ARM:
- Include icache invalidation optimizations, improving VM startup time
- Support for forwarded level-triggered interrupts, improving
performance for timers and passthrough platform devices
- A small fix for power-management notifiers, and some cosmetic changes
PPC:
- Add MMIO emulation for vector loads and stores
- Allow HPT guests to run on a radix host on POWER9 v2.2 CPUs without
requiring the complex thread synchronization of older CPU versions
- Improve the handling of escalation interrupts with the XIVE interrupt
controller
- Support decrement register migration
- Various cleanups and bugfixes.
s390:
- Cornelia Huck passed maintainership to Janosch Frank
- Exitless interrupts for emulated devices
- Cleanup of cpuflag handling
- kvm_stat counter improvements
- VSIE improvements
- mm cleanup
x86:
- Hypervisor part of SEV
- UMIP, RDPID, and MSR_SMI_COUNT emulation
- Paravirtualized TLB shootdown using the new KVM_VCPU_PREEMPTED bit
- Allow guests to see TOPOEXT, GFNI, VAES, VPCLMULQDQ, and more AVX512
features
- Show vcpu id in its anonymous inode name
- Many fixes and cleanups
- Per-VCPU MSR bitmaps (already merged through x86/pti branch)
- Stable KVM clock when nesting on Hyper-V (merged through x86/hyperv)
-----BEGIN PGP SIGNATURE-----
iQEcBAABCAAGBQJafvMtAAoJEED/6hsPKofo6YcH/Rzf2RmshrWaC3q82yfIV0Qz
Z8N8yJHSaSdc3Jo6cmiVj0zelwAxdQcyjwlT7vxt5SL2yML+/Q0st9Hc3EgGGXPm
Il99eJEl+2MYpZgYZqV8ff3mHS5s5Jms+7BITAeh6Rgt+DyNbykEAvzt+MCHK9cP
xtsIZQlvRF7HIrpOlaRzOPp3sK2/MDZJ1RBE7wYItK3CUAmsHim/LVYKzZkRTij3
/9b4LP1yMMbziG+Yxt1o682EwJB5YIat6fmDG9uFeEVI5rWWN7WFubqs8gCjYy/p
FX+BjpOdgTRnX+1m9GIj0Jlc/HKMXryDfSZS07Zy4FbGEwSiI5SfKECub4mDhuE=
=C/uD
-----END PGP SIGNATURE-----
Merge tag 'kvm-4.16-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM updates from Radim Krčmář:
"ARM:
- icache invalidation optimizations, improving VM startup time
- support for forwarded level-triggered interrupts, improving
performance for timers and passthrough platform devices
- a small fix for power-management notifiers, and some cosmetic
changes
PPC:
- add MMIO emulation for vector loads and stores
- allow HPT guests to run on a radix host on POWER9 v2.2 CPUs without
requiring the complex thread synchronization of older CPU versions
- improve the handling of escalation interrupts with the XIVE
interrupt controller
- support decrement register migration
- various cleanups and bugfixes.
s390:
- Cornelia Huck passed maintainership to Janosch Frank
- exitless interrupts for emulated devices
- cleanup of cpuflag handling
- kvm_stat counter improvements
- VSIE improvements
- mm cleanup
x86:
- hypervisor part of SEV
- UMIP, RDPID, and MSR_SMI_COUNT emulation
- paravirtualized TLB shootdown using the new KVM_VCPU_PREEMPTED bit
- allow guests to see TOPOEXT, GFNI, VAES, VPCLMULQDQ, and more
AVX512 features
- show vcpu id in its anonymous inode name
- many fixes and cleanups
- per-VCPU MSR bitmaps (already merged through x86/pti branch)
- stable KVM clock when nesting on Hyper-V (merged through
x86/hyperv)"
* tag 'kvm-4.16-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (197 commits)
KVM: PPC: Book3S: Add MMIO emulation for VMX instructions
KVM: PPC: Book3S HV: Branch inside feature section
KVM: PPC: Book3S HV: Make HPT resizing work on POWER9
KVM: PPC: Book3S HV: Fix handling of secondary HPTEG in HPT resizing code
KVM: PPC: Book3S PR: Fix broken select due to misspelling
KVM: x86: don't forget vcpu_put() in kvm_arch_vcpu_ioctl_set_sregs()
KVM: PPC: Book3S PR: Fix svcpu copying with preemption enabled
KVM: PPC: Book3S HV: Drop locks before reading guest memory
kvm: x86: remove efer_reload entry in kvm_vcpu_stat
KVM: x86: AMD Processor Topology Information
x86/kvm/vmx: do not use vm-exit instruction length for fast MMIO when running nested
kvm: embed vcpu id to dentry of vcpu anon inode
kvm: Map PFN-type memory regions as writable (if possible)
x86/kvm: Make it compile on 32bit and with HYPYERVISOR_GUEST=n
KVM: arm/arm64: Fixup userspace irqchip static key optimization
KVM: arm/arm64: Fix userspace_irqchip_in_use counting
KVM: arm/arm64: Fix incorrect timer_is_pending logic
MAINTAINERS: update KVM/s390 maintainers
MAINTAINERS: add Halil as additional vfio-ccw maintainer
MAINTAINERS: add David as a reviewer for KVM/s390
...
Now that we have per-CPU vectors, let's plug then in the KVM/arm64 code.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
The vcpu parameter isn't used for anything, and gets in the way of
further cleanups. Let's get rid of it.
Acked-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>
So far, we loose the Exec property whenever we take permission
faults, as we always reconstruct the PTE/PMD from scratch. This
can be counter productive as we can end-up with the following
fault sequence:
X -> RO -> ROX -> RW -> RWX
Instead, we can lookup the existing PTE/PMD and clear the XN bit in the
new entry if it was already cleared in the old one, leadig to a much
nicer fault sequence:
X -> ROX -> RWX
Reviewed-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>
We've so far eagerly invalidated the icache, no matter how
the page was faulted in (data or prefetch abort).
But we can easily track execution by setting the XN bits
in the S2 page tables, get the prefetch abort at HYP and
perform the icache invalidation at that time only.
As for most VMs, the instruction working set is pretty
small compared to the data set, this is likely to save
some traffic (specially as the invalidation is broadcast).
Reviewed-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>
Calling __cpuc_coherent_user_range to invalidate the icache on
a PIPT icache machine has some pointless overhead, as it starts
by cleaning the dcache to the PoU, while we're guaranteed to
have already cleaned it to the PoC.
As KVM is the only user of such a feature, let's implement some
ad-hoc cache flushing in kvm_mmu.h. Should it become useful to
other subsystems, it can be moved to a more global location.
Reviewed-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>
As we're about to introduce opportunistic invalidation of the icache,
let's split dcache and icache flushing.
Acked-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Currently, when using VA_BITS < 48, if the ID map text happens to be
placed in physical memory above VA_BITS, we increase the VA size (up to
48) and create a new table level, in order to map in the ID map text.
This is okay because the system always supports 48 bits of VA.
This patch extends the code such that if the system supports 52 bits of
VA, and the ID map text is placed that high up, then we increase the VA
size accordingly, up to 52.
One difference from the current implementation is that so far the
condition of VA_BITS < 48 has meant that the top level table is always
"full", with the maximum number of entries, and an extra table level is
always needed. Now, when VA_BITS = 48 (and using 64k pages), the top
level table is not full, and we simply need to increase the number of
entries in it, instead of creating a new table level.
Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Bob Picco <bob.picco@oracle.com>
Reviewed-by: Bob Picco <bob.picco@oracle.com>
Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
[catalin.marinas@arm.com: reduce arguments to __create_hyp_mappings()]
[catalin.marinas@arm.com: reworked/renamed __cpu_uses_extended_idmap_level()]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
The top 4 bits of a 52-bit physical address are positioned at bits 2..5
in the TTBR registers. Introduce a couple of macros to move the bits
there, and change all TTBR writers to use them.
Leave TTBR0 PAN code unchanged, to avoid complicating it. A system with
52-bit PA will have PAN anyway (because it's ARMv8.1 or later), and a
system without 52-bit PA can only use up to 48-bit PAs. A later patch in
this series will add a kconfig dependency to ensure PAN is configured.
In addition, when using 52-bit PA there is a special alignment
requirement on the top-level table. We don't currently have any VA_BITS
configuration that would violate the requirement, but one could be added
in the future, so add a compile-time BUG_ON to check for it.
Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Bob Picco <bob.picco@oracle.com>
Reviewed-by: Bob Picco <bob.picco@oracle.com>
Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
[catalin.marinas@arm.com: added TTBR_BADD_MASK_52 comment]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
With __cpu_reset_hyp_mode having become fairly dumb, there is no
need for kvm_get_idmap_start anymore.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
Now that we unconditionally flush newly mapped pages to the PoC,
there is no need to care about the "uncached" status of individual
pages - they must all be visible all the way down.
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
When we fault in a page, we flush it to the PoC (Point of Coherency)
if the faulting vcpu has its own caches off, so that it can observe
the page we just brought it.
But if the vcpu has its caches on, we skip that step. Bad things
happen when *another* vcpu tries to access that page with its own
caches disabled. At that point, there is no garantee that the
data has made it to the PoC, and we access stale data.
The obvious fix is to always flush to PoC when a page is faulted
in, no matter what the state of the vcpu is.
Cc: stable@vger.kernel.org
Fixes: 2d58b733c8 ("arm64: KVM: force cache clean on page fault when caches are off")
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
When modifying Stage-2 page tables, we perform cache maintenance to
account for non-coherent page table walks. However, this is unnecessary,
as page table walks are guaranteed to be coherent in the presence of the
virtualization extensions.
Per ARM DDI 0406C.c, section B1.7 ("The Virtualization Extensions"), the
virtualization extensions mandate the multiprocessing extensions.
Per ARM DDI 0406C.c, section B3.10.1 ("General TLB maintenance
requirements"), as described in the sub-section titled "TLB maintenance
operations and the memory order model", this maintenance is not required
in the presence of the multiprocessing extensions.
Hence, we need not perform this cache maintenance when modifying Stage-2
entries.
This patch removes the logic for performing the redundant maintenance.
To ensure visibility and ordering of updates, a dsb(ishst) that was
otherwise implicit in the maintenance is folded into kvm_set_pmd() and
kvm_set_pte().
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Christoffer Dall <christoffer.dall@linaro.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: kvmarm@lists.cs.columbia.edu
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
We have both KERN_TO_HYP and kern_hyp_va, which do the exact same
thing. Let's standardize on the latter.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
We can now remove a number of dead #defines, thanks to the trampoline
code being gone.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
There is no way to free the boot PGD, because it doesn't exist
anymore as a standalone entity.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Since we now only have one set of page tables, the concept of
boot_pgd is useless and can be removed. We still keep it as
an element of the "extended idmap" thing.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Currently, create_hyp_mappings applies a "one size fits all" page
protection (PAGE_HYP). As we're heading towards separate protections
for different sections, let's make this protection a parameter, and
let the callers pass their prefered protection (PAGE_HYP for everyone
for the time being).
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
- x86: miscellaneous fixes, AVIC support (local APIC virtualization,
AMD version)
- s390: polling for interrupts after a VCPU goes to halted state is
now enabled for s390; use hardware provided information about facility
bits that do not need any hypervisor activity, and other fixes for
cpu models and facilities; improve perf output; floating interrupt
controller improvements.
- MIPS: miscellaneous fixes
- PPC: bugfixes only
- ARM: 16K page size support, generic firmware probing layer for
timer and GIC
Christoffer Dall (KVM-ARM maintainer) says:
"There are a few changes in this pull request touching things outside
KVM, but they should all carry the necessary acks and it made the
merge process much easier to do it this way."
though actually the irqchip maintainers' acks didn't make it into the
patches. Marc Zyngier, who is both irqchip and KVM-ARM maintainer,
later acked at http://mid.gmane.org/573351D1.4060303@arm.com
"more formally and for documentation purposes".
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.22 (GNU/Linux)
iQEcBAABAgAGBQJXPJjyAAoJEL/70l94x66DhioH/j4fwQ0FmfPSM9PArzaFHQdx
LNE3tU4+bobbsy1BJr4DiAaOUQn3DAgwUvGLWXdeLiOXtoWXBiFHKaxlqEsCA6iQ
xcTH1TgfxsVoqGQ6bT9X/2GCx70heYpcWG3f+zqBy7ZfFmQykLAC/HwOr52VQL8f
hUFi3YmTHcnorp0n5Xg+9r3+RBS4D/kTbtdn6+KCLnPJ0RcgNkI3/NcafTemoofw
Tkv8+YYFNvKV13qlIfVqxMa0GwWI3pP6YaNKhaS5XO8Pu16HuuF1JthJsUBDzwBa
RInp8R9MoXgsBYhLpz3jc9vWG7G9yDl5LehsD9KOUGOaFYJ7sQN+QZOusa6jFgA=
=llO5
-----END PGP SIGNATURE-----
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM updates from Paolo Bonzini:
"Small release overall.
x86:
- miscellaneous fixes
- AVIC support (local APIC virtualization, AMD version)
s390:
- polling for interrupts after a VCPU goes to halted state is now
enabled for s390
- use hardware provided information about facility bits that do not
need any hypervisor activity, and other fixes for cpu models and
facilities
- improve perf output
- floating interrupt controller improvements.
MIPS:
- miscellaneous fixes
PPC:
- bugfixes only
ARM:
- 16K page size support
- generic firmware probing layer for timer and GIC
Christoffer Dall (KVM-ARM maintainer) says:
"There are a few changes in this pull request touching things
outside KVM, but they should all carry the necessary acks and it
made the merge process much easier to do it this way."
though actually the irqchip maintainers' acks didn't make it into the
patches. Marc Zyngier, who is both irqchip and KVM-ARM maintainer,
later acked at http://mid.gmane.org/573351D1.4060303@arm.com ('more
formally and for documentation purposes')"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (82 commits)
KVM: MTRR: remove MSR 0x2f8
KVM: x86: make hwapic_isr_update and hwapic_irr_update look the same
svm: Manage vcpu load/unload when enable AVIC
svm: Do not intercept CR8 when enable AVIC
svm: Do not expose x2APIC when enable AVIC
KVM: x86: Introducing kvm_x86_ops.apicv_post_state_restore
svm: Add VMEXIT handlers for AVIC
svm: Add interrupt injection via AVIC
KVM: x86: Detect and Initialize AVIC support
svm: Introduce new AVIC VMCB registers
KVM: split kvm_vcpu_wake_up from kvm_vcpu_kick
KVM: x86: Introducing kvm_x86_ops VCPU blocking/unblocking hooks
KVM: x86: Introducing kvm_x86_ops VM init/destroy hooks
KVM: x86: Rename kvm_apic_get_reg to kvm_lapic_get_reg
KVM: x86: Misc LAPIC changes to expose helper functions
KVM: shrink halt polling even more for invalid wakeups
KVM: s390: set halt polling to 80 microseconds
KVM: halt_polling: provide a way to qualify wakeups during poll
KVM: PPC: Book3S HV: Re-enable XICS fast path for irqfd-generated interrupts
kvm: Conditionally register IRQ bypass consumer
...
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>
The current kvm implementation on arm64 does cpu-specific initialization
at system boot, and has no way to gracefully shutdown a core in terms of
kvm. This prevents kexec from rebooting the system at EL2.
This patch adds a cpu tear-down function and also puts an existing cpu-init
code into a separate function, kvm_arch_hardware_disable() and
kvm_arch_hardware_enable() respectively.
We don't need the arm64 specific cpu hotplug hook any more.
Since this patch modifies common code between arm and arm64, one stub
definition, __cpu_reset_hyp_mode(), is added on arm side to avoid
compilation errors.
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
[Rebase, added separate VHE init/exit path, changed resets use of
kvm_call_hyp() to the __version, en/disabled hardware in init_subsystems(),
added icache maintenance to __kvm_hyp_reset() and removed lr restore, removed
guest-enter after teardown handling]
Signed-off-by: James Morse <james.morse@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@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>
Now that we have switched to explicit page table routines,
get rid of the obsolete kvm_* wrappers.
Also, kvm_tlb_flush_vmid_by_ipa is now called only on stage2
page tables, hence get rid of the redundant check.
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>
Introduce hyp_pxx_table_empty helpers for checking whether
a given table entry is empty. This will be used explicitly
once we switch to explicit routines for hyp page table walk.
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Define the page table helpers for walking the stage2 pagetable
for arm. Since both hyp and stage2 have the same number of levels,
as that of the host we reuse the host helpers.
The exceptions are the p.d_addr_end routines which have to deal
with IPA > 32bit, hence we use the open coded version of their host helpers
which supports 64bit.
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Rearrange the code for fake pgd handling, which is applicable
only for arm64. This will later be removed once we introduce
the stage2 page table walker macros.
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Continuing our rework of the CPU context, we now move the CP15
array into the CPU context structure. As this causes quite a bit
of churn, we introduce the vcpu_cp15() macro that abstract the
location of the actual array. This will probably help next time
we have to revisit that code.
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
To date, we have implemented two I/O usage models for persistent memory,
PMEM (a persistent "ram disk") and DAX (mmap persistent memory into
userspace). This series adds a third, DAX-GUP, that allows DAX mappings
to be the target of direct-i/o. It allows userspace to coordinate
DMA/RDMA from/to persistent memory.
The implementation leverages the ZONE_DEVICE mm-zone that went into
4.3-rc1 (also discussed at kernel summit) to flag pages that are owned
and dynamically mapped by a device driver. The pmem driver, after
mapping a persistent memory range into the system memmap via
devm_memremap_pages(), arranges for DAX to distinguish pfn-only versus
page-backed pmem-pfns via flags in the new pfn_t type.
The DAX code, upon seeing a PFN_DEV+PFN_MAP flagged pfn, flags the
resulting pte(s) inserted into the process page tables with a new
_PAGE_DEVMAP flag. Later, when get_user_pages() is walking ptes it keys
off _PAGE_DEVMAP to pin the device hosting the page range active.
Finally, get_page() and put_page() are modified to take references
against the device driver established page mapping.
Finally, this need for "struct page" for persistent memory requires
memory capacity to store the memmap array. Given the memmap array for a
large pool of persistent may exhaust available DRAM introduce a
mechanism to allocate the memmap from persistent memory. The new
"struct vmem_altmap *" parameter to devm_memremap_pages() enables
arch_add_memory() to use reserved pmem capacity rather than the page
allocator.
This patch (of 18):
The core has developed a need for a "pfn_t" type [1]. Move the existing
pfn_t in KVM to kvm_pfn_t [2].
[1]: https://lists.01.org/pipermail/linux-nvdimm/2015-September/002199.html
[2]: https://lists.01.org/pipermail/linux-nvdimm/2015-September/002218.html
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The ARMv8.1 architecture extension allows to choose between 8-bit and
16-bit of VMID, so use this capability for KVM.
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
The main change here is a significant head.S rework that allows us to
boot on machines with physical memory at a really high address without
having to increase our mapped VA range. Other changes include:
- AES performance boost for Cortex-A57
- AArch32 (compat) userspace with 64k pages
- Cortex-A53 erratum workaround for #845719
- defconfig updates (new platforms, PCI, ...)
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1
iQEcBAABCgAGBQJVLnQpAAoJELescNyEwWM03RIH/iwcDc0MBZgkwfD5cnY+29p4
m89lMDo3SyGQT4NynHSw7P3R7c3zULmI+9hmJMw/yfjjjL6m7X+vVAF3xj1Am4Al
OzCqYLHyFnlRktzJ6dWeF1Ese7tWqPpxn+OCXgYNpz/r5MfF/HhlyX/qNzAQPKrw
ZpDvnt44DgUfweqjTbwQUg2wkyCRjmz57MQYxDcmJStdpHIu24jWOvDIo3OJGjyS
L49I9DU6DGUhkISZmmBE0T7vmKMD1BcgI7OIzX2WIqn521QT+GSLMhRxaHmK1s1V
A8gaMTwpo0xFhTAt7sbw/5+2663WmfRdZI+FtduvORsoxX6KdDn7DH1NQixIm8s=
=+F0I
-----END PGP SIGNATURE-----
Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Will Deacon:
"Here are the core arm64 updates for 4.1.
Highlights include a significant rework to head.S (allowing us to boot
on machines with physical memory at a really high address), an AES
performance boost on Cortex-A57 and the ability to run a 32-bit
userspace with 64k pages (although this requires said userspace to be
built with a recent binutils).
The head.S rework spilt over into KVM, so there are some changes under
arch/arm/ which have been acked by Marc Zyngier (KVM co-maintainer).
In particular, the linker script changes caused us some issues in
-next, so there are a few merge commits where we had to apply fixes on
top of a stable branch.
Other changes include:
- AES performance boost for Cortex-A57
- AArch32 (compat) userspace with 64k pages
- Cortex-A53 erratum workaround for #845719
- defconfig updates (new platforms, PCI, ...)"
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (39 commits)
arm64: fix midr range for Cortex-A57 erratum 832075
arm64: errata: add workaround for cortex-a53 erratum #845719
arm64: Use bool function return values of true/false not 1/0
arm64: defconfig: updates for 4.1
arm64: Extract feature parsing code from cpu_errata.c
arm64: alternative: Allow immediate branch as alternative instruction
arm64: insn: Add aarch64_insn_decode_immediate
ARM: kvm: round HYP section to page size instead of log2 upper bound
ARM: kvm: assert on HYP section boundaries not actual code size
arm64: head.S: ensure idmap_t0sz is visible
arm64: pmu: add support for interrupt-affinity property
dt: pmu: extend ARM PMU binding to allow for explicit interrupt affinity
arm64: head.S: ensure visibility of page tables
arm64: KVM: use ID map with increased VA range if required
arm64: mm: increase VA range of identity map
ARM: kvm: implement replacement for ld's LOG2CEIL()
arm64: proc: remove unused cpu_get_pgd macro
arm64: enforce x1|x2|x3 == 0 upon kernel entry as per boot protocol
arm64: remove __calc_phys_offset
arm64: merge __enable_mmu and __turn_mmu_on
...
This patch modifies the HYP init code so it can deal with system
RAM residing at an offset which exceeds the reach of VA_BITS.
Like for EL1, this involves configuring an additional level of
translation for the ID map. However, in case of EL2, this implies
that all translations use the extra level, as we cannot seamlessly
switch between translation tables with different numbers of
translation levels.
So add an extra translation table at the root level. Since the
ID map and the runtime HYP map are guaranteed not to overlap, they
can share this root level, and we can essentially merge these two
tables into one.
Tested-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
The kernel's pgd_index macro is designed to index a normal, page
sized array. KVM is a bit diffferent, as we can use concatenated
pages to have a bigger address space (for example 40bit IPA with
4kB pages gives us an 8kB PGD.
In the above case, the use of pgd_index will always return an index
inside the first 4kB, which makes a guest that has memory above
0x8000000000 rather unhappy, as it spins forever in a page fault,
whist the host happilly corrupts the lower pgd.
The obvious fix is to get our own kvm_pgd_index that does the right
thing(tm).
Tested on X-Gene with a hacked kvmtool that put memory at a stupidly
high address.
Reviewed-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>
We're using __get_free_pages with to allocate the guest's stage-2
PGD. The standard behaviour of this function is to return a set of
pages where only the head page has a valid refcount.
This behaviour gets us into trouble when we're trying to increment
the refcount on a non-head page:
page:ffff7c00cfb693c0 count:0 mapcount:0 mapping: (null) index:0x0
flags: 0x4000000000000000()
page dumped because: VM_BUG_ON_PAGE((*({ __attribute__((unused)) typeof((&page->_count)->counter) __var = ( typeof((&page->_count)->counter)) 0; (volatile typeof((&page->_count)->counter) *)&((&page->_count)->counter); })) <= 0)
BUG: failure at include/linux/mm.h:548/get_page()!
Kernel panic - not syncing: BUG!
CPU: 1 PID: 1695 Comm: kvm-vcpu-0 Not tainted 4.0.0-rc1+ #3825
Hardware name: APM X-Gene Mustang board (DT)
Call trace:
[<ffff80000008a09c>] dump_backtrace+0x0/0x13c
[<ffff80000008a1e8>] show_stack+0x10/0x1c
[<ffff800000691da8>] dump_stack+0x74/0x94
[<ffff800000690d78>] panic+0x100/0x240
[<ffff8000000a0bc4>] stage2_get_pmd+0x17c/0x2bc
[<ffff8000000a1dc4>] kvm_handle_guest_abort+0x4b4/0x6b0
[<ffff8000000a420c>] handle_exit+0x58/0x180
[<ffff80000009e7a4>] kvm_arch_vcpu_ioctl_run+0x114/0x45c
[<ffff800000099df4>] kvm_vcpu_ioctl+0x2e0/0x754
[<ffff8000001c0a18>] do_vfs_ioctl+0x424/0x5c8
[<ffff8000001c0bfc>] SyS_ioctl+0x40/0x78
CPU0: stopping
A possible approach for this is to split the compound page using
split_page() at allocation time, and change the teardown path to
free one page at a time. It turns out that alloc_pages_exact() and
free_pages_exact() does exactly that.
While we're at it, the PGD allocation code is reworked to reduce
duplication.
This has been tested on an X-Gene platform with a 4kB/48bit-VA host
kernel, and kvmtool hacked to place memory in the second page of
the hardware PGD (PUD for the host kernel). Also regression-tested
on a Cubietruck (Cortex-A7).
[ Reworked to use alloc_pages_exact() and free_pages_exact() and to
return pointers directly instead of by reference as arguments
- Christoffer ]
Reported-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
The check is supposed to catch page-unaligned sizes, not the inverse.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
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.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.22 (GNU/Linux)
iQEcBAABAgAGBQJU28rkAAoJEL/70l94x66DXqQH/1TDOfJIjW7P2kb0Sw7Fy1wi
cEX1KO/VFxAqc8R0E/0Wb55CXyPjQJM6xBXuFr5cUDaIjQ8ULSktL4pEwXyyv/s5
DBDkN65mriry2w5VuEaRLVcuX9Wy+tqLQXWNkEySfyb4uhZChWWHvKEcgw5SqCyg
NlpeHurYESIoNyov3jWqvBjr4OmaQENyv7t2c6q5ErIgG02V+iCux5QGbphM2IC9
LFtPKxoqhfeB2xFxTOIt8HJiXrZNwflsTejIlCl/NSEiDVLLxxHCxK2tWK/tUXMn
JfLD9ytXBWtNMwInvtFm4fPmDouv2VDyR0xnK2db+/axsJZnbxqjGu1um4Dqbak=
=7gdx
-----END PGP SIGNATURE-----
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
...
When handling a fault in stage-2, we need to resync I$ and D$, just
to be sure we don't leave any old cache line behind.
That's very good, except that we do so using the *user* address.
Under heavy load (swapping like crazy), we may end up in a situation
where the page gets mapped in stage-2 while being unmapped from
userspace by another CPU.
At that point, the DC/IC instructions can generate a fault, which
we handle with kvm->mmu_lock held. The box quickly deadlocks, user
is unhappy.
Instead, perform this invalidation through the kernel mapping,
which is guaranteed to be present. The box is much happier, and so
am I.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Let's assume a guest has created an uncached mapping, and written
to that page. Let's also assume that the host uses a cache-coherent
IO subsystem. Let's finally assume that the host is under memory
pressure and starts to swap things out.
Before this "uncached" page is evicted, we need to make sure
we invalidate potential speculated, clean cache lines that are
sitting there, or the IO subsystem is going to swap out the
cached view, loosing the data that has been written directly
into memory.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Trying to emulate the behaviour of set/way cache ops is fairly
pointless, as there are too many ways we can end-up missing stuff.
Also, there is some system caches out there that simply ignore
set/way operations.
So instead of trying to implement them, let's convert it to VA ops,
and use them as a way to re-enable the trapping of VM ops. That way,
we can detect the point when the MMU/caches are turned off, and do
a full VM flush (which is what the guest was trying to do anyway).
This allows a 32bit zImage to boot on the APM thingy, and will
probably help bootloaders in general.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Add support for initial write protection of VM memslots. This patch
series assumes that huge PUDs will not be used in 2nd stage tables, which is
always valid on ARMv7
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Mario Smarduch <m.smarduch@samsung.com>
Introduce a new function to unmap user RAM regions in the stage2 page
tables. This is needed on reboot (or when the guest turns off the MMU)
to ensure we fault in pages again and make the dcache, RAM, and icache
coherent.
Using unmap_stage2_range for the whole guest physical range does not
work, because that unmaps IO regions (such as the GIC) which will not be
recreated or in the best case faulted in on a page-by-page basis.
Call this function on secondary and subsequent calls to the
KVM_ARM_VCPU_INIT ioctl so that a reset VCPU will detect the guest
Stage-1 MMU is off when faulting in pages and make the caches coherent.
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
To allow handling of incoherent memslots in a subsequent patch, this
patch adds a paramater 'ipa_uncached' to cache_coherent_guest_page()
so that we can instruct it to flush the page's contents to DRAM even
if the guest has caching globally enabled.
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
This patch adds the necessary support for all host kernel PGSIZE and
VA_SPACE configuration options for both EL2 and the Stage-2 page tables.
However, for 40bit and 42bit PARange systems, the architecture mandates
that VTCR_EL2.SL0 is maximum 1, resulting in fewer levels of stage-2
pagge tables than levels of host kernel page tables. At the same time,
systems with a PARange > 42bit, we limit the IPA range by always setting
VTCR_EL2.T0SZ to 24.
To solve the situation with different levels of page tables for Stage-2
translation than the host kernel page tables, we allocate a dummy PGD
with pointers to our actual inital level Stage-2 page table, in order
for us to reuse the kernel pgtable manipulation primitives. Reproducing
all these in KVM does not look pretty and unnecessarily complicates the
32-bit side.
Systems with a PARange < 40bits are not yet supported.
[ I have reworked this patch from its original form submitted by
Jungseok to take the architecture constraints into consideration.
There were too many changes from the original patch for me to
preserve the authorship. Thanks to Catalin Marinas for his help in
figuring out a good solution to this challenge. I have also fixed
various bugs and missing error code handling from the original
patch. - Christoffer ]
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Jungseok Lee <jungseoklee85@gmail.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Add support for read-only MMIO passthrough mappings by adding a
'writable' parameter to kvm_phys_addr_ioremap. For the moment,
mappings will be read-write even if 'writable' is false, but once
the definition of PAGE_S2_DEVICE gets changed, those mappings will
be created read-only.
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
The ISS encoding for an exception from a Data Abort has a WnR
bit[6] that indicates whether the Data Abort was caused by a
read or a write instruction. While there are several fields
in the encoding that are only valid if the ISV bit[24] is set,
WnR is not one of them, so we can read it unconditionally.
Instead of fixing both implementations of kvm_is_write_fault()
in place, reimplement it just once using kvm_vcpu_dabt_iswrite(),
which already does the right thing with respect to the WnR bit.
Also fix up the callers to pass 'vcpu'
Acked-by: Laszlo Ersek <lersek@redhat.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
unmap_range() was utterly broken, to quote Marc, and broke in all sorts
of situations. It was also quite complicated to follow and didn't
follow the usual scheme of having a separate iterating function for each
level of page tables.
Address this by refactoring the code and introduce a pgd_clear()
function.
Reviewed-by: Jungseok Lee <jays.lee@samsung.com>
Reviewed-by: Mario Smarduch <m.smarduch@samsung.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
In order for a guest with caches disabled to observe data written
contained in a given page, we need to make sure that page is
committed to memory, and not just hanging in the cache (as guest
accesses are completely bypassing the cache until it decides to
enable it).
For this purpose, hook into the coherent_cache_guest_page
function and flush the region if the guest SCTLR
register doesn't show the MMU and caches as being enabled.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
When the guest runs with caches disabled (like in an early boot
sequence, for example), all the writes are diectly going to RAM,
bypassing the caches altogether.
Once the MMU and caches are enabled, whatever sits in the cache
becomes suddenly visible, which isn't what the guest expects.
A way to avoid this potential disaster is to invalidate the cache
when the MMU is being turned on. For this, we hook into the SCTLR_EL1
trapping code, and scan the stage-2 page tables, invalidating the
pages/sections that have already been mapped in.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
The use of p*d_addr_end with stage-2 translation is slightly dodgy,
as the IPA is 40bits, while all the p*d_addr_end helpers are
taking an unsigned long (arm64 is fine with that as unligned long
is 64bit).
The fix is to introduce 64bit clean versions of the same helpers,
and use them in the stage-2 page table code.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
In order for the guest with caches off to observe data written
contained in a given page, we need to make sure that page is
committed to memory, and not just hanging in the cache (as
guest accesses are completely bypassing the cache until it
decides to enable it).
For this purpose, hook into the coherent_icache_guest_page
function and flush the region if the guest SCTLR_EL1
register doesn't show the MMU and caches as being enabled.
The function also get renamed to coherent_cache_guest_page.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
KVM initialisation fails on architectures implementing virt_to_idmap()
because virt_to_phys() on such architectures won't fetch you the correct
idmap page.
So update the KVM ARM code to use the virt_to_idmap() to fix the issue.
Since the KVM code is shared between arm and arm64, we create
kvm_virt_to_phys() and handle the redirection in respective headers.
Cc: Christoffer Dall <christoffer.dall@linaro.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Linus Torvalds