Commit Graph

623 Commits

Author SHA1 Message Date
Paolo Bonzini 525df86145 KVM: explain missing kvm_put_kvm in case of failure
The call to kvm_put_kvm was removed from error handling in commit
506cfba9e7 ("KVM: don't use anon_inode_getfd() before possible
failures"), but it is _not_ a memory leak.  Reuse Al's explanation
to avoid that someone else makes the same mistake.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-06-27 15:45:09 +02:00
Roman Storozhenko 039c5d1b2c KVM: Replaces symbolic permissions with numeric
Replaces "S_IRUGO | S_IWUSR" with 0644. The reason is that symbolic
permissions considered harmful:
https://lwn.net/Articles/696229/

Signed-off-by: Roman Storozhenko <romeusmeister@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-06-27 15:41:02 +02:00
Paolo Bonzini 4415b33528 Merge branch 'kvm-ppc-next' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc into HEAD
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]
2017-05-09 11:50:01 +02:00
Geliang Tang 3bed8888ed KVM: set no_llseek in stat_fops_per_vm
In vm_stat_get_per_vm_fops and vcpu_stat_get_per_vm_fops, since we
use nonseekable_open() to open, we should use no_llseek() to seek,
not generic_file_llseek().

Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-05-09 11:48:23 +02:00
Linus Torvalds bf5f89463f Merge branch 'akpm' (patches from Andrew)
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
  ...
2017-05-08 18:17:56 -07:00
Michal Hocko a7c3e901a4 mm: introduce kv[mz]alloc helpers
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>
2017-05-08 17:15:12 -07:00
Paolo Bonzini 0266c894b5 KVM: put back #ifndef CONFIG_S390 around kvm_vcpu_kick
The #ifndef was removed in 75aaafb79f,
but it was also protecting smp_send_reschedule() in kvm_vcpu_kick().

Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-05-04 15:14:13 +02:00
Paolo Bonzini 4e335d9e7d Revert "KVM: Support vCPU-based gfn->hva cache"
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>
2017-05-03 16:30:26 +02:00
David Hildenbrand 5c0aea0e8d KVM: x86: don't hold kvm->lock in KVM_SET_GSI_ROUTING
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>
2017-05-02 14:45:45 +02:00
Paul Mackerras fb7dcf723d Merge remote-tracking branch 'remotes/powerpc/topic/xive' into kvm-ppc-next
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>
2017-04-28 08:23:16 +10:00
Paolo Bonzini 7a97cec26b KVM: mark requests that need synchronization
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>
2017-04-27 14:36:44 +02:00
Radim Krčmář 178f02ffaf KVM: return if kvm_vcpu_wake_up() did wake up the VCPU
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>
2017-04-27 14:18:45 +02:00
Andrew Jones cde9af6e79 KVM: add explicit barrier to kvm_vcpu_kick
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>
2017-04-27 14:16:17 +02:00
Radim Krčmář 6c6e8360b3 KVM: perform a wake_up in kvm_make_all_cpus_request
We want to have kvm_make_all_cpus_request() to be an optmized version of

  kvm_for_each_vcpu(i, vcpu, kvm) {
    kvm_make_request(vcpu, request);
    kvm_vcpu_kick(vcpu);
  }

and kvm_vcpu_kick() wakes up the target vcpu.  We know which requests do
not need the wake up and use it to optimize the loop.

Thanks to that, this patch doesn't change the behavior of current users
(the all don't need the wake up) and only prepares for future where the
wake up is going to be needed.

I think that most requests do not need the wake up, so we would flip the
bit then.

Later on, kvm_make_request() will take care of kicking too, using this
bit to make the decision whether to kick or not.

Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-04-27 14:14:33 +02:00
Radim Krčmář 75aaafb79f KVM: remove #ifndef CONFIG_S390 around kvm_vcpu_wake_up
The #ifndef was protecting a missing halt_wakeup stat, but that is no
longer necessary.

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-04-27 14:13:32 +02:00
Benjamin Herrenschmidt 5af5099385 KVM: PPC: Book3S HV: Native usage of the XIVE interrupt controller
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>
2017-04-27 21:37:29 +10:00
David Hildenbrand 1df6ddede1 KVM: x86: race between KVM_SET_GSI_ROUTING and KVM_CREATE_IRQCHIP
Avoid races between KVM_SET_GSI_ROUTING and KVM_CREATE_IRQCHIP by taking
the kvm->lock when setting up routes.

If KVM_CREATE_IRQCHIP fails, KVM_SET_GSI_ROUTING could have already set
up routes pointing at pic/ioapic, being silently removed already.

Also, as a side effect, this patch makes sure that KVM_SET_GSI_ROUTING
and KVM_CAP_SPLIT_IRQCHIP cannot run in parallel.

Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-04-12 20:17:13 +02:00
Paolo Bonzini 4b4357e025 kvm: make KVM_COALESCED_MMIO_PAGE_OFFSET public
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>
2017-04-07 16:49:01 +02:00
Paolo Bonzini 3042255899 kvm: make KVM_CAP_COALESCED_MMIO architecture agnostic
Remove code from architecture files that can be moved to virt/kvm, since there
is already common code for coalesced MMIO.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
[Removed a pointless 'break' after 'return'.]
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-04-07 16:49:00 +02:00
Paolo Bonzini ad6260da1e KVM: x86: drop legacy device assignment
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>
2017-04-07 16:49:00 +02:00
Herongguang (Stephen) 0292e169b2 KVM: pci-assign: do not map smm memory slot pages in vt-d page tables
or VM memory are not put thus leaked in kvm_iommu_unmap_memslots() when
destroy VM.

This is consistent with current vfio implementation.

Signed-off-by: herongguang <herongguang.he@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-03-28 10:08:54 +02:00
David Hildenbrand 90db10434b KVM: kvm_io_bus_unregister_dev() should never fail
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>
2017-03-23 19:02:25 +01:00
Peter Xu df630b8c1e KVM: x86: clear bus pointer when destroyed
When releasing the bus, let's clear the bus pointers to mark it out. If
any further device unregister happens on this bus, we know that we're
done if we found the bus being released already.

Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-03-21 17:11:18 +01:00
Linus Torvalds 2d62e0768d Second batch of KVM changes for 4.11 merge window
PPC:
  * correct assumption about ASDR on POWER9
  * fix MMIO emulation on POWER9
 
 x86:
  * add a simple test for ioperm
  * cleanup TSS
    (going through KVM tree as the whole undertaking was caused by VMX's
     use of TSS)
  * fix nVMX interrupt delivery
  * fix some performance counters in the guest
 
 And two cleanup patches.
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Merge tag 'kvm-4.11-2' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull more KVM updates from Radim Krčmář:
 "Second batch of KVM changes for the 4.11 merge window:

  PPC:
   - correct assumption about ASDR on POWER9
   - fix MMIO emulation on POWER9

  x86:
   - add a simple test for ioperm
   - cleanup TSS (going through KVM tree as the whole undertaking was
     caused by VMX's use of TSS)
   - fix nVMX interrupt delivery
   - fix some performance counters in the guest

  ... and two cleanup patches"

* tag 'kvm-4.11-2' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: nVMX: Fix pending events injection
  x86/kvm/vmx: remove unused variable in segment_base()
  selftests/x86: Add a basic selftest for ioperm
  x86/asm: Tidy up TSS limit code
  kvm: convert kvm.users_count from atomic_t to refcount_t
  KVM: x86: never specify a sample period for virtualized in_tx_cp counters
  KVM: PPC: Book3S HV: Don't use ASDR for real-mode HPT faults on POWER9
  KVM: PPC: Book3S HV: Fix software walk of guest process page tables
2017-03-04 11:36:19 -08:00
Ingo Molnar 03441a3482 sched/headers: Prepare for new header dependencies before moving code to <linux/sched/stat.h>
We are going to split <linux/sched/stat.h> out of <linux/sched.h>, which
will have to be picked up from other headers and a couple of .c files.

Create a trivial placeholder <linux/sched/stat.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.

Include the new header in the files that are going to need it.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02 08:42:34 +01:00
Ingo Molnar 174cd4b1e5 sched/headers: Prepare to move signal wakeup & sigpending methods from <linux/sched.h> into <linux/sched/signal.h>
Fix up affected files that include this signal functionality via sched.h.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02 08:42:32 +01:00
Ingo Molnar 6e84f31522 sched/headers: Prepare for new header dependencies before moving code to <linux/sched/mm.h>
We are going to split <linux/sched/mm.h> out of <linux/sched.h>, which
will have to be picked up from other headers and a couple of .c files.

Create a trivial placeholder <linux/sched/mm.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.

The APIs that are going to be moved first are:

   mm_alloc()
   __mmdrop()
   mmdrop()
   mmdrop_async_fn()
   mmdrop_async()
   mmget_not_zero()
   mmput()
   mmput_async()
   get_task_mm()
   mm_access()
   mm_release()

Include the new header in the files that are going to need it.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02 08:42:28 +01:00
Elena Reshetova e3736c3eb3 kvm: convert kvm.users_count from atomic_t to refcount_t
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>
2017-03-01 17:03:21 +01:00
Vegard Nossum f1f1007644 mm: add new mmgrab() helper
Apart from adding the helper function itself, the rest of the kernel is
converted mechanically using:

  git grep -l 'atomic_inc.*mm_count' | xargs sed -i 's/atomic_inc(&\(.*\)->mm_count);/mmgrab\(\1\);/'
  git grep -l 'atomic_inc.*mm_count' | xargs sed -i 's/atomic_inc(&\(.*\)\.mm_count);/mmgrab\(\&\1\);/'

This is needed for a later patch that hooks into the helper, but might
be a worthwhile cleanup on its own.

(Michal Hocko provided most of the kerneldoc comment.)

Link: http://lkml.kernel.org/r/20161218123229.22952-1-vegard.nossum@oracle.com
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-27 18:43:48 -08:00
Dave Jiang 11bac80004 mm, fs: reduce fault, page_mkwrite, and pfn_mkwrite to take only vmf
->fault(), ->page_mkwrite(), and ->pfn_mkwrite() calls do not need to
take a vma and vmf parameter when the vma already resides in vmf.

Remove the vma parameter to simplify things.

[arnd@arndb.de: fix ARM build]
  Link: http://lkml.kernel.org/r/20170125223558.1451224-1-arnd@arndb.de
Link: http://lkml.kernel.org/r/148521301778.19116.10840599906674778980.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jan Kara <jack@suse.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:54 -08:00
Markus Elfring 843574a3ed KVM: Return an error code only as a constant in kvm_get_dirty_log()
* Return an error code without storing it in an intermediate variable.

* Delete the local variable "r" and the jump label "out" which became
  unnecessary with this refactoring.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-02-17 12:30:14 +01:00
Markus Elfring 58d6db3491 KVM: Return an error code only as a constant in kvm_get_dirty_log_protect()
* Return an error code without storing it in an intermediate variable.

* Delete the local variable "r" and the jump label "out" which became
  unnecessary with this refactoring.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-02-17 12:30:06 +01:00
Markus Elfring f6a3b168e5 KVM: Return directly after a failed copy_from_user() in kvm_vm_compat_ioctl()
* Return directly after a call of the function "copy_from_user" failed
  in a case block.

  This issue was detected by using the Coccinelle software.

* Delete the jump label "out" which became unnecessary with
  this refactoring.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-02-17 12:29:42 +01:00
Cao, Lei bbd6411513 KVM: Support vCPU-based gfn->hva cache
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>
2017-02-16 18:42:46 +01:00
Paolo Bonzini 4bd518f159 KVM: use separate generations for each address space
This will make it easier to support multiple address spaces in
kvm_gfn_to_hva_cache_init.  Instead of having to check the address
space id, we can keep on checking just the generation number.

Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-02-16 18:42:41 +01:00
Paolo Bonzini 5a2d4365d2 KVM: only retrieve memslots once when initializing cache
This will make it a bit simpler to handle multiple address spaces
in gfn_to_hva_cache.

Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-02-16 18:42:33 +01:00
Linus Torvalds b272f732f8 Merge branch 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull SMP hotplug notifier removal from Thomas Gleixner:
 "This is the final cleanup of the hotplug notifier infrastructure. The
  series has been reintgrated in the last two days because there came a
  new driver using the old infrastructure via the SCSI tree.

  Summary:

   - convert the last leftover drivers utilizing notifiers

   - fixup for a completely broken hotplug user

   - prevent setup of already used states

   - removal of the notifiers

   - treewide cleanup of hotplug state names

   - consolidation of state space

  There is a sphinx based documentation pending, but that needs review
  from the documentation folks"

* 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/armada-xp: Consolidate hotplug state space
  irqchip/gic: Consolidate hotplug state space
  coresight/etm3/4x: Consolidate hotplug state space
  cpu/hotplug: Cleanup state names
  cpu/hotplug: Remove obsolete cpu hotplug register/unregister functions
  staging/lustre/libcfs: Convert to hotplug state machine
  scsi/bnx2i: Convert to hotplug state machine
  scsi/bnx2fc: Convert to hotplug state machine
  cpu/hotplug: Prevent overwriting of callbacks
  x86/msr: Remove bogus cleanup from the error path
  bus: arm-ccn: Prevent hotplug callback leak
  perf/x86/intel/cstate: Prevent hotplug callback leak
  ARM/imx/mmcd: Fix broken cpu hotplug handling
  scsi: qedi: Convert to hotplug state machine
2016-12-25 14:05:56 -08:00
Thomas Gleixner 73c1b41e63 cpu/hotplug: Cleanup state names
When the state names got added a script was used to add the extra argument
to the calls. The script basically converted the state constant to a
string, but the cleanup to convert these strings into meaningful ones did
not happen.

Replace all the useless strings with 'subsys/xxx/yyy:state' strings which
are used in all the other places already.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Link: http://lkml.kernel.org/r/20161221192112.085444152@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-12-25 10:47:44 +01:00
Linus Torvalds 7c0f6ba682 Replace <asm/uaccess.h> with <linux/uaccess.h> globally
This was entirely automated, using the script by Al:

  PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
  sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
        $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.

Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-24 11:46:01 -08:00
Lorenzo Stoakes 8b7457ef9a mm: unexport __get_user_pages_unlocked()
Unexport the low-level __get_user_pages_unlocked() function and replaces
invocations with calls to more appropriate higher-level functions.

In hva_to_pfn_slow() we are able to replace __get_user_pages_unlocked()
with get_user_pages_unlocked() since we can now pass gup_flags.

In async_pf_execute() and process_vm_rw_single_vec() we need to pass
different tsk, mm arguments so get_user_pages_remote() is the sane
replacement in these cases (having added manual acquisition and release
of mmap_sem.)

Additionally get_user_pages_remote() reintroduces use of the FOLL_TOUCH
flag.  However, this flag was originally silently dropped by commit
1e9877902d ("mm/gup: Introduce get_user_pages_remote()"), so this
appears to have been unintentional and reintroducing it is therefore not
an issue.

[akpm@linux-foundation.org: coding-style fixes]
Link: http://lkml.kernel.org/r/20161027095141.2569-3-lstoakes@gmail.com
Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Hugh Dickins <hughd@google.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krcmar <rkrcmar@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-14 16:04:09 -08:00
Linus Torvalds 93173b5bf2 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.
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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
  ...
2016-12-13 15:47:02 -08:00
Ingo Molnar 6f38751510 Merge branch 'linus' into locking/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-12-11 13:07:13 +01:00
Dan Carpenter a0f1d21c1c KVM: use after free in kvm_ioctl_create_device()
We should move the ops->destroy(dev) after the list_del(&dev->vm_node)
so that we don't use "dev" after freeing it.

Fixes: a28ebea2ad ("KVM: Protect device ops->create and list_add with kvm->lock")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2016-12-01 16:10:50 +01:00
Suraj Jitindar Singh ec76d819d2 KVM: Export kvm module parameter variables
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>
2016-11-28 11:48:47 +11:00
Pan Xinhui 4ec6e86362 kvm: Introduce kvm_write_guest_offset_cached()
It allows us to update some status or field of a structure partially.

We can also save a kvm_read_guest_cached() call if we just update one
fild of the struct regardless of its current value.

Signed-off-by: Pan Xinhui <xinhui.pan@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: David.Laight@ACULAB.COM
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: benh@kernel.crashing.org
Cc: boqun.feng@gmail.com
Cc: borntraeger@de.ibm.com
Cc: bsingharora@gmail.com
Cc: dave@stgolabs.net
Cc: jgross@suse.com
Cc: kernellwp@gmail.com
Cc: konrad.wilk@oracle.com
Cc: linuxppc-dev@lists.ozlabs.org
Cc: mpe@ellerman.id.au
Cc: paulmck@linux.vnet.ibm.com
Cc: paulus@samba.org
Cc: rkrcmar@redhat.com
Cc: virtualization@lists.linux-foundation.org
Cc: will.deacon@arm.com
Cc: xen-devel-request@lists.xenproject.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/1478077718-37424-8-git-send-email-xinhui.pan@linux.vnet.ibm.com
[ Typo fixes. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-22 12:48:07 +01:00
Radim Krčmář 813ae37e6a Merge branch 'x86/cpufeature' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into kvm/next
Topic branch for AVX512_4VNNIW and AVX512_4FMAPS support in KVM.
2016-11-16 22:07:36 +01:00
Linus Torvalds 66cecb6789 One NULL pointer dereference, and two fixes for regressions introduced
during the merge window.  The rest are fixes for MIPS, s390 and nested VMX.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "One NULL pointer dereference, and two fixes for regressions introduced
  during the merge window.

  The rest are fixes for MIPS, s390 and nested VMX"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  kvm: x86: Check memopp before dereference (CVE-2016-8630)
  kvm: nVMX: VMCLEAR an active shadow VMCS after last use
  KVM: x86: drop TSC offsetting kvm_x86_ops to fix KVM_GET/SET_CLOCK
  KVM: x86: fix wbinvd_dirty_mask use-after-free
  kvm/x86: Show WRMSR data is in hex
  kvm: nVMX: Fix kernel panics induced by illegal INVEPT/INVVPID types
  KVM: document lock orders
  KVM: fix OOPS on flush_work
  KVM: s390: Fix STHYI buffer alignment for diag224
  KVM: MIPS: Precalculate MMIO load resume PC
  KVM: MIPS: Make ERET handle ERL before EXL
  KVM: MIPS: Fix lazy user ASID regenerate for SMP
2016-11-04 13:08:05 -07:00
Suraj Jitindar Singh ce35ef27d4 kvm/stats: Update kvm stats to clear on write to their debugfs entry
Various kvm vm and vcpu stats are provided via debugfs entries.
Currently there is no way to reset these stats back to zero.

Add the ability to clear (reset back to zero) these stats on a per stat
basis by writing to the debugfs files. Only a write value of 0 is accepted.

Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2016-11-02 21:32:17 +01:00
Paolo Bonzini 36343f6ea7 KVM: fix OOPS on flush_work
The conversion done by commit 3706feacd0 ("KVM: Remove deprecated
create_singlethread_workqueue") is broken.  It flushes a single work
item &irqfd->shutdown instead of all of them, and even worse if there
is no irqfd on the list then you get a NULL pointer dereference.
Revert the virt/kvm/eventfd.c part of that patch; to avoid the
deprecated function, just allocate our own workqueue---it does
not even have to be unbound---with alloc_workqueue.

Fixes: 3706feacd0
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-10-26 14:06:51 +02:00
Lorenzo Stoakes 0d73175982 mm: unexport __get_user_pages()
This patch unexports the low-level __get_user_pages() function.

Recent refactoring of the get_user_pages* functions allow flags to be
passed through get_user_pages() which eliminates the need for access to
this function from its one user, kvm.

We can see that the two calls to get_user_pages() which replace
__get_user_pages() in kvm_main.c are equivalent by examining their call
stacks:

  get_user_page_nowait():
    get_user_pages(start, 1, flags, page, NULL)
    __get_user_pages_locked(current, current->mm, start, 1, page, NULL, NULL,
			    false, flags | FOLL_TOUCH)
    __get_user_pages(current, current->mm, start, 1,
		     flags | FOLL_TOUCH | FOLL_GET, page, NULL, NULL)

  check_user_page_hwpoison():
    get_user_pages(addr, 1, flags, NULL, NULL)
    __get_user_pages_locked(current, current->mm, addr, 1, NULL, NULL, NULL,
			    false, flags | FOLL_TOUCH)
    __get_user_pages(current, current->mm, addr, 1, flags | FOLL_TOUCH, NULL,
		     NULL, NULL)

Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-24 19:13:20 -07:00