With all the necessary GICv3 emulation code in place, we can now
connect the code to the GICv3 backend in the kernel.
The LR register handling is different depending on the emulated GIC
model, so provide different implementations for each.
Also allow non-v2-compatible GICv3 implementations (which don't
provide MMIO regions for the virtual CPU interface in the DT), but
restrict those hosts to support GICv3 guests only.
If the device tree provides a GICv2 compatible GICV resource entry,
but that one is faulty, just disable the GICv2 emulation and let the
user use at least the GICv3 emulation for guests.
To provide proper support for the legacy KVM_CREATE_IRQCHIP ioctl,
note virtual GICv2 compatibility in struct vgic_params and use it
on creating a VGICv2.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
While the generation of a (virtual) inter-processor interrupt (SGI)
on a GICv2 works by writing to a MMIO register, GICv3 uses the system
register ICC_SGI1R_EL1 to trigger them.
Add a trap handler function that calls the new SGI register handler
in the GICv3 code. As ICC_SRE_EL1.SRE at this point is still always 0,
this will not trap yet, but will only be used later when all the data
structures have been initialized properly.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
With everything separated and prepared, we implement a model of a
GICv3 distributor and redistributors by using the existing framework
to provide handler functions for each register group.
Currently we limit the emulation to a model enforcing a single
security state, with SRE==1 (forcing system register access) and
ARE==1 (allowing more than 8 VCPUs).
We share some of the functions provided for GICv2 emulation, but take
the different ways of addressing (v)CPUs into account.
Save and restore is currently not implemented.
Similar to the split-off of the GICv2 specific code, the new emulation
code goes into a new file (vgic-v3-emul.c).
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
For a GICv2 there is always only one (v)CPU involved: the one that
does the access. On a GICv3 the access to a CPU redistributor is
memory-mapped, but not banked, so the (v)CPU affected is determined by
looking at the MMIO address region being accessed.
To allow passing the affected CPU into the accessors later, extend
struct kvm_exit_mmio to add an opaque private pointer parameter.
The current GICv2 emulation just does not use it.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
vgic.c is currently a mixture of generic vGIC emulation code and
functions specific to emulating a GICv2. To ease the addition of
GICv3, split off strictly v2 specific parts into a new file
vgic-v2-emul.c.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
-------
As the diff isn't always obvious here (and to aid eventual rebases),
here is a list of high-level changes done to the code:
* added new file to respective arm/arm64 Makefiles
* moved GICv2 specific functions to vgic-v2-emul.c:
- handle_mmio_misc()
- handle_mmio_set_enable_reg()
- handle_mmio_clear_enable_reg()
- handle_mmio_set_pending_reg()
- handle_mmio_clear_pending_reg()
- handle_mmio_priority_reg()
- vgic_get_target_reg()
- vgic_set_target_reg()
- handle_mmio_target_reg()
- handle_mmio_cfg_reg()
- handle_mmio_sgi_reg()
- vgic_v2_unqueue_sgi()
- read_set_clear_sgi_pend_reg()
- write_set_clear_sgi_pend_reg()
- handle_mmio_sgi_set()
- handle_mmio_sgi_clear()
- vgic_v2_handle_mmio()
- vgic_get_sgi_sources()
- vgic_dispatch_sgi()
- vgic_v2_queue_sgi()
- vgic_v2_map_resources()
- vgic_v2_init()
- vgic_v2_add_sgi_source()
- vgic_v2_init_model()
- vgic_v2_init_emulation()
- handle_cpu_mmio_misc()
- handle_mmio_abpr()
- handle_cpu_mmio_ident()
- vgic_attr_regs_access()
- vgic_create() (renamed to vgic_v2_create())
- vgic_destroy() (renamed to vgic_v2_destroy())
- vgic_has_attr() (renamed to vgic_v2_has_attr())
- vgic_set_attr() (renamed to vgic_v2_set_attr())
- vgic_get_attr() (renamed to vgic_v2_get_attr())
- struct kvm_mmio_range vgic_dist_ranges[]
- struct kvm_mmio_range vgic_cpu_ranges[]
- struct kvm_device_ops kvm_arm_vgic_v2_ops {}
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
vgic.c is currently a mixture of generic vGIC emulation code and
functions specific to emulating a GICv2. To ease the addition of
GICv3 later, we create new header file vgic.h, which holds constants
and prototypes of commonly used functions.
Rename some identifiers to avoid name space clutter.
I removed the long-standing comment about using the kvm_io_bus API
to tackle the GIC register ranges, as it wouldn't be a win for us
anymore.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
-------
As the diff isn't always obvious here (and to aid eventual rebases),
here is a list of high-level changes done to the code:
* moved definitions and prototypes from vgic.c to vgic.h:
- VGIC_ADDR_UNDEF
- ACCESS_{READ,WRITE}_*
- vgic_init()
- vgic_update_state()
- vgic_kick_vcpus()
- vgic_get_vmcr()
- vgic_set_vmcr()
- struct mmio_range {} (renamed to struct kvm_mmio_range)
* removed static keyword and exported prototype in vgic.h:
- vgic_bitmap_get_reg()
- vgic_bitmap_set_irq_val()
- vgic_bitmap_get_shared_map()
- vgic_bytemap_get_reg()
- vgic_dist_irq_set_pending()
- vgic_dist_irq_clear_pending()
- vgic_cpu_irq_clear()
- vgic_reg_access()
- handle_mmio_raz_wi()
- vgic_handle_enable_reg()
- vgic_handle_set_pending_reg()
- vgic_handle_clear_pending_reg()
- vgic_handle_cfg_reg()
- vgic_unqueue_irqs()
- find_matching_range() (renamed to vgic_find_range)
- vgic_handle_mmio_range()
- vgic_update_state()
- vgic_get_vmcr()
- vgic_set_vmcr()
- vgic_queue_irq()
- vgic_kick_vcpus()
- vgic_init()
- vgic_v2_init_emulation()
- vgic_has_attr_regs()
- vgic_set_common_attr()
- vgic_get_common_attr()
- vgic_destroy()
- vgic_create()
* moved functions to vgic.h (static inline):
- mmio_data_read()
- mmio_data_write()
- is_in_range()
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
vgic_set_attr() and vgic_get_attr() contain both code specific for
the emulated GIC as well as code for the userland facing, generic
part of the GIC.
Split the guest GIC facing code of from the generic part to allow
easier splitting later.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
The MMIO accessors for GICD_I[CS]ENABLER, GICD_I[CS]PENDR and
GICD_ICFGR behave very similar for GICv2 and GICv3, although the way
the affected VCPU is determined differs.
Since we need them to access the registers from three different
places in the future, we factor out a generic, backend-facing
implementation and use small wrappers in the current GICv2 emulation.
This will ease adding GICv3 accessors later.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
ICC_SRE_EL1 is a system register allowing msr/mrs accesses to the
GIC CPU interface for EL1 (guests). Currently we force it to 0, but
for proper GICv3 support we have to allow guests to use it (depending
on their selected virtual GIC model).
So add ICC_SRE_EL1 to the list of saved/restored registers on a
world switch, but actually disallow a guest to change it by only
restoring a fixed, once-initialized value.
This value depends on the GIC model userland has chosen for a guest.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Currently the maximum number of vCPUs supported is a global value
limited by the used GIC model. GICv3 will lift this limit, but we
still need to observe it for guests using GICv2.
So the maximum number of vCPUs is per-VM value, depending on the
GIC model the guest uses.
Store and check the value in struct kvm_arch, but keep it down to
8 for now.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
To check whether the vGIC was already initialized, we currently check
the GICH base address for not being NULL. Since with GICv3 we may
get along without this address, lets use the irqchip_in_kernel()
function to detect an already initialized vGIC.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Currently we unconditionally register the GICv2 emulation device
during the host's KVM initialization. Since with GICv3 support we
may end up with only v2 or only v3 or both supported, we move the
registration into the GIC probing function, where we will later know
which combination is valid.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Currently we only have one virtual GIC model supported, so all guests
use the same emulation code. With the addition of another model we
end up with different guests using potentially different vGIC models,
so we have to split up some functions to be per VM.
Introduce a vgic_vm_ops struct to hold function pointers for those
functions that are different and provide the necessary code to
initialize them.
Also split up the vgic_init() function to separate out VGIC model
specific functionality into a separate function, which will later be
different for a GICv3 model.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Some GICv3 registers can and will be accessed as 64 bit registers.
Currently the register handling code can only deal with 32 bit
accesses, so we do two consecutive calls to cover this.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Currently we only need to deal with one MMIO region for the GIC
emulation (the GICv2 distributor), but we soon need to extend this.
Refactor the existing code to allow easier addition of different
ranges without code duplication.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
With the introduction of a second emulated GIC model we need to let
userspace specify the GIC model to use for each VM. Pass the
userspace provided value down into the vGIC code and store it there
to differentiate later.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
kvm_get_dirty_log() provides generic handling of dirty bitmap, currently reused
by several architectures. Building on that we intrdoduce
kvm_get_dirty_log_protect() adding write protection to mark these pages dirty
for future write access, before next KVM_GET_DIRTY_LOG ioctl call from user
space.
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Mario Smarduch <m.smarduch@samsung.com>
Allow architectures to override the generic kvm_flush_remote_tlbs()
function via HAVE_KVM_ARCH_TLB_FLUSH_ALL. ARMv7 will need this to
provide its own TLB flush interface.
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Mario Smarduch <m.smarduch@samsung.com>
Since the advent of VGIC dynamic initialization, this latter is
initialized quite late on the first vcpu run or "on-demand", when
injecting an IRQ or when the guest sets its registers.
This initialization could be initiated explicitly much earlier
by the users-space, as soon as it has provided the requested
dimensioning parameters.
This patch adds a new entry to the VGIC KVM device that allows
the user to manually request the VGIC init:
- a new KVM_DEV_ARM_VGIC_GRP_CTRL group is introduced.
- Its first attribute is KVM_DEV_ARM_VGIC_CTRL_INIT
The rationale behind introducing a group is to be able to add other
controls later on, if needed.
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
To be more explicit on vgic initialization failure, -ENODEV is
returned by vgic_init when no online vcpus can be found at init.
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Several hypervisors need MSR auto load/restore feature.
We read MSRs from VM-entry MSR load area which specified by L1,
and load them via kvm_set_msr in the nested entry.
When nested exit occurs, we get MSRs via kvm_get_msr, writing
them to L1`s MSR store area. After this, we read MSRs from VM-exit
MSR load area, and load them via kvm_set_msr.
Signed-off-by: Wincy Van <fanwenyi0529@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Modifying a non-existent slot is not allowed. Also check that the
first loop doesn't move a deleted slot beyond the used part of
the mslots array.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Before commit 0e60b0799f (kvm: change memslot sorting rule from size
to GFN, 2014-12-01), the memslots' sorting key was npages, meaning
that a valid memslot couldn't have its sorting key equal to zero.
On the other hand, a valid memslot can have base_gfn == 0, and invalid
memslots are identified by base_gfn == npages == 0.
Because of this, commit 0e60b0799f broke the invariant that invalid
memslots are at the end of the mslots array. When a memslot with
base_gfn == 0 was created, any invalid memslot before it were left
in place.
This can be fixed by changing the insertion to use a ">=" comparison
instead of "<=", but some care is needed to avoid breaking the case
of deleting a memslot; see the comment in update_memslots.
Thanks to Tiejun Chen for posting an initial patch for this bug.
Reported-by: Jamie Heilman <jamie@audible.transient.net>
Reported-by: Andy Lutomirski <luto@amacapital.net>
Tested-by: Jamie Heilman <jamie@audible.transient.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
- spring cleaning: removed support for IA64, and for hardware-assisted
virtualization on the PPC970
- ARM, PPC, s390 all had only small fixes
For x86:
- small performance improvements (though only on weird guests)
- usual round of hardware-compliancy fixes from Nadav
- APICv fixes
- XSAVES support for hosts and guests. XSAVES hosts were broken because
the (non-KVM) XSAVES patches inadvertently changed the KVM userspace
ABI whenever XSAVES was enabled; hence, this part is going to stable.
Guest support is just a matter of exposing the feature and CPUID leaves
support.
Right now KVM is broken for PPC BookE in your tree (doesn't compile).
I'll reply to the pull request with a patch, please apply it either
before the pull request or in the merge commit, in order to preserve
bisectability somewhat.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM update from Paolo Bonzini:
"3.19 changes for KVM:
- spring cleaning: removed support for IA64, and for hardware-
assisted virtualization on the PPC970
- ARM, PPC, s390 all had only small fixes
For x86:
- small performance improvements (though only on weird guests)
- usual round of hardware-compliancy fixes from Nadav
- APICv fixes
- XSAVES support for hosts and guests. XSAVES hosts were broken
because the (non-KVM) XSAVES patches inadvertently changed the KVM
userspace ABI whenever XSAVES was enabled; hence, this part is
going to stable. Guest support is just a matter of exposing the
feature and CPUID leaves support"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (179 commits)
KVM: move APIC types to arch/x86/
KVM: PPC: Book3S: Enable in-kernel XICS emulation by default
KVM: PPC: Book3S HV: Improve H_CONFER implementation
KVM: PPC: Book3S HV: Fix endianness of instruction obtained from HEIR register
KVM: PPC: Book3S HV: Remove code for PPC970 processors
KVM: PPC: Book3S HV: Tracepoints for KVM HV guest interactions
KVM: PPC: Book3S HV: Simplify locking around stolen time calculations
arch: powerpc: kvm: book3s_paired_singles.c: Remove unused function
arch: powerpc: kvm: book3s_pr.c: Remove unused function
arch: powerpc: kvm: book3s.c: Remove some unused functions
arch: powerpc: kvm: book3s_32_mmu.c: Remove unused function
KVM: PPC: Book3S HV: Check wait conditions before sleeping in kvmppc_vcore_blocked
KVM: PPC: Book3S HV: ptes are big endian
KVM: PPC: Book3S HV: Fix inaccuracies in ICP emulation for H_IPI
KVM: PPC: Book3S HV: Fix KSM memory corruption
KVM: PPC: Book3S HV: Fix an issue where guest is paused on receiving HMI
KVM: PPC: Book3S HV: Fix computation of tlbie operand
KVM: PPC: Book3S HV: Add missing HPTE unlock
KVM: PPC: BookE: Improve irq inject tracepoint
arm/arm64: KVM: Require in-kernel vgic for the arch timers
...
problems, clarifies VCPU init, and fixes a regression concerning the
VGIC init flow.
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Merge tag 'kvm-arm-for-3.19-take2' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD
Second round of changes for KVM for arm/arm64 for v3.19; fixes reboot
problems, clarifies VCPU init, and fixes a regression concerning the
VGIC init flow.
Conflicts:
arch/ia64/kvm/kvm-ia64.c [deleted in HEAD and modified in kvmarm]
It is curently possible to run a VM with architected timers support
without creating an in-kernel VGIC, which will result in interrupts from
the virtual timer going nowhere.
To address this issue, move the architected timers initialization to the
time when we run a VCPU for the first time, and then only initialize
(and enable) the architected timers if we have a properly created and
initialized in-kernel VGIC.
When injecting interrupts from the virtual timer to the vgic, the
current setup should ensure that this never calls an on-demand init of
the VGIC, which is the only call path that could return an error from
kvm_vgic_inject_irq(), so capture the return value and raise a warning
if there's an error there.
We also change the kvm_timer_init() function from returning an int to be
a void function, since the function always succeeds.
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Userspace assumes that it can wire up IRQ injections after having
created all VCPUs and after having created the VGIC, but potentially
before starting the first VCPU. This can currently lead to lost IRQs
because the state of that IRQ injection is not stored anywhere and we
don't return an error to userspace.
We haven't seen this problem manifest itself yet, presumably because
guests reset the devices on boot, but this could cause issues with
migration and other non-standard startup configurations.
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Some code paths will need to check to see if the internal state of the
vgic has been initialized (such as when creating new VCPUs), so
introduce such a macro that checks the nr_cpus field which is set when
the vgic has been initialized.
Also set nr_cpus = 0 in kvm_vgic_destroy, because the error path in
vgic_init() will call this function, and code should never errornously
assume the vgic to be properly initialized after an error.
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
The vgic_initialized() macro currently returns the state of the
vgic->ready flag, which indicates if the vgic is ready to be used when
running a VM, not specifically if its internal state has been
initialized.
Rename the macro accordingly in preparation for a more nuanced
initialization flow.
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
VGIC initialization currently happens in three phases:
(1) kvm_vgic_create() (triggered by userspace GIC creation)
(2) vgic_init_maps() (triggered by userspace GIC register read/write
requests, or from kvm_vgic_init() if not already run)
(3) kvm_vgic_init() (triggered by first VM run)
We were doing initialization of some state to correspond with the
state of a freshly-reset GIC in kvm_vgic_init(); this is too late,
since it will overwrite changes made by userspace using the
register access APIs before the VM is run. Move this initialization
earlier, into the vgic_init_maps() phase.
This fixes a bug where QEMU could successfully restore a saved
VM state snapshot into a VM that had already been run, but could
not restore it "from cold" using the -loadvm command line option
(the symptoms being that the restored VM would run but interrupts
were ignored).
Finally rename vgic_init_maps to vgic_init and renamed kvm_vgic_init to
kvm_vgic_map_resources.
[ This patch is originally written by Peter Maydell, but I have
modified it somewhat heavily, renaming various bits and moving code
around. If something is broken, I am to be blamed. - Christoffer ]
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
We currently track the pid of the task that runs the VCPU in vcpu_load.
If a yield to that VCPU is triggered while the PID of the wrong thread
is active, the wrong thread might receive a yield, but this will most
likely not help the executing thread at all. Instead, if we only track
the pid on the KVM_RUN ioctl, there are two possibilities:
1) the thread that did a non-KVM_RUN ioctl is holding a mutex that
the VCPU thread is waiting for. In this case, the VCPU thread is not
runnable, but we also do not do a wrong yield.
2) the thread that did a non-KVM_RUN ioctl is sleeping, or doing
something that does not block the VCPU thread. In this case, the
VCPU thread can receive the directed yield correctly.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
CC: Rik van Riel <riel@redhat.com>
CC: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
CC: Michael Mueller <mimu@linux.vnet.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
kvm_enter_guest() has to be called with preemption disabled and will
set PF_VCPU. Current code takes PF_VCPU as a hint that the VCPU thread
is running and therefore needs no yield.
However, the check on PF_VCPU is wrong on s390, where preemption has
to stay enabled in order to correctly process page faults. Thus,
s390 reenables preemption and starts to execute the guest. The thread
might be scheduled out between kvm_enter_guest() and kvm_exit_guest(),
resulting in PF_VCPU being set but not being run. When this happens,
the opportunity for directed yield is missed.
However, this check is done already in kvm_vcpu_on_spin before calling
kvm_vcpu_yield_loop:
if (!ACCESS_ONCE(vcpu->preempted))
continue;
so the check on PF_VCPU is superfluous in general, and this patch
removes it.
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Current linear search doesn't scale well when
large amount of memslots is used and looked up slot
is not in the beginning memslots array.
Taking in account that memslots don't overlap, it's
possible to switch sorting order of memslots array from
'npages' to 'base_gfn' and use binary search for
memslot lookup by GFN.
As result of switching to binary search lookup times
are reduced with large amount of memslots.
Following is a table of search_memslot() cycles
during WS2008R2 guest boot.
boot, boot + ~10 min
mostly same of using it,
slot lookup randomized lookup
max average average
cycles cycles cycles
13 slots : 1450 28 30
13 slots : 1400 30 40
binary search
117 slots : 13000 30 460
117 slots : 2000 35 180
binary search
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
it will allow to use binary search for GFN -> memslot
lookups, reducing lookup cost with large slots amount.
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
UP/DOWN shift loops will shift array in needed
direction and stop at place where new slot should
be placed regardless of old slot size.
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
if number of pages haven't changed sorting algorithm
will do nothing, so there is no need to do extra check
to avoid entering sorting logic.
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This reverts commit 85c8555ff0 ("KVM: check for !is_zero_pfn() in
kvm_is_mmio_pfn()") and renames the function to kvm_is_reserved_pfn.
The problem being addressed by the patch above was that some ARM code
based the memory mapping attributes of a pfn on the return value of
kvm_is_mmio_pfn(), whose name indeed suggests that such pfns should
be mapped as device memory.
However, kvm_is_mmio_pfn() doesn't do quite what it says on the tin,
and the existing non-ARM users were already using it in a way which
suggests that its name should probably have been 'kvm_is_reserved_pfn'
from the beginning, e.g., whether or not to call get_page/put_page on
it etc. This means that returning false for the zero page is a mistake
and the patch above should be reverted.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
If we detect another vCPU is running we just exit and return 0 as if we
succesfully created the VGIC, but the VGIC wouldn't actual be created.
This shouldn't break in-kernel behavior because the kernel will not
observe the failed the attempt to create the VGIC, but userspace could
be rightfully confused.
Cc: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
When call kvm_vgic_inject_irq to inject interrupt, we can known which
vcpu the interrupt for by the irq_num and the cpuid. So we should just
kick this vcpu to avoid iterating through all.
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Shannon Zhao <zhaoshenglong@huawei.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
When 'injecting' an edge-triggered interrupt with a falling edge we
shouldn't clear the pending state on the distributor. In fact, we
don't, because the check in vgic_validate_injection would prevent us
from ever reaching this bit of code.
Remove the unreachable snippet.
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
This reverts commit 85c8555ff0 ("KVM: check for !is_zero_pfn() in
kvm_is_mmio_pfn()") and renames the function to kvm_is_reserved_pfn.
The problem being addressed by the patch above was that some ARM code
based the memory mapping attributes of a pfn on the return value of
kvm_is_mmio_pfn(), whose name indeed suggests that such pfns should
be mapped as device memory.
However, kvm_is_mmio_pfn() doesn't do quite what it says on the tin,
and the existing non-ARM users were already using it in a way which
suggests that its name should probably have been 'kvm_is_reserved_pfn'
from the beginning, e.g., whether or not to call get_page/put_page on
it etc. This means that returning false for the zero page is a mistake
and the patch above should be reverted.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
When vgic_update_irq_pending with level-sensitive false, it is need to
deactivates an interrupt, and, it can go to out directly.
Here return a false value, because it will be not need to kick.
Signed-off-by: wanghaibin <wanghaibin.wang@huawei.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Now that ia64 is gone, we can hide deprecated device assignment in x86.
Notable changes:
- kvm_vm_ioctl_assigned_device() was moved to x86/kvm_arch_vm_ioctl()
The easy parts were removed from generic kvm code, remaining
- kvm_iommu_(un)map_pages() would require new code to be moved
- struct kvm_assigned_dev_kernel depends on struct kvm_irq_ack_notifier
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
ia64 does not need them anymore. Ack notifiers become x86-specific
too.
Suggested-by: Gleb Natapov <gleb@kernel.org>
Reviewed-by: Radim Krcmar <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM for ia64 has been marked as broken not just once, but twice even,
and the last patch from the maintainer is now roughly 5 years old.
Time for it to rest in peace.
Acked-by: Gleb Natapov <gleb@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The update_memslots invocation is only needed in one case. Make
the code clearer by moving it to __kvm_set_memory_region, and
removing the wrapper around insert_memslot.
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The two kmemdup invocations can be unified. I find that the new
placement of the comment makes it easier to see what happens.
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This completes the optimization from the previous patch, by
removing the KVM_MEM_SLOTS_NUM-iteration loop from insert_memslot.
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
memslots is a sorted array. When a slot is changed, heapsort (lib/sort.c)
would take O(n log n) time to update it; an optimized insertion sort will
only cost O(n) on an array with just one item out of order.
Replace sort() with a custom sort that takes advantage of memslots usage
pattern and the known position of the changed slot.
performance change of 128 memslots insertions with gradually increasing
size (the worst case):
heap sort custom sort
max: 249747 2500 cycles
with custom sort alg taking ~98% less then original
update time.
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
commit 72dc67a696 ("KVM: remove the usage of the mmap_sem for the protection of the memory slots.")
changed the lock which will be taken. This should be reflected in the function
commentary.
Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
