25 Sep, 2015
1 commit
-
We observed some performance degradation on s390x with dynamic
halt polling. Until we can provide a proper fix, let's enable
halt_poll_ns as default only for supported architectures.Architectures are now free to set their own halt_poll_ns
default value.Signed-off-by: David Hildenbrand
Signed-off-by: Paolo Bonzini
17 Sep, 2015
2 commits
-
…it/kvmarm/kvmarm into kvm-master
Second set of KVM/ARM changes for 4.3-rc2
- Workaround for a Cortex-A57 erratum
- Bug fix for the debugging infrastructure
- Fix for 32bit guests with more than 4GB of address space
on a 32bit host
- A number of fixes for the (unusual) case when we don't use
the in-kernel GIC emulation
- Removal of ThumbEE handling on arm64, since these have been
dropped from the architecture before anyone actually ever
built a CPU
- Remove the KVM_ARM_MAX_VCPUS limitation which has become
fairly pointless -
This patch removes config option of KVM_ARM_MAX_VCPUS,
and like other ARCHs, just choose the maximum allowed
value from hardware, and follows the reasons:1) from distribution view, the option has to be
defined as the max allowed value because it need to
meet all kinds of virtulization applications and
need to support most of SoCs;2) using a bigger value doesn't introduce extra memory
consumption, and the help text in Kconfig isn't accurate
because kvm_vpu structure isn't allocated until request
of creating VCPU is sent from QEMU;3) the main effect is that the field of vcpus[] in 'struct kvm'
becomes a bit bigger(sizeof(void *) per vcpu) and need more cache
lines to hold the structure, but 'struct kvm' is one generic struct,
and it has worked well on other ARCHs already in this way. Also,
the world switch frequecy is often low, for example, it is ~2000
when running kernel building load in VM from APM xgene KVM host,
so the effect is very small, and the difference can't be observed
in my test at all.Cc: Dann Frazier
Signed-off-by: Ming Lei
Reviewed-by: Christoffer Dall
Signed-off-by: Marc Zyngier
16 Sep, 2015
1 commit
-
This new statistic can help diagnosing VCPUs that, for any reason,
trigger bad behavior of halt_poll_ns autotuning.For example, say halt_poll_ns = 480000, and wakeups are spaced exactly
like 479us, 481us, 479us, 481us. Then KVM always fails polling and wastes
10+20+40+80+160+320+480 = 1110 microseconds out of every
479+481+479+481+479+481+479 = 3359 microseconds. The VCPU then
is consuming about 30% more CPU than it would use without
polling. This would show as an abnormally high number of
attempted polling compared to the successful polls.Acked-by: Christian Borntraeger <
Reviewed-by: David Matlack
Signed-off-by: Paolo Bonzini
15 Sep, 2015
5 commits
-
Currently, if we had a zero length mmio eventfd assigned on
KVM_MMIO_BUS. It will never be found by kvm_io_bus_cmp() since it
always compares the kvm_io_range() with the length that guest
wrote. This will cause e.g for vhost, kick will be trapped by qemu
userspace instead of vhost. Fixing this by using zero length if an
iodevice is zero length.Cc: stable@vger.kernel.org
Cc: Gleb Natapov
Cc: Paolo Bonzini
Signed-off-by: Jason Wang
Reviewed-by: Cornelia Huck
Signed-off-by: Paolo Bonzini -
We register wildcard mmio eventfd on two buses, once for KVM_MMIO_BUS
and once on KVM_FAST_MMIO_BUS but with a single iodev
instance. This will lead to an issue: kvm_io_bus_destroy() knows
nothing about the devices on two buses pointing to a single dev. Which
will lead to double free[1] during exit. Fix this by allocating two
instances of iodevs then registering one on KVM_MMIO_BUS and another
on KVM_FAST_MMIO_BUS.CPU: 1 PID: 2894 Comm: qemu-system-x86 Not tainted 3.19.0-26-generic #28-Ubuntu
Hardware name: LENOVO 2356BG6/2356BG6, BIOS G7ET96WW (2.56 ) 09/12/2013
task: ffff88009ae0c4b0 ti: ffff88020e7f0000 task.ti: ffff88020e7f0000
RIP: 0010:[] [] ioeventfd_release+0x28/0x60 [kvm]
RSP: 0018:ffff88020e7f3bc8 EFLAGS: 00010292
RAX: dead000000200200 RBX: ffff8801ec19c900 RCX: 000000018200016d
RDX: ffff8801ec19cf80 RSI: ffffea0008bf1d40 RDI: ffff8801ec19c900
RBP: ffff88020e7f3bd8 R08: 000000002fc75a01 R09: 000000018200016d
R10: ffffffffc07df6ae R11: ffff88022fc75a98 R12: ffff88021e7cc000
R13: ffff88021e7cca48 R14: ffff88021e7cca50 R15: ffff8801ec19c880
FS: 00007fc1ee3e6700(0000) GS:ffff88023e240000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8f389d8000 CR3: 000000023dc13000 CR4: 00000000001427e0
Stack:
ffff88021e7cc000 0000000000000000 ffff88020e7f3be8 ffffffffc07e2622
ffff88020e7f3c38 ffffffffc07df69a ffff880232524160 ffff88020e792d80
0000000000000000 ffff880219b78c00 0000000000000008 ffff8802321686a8
Call Trace:
[] ioeventfd_destructor+0x12/0x20 [kvm]
[] kvm_put_kvm+0xca/0x210 [kvm]
[] kvm_vcpu_release+0x18/0x20 [kvm]
[] __fput+0xe7/0x250
[] ____fput+0xe/0x10
[] task_work_run+0xd4/0xf0
[] do_exit+0x368/0xa50
[] ? recalc_sigpending+0x1f/0x60
[] do_group_exit+0x45/0xb0
[] get_signal+0x291/0x750
[] do_signal+0x28/0xab0
[] ? do_futex+0xdb/0x5d0
[] ? __wake_up_locked_key+0x18/0x20
[] ? SyS_futex+0x76/0x170
[] do_notify_resume+0x69/0xb0
[] int_signal+0x12/0x17
Code: 5d c3 90 0f 1f 44 00 00 55 48 89 e5 53 48 89 fb 48 83 ec 08 48 8b 7f 20 e8 06 d6 a5 c0 48 8b 43 08 48 8b 13 48 89 df 48 89 42 08 89 10 48 b8 00 01 10 00 00
RIP [] ioeventfd_release+0x28/0x60 [kvm]
RSPCc: stable@vger.kernel.org
Cc: Gleb Natapov
Cc: Paolo Bonzini
Signed-off-by: Jason Wang
Reviewed-by: Cornelia Huck
Signed-off-by: Paolo Bonzini -
This patch factors out core eventfd assign/deassign logic and leaves
the argument checking and bus index selection to callers.Cc: stable@vger.kernel.org
Cc: Gleb Natapov
Cc: Paolo Bonzini
Signed-off-by: Jason Wang
Reviewed-by: Cornelia Huck
Signed-off-by: Paolo Bonzini -
We only want zero length mmio eventfd to be registered on
KVM_FAST_MMIO_BUS. So check this explicitly when arg->len is zero to
make sure this.Cc: stable@vger.kernel.org
Cc: Gleb Natapov
Cc: Paolo Bonzini
Signed-off-by: Jason Wang
Reviewed-by: Cornelia Huck
Signed-off-by: Paolo Bonzini -
After 'commit 0b8ba4a2b658 ("KVM: fix checkpatch.pl errors in
kvm/coalesced_mmio.h")', the declaration of the two function will exceed 80
characters.This patch reduces the TAPs to make each line in 80 characters.
Signed-off-by: Wei Yang
Signed-off-by: Paolo Bonzini
14 Sep, 2015
2 commits
-
…/kvmarm/kvmarm into kvm-master
KVM/ARM changes for 4.3-rc2
- Fix timer interrupt injection after the rework
that went in during the merge window
- Reset the timer to zero on reboot
- Make sure the TCR_EL2 RES1 bits are really set to 1
- Fix a PSCI affinity bug for non-existing vcpus -
If there is already some polling ongoing, it's impossible to disable the
polling, since as soon as somebody sets halt_poll_ns to 0, polling will
never stop, as grow and shrink are only handled if halt_poll_ns is != 0.This patch fix it by reset vcpu->halt_poll_ns in order to stop polling
when polling is disabled.Reported-by: Christian Borntraeger
Signed-off-by: Wanpeng Li
Signed-off-by: Paolo Bonzini
11 Sep, 2015
2 commits
-
Merge third patch-bomb from Andrew Morton:
- even more of the rest of MM
- lib/ updates
- checkpatch updates
- small changes to a few scruffy filesystems
- kmod fixes/cleanups
- kexec updates
- a dma-mapping cleanup series from hch
* emailed patches from Andrew Morton : (81 commits)
dma-mapping: consolidate dma_set_mask
dma-mapping: consolidate dma_supported
dma-mapping: cosolidate dma_mapping_error
dma-mapping: consolidate dma_{alloc,free}_noncoherent
dma-mapping: consolidate dma_{alloc,free}_{attrs,coherent}
mm: use vma_is_anonymous() in create_huge_pmd() and wp_huge_pmd()
mm: make sure all file VMAs have ->vm_ops set
mm, mpx: add "vm_flags_t vm_flags" arg to do_mmap_pgoff()
mm: mark most vm_operations_struct const
namei: fix warning while make xmldocs caused by namei.c
ipc: convert invalid scenarios to use WARN_ON
zlib_deflate/deftree: remove bi_reverse()
lib/decompress_unlzma: Do a NULL check for pointer
lib/decompressors: use real out buf size for gunzip with kernel
fs/affs: make root lookup from blkdev logical size
sysctl: fix int -> unsigned long assignments in INT_MIN case
kexec: export KERNEL_IMAGE_SIZE to vmcoreinfo
kexec: align crash_notes allocation to make it be inside one physical page
kexec: remove unnecessary test in kimage_alloc_crash_control_pages()
kexec: split kexec_load syscall from kexec core code
... -
In the scope of the idle memory tracking feature, which is introduced by
the following patch, we need to clear the referenced/accessed bit not only
in primary, but also in secondary ptes. The latter is required in order
to estimate wss of KVM VMs. At the same time we want to avoid flushing
tlb, because it is quite expensive and it won't really affect the final
result.Currently, there is no function for clearing pte young bit that would meet
our requirements, so this patch introduces one. To achieve that we have
to add a new mmu-notifier callback, clear_young, since there is no method
for testing-and-clearing a secondary pte w/o flushing tlb. The new method
is not mandatory and currently only implemented by KVM.Signed-off-by: Vladimir Davydov
Reviewed-by: Andres Lagar-Cavilla
Acked-by: Paolo Bonzini
Cc: Minchan Kim
Cc: Raghavendra K T
Cc: Johannes Weiner
Cc: Michal Hocko
Cc: Greg Thelen
Cc: Michel Lespinasse
Cc: David Rientjes
Cc: Pavel Emelyanov
Cc: Cyrill Gorcunov
Cc: Jonathan Corbet
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
08 Sep, 2015
1 commit
-
We were taking the exit path after checking ue->flags and return value
of setup_routing_entry(), but 'e' was not freed incase of a failure.Signed-off-by: Sudip Mukherjee
Signed-off-by: Paolo Bonzini
06 Sep, 2015
3 commits
-
Tracepoint for dynamic halt_pool_ns, fired on every potential change.
Signed-off-by: Wanpeng Li
Signed-off-by: Paolo Bonzini -
There is a downside of always-poll since poll is still happened for idle
vCPUs which can waste cpu usage. This patchset add the ability to adjust
halt_poll_ns dynamically, to grow halt_poll_ns when shot halt is detected,
and to shrink halt_poll_ns when long halt is detected.There are two new kernel parameters for changing the halt_poll_ns:
halt_poll_ns_grow and halt_poll_ns_shrink.no-poll always-poll dynamic-poll
-----------------------------------------------------------------------
Idle (nohz) vCPU %c0 0.15% 0.3% 0.2%
Idle (250HZ) vCPU %c0 1.1% 4.6%~14% 1.2%
TCP_RR latency 34us 27us 26.7us"Idle (X) vCPU %c0" is the percent of time the physical cpu spent in
c0 over 60 seconds (each vCPU is pinned to a pCPU). (nohz) means the
guest was tickless. (250HZ) means the guest was ticking at 250HZ.The big win is with ticking operating systems. Running the linux guest
with nohz=off (and HZ=250), we save 3.4%~12.8% CPUs/second and get close
to no-polling overhead levels by using the dynamic-poll. The savings
should be even higher for higher frequency ticks.Suggested-by: David Matlack
Signed-off-by: Wanpeng Li
[Simplify the patch. - Paolo]
Signed-off-by: Paolo Bonzini -
Change halt_poll_ns into per-VCPU variable, seeded from module parameter,
to allow greater flexibility.Signed-off-by: Wanpeng Li
Signed-off-by: Paolo Bonzini
04 Sep, 2015
2 commits
-
Provide a better quality of implementation and be architecture compliant
on ARMv7 for the architected timer by resetting the CNTV_CTL to 0 on
reset of the timer.This change alone fixes the UEFI reset issue reported by Laszlo back in
February.Cc: Laszlo Ersek
Cc: Ard Biesheuvel
Cc: Drew Jones
Cc: Wei Huang
Cc: Peter Maydell
Reviewed-by: Marc Zyngier
Signed-off-by: Christoffer Dall
Signed-off-by: Marc Zyngier -
We currently set the physical active state only when we *inject* a new
pending virtual interrupt, but this is actually not correct, because we
could have been preempted and run something else on the system that
resets the active state to clear. This causes us to run the VM with the
timer set to fire, but without setting the physical active state.The solution is to always check the LR configurations, and we if have a
mapped interrupt in the LR in either the pending or active state
(virtual), then set the physical active state.Acked-by: Marc Zyngier
Signed-off-by: Christoffer Dall
Signed-off-by: Marc Zyngier
23 Aug, 2015
1 commit
-
Patch queue for ppc - 2015-08-22
Highlights for KVM PPC this time around:
- Book3S: A few bug fixes
- Book3S: Allow micro-threading on POWER8
12 Aug, 2015
7 commits
-
In order to remove the crude hack where we sneak the masked bit
into the timer's control register, make use of the phys_irq_map
API control the active state of the interrupt.This causes some limited changes to allow for potential error
propagation.Reviewed-by: Christoffer Dall
Signed-off-by: Marc Zyngier -
Virtual interrupts mapped to a HW interrupt should only be triggered
from inside the kernel. Otherwise, you could end up confusing the
kernel (and the GIC's) state machine.Rearrange the injection path so that kvm_vgic_inject_irq is
used for non-mapped interrupts, and kvm_vgic_inject_mapped_irq is
used for mapped interrupts. The latter should only be called from
inside the kernel (timer, irqfd).Reviewed-by: Christoffer Dall
Signed-off-by: Marc Zyngier -
In order to control the active state of an interrupt, introduce
a pair of accessors allowing the state to be set/queried.This only affects the logical state, and the HW state will only be
applied at world-switch time.Acked-by: Christoffer Dall
Signed-off-by: Marc Zyngier -
To allow a HW interrupt to be injected into a guest, we lookup the
guest virtual interrupt in the irq_phys_map list, and if we have
a match, encode both interrupts in the LR.We also mark the interrupt as "active" at the host distributor level.
On guest EOI on the virtual interrupt, the host interrupt will be
deactivated.Reviewed-by: Christoffer Dall
Signed-off-by: Marc Zyngier -
In order to be able to feed physical interrupts to a guest, we need
to be able to establish the virtual-physical mapping between the two
worlds.The mappings are kept in a set of RCU lists, indexed by virtual interrupts.
Reviewed-by: Christoffer Dall
Signed-off-by: Marc Zyngier -
We only set the irq_queued flag for level interrupts, meaning
that "!vgic_irq_is_queued(vcpu, irq)" is a good enough predicate
for all interrupts.This will allow us to inject edge HW interrupts, for which the
state ACTIVE+PENDING is not allowed.Reviewed-by: Christoffer Dall
Signed-off-by: Marc Zyngier -
Now that struct vgic_lr supports the LR_HW bit and carries a hwirq
field, we can encode that information into the list registers.This patch provides implementations for both GICv2 and GICv3.
Reviewed-by: Christoffer Dall
Signed-off-by: Marc Zyngier
30 Jul, 2015
1 commit
-
Signed-off-by: Paolo Bonzini
29 Jul, 2015
1 commit
-
This is another remnant of ia64 support.
Signed-off-by: Paolo Bonzini
10 Jul, 2015
1 commit
-
If there are no assigned devices, the guest PAT are not providing
any useful information and can be overridden to writeback; VMX
always does this because it has the "IPAT" bit in its extended
page table entries, but SVM does not have anything similar.
Hook into VFIO and legacy device assignment so that they
provide this information to KVM.Reviewed-by: Alex Williamson
Tested-by: Joerg Roedel
Signed-off-by: Paolo Bonzini
04 Jul, 2015
1 commit
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Commit 1cde2930e154 ("sched/preempt: Add static_key() to preempt_notifiers")
had two problems. First, the preempt-notifier API needs to sleep with the
addition of the static_key, we do however need to hold off preemption
while modifying the preempt notifier list, otherwise a preemption could
observe an inconsistent list state. KVM correctly registers and
unregisters preempt notifiers with preemption disabled, so the sleep
caused dmesg splats.Second, KVM registers and unregisters preemption notifiers very often
(in vcpu_load/vcpu_put). With a single uniprocessor guest the static key
would move between 0 and 1 continuously, hitting the slow path on every
userspace exit.To fix this, wrap the static_key inc/dec in a new API, and call it from
KVM.Fixes: 1cde2930e154 ("sched/preempt: Add static_key() to preempt_notifiers")
Reported-by: Pontus Fuchs
Reported-by: Takashi Iwai
Tested-by: Takashi Iwai
Signed-off-by: Peter Zijlstra (Intel)
Signed-off-by: Paolo Bonzini
25 Jun, 2015
1 commit
-
Pull arm64 updates from Catalin Marinas:
"Mostly refactoring/clean-up:- CPU ops and PSCI (Power State Coordination Interface) refactoring
following the merging of the arm64 ACPI support, together with
handling of Trusted (secure) OS instances- Using fixmap for permanent FDT mapping, removing the initial dtb
placement requirements (within 512MB from the start of the kernel
image). This required moving the FDT self reservation out of the
memreserve processing- Idmap (1:1 mapping used for MMU on/off) handling clean-up
- Removing flush_cache_all() - not safe on ARM unless the MMU is off.
Last stages of CPU power down/up are handled by firmware already- "Alternatives" (run-time code patching) refactoring and support for
immediate branch patching, GICv3 CPU interface access- User faults handling clean-up
And some fixes:
- Fix for VDSO building with broken ELF toolchains
- Fix another case of init_mm.pgd usage for user mappings (during
ASID roll-over broadcasting)- Fix for FPSIMD reloading after CPU hotplug
- Fix for missing syscall trace exit
- Workaround for .inst asm bug
- Compat fix for switching the user tls tpidr_el0 register"
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (42 commits)
arm64: use private ratelimit state along with show_unhandled_signals
arm64: show unhandled SP/PC alignment faults
arm64: vdso: work-around broken ELF toolchains in Makefile
arm64: kernel: rename __cpu_suspend to keep it aligned with arm
arm64: compat: print compat_sp instead of sp
arm64: mm: Fix freeing of the wrong memmap entries with !SPARSEMEM_VMEMMAP
arm64: entry: fix context tracking for el0_sp_pc
arm64: defconfig: enable memtest
arm64: mm: remove reference to tlb.S from comment block
arm64: Do not attempt to use init_mm in reset_context()
arm64: KVM: Switch vgic save/restore to alternative_insn
arm64: alternative: Introduce feature for GICv3 CPU interface
arm64: psci: fix !CONFIG_HOTPLUG_CPU build warning
arm64: fix bug for reloading FPSIMD state after CPU hotplug.
arm64: kernel thread don't need to save fpsimd context.
arm64: fix missing syscall trace exit
arm64: alternative: Work around .inst assembler bugs
arm64: alternative: Merge alternative-asm.h into alternative.h
arm64: alternative: Allow immediate branch as alternative instruction
arm64: Rework alternate sequence for ARM erratum 845719
...
19 Jun, 2015
4 commits
-
Tabs rather than spaces
Signed-off-by: Kevin Mulvey
Signed-off-by: Paolo Bonzini -
fix brace spacing
Signed-off-by: Kevin Mulvey
Signed-off-by: Paolo Bonzini -
The allocation size of the kvm_irq_routing_table depends on
the number of irq routing entries because they are all
allocated with one kzalloc call.When the irq routing table gets bigger this requires high
order allocations which fail from time to time:qemu-kvm: page allocation failure: order:4, mode:0xd0
This patch fixes this issue by breaking up the allocation of
the table and its entries into individual kzalloc calls.
These could all be satisfied with order-0 allocations, which
are less likely to fail.The downside of this change is the lower performance, because
of more calls to kzalloc. But given how often kvm_set_irq_routing
is called in the lifetime of a guest, it doesn't really
matter much.Signed-off-by: Joerg Roedel
[Avoid sparse warning through rcu_access_pointer. - Paolo]
Signed-off-by: Paolo Bonzini -
KVM/ARM changes for v4.2:
- Proper guest time accounting
- FP access fix for 32bit
- The usual pile of GIC fixes
- PSCI fixes
- Random cleanups
18 Jun, 2015
1 commit
-
Back in the days, vgic.c used to have an intimate knowledge of
the actual GICv2. These days, this has been abstracted away into
hardware-specific backends.Remove the now useless arm-gic.h #include directive, making it
clear that GICv2 specific code doesn't belong here.Signed-off-by: Marc Zyngier
17 Jun, 2015
2 commits
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Commit fd1d0ddf2ae9 (KVM: arm/arm64: check IRQ number on userland
injection) rightly limited the range of interrupts userspace can
inject in a guest, but failed to consider the (unlikely) case where
a guest is configured with 1024 interrupts.In this case, interrupts ranging from 1020 to 1023 are unuseable,
as they have a special meaning for the GIC CPU interface.Make sure that these number cannot be used as an IRQ. Also delete
a redundant (and similarily buggy) check in kvm_set_irq.Reported-by: Peter Maydell
Cc: Andre Przywara
Cc: # 4.1, 4.0, 3.19, 3.18
Signed-off-by: Marc Zyngier -
If a GICv3-enabled guest tries to configure Group0, we print a
warning on the console (because we don't support Group0 interrupts).This is fairly pointless, and would allow a guest to spam the
console. Let's just drop the warning.Acked-by: Christoffer Dall
Signed-off-by: Marc Zyngier
12 Jun, 2015
1 commit
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So far, we configured the world-switch by having a small array
of pointers to the save and restore functions, depending on the
GIC used on the platform.Loading these values each time is a bit silly (they never change),
and it makes sense to rely on the instruction patching instead.This leads to a nice cleanup of the code.
Acked-by: Will Deacon
Reviewed-by: Christoffer Dall
Signed-off-by: Marc Zyngier
Signed-off-by: Catalin Marinas