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  1. 31 Mar, 2017 10 commits
  3. 30 Mar, 2017 8 commits
  5. 29 Mar, 2017 17 commits
  7. 28 Mar, 2017 5 commits
    • Linus Torvalds's avatar
      Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost · fe82203b
      Linus Torvalds authored 
      Pull virtio fixes from Michael Tsirkin:
 "Fixes to multiple issues in virtio.

  Most notably a regression fix for crashes reported by Fedora users.
  Hibernate is still reportedly broken, working on it"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  virtio_balloon: prevent uninitialized variable use
  virtio-balloon: use actual number of stats for stats queue buffers
  virtio_balloon: init 1st buffer in stats vq
  virtio_pci: fix out of bound access for msix_names
      fe82203b
    • Linus Torvalds's avatar
      Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm · 050fc52d
      Linus Torvalds authored 
      Pull KVM fixes from Paolo Bonzini:
 "All x86-specific, apart from some arch-independent syzkaller fixes"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: x86: cleanup the page tracking SRCU instance
  KVM: nVMX: fix nested EPT detection
  KVM: pci-assign: do not map smm memory slot pages in vt-d page tables
  KVM: kvm_io_bus_unregister_dev() should never fail
  KVM: VMX: Fix enable VPID conditions
  KVM: nVMX: Fix nested VPID vmx exec control
  KVM: x86: correct async page present tracepoint
  kvm: vmx: Flush TLB when the APIC-access address changes
  KVM: x86: use pic/ioapic destructor when destroy vm
  KVM: x86: check existance before destroy
  KVM: x86: clear bus pointer when destroyed
  KVM: Documentation: document MCE ioctls
  KVM: nVMX: don't reset kvm mmu twice
  PTP: fix ptr_ret.cocci warnings
  kvm: fix usage of uninit spinlock in avic_vm_destroy()
  KVM: VMX: downgrade warning on unexpected exit code
      050fc52d
    • Arnd Bergmann's avatar
      virtio_balloon: prevent uninitialized variable use · f0bb2d50
      Arnd Bergmann authored 
      The latest gcc-7.0.1 snapshot reports a new warning:

virtio/virtio_balloon.c: In function 'update_balloon_stats':
virtio/virtio_balloon.c:258:26: error: 'events[2]' is used uninitialized in this function [-Werror=uninitialized]
virtio/virtio_balloon.c:260:26: error: 'events[3]' is used uninitialized in this function [-Werror=uninitialized]
virtio/virtio_balloon.c:261:56: error: 'events[18]' is used uninitialized in this function [-Werror=uninitialized]
virtio/virtio_balloon.c:262:56: error: 'events[17]' is used uninitialized in this function [-Werror=uninitialized]

This seems absolutely right, so we should add an extra check to
prevent copying uninitialized stack data into the statistics.
>From all I can tell, this has been broken since the statistics code
was originally added in 2.6.34.

Fixes: 9564e138 ("virtio: Add memory statistics reporting to the balloon driver (V4)")
Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
Signed-off-by: default avatarLadi Prosek <lprosek@redhat.com>
Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
      f0bb2d50
    • Ladi Prosek's avatar
      virtio-balloon: use actual number of stats for stats queue buffers · 9646b26e
      Ladi Prosek authored 
      The virtio balloon driver contained a not-so-obvious invariant that
update_balloon_stats has to update exactly VIRTIO_BALLOON_S_NR counters
in order to send valid stats to the host. This commit fixes it by having
update_balloon_stats return the actual number of counters, and its
callers use it when pushing buffers to the stats virtqueue.

Note that it is still out of spec to change the number of counters
at run-time. "Driver MUST supply the same subset of statistics in all
buffers submitted to the statsq."
Suggested-by: default avatarArnd Bergmann <arnd@arndb.de>
Signed-off-by: default avatarLadi Prosek <lprosek@redhat.com>
Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
      9646b26e
    • Ladi Prosek's avatar
      virtio_balloon: init 1st buffer in stats vq · fc865322
      Ladi Prosek authored 
      When init_vqs runs, virtio_balloon.stats is either uninitialized or
contains stale values. The host updates its state with garbage data
because it has no way of knowing that this is just a marker buffer
used for signaling.

This patch updates the stats before pushing the initial buffer.

Alternative fixes:
* Push an empty buffer in init_vqs. Not easily done with the current
  virtio implementation and violates the spec "Driver MUST supply the
  same subset of statistics in all buffers submitted to the statsq".
* Push a buffer with invalid tags in init_vqs. Violates the same
  spec clause, plus "invalid tag" is not really defined.

Note: the spec says:
	When using the legacy interface, the device SHOULD ignore all values in
	the first buffer in the statsq supplied by the driver after device
	initialization. Note: Historically, drivers supplied an uninitialized
	buffer in the first buffer.

Unfortunately QEMU does not seem to implement the recommendation
even for the legacy interface.

Cc: stable@vger.kernel.org
Signed-off-by: default avatarLadi Prosek <lprosek@redhat.com>
Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
      fc865322
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