If a vcpu exits due to request a user mode spinlock, then
the spinlock-holder may be preempted in user mode or kernel mode.
(Note that not all architectures trap spin loops in user mode,
only AMD x86 and ARM/ARM64 currently do).
But if a vcpu exits in kernel mode, then the holder must be
preempted in kernel mode, so we should choose a vcpu in kernel mode
as a more likely candidate for the lock holder.
This introduces kvm_arch_vcpu_in_kernel() to decide whether the
vcpu is in kernel-mode when it's preempted. kvm_vcpu_on_spin's
new argument says the same of the spinning VCPU.
Signed-off-by: Longpeng(Mike) <longpeng2@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
nested_get_page() just sounds confusing. All we want is a page from G1.
This is even unrelated to nested.
Let's introduce kvm_vcpu_gpa_to_page() so we don't get too lengthy
lines.
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
[Squash pasto fix from Wanpeng Li. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
During teardown, accesses to memslots and buses are using
rcu_dereference_protected with an always-true condition because
these accesses are done outside the usual mutexes. This
is because the last reference is gone and there cannot be any
concurrent modifications, but rcu_dereference_protected is
ugly and unobvious.
Instead, check the refcount in kvm_get_bus and __kvm_memslots.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Simplify and improve the code so that the PID is always available in
the uevent even when debugfs is not available.
This adds a userspace_pid field to struct kvm, as per Radim's
suggestion, so that the PID can be retrieved on destruction too.
Acked-by: Janosch Frank <frankja@linux.vnet.ibm.com>
Fixes: 286de8f6ac ("KVM: trigger uevents when creating or destroying a VM")
Signed-off-by: Claudio Imbrenda <imbrenda@linux.vnet.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
kvm memslots are protected by srcu and not by rcu. We must use
srcu_dereference_check instead of rcu_dereference_check.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
we access the memslots array via srcu. Mark it as such and
use the right access functions also for the freeing of
memory slots.
Found by sparse:
./include/linux/kvm_host.h:565:16: error: incompatible types in
comparison expression (different address spaces)
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
mark kvm->busses as rcu protected and use the correct access
function everywhere.
found by sparse
virt/kvm/kvm_main.c:3490:15: error: incompatible types in comparison expression (different address spaces)
virt/kvm/kvm_main.c:3509:15: error: incompatible types in comparison expression (different address spaces)
virt/kvm/kvm_main.c:3561:15: error: incompatible types in comparison expression (different address spaces)
virt/kvm/kvm_main.c:3644:15: error: incompatible types in comparison expression (different address spaces)
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
We do use rcu to protect the pid pointer. Mark it as such and
adopt all code to use the proper access methods.
This was detected by sparse.
"virt/kvm/kvm_main.c:2248:15: error: incompatible types in comparison
expression (different address spaces)"
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
A first step in vcpu->requests encapsulation. Additionally, we now
use READ_ONCE() when accessing vcpu->requests, which ensures we
always load vcpu->requests when it's accessed. This is important as
other threads can change it any time. Also, READ_ONCE() documents
that vcpu->requests is used with other threads, likely requiring
memory barriers, which it does.
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
[ Documented the new use of READ_ONCE() and converted another check
in arch/mips/kvm/vz.c ]
Signed-off-by: Andrew Jones <drjones@redhat.com>
Acked-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
Marc Zyngier suggested that we define the arch specific VCPU request
base, rather than requiring each arch to remember to start from 8.
That suggestion, along with Radim Krcmar's recent VCPU request flag
addition, snowballed into defining something of an arch VCPU request
defining API.
No functional change.
(Looks like x86 is running out of arch VCPU request bits. Maybe
someday we'll need to extend to 64.)
Signed-off-by: Andrew Jones <drjones@redhat.com>
Acked-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
* ARM: bugfixes; moved shared 32-bit/64-bit files to virt/kvm/arm;
support for saving/restoring virtual ITS state to userspace
* PPC: XIVE (eXternal Interrupt Virtualization Engine) support
* x86: nVMX improvements, including emulated page modification logging
(PML) which brings nice performance improvements on some workloads
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.22 (GNU/Linux)
iQEcBAABAgAGBQJZEeusAAoJEL/70l94x66Dq+cH/RkL9znP717k7Z0jS8/FJN9q
wKU8j0jRxuqjnvEu89redfFKxElWM9T1fwReBObjWct9+hyJ9Pbpf95Lr9ca39PR
zhiBMKl79he0gHV/z48ItuzH1mOrU/KzFfxHYLlBd4oGw0ZdUttWAsUtaWQ8UNFo
xtyu2R+CWYLeAUBrpYmkvrOjhnB+S9+f4y2OY9pXsMg4HN9/Tdn0B656yTOWdu9C
onO3QQXNY/dzGFLH3tA/kAbz25x4Y+pP2UHlMm5vkW8XWPn+lluUwtBonTKdzy64
RDWWUWcs0k37ps4H9b56oXmz8ZFZ0FQF3MimDQueGHSYOXCxU5EqmC9c7KZmZrg=
=KcCv
-----END PGP SIGNATURE-----
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull more KVM updates from Paolo Bonzini:
"ARM:
- bugfixes
- moved shared 32-bit/64-bit files to virt/kvm/arm
- support for saving/restoring virtual ITS state to userspace
PPC:
- XIVE (eXternal Interrupt Virtualization Engine) support
x86:
- nVMX improvements, including emulated page modification logging
(PML) which brings nice performance improvements on some workloads"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (45 commits)
KVM: arm/arm64: vgic-its: Cleanup after failed ITT restore
KVM: arm/arm64: Don't call map_resources when restoring ITS tables
KVM: arm/arm64: Register ITS iodev when setting base address
KVM: arm/arm64: Get rid of its->initialized field
KVM: arm/arm64: Register iodevs when setting redist base and creating VCPUs
KVM: arm/arm64: Slightly rework kvm_vgic_addr
KVM: arm/arm64: Make vgic_v3_check_base more broadly usable
KVM: arm/arm64: Refactor vgic_register_redist_iodevs
KVM: Add kvm_vcpu_get_idx to get vcpu index in kvm->vcpus
nVMX: Advertise PML to L1 hypervisor
nVMX: Implement emulated Page Modification Logging
kvm: x86: Add a hook for arch specific dirty logging emulation
kvm: nVMX: Validate CR3 target count on nested VM-entry
KVM: set no_llseek in stat_fops_per_vm
KVM: arm/arm64: vgic: Rename kvm_vgic_vcpu_init to kvm_vgic_vcpu_enable
KVM: arm/arm64: Clarification and relaxation to ITS save/restore ABI
KVM: arm64: vgic-v3: KVM_DEV_ARM_VGIC_SAVE_PENDING_TABLES
KVM: arm64: vgic-its: Fix pending table sync
KVM: arm64: vgic-its: ITT save and restore
KVM: arm64: vgic-its: Device table save/restore
...
Pull RCU updates from Ingo Molnar:
"The main changes are:
- Debloat RCU headers
- Parallelize SRCU callback handling (plus overlapping patches)
- Improve the performance of Tree SRCU on a CPU-hotplug stress test
- Documentation updates
- Miscellaneous fixes"
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (74 commits)
rcu: Open-code the rcu_cblist_n_lazy_cbs() function
rcu: Open-code the rcu_cblist_n_cbs() function
rcu: Open-code the rcu_cblist_empty() function
rcu: Separately compile large rcu_segcblist functions
srcu: Debloat the <linux/rcu_segcblist.h> header
srcu: Adjust default auto-expediting holdoff
srcu: Specify auto-expedite holdoff time
srcu: Expedite first synchronize_srcu() when idle
srcu: Expedited grace periods with reduced memory contention
srcu: Make rcutorture writer stalls print SRCU GP state
srcu: Exact tracking of srcu_data structures containing callbacks
srcu: Make SRCU be built by default
srcu: Fix Kconfig botch when SRCU not selected
rcu: Make non-preemptive schedule be Tasks RCU quiescent state
srcu: Expedite srcu_schedule_cbs_snp() callback invocation
srcu: Parallelize callback handling
kvm: Move srcu_struct fields to end of struct kvm
rcu: Fix typo in PER_RCU_NODE_PERIOD header comment
rcu: Use true/false in assignment to bool
rcu: Use bool value directly
...
Changes include:
- A fix related to the 32-bit idmap stub
- A fix to the bitmask used to deode the operands of an AArch32 CP
instruction
- We have moved the files shared between arch/arm/kvm and
arch/arm64/kvm to virt/kvm/arm
- We add support for saving/restoring the virtual ITS state to
userspace
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1
iQEcBAABAgAGBQJZEZihAAoJEEtpOizt6ddyGDYH/jmGjDMnryORn2P2o10dUQKJ
RnHTQYnpOYqnprlkFtZFpmK+mjl/a8R1Btb7GK2EwmovTR95pMYPRqtrCTOL0aQA
4OToh7+vFGatwxsGCS6utazdhmx0UT/LhO/GEF4G1zOb7eVa4ZtS1NKLP2WjPD1E
RU3Qn8wa0pESv3tJScv8qo2+PWVX4krbFllhY2Hk0AkVQcI66ExkdVq4ikm1eUXn
rxzIayLG2bv3KEPNCzozdwoY9tDL+b40q6vN/RHGJmM05SZbbSx2/Bkw2RbslSpD
2hvhHWX7xeuEBcd5mZO7sP4WS3hM/BI8eX7q+uMeNJ9B+nM82yjGfOTtglVi2cc=
=JfvQ
-----END PGP SIGNATURE-----
Merge tag 'kvm-arm-for-v4.12-round2' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD
Second round of KVM/ARM Changes for v4.12.
Changes include:
- A fix related to the 32-bit idmap stub
- A fix to the bitmask used to deode the operands of an AArch32 CP
instruction
- We have moved the files shared between arch/arm/kvm and
arch/arm64/kvm to virt/kvm/arm
- We add support for saving/restoring the virtual ITS state to
userspace
There are occasional needs to use the index of vcpu in the kvm->vcpus
array to map something related to a VCPU. For example, unlike the
vcpu->vcpu_id, the vcpu index is guaranteed to not be sparse across all
vcpus which is useful when allocating a memory area for each vcpu.
Signed-off-by: Christoffer Dall <cdall@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
The main thing here is a new implementation of the in-kernel
XICS interrupt controller emulation for POWER9 machines, from Ben
Herrenschmidt.
POWER9 has a new interrupt controller called XIVE (eXternal Interrupt
Virtualization Engine) which is able to deliver interrupts directly
to guest virtual CPUs in hardware without hypervisor intervention.
With this new code, the guest still sees the old XICS interface but
performance is better because the XICS emulation in the host uses the
XIVE directly rather than going through a XICS emulation in firmware.
Conflicts:
arch/powerpc/kernel/cpu_setup_power.S [cherry-picked fix]
arch/powerpc/kvm/book3s_xive.c [include asm/debugfs.h]
Merge more updates from Andrew Morton:
- the rest of MM
- various misc things
- procfs updates
- lib/ updates
- checkpatch updates
- kdump/kexec updates
- add kvmalloc helpers, use them
- time helper updates for Y2038 issues. We're almost ready to remove
current_fs_time() but that awaits a btrfs merge.
- add tracepoints to DAX
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (114 commits)
drivers/staging/ccree/ssi_hash.c: fix build with gcc-4.4.4
selftests/vm: add a test for virtual address range mapping
dax: add tracepoint to dax_insert_mapping()
dax: add tracepoint to dax_writeback_one()
dax: add tracepoints to dax_writeback_mapping_range()
dax: add tracepoints to dax_load_hole()
dax: add tracepoints to dax_pfn_mkwrite()
dax: add tracepoints to dax_iomap_pte_fault()
mtd: nand: nandsim: convert to memalloc_noreclaim_*()
treewide: convert PF_MEMALLOC manipulations to new helpers
mm: introduce memalloc_noreclaim_{save,restore}
mm: prevent potential recursive reclaim due to clearing PF_MEMALLOC
mm/huge_memory.c: deposit a pgtable for DAX PMD faults when required
mm/huge_memory.c: use zap_deposited_table() more
time: delete CURRENT_TIME_SEC and CURRENT_TIME
gfs2: replace CURRENT_TIME with current_time
apparmorfs: replace CURRENT_TIME with current_time()
lustre: replace CURRENT_TIME macro
fs: ubifs: replace CURRENT_TIME_SEC with current_time
fs: ufs: use ktime_get_real_ts64() for birthtime
...
Patch series "kvmalloc", v5.
There are many open coded kmalloc with vmalloc fallback instances in the
tree. Most of them are not careful enough or simply do not care about
the underlying semantic of the kmalloc/page allocator which means that
a) some vmalloc fallbacks are basically unreachable because the kmalloc
part will keep retrying until it succeeds b) the page allocator can
invoke a really disruptive steps like the OOM killer to move forward
which doesn't sound appropriate when we consider that the vmalloc
fallback is available.
As it can be seen implementing kvmalloc requires quite an intimate
knowledge if the page allocator and the memory reclaim internals which
strongly suggests that a helper should be implemented in the memory
subsystem proper.
Most callers, I could find, have been converted to use the helper
instead. This is patch 6. There are some more relying on __GFP_REPEAT
in the networking stack which I have converted as well and Eric Dumazet
was not opposed [2] to convert them as well.
[1] http://lkml.kernel.org/r/20170130094940.13546-1-mhocko@kernel.org
[2] http://lkml.kernel.org/r/1485273626.16328.301.camel@edumazet-glaptop3.roam.corp.google.com
This patch (of 9):
Using kmalloc with the vmalloc fallback for larger allocations is a
common pattern in the kernel code. Yet we do not have any common helper
for that and so users have invented their own helpers. Some of them are
really creative when doing so. Let's just add kv[mz]alloc and make sure
it is implemented properly. This implementation makes sure to not make
a large memory pressure for > PAGE_SZE requests (__GFP_NORETRY) and also
to not warn about allocation failures. This also rules out the OOM
killer as the vmalloc is a more approapriate fallback than a disruptive
user visible action.
This patch also changes some existing users and removes helpers which
are specific for them. In some cases this is not possible (e.g.
ext4_kvmalloc, libcfs_kvzalloc) because those seems to be broken and
require GFP_NO{FS,IO} context which is not vmalloc compatible in general
(note that the page table allocation is GFP_KERNEL). Those need to be
fixed separately.
While we are at it, document that __vmalloc{_node} about unsupported gfp
mask because there seems to be a lot of confusion out there.
kvmalloc_node will warn about GFP_KERNEL incompatible (which are not
superset) flags to catch new abusers. Existing ones would have to die
slowly.
[sfr@canb.auug.org.au: f2fs fixup]
Link: http://lkml.kernel.org/r/20170320163735.332e64b7@canb.auug.org.au
Link: http://lkml.kernel.org/r/20170306103032.2540-2-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Reviewed-by: Andreas Dilger <adilger@dilger.ca> [ext4 part]
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This reverts commit bbd6411513.
I've been sitting on this revert for too long and it unfortunately
missed 4.11. It's also the reason why I haven't merged ring-based
dirty tracking for 4.12.
Using kvm_vcpu_memslots in kvm_gfn_to_hva_cache_init and
kvm_vcpu_write_guest_offset_cached means that the MSR value can
now be used to access SMRAM, simply by making it point to an SMRAM
physical address. This is problematic because it lets the guest
OS overwrite memory that it shouldn't be able to touch.
Cc: stable@vger.kernel.org
Fixes: bbd6411513
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
We needed the lock to avoid racing with creation of the irqchip on x86. As
kvm_set_irq_routing() calls srcu_synchronize_expedited(), this lock
might be held for a longer time.
Let's introduce an arch specific callback to check if we can actually
add irq routes. For x86, all we have to do is check if we have an
irqchip in the kernel. We don't need kvm->lock at that point as the
irqchip is marked as inititalized only when actually fully created.
Reported-by: Steve Rutherford <srutherford@google.com>
Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Fixes: 1df6ddede1 ("KVM: x86: race between KVM_SET_GSI_ROUTING and KVM_CREATE_IRQCHIP")
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This merges in the powerpc topic/xive branch to bring in the code for
the in-kernel XICS interrupt controller emulation to use the new XIVE
(eXternal Interrupt Virtualization Engine) hardware in the POWER9 chip
directly, rather than via a XICS emulation in firmware.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
kvm_make_all_requests() provides a synchronization that waits until all
kicked VCPUs have acknowledged the kick. This is important for
KVM_REQ_MMU_RELOAD as it prevents freeing while lockless paging is
underway.
This patch adds the synchronization property into all requests that are
currently being used with kvm_make_all_requests() in order to preserve
the current behavior and only introduce a new framework. Removing it
from requests where it is not necessary is left for future patches.
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
No need to kick a VCPU that we have just woken up.
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
kvm_vcpu_kick() must issue a general memory barrier prior to reading
vcpu->mode in order to ensure correctness of the mutual-exclusion
memory barrier pattern used with vcpu->requests. While the cmpxchg
called from kvm_vcpu_kick():
kvm_vcpu_kick
kvm_arch_vcpu_should_kick
kvm_vcpu_exiting_guest_mode
cmpxchg
implies general memory barriers before and after the operation, that
implication is only valid when cmpxchg succeeds. We need an explicit
barrier for when it fails, otherwise a VCPU thread on its entry path
that reads zero for vcpu->requests does not exclude the possibility
the requesting thread sees !IN_GUEST_MODE when it reads vcpu->mode.
kvm_make_all_cpus_request already had a barrier, so we remove it, as
now it would be redundant.
Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Some operations must ensure that the guest is not running with stale
data, but if the guest is halted, then the update can wait until another
event happens. kvm_make_all_requests() currently doesn't wake up, so we
can mark all requests used with it.
First 8 bits were arbitrarily reserved for request numbers.
Most uses of requests have the request type as a constant, so a compiler
will optimize the '&'.
An alternative would be to have an inline function that would return
whether the request needs a wake-up or not, but I like this one better
even though it might produce worse assembly.
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Users were expected to use kvm_check_request() for testing and clearing,
but request have expanded their use since then and some users want to
only test or do a faster clear.
Make sure that requests are not directly accessed with bit operations.
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This patch makes KVM capable of using the XIVE interrupt controller
to provide the standard PAPR "XICS" style hypercalls. It is necessary
for proper operations when the host uses XIVE natively.
This has been lightly tested on an actual system, including PCI
pass-through with a TG3 device.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
[mpe: Cleanup pr_xxx(), unsplit pr_xxx() strings, etc., fix build
failures by adding KVM_XIVE which depends on KVM_XICS and XIVE, and
adding empty stubs for the kvm_xive_xxx() routines, fixup subject,
integrate fixes from Paul for building PR=y HV=n]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Parallelizing SRCU callback handling will increase the size of
srcu_struct, which will move the kvm structure's kvm_arch field out
of reach of powerpc's current assembly code, which will result in the
following sort of build error:
arch/powerpc/kvm/book3s_hv_rmhandlers.S:617: Error: operand out of range (0x000000000000b328 is not between 0xffffffffffff8000 and 0x0000000000007fff)
This commit moves the srcu_struct fields in the kvm structure to follow
the kvm_arch field, which will allow powerpc's assembly code to continue
to be able to reach the kvm_arch field.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Reported-by: Michael Ellerman <michaele@au1.ibm.com>
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
[ paulmck: Moved this commit to precede SRCU callback parallelization,
and reworded the commit log into future tense, all in the name of
bisectability. ]
Let's rename it into a proper arch specific callback.
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Its value has never changed; we might as well make it part of the ABI instead
of using the return value of KVM_CHECK_EXTENSION(KVM_CAP_COALESCED_MMIO).
Because PPC does not always make MMIO available, the code has to be made
dependent on CONFIG_KVM_MMIO rather than KVM_COALESCED_MMIO_PAGE_OFFSET.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Legacy device assignment has been deprecated since 4.2 (released
1.5 years ago). VFIO is better and everyone should have switched to it.
If they haven't, this should convince them. :)
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
No caller currently checks the return value of
kvm_io_bus_unregister_dev(). This is evil, as all callers silently go on
freeing their device. A stale reference will remain in the io_bus,
getting at least used again, when the iobus gets teared down on
kvm_destroy_vm() - leading to use after free errors.
There is nothing the callers could do, except retrying over and over
again.
So let's simply remove the bus altogether, print an error and make
sure no one can access this broken bus again (returning -ENOMEM on any
attempt to access it).
Fixes: e93f8a0f82 ("KVM: convert io_bus to SRCU")
Cc: stable@vger.kernel.org # 3.4+
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
The FPU is always active now when running KVM.
Reviewed-by: David Matlack <dmatlack@google.com>
Reviewed-by: Bandan Das <bsd@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Provide versions of struct gfn_to_hva_cache functions that
take vcpu as a parameter instead of struct kvm. The existing functions
are not needed anymore, so delete them. This allows dirty pages to
be logged in the vcpu dirty ring, instead of the global dirty ring,
for ring-based dirty memory tracking.
Signed-off-by: Lei Cao <lei.cao@stratus.com>
Message-Id: <CY1PR08MB19929BD2AC47A291FD680E83F04F0@CY1PR08MB1992.namprd08.prod.outlook.com>
Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM_MEMSLOT_INCOHERENT is not used anymore, as we've killed its
only use in the arm/arm64 MMU code. Let's remove the last artifacts.
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
x86: userspace can now hide nested VMX features from guests; nested
VMX can now run Hyper-V in a guest; support for AVX512_4VNNIW and
AVX512_FMAPS in KVM; infrastructure support for virtual Intel GPUs.
PPC: support for KVM guests on POWER9; improved support for interrupt
polling; optimizations and cleanups.
s390: two small optimizations, more stuff is in flight and will be
in 4.11.
ARM: support for the GICv3 ITS on 32bit platforms.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2
iQExBAABCAAbBQJYTkP0FBxwYm9uemluaUByZWRoYXQuY29tAAoJEL/70l94x66D
lZIH/iT1n9OQXcuTpYYnQhuCenzI3GZZOIMTbCvK2i5bo0FIJKxVn0EiAAqZSXvO
nO185FqjOgLuJ1AD1kJuxzye5suuQp4HIPWWgNHcexLuy43WXWKZe0IQlJ4zM2Xf
u31HakpFmVDD+Cd1qN3yDXtDrRQ79/xQn2kw7CWb8olp+pVqwbceN3IVie9QYU+3
gCz0qU6As0aQIwq2PyalOe03sO10PZlm4XhsoXgWPG7P18BMRhNLTDqhLhu7A/ry
qElVMANT7LSNLzlwNdpzdK8rVuKxETwjlc1UP8vSuhrwad4zM2JJ1Exk26nC2NaG
D0j4tRSyGFIdx6lukZm7HmiSHZ0=
=mkoB
-----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, the most interesting stuff is x86 nested virt
improvements.
x86:
- userspace can now hide nested VMX features from guests
- nested VMX can now run Hyper-V in a guest
- support for AVX512_4VNNIW and AVX512_FMAPS in KVM
- infrastructure support for virtual Intel GPUs.
PPC:
- support for KVM guests on POWER9
- improved support for interrupt polling
- optimizations and cleanups.
s390:
- two small optimizations, more stuff is in flight and will be in
4.11.
ARM:
- support for the GICv3 ITS on 32bit platforms"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (94 commits)
arm64: KVM: pmu: Reset PMSELR_EL0.SEL to a sane value before entering the guest
KVM: arm/arm64: timer: Check for properly initialized timer on init
KVM: arm/arm64: vgic-v2: Limit ITARGETSR bits to number of VCPUs
KVM: x86: Handle the kthread worker using the new API
KVM: nVMX: invvpid handling improvements
KVM: nVMX: check host CR3 on vmentry and vmexit
KVM: nVMX: introduce nested_vmx_load_cr3 and call it on vmentry
KVM: nVMX: propagate errors from prepare_vmcs02
KVM: nVMX: fix CR3 load if L2 uses PAE paging and EPT
KVM: nVMX: load GUEST_EFER after GUEST_CR0 during emulated VM-entry
KVM: nVMX: generate MSR_IA32_CR{0,4}_FIXED1 from guest CPUID
KVM: nVMX: fix checks on CR{0,4} during virtual VMX operation
KVM: nVMX: support restore of VMX capability MSRs
KVM: nVMX: generate non-true VMX MSRs based on true versions
KVM: x86: Do not clear RFLAGS.TF when a singlestep trap occurs.
KVM: x86: Add kvm_skip_emulated_instruction and use it.
KVM: VMX: Move skip_emulated_instruction out of nested_vmx_check_vmcs12
KVM: VMX: Reorder some skip_emulated_instruction calls
KVM: x86: Add a return value to kvm_emulate_cpuid
KVM: PPC: Book3S: Move prototypes for KVM functions into kvm_ppc.h
...
Pull x86 FPU updates from Ingo Molnar:
"The main changes in this cycle were:
- do a large round of simplifications after all CPUs do 'eager' FPU
context switching in v4.9: remove CR0 twiddling, remove leftover
eager/lazy bts, etc (Andy Lutomirski)
- more FPU code simplifications: remove struct fpu::counter, clarify
nomenclature, remove unnecessary arguments/functions and better
structure the code (Rik van Riel)"
* 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/fpu: Remove clts()
x86/fpu: Remove stts()
x86/fpu: Handle #NM without FPU emulation as an error
x86/fpu, lguest: Remove CR0.TS support
x86/fpu, kvm: Remove host CR0.TS manipulation
x86/fpu: Remove irq_ts_save() and irq_ts_restore()
x86/fpu: Stop saving and restoring CR0.TS in fpu__init_check_bugs()
x86/fpu: Get rid of two redundant clts() calls
x86/fpu: Finish excising 'eagerfpu'
x86/fpu: Split old_fpu & new_fpu handling into separate functions
x86/fpu: Remove 'cpu' argument from __cpu_invalidate_fpregs_state()
x86/fpu: Split old & new FPU code paths
x86/fpu: Remove __fpregs_(de)activate()
x86/fpu: Rename lazy restore functions to "register state valid"
x86/fpu, kvm: Remove KVM vcpu->fpu_counter
x86/fpu: Remove struct fpu::counter
x86/fpu: Remove use_eager_fpu()
x86/fpu: Remove the XFEATURE_MASK_EAGER/LAZY distinction
x86/fpu: Hard-disable lazy FPU mode
x86/crypto, x86/fpu: Remove X86_FEATURE_EAGER_FPU #ifdef from the crc32c code
PPC KVM update for 4.10:
* Support for KVM guests on POWER9 using the hashed page table MMU.
* Updates and improvements to the halt-polling support on PPC, from
Suraj Jitindar Singh.
* An optimization to speed up emulated MMIO, from Yongji Xie.
* Various other minor cleanups.
The kvm module has the parameters halt_poll_ns, halt_poll_ns_grow, and
halt_poll_ns_shrink. Halt polling was recently added to the powerpc kvm-hv
module and these parameters were essentially duplicated for that. There is
no benefit to this duplication and it can lead to confusion when trying to
tune halt polling.
Thus move the definition of these variables to kvm_host.h and export them.
This will allow the kvm-hv module to use the same module parameters by
accessing these variables, which will be implemented in the next patch,
meaning that they will no longer be duplicated.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Change unimplemented msrs messages to use pr_debug.
If CONFIG_DYNAMIC_DEBUG is set, then these messages can be
enabled at run time or else -DDEBUG can be used at compile
time to enable them. These messages will still be printed if
ignore_msrs=1.
Signed-off-by: Bandan Das <bsd@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
With the removal of the lazy FPU code, this field is no longer used.
Get rid of it.
Signed-off-by: Rik van Riel <riel@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: pbonzini@redhat.com
Link: http://lkml.kernel.org/r/1475627678-20788-7-git-send-email-riel@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit adds the ability for archs to export
per-vcpu information via a new per-vcpu dir in
the VM's debugfs directory.
If kvm_arch_has_vcpu_debugfs() returns true, then KVM
will create a vcpu dir for each vCPU in the VM's
debugfs directory. Then kvm_arch_create_vcpu_debugfs()
is responsible for populating each vcpu directory
with arch specific entries.
The per-vcpu path in debugfs will look like:
/sys/kernel/debug/kvm/29162-10/vcpu0
/sys/kernel/debug/kvm/29162-10/vcpu1
This is all arch specific for now because the only
user of this interface (x86) wants to export x86-specific
per-vcpu information to user-space.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Two stubs are added:
o kvm_arch_has_vcpu_debugfs(): must return true if the arch
supports creating debugfs entries in the vcpu debugfs dir
(which will be implemented by the next commit)
o kvm_arch_create_vcpu_debugfs(): code that creates debugfs
entries in the vcpu debugfs dir
For x86, this commit introduces a new file to avoid growing
arch/x86/kvm/x86.c even more.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM devices were manipulating list data structures without any form of
synchronization, and some implementations of the create operations also
suffered from a lack of synchronization.
Now when we've split the xics create operation into create and init, we
can hold the kvm->lock mutex while calling the create operation and when
manipulating the devices list.
The error path in the generic code gets slightly ugly because we have to
take the mutex again and delete the device from the list, but holding
the mutex during anon_inode_getfd or releasing/locking the mutex in the
common non-error path seemed wrong.
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
As we are about to hold the kvm->lock during the create operation on KVM
devices, we should move the call to xics_debugfs_init into its own
function, since holding a mutex over extended amounts of time might not
be a good idea.
Introduce an init operation on the kvm_device_ops struct which cannot
fail and call this, if configured, after the device has been created.
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Includes GSI routing support to go along with the new VGIC and a small fix that
has been cooking in -next for a while.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1
iQEcBAABAgAGBQJXoydqAAoJEEtpOizt6ddyM3oH/1A4VeG/J9q4fBPXqY2tVWXs
c3P7UgNcrEgUNs/F9ykQY/lb31deecUzaBt1OyTf+RlsNbihq3dQdYcBhxtUODw/
Faok582ya3UFgLW+IRHcID0EbkVOpIzMhOStYsnU/Dz7HG1JL9HdPzwkid7iu9LT
fI6yrrBnJFjdWAAQ4BkcEKBENRsY8NTs7jX5vnFA92MkUBby7BmariPDD3FtrB+f
Ob9B7CxM30pNqsN7OA/QvFOHMJHxf3s1TBKwmPHe5TLIfSzV1YxcEGiMc0lWqF4v
BT8ZeMGCtjDw94tND1DskfQQRPaMqPmGuRTrAW/IuE2n92bFtbqIqs7Cbw0fzLE=
=Vm6Q
-----END PGP SIGNATURE-----
Merge tag 'kvm-arm-for-4.8-take2' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD
KVM/ARM Changes for v4.8 - Take 2
Includes GSI routing support to go along with the new VGIC and a small fix that
has been cooking in -next for a while.
- GICv3 ITS emulation
- Simpler idmap management that fixes potential TLB conflicts
- Honor the kernel protection in HYP mode
- Removal of the old vgic implementation
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1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=2Del
-----END PGP SIGNATURE-----
Merge tag 'kvm-arm-for-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into next
KVM/ARM changes for Linux 4.8
- GICv3 ITS emulation
- Simpler idmap management that fixes potential TLB conflicts
- Honor the kernel protection in HYP mode
- Removal of the old vgic implementation
Longpeng(Mike)
David Hildenbrand
Paolo Bonzini
Claudio Imbrenda
Christian Borntraeger
Radim Krčmář
Andrew Jones
Linus Torvalds
Christoffer Dall
Michal Hocko
Paul Mackerras
Benjamin Herrenschmidt
Ingo Molnar
Paul E. McKenney
Elena Reshetova
Cao, Lei
Marc Zyngier
Suraj Jitindar Singh
Bandan Das
Pan Xinhui
Rik van Riel
Luiz Capitulino
Christoffer Dall