduction of KVM_MAX_VCPU_ID, as the maximal valid value for vCPU ids
plus one.
The corresponding KVM_CAP_MAX_VCPU_ID allows userspace to validate vCPU ids
before passing them to KVM_CREATE_VCPU.
This patch only implements KVM_MAX_VCPU_ID with a specific value for PowerPC.
Other archs continue to return KVM_MAX_VCPUS instead.
Suggested-by: Radim Krcmar <rkrcmar@redhat.com>
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Commit c896939f7c ("KVM: use heuristic for fast VCPU lookup by id") added
a return path that prevents vcpu ids to exceed KVM_MAX_VCPUS. This is a
problem for powerpc where vcpu ids can grow up to 8*KVM_MAX_VCPUS.
This patch simply reverses the logic so that we only try fast path if the
vcpu id can be tried as an index in kvm->vcpus[]. The slow path is not
affected by the change.
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reworks our stage 2 page table handling to have page table manipulation
macros separate from those of the host systems as the underlying
hardware page tables can be configured to be noticably different in
layout from the stage 1 page tables used by the host.
Adds 16K page size support based on the above.
Adds a generic firmware probing layer for the timer and GIC so that KVM
initializes using the same logic based on both ACPI and FDT.
Finally adds support for hardware updating of the access flag.
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Merge tag 'kvm-arm-for-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD
KVM/ARM Changes for Linux v4.7
Reworks our stage 2 page table handling to have page table manipulation
macros separate from those of the host systems as the underlying
hardware page tables can be configured to be noticably different in
layout from the stage 1 page tables used by the host.
Adds 16K page size support based on the above.
Adds a generic firmware probing layer for the timer and GIC so that KVM
initializes using the same logic based on both ACPI and FDT.
Finally adds support for hardware updating of the access flag.
When CONFIG_KVM_XICS is enabled, CPU_UP_PREPARE and other macros for
CPU states in linux/cpu.h are needed by arch/powerpc/kvm/book3s_hv.c.
Otherwise, build error as below is seen:
gwshan@gwshan:~/sandbox/l$ make arch/powerpc/kvm/book3s_hv.o
:
CC arch/powerpc/kvm/book3s_hv.o
arch/powerpc/kvm/book3s_hv.c: In function ‘kvmppc_cpu_notify’:
arch/powerpc/kvm/book3s_hv.c:3072:7: error: ‘CPU_UP_PREPARE’ \
undeclared (first use in this function)
This fixes the issue introduced by commit <6f3bb80944> ("KVM: PPC:
Book3S HV: kvmppc_host_rm_ops - handle offlining CPUs").
Fixes: 6f3bb80944
Cc: stable@vger.kernel.org # v4.6
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Reviewed-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
When the guest does a sign-extending load instruction (such as lha
or lwa) to an emulated MMIO location, it results in a call to
kvmppc_handle_loads() in the host. That function sets the
vcpu->arch.mmio_sign_extend flag and calls kvmppc_handle_load()
to do the rest of the work. However, kvmppc_handle_load() sets
the mmio_sign_extend flag to 0 unconditionally, so the sign
extension never gets done.
To fix this, we rename kvmppc_handle_load to __kvmppc_handle_load
and add an explicit parameter to indicate whether sign extension
is required. kvmppc_handle_load() and kvmppc_handle_loads() then
become 1-line functions that just call __kvmppc_handle_load()
with the extra parameter.
Reported-by: Bin Lu <lblulb@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
When XICS_DBG is enabled, gcc produces format errors. This fixes
formats to match passed values types.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Until now, when we connect gdb to the QEMU gdb-server, the
single-step mode is not managed.
This patch adds this, only for kvm-pr:
If KVM_GUESTDBG_SINGLESTEP is set, we enable single-step trace bit in the
MSR (MSR_SE) just before the __kvmppc_vcpu_run(), and disable it just after.
In kvmppc_handle_exit_pr, instead of routing the interrupt to
the guest, we return to host, with KVM_EXIT_DEBUG reason.
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
- Use hardware provided information about facility bits that do not
need any hypervisor activitiy
- Add missing documentation for KVM_CAP_S390_RI
- Some updates/fixes for handling cpu models and facilities
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Merge tag 'kvm-s390-next-4.7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD
KVM: s390: features and fixes for 4.7 part2
- Use hardware provided information about facility bits that do not
need any hypervisor activitiy
- Add missing documentation for KVM_CAP_S390_RI
- Some updates/fixes for handling cpu models and facilities
Add the necessary hazard barriers after disabling the FPU in
kvm_lose_fpu(), just to be safe.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim KrÄmář" <rkrcmar@redhat.com>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reading the KVM_CAP_MIPS_FPU capability returns cpu_has_fpu, however
this uses smp_processor_id() to read the current CPU capabilities (since
some old MIPS systems could have FPUs present on only a subset of CPUs).
We don't support any such systems, so work around the warning by using
raw_cpu_has_fpu instead.
We should probably instead claim not to support FPU at all if any one
CPU is lacking an FPU, but this should do for now.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim KrÄmář" <rkrcmar@redhat.com>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
There are a couple of places in KVM fault handling code which implicitly
use smp_processor_id() via kvm_mips_get_kernel_asid() and
kvm_mips_get_user_asid() from preemptable context. This is unsafe as a
preemption could cause the guest kernel ASID to be changed, resulting in
a host TLB entry being written with the wrong ASID.
Fix by disabling preemption around the kvm_mips_get_*_asid() call and
the corresponding kvm_mips_host_tlb_write().
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim KrÄmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Writing CP0_Compare clears the timer interrupt pending bit
(CP0_Cause.TI), but this wasn't being done atomically. If a timer
interrupt raced with the write of the guest CP0_Compare, the timer
interrupt could end up being pending even though the new CP0_Compare is
nowhere near CP0_Count.
We were already updating the hrtimer expiry with
kvm_mips_update_hrtimer(), which used both kvm_mips_freeze_hrtimer() and
kvm_mips_resume_hrtimer(). Close the race window by expanding out
kvm_mips_update_hrtimer(), and clearing CP0_Cause.TI and setting
CP0_Compare between the freeze and resume. Since the pending timer
interrupt should not be cleared when CP0_Compare is written via the KVM
user API, an ack argument is added to distinguish the source of the
write.
Fixes: e30492bbe9 ("MIPS: KVM: Rewrite count/compare timer emulation")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim KrÄmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Cc: <stable@vger.kernel.org> # 3.16.x-
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
There's a particularly narrow and subtle race condition when the
software emulated guest timer is frozen which can allow a guest timer
interrupt to be missed.
This happens due to the hrtimer expiry being inexact, so very
occasionally the freeze time will be after the moment when the emulated
CP0_Count transitions to the same value as CP0_Compare (so an IRQ should
be generated), but before the moment when the hrtimer is due to expire
(so no IRQ is generated). The IRQ won't be generated when the timer is
resumed either, since the resume CP0_Count will already match CP0_Compare.
With VZ guests in particular this is far more likely to happen, since
the soft timer may be frozen frequently in order to restore the timer
state to the hardware guest timer. This happens after 5-10 hours of
guest soak testing, resulting in an overflow in guest kernel timekeeping
calculations, hanging the guest. A more focussed test case to
intentionally hit the race (with the help of a new hypcall to cause the
timer state to migrated between hardware & software) hits the condition
fairly reliably within around 30 seconds.
Instead of relying purely on the inexact hrtimer expiry to determine
whether an IRQ should be generated, read the guest CP0_Compare and
directly check whether the freeze time is before or after it. Only if
CP0_Count is on or after CP0_Compare do we check the hrtimer expiry to
determine whether the last IRQ has already been generated (which will
have pushed back the expiry by one timer period).
Fixes: e30492bbe9 ("MIPS: KVM: Rewrite count/compare timer emulation")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim KrÄmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Cc: <stable@vger.kernel.org> # 3.16.x-
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The ARMv8.1 architecture extensions introduce support for hardware
updates of the access and dirty information in page table entries. With
VTCR_EL2.HA enabled (bit 21), when the CPU accesses an IPA with the
PTE_AF bit cleared in the stage 2 page table, instead of raising an
Access Flag fault to EL2 the CPU sets the actual page table entry bit
(10). To ensure that kernel modifications to the page table do not
inadvertently revert a bit set by hardware updates, certain Stage 2
software pte/pmd operations must be performed atomically.
The main user of the AF bit is the kvm_age_hva() mechanism. The
kvm_age_hva_handler() function performs a "test and clear young" action
on the pte/pmd. This needs to be atomic in respect of automatic hardware
updates of the AF bit. Since the AF bit is in the same position for both
Stage 1 and Stage 2, the patch reuses the existing
ptep_test_and_clear_young() functionality if
__HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG is defined. Otherwise, the
existing pte_young/pte_mkold mechanism is preserved.
The kvm_set_s2pte_readonly() (and the corresponding pmd equivalent) have
to perform atomic modifications in order to avoid a race with updates of
the AF bit. The arm64 implementation has been re-written using
exclusives.
Currently, kvm_set_s2pte_writable() (and pmd equivalent) take a pointer
argument and modify the pte/pmd in place. However, these functions are
only used on local variables rather than actual page table entries, so
it makes more sense to follow the pte_mkwrite() approach for stage 1
attributes. The change to kvm_s2pte_mkwrite() makes it clear that these
functions do not modify the actual page table entries.
The (pte|pmd)_mkyoung() uses on Stage 2 entries (setting the AF bit
explicitly) do not need to be modified since hardware updates of the
dirty status are not supported by KVM, so there is no possibility of
losing such information.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
When a guest is initializing, KVM provides facility bits that can be
successfully used by the guest. It's done by applying
kvm_s390_fac_list_mask mask on host facility bits stored by the STFLE
instruction. Facility bits can be one of two kinds: it's either a
hypervisor managed bit or non-hypervisor managed.
The hardware provides information which bits need special handling.
Let's automatically passthrough to guests new facility bits, that
don't require hypervisor support.
Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Eric Farman <farman@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Let's add hypervisor-managed facility-apportionment indications field to
SCLP structs. KVM will use it to reduce maintenance cost of
Non-Hypervisor-Managed facility bits.
Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Eric Farman <farman@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Some facility bits are in a range that is defined to be "ok for guests
without any necessary hypervisor changes". Enable those bits.
Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
We forgot to document that capability, let's add documentation.
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Some hardware variants will round the ibc value up/down themselves,
others will report a validity intercept. Let's always round it up/down.
This patch will also make sure that the ibc is set to 0 in case we don't
have ibc support (lowest_ibc == 0).
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
We only have one cpuid for all VCPUs, so let's directly use the one in the
cpu model. Also always store it directly as u64, no need for struct cpuid.
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
If we don't have SIGP SENSE RUNNING STATUS enabled for the guest, let's
not enable interpretation so we can correctly report an invalid order.
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Only enable PFMF interpretation if the necessary facility (EDAT1) is
available, otherwise the pfmf handler in priv.c will inject an exception
Reviewed-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
While we can not fully fence of the Nonquiescing Key-Setting facility,
we should as try our best to hide it.
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
We should never inject an exception after we manually rewound the PSW
(to retry the ESSA instruction in this case). This will mess up the PSW.
So this never worked and therefore never really triggered.
Looking at the details, we don't even have to perform any validity checks.
1. Bits 52-63 of an entry are stored as 0 by the hardware.
2. We are dealing with absolute addresses but only check for the prefix
starting at address 0. This isn't correct and doesn't make much sense,
cpus could still zap the prefix of other cpus. But as prefix pages
cannot be swapped out without a notifier being called for the affected
VCPU, a zap can never remove a protected prefix.
Reviewed-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Guest should only trust data to be valid when version haven't changed
before and after reads of steal time. Besides not changing, it has to
be an even number. Hypervisor may write an odd number to version field
to indicate that an update is in progress.
kvm_steal_clock() in guest has already done the read side, make write
side in hypervisor more robust by following the above rule.
Reviewed-by: Wincy Van <fanwenyi0529@gmail.com>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
The only call of arch_timer_get_timecounter (in KVM) has been removed.
Signed-off-by: Julien Grall <julien.grall@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Currently, the firmware tables are parsed 2 times: once in the GIC
drivers, the other time when initializing the vGIC. It means code
duplication and make more tedious to add the support for another
firmware table (like ACPI).
Use the recently introduced helper gic_get_kvm_info() to get
information about the virtual GIC.
With this change, the virtual GIC becomes agnostic to the firmware
table and KVM will be able to initialize the vGIC on ACPI.
Signed-off-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
The firmware table is currently parsed by the virtual timer code in
order to retrieve the virtual timer interrupt. However, this is already
done by the arch timer driver.
To avoid code duplication, use the newly function arch_timer_get_kvm_info()
which return all the information required by the virtual timer code.
Signed-off-by: Julien Grall <julien.grall@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Fill up the recently introduced gic_kvm_info with the hardware
information used for virtualization.
Signed-off-by: Julien Grall <julien.grall@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
The ACPI code requires to use global variables in order to collect
information from the tables.
To make clear those variables are ACPI specific, gather all of them in a
single structure.
Furthermore, even if some of the variables are not marked with
__initdata, they are all only used during the initialization. Therefore,
the new variable, which hold the structure, can be marked with
__initdata.
Signed-off-by: Julien Grall <julien.grall@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Currently, most of the pr_* messages in the GICv3 driver don't have a
prefix. Add one to make clear where the messages come from.
Signed-off-by: Julien Grall <julien.grall@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
For now, the firmware tables are parsed 2 times: once in the GIC
drivers, the other timer when initializing the vGIC. It means code
duplication and make more tedious to add the support for another
firmware table (like ACPI).
Introduce a new structure and set of helpers to get/set the virtual GIC
information. Also fill up the structure for GICv2.
Signed-off-by: Julien Grall <julien.grall@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
The ACPI code requires to use global variables in order to collect
information from the tables.
For now, a single global variable is used, but more will be added in a
subsequent patch. To make clear they are ACPI specific, gather all the
information in a single structure.
Signed-off-by: Julien Grall <julien.grall@arm.com>
Acked-by: Christofer Dall <christoffer.dall@linaro.org>
Acked-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Currently, the firmware table is parsed by the virtual timer code in
order to retrieve the virtual timer interrupt. However, this is already
done by the arch timer driver.
To avoid code duplication, extend arch_timer_kvm_info to get the virtual
IRQ.
Note that the KVM code will be modified in a subsequent patch.
Signed-off-by: Julien Grall <julien.grall@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Introduce a structure which are filled up by the arch timer driver and
used by the virtual timer in KVM.
The first member of this structure will be the timecounter. More members
will be added later.
A stub for the new helper isn't introduced because KVM requires the arch
timer for both ARM64 and ARM32.
The function arch_timer_get_timecounter is kept for the time being and
will be dropped in a subsequent patch.
Signed-off-by: Julien Grall <julien.grall@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Commit d28bc9dd25 reversed the order of two lines which initialize cr0,
allowing the current (old) cr0 value to mess up vcpu initialization.
This was observed in the checks for cr0 X86_CR0_WP bit in the context of
kvm_mmu_reset_context(). Besides, setting vcpu->arch.cr0 after vmx_set_cr0()
is completely redundant. Change the order back to ensure proper vcpu
initialization.
The combination of booting with ovmf firmware when guest vcpus > 1 and kvm's
ept=N option being set results in a VM-entry failure. This patch fixes that.
Fixes: d28bc9dd25 ("KVM: x86: INIT and reset sequences are different")
Cc: stable@vger.kernel.org
Signed-off-by: Bruce Rogers <brogers@suse.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
The ARM architecture mandates that when changing a page table entry
from a valid entry to another valid entry, an invalid entry is first
written, TLB invalidated, and only then the new entry being written.
The current code doesn't respect this, directly writing the new
entry and only then invalidating TLBs. Let's fix it up.
Cc: <stable@vger.kernel.org>
Reported-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Now that we can handle stage-2 page tables independent
of the host page table levels, wire up the 16K page
support.
Cc: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Now that we don't have any fake page table levels for arm64,
cleanup the common code to get rid of the dead code.
Cc: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
On arm64, the hardware supports concatenation of upto 16 tables,
at entry level for stage2 translations and we make use that whenever
possible. This could lead to reduced number of translation levels than
the normal (stage1 table) table. Also, since the IPA(40bit) is smaller
than the some of the supported VA_BITS (e.g, 48bit), there could be
different number of levels in stage-1 vs stage-2 tables. To reuse the
kernel host page table walker for stage2 we have been using a fake
software page table level, not known to the hardware. But with 16K
translations, there could be upto 2 fake software levels (with 48bit VA
and 40bit IPA), which complicates the code. Hence, we want to get rid of
the hack.
Now that we have explicit accessors for hyp vs stage2 page tables,
define the stage2 walker helpers accordingly based on the actual
table used by the hardware.
Once we know the number of translation levels used by the hardware,
it is merely a job of defining the helpers based on whether a
particular level is folded or not, looking at the number of levels.
Some facts before we calculate the translation levels:
1) Smallest page size supported by arm64 is 4K.
2) The minimum number of bits resolved at any page table level
is (PAGE_SHIFT - 3) at intermediate levels.
Both of them implies, minimum number of bits required for a level
change is 9.
Since we can concatenate upto 16 tables at stage2 entry, the total
number of page table levels used by the hardware for resolving N bits
is same as that for (N - 4) bits (with concatenation), as there cannot
be a level in between (N, N-4) as per the above rules.
Hence, we have
STAGE2_PGTABLE_LEVELS = PGTABLE_LEVELS(KVM_PHYS_SHIFT - 4)
With the current IPA limit (40bit), for all supported translations
and VA_BITS, we have the following condition (even for 36bit VA with
16K page size):
CONFIG_PGTABLE_LEVELS >= STAGE2_PGTABLE_LEVELS.
So, for e.g, if PUD is present in stage2, it is present in the hyp(host).
Hence, we fall back to the host definition if we find that a level is not
folded. Otherwise we redefine it accordingly. A build time check is added
to make sure the above condition holds. If this condition breaks in future,
we can rearrange the host level helpers and fix our code easily.
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Suravee Suthikulpanit
Christian Borntraeger
Paolo Bonzini
Paul Mackerras
Alex Williamson
Greg Kurz
Gavin Shan
Alexey Kardashevskiy
Laurent Vivier
James Hogan
Catalin Marinas
Borislav Petkov
Alexander Yarygin
David Hildenbrand
Wanpeng Li
Julien Grall
Bruce Rogers
Marc Zyngier
Eric Engestrom
Suzuki K Poulose