linux-toradex.git/drivers/xen, branch v3.14.20

xen/manage: Always freeze/thaw processes when suspend/resuming

2014-10-05T21:52:17+00:00

commit 61a734d305e16944b42730ef582a7171dc733321 upstream.

Always freeze processes when suspending and thaw processes when resuming
to prevent a race noticeable with HVM guests.

This prevents a deadlock where the khubd kthread (which is designed to
be freezable) acquires a usb device lock and then tries to allocate
memory which requires the disk which hasn't been resumed yet.
Meanwhile, the xenwatch thread deadlocks waiting for the usb device
lock.

Freezing processes fixes this because the khubd thread is only thawed
after the xenwatch thread finishes resuming all the devices.

Signed-off-by: Ross Lagerwall 
Signed-off-by: David Vrabel 
Signed-off-by: Greg Kroah-Hartman

xen/events/fifo: reset control block and local HEADs on resume

2014-09-17T16:19:20+00:00

commit c12784c3d14a2110468ec4d1383f60cfd2665576 upstream.

When using the FIFO-based event channel ABI, if the control block or
the local HEADs are not reset after resuming the guest may see stale
HEAD values and will fail to traverse the FIFO correctly.

This may prevent one or more VCPUs from receiving any events following
a resume.

Signed-off-by: David Vrabel 
Reviewed-by: Boris Ostrovsky 
Signed-off-by: Greg Kroah-Hartman

xen/events/fifo: ensure all bitops are properly aligned even on x86

2014-09-05T23:34:16+00:00

commit dcecb8fd93a65787130a74e61fdf29932c8d85eb upstream.

When using the FIFO-based ABI on x86_64, if the last port is at the
end of an event array page then sync_test_bit() on this port's event
word will read beyond the end of the page and in certain circumstances
this may fault.

The fault requires the following page in the kernel's direct mapping
to be not present, which would mean:

a) the array page is the last page of RAM; or

b) the following page is ballooned out /and/ it has been used for a
   foreign mapping by a kernel driver (such as netback or blkback)
   /and/ the grant has been unmapped.

Use the infrastructure added for arm64 to ensure that all bitops
operating on event words are unsigned long aligned.

Signed-off-by: David Vrabel 
Reviewed-by: Boris Ostrovsky 
Signed-off-by: Greg Kroah-Hartman

xen/balloon: set ballooned out pages as invalid in p2m

2014-07-28T15:05:57+00:00

commit fb9a0c443691ceaab3daba966bbbd9f5ff3aa26f upstream.

Since cd9151e26d31048b2b5e00fd02e110e07d2200c9 (xen/balloon: set a
mapping for ballooned out pages), a ballooned out page had its entry
in the p2m set to the MFN of one of the scratch pages.  This means
that the p2m will contain many entries pointing to the same MFN.

During a domain save, these many-to-one entries are not identified as
such and the scratch page is saved multiple times. On restore the
ballooned pages are populated with new frames and the domain may use
up its allocation before all pages can be restored.

Since the original fix only needed to keep a mapping for the ballooned
page it is safe to set ballooned out pages as INVALID_P2M_ENTRY in the
p2m (as they were before). Thus preventing them from being saved and
re-populated on restore.

Signed-off-by: David Vrabel 
Reported-by: Marek Marczykowski 
Tested-by: Marek Marczykowski 
Acked-by: Stefano Stabellini 
Signed-off-by: Greg Kroah-Hartman

xen/events/fifo: correctly align bitops

2014-05-31T20:20:29+00:00

commit 05a812ac474d0d6aef6d54b66bb08b81abde79c6 upstream.

FIFO event channels require bitops on 32-bit aligned values (the event
words).  Linux's bitops require unsigned long alignment which may be
64-bits.

On arm64 an incorrectly unaligned access will fault.

Fix this by aligning the bitops along with an adjustment for bit
position and using an unsigned long for the local copy of the ready
word.

Signed-off-by: Vladimir Murzin 
Tested-by: Pranavkumar Sawargaonkar 
Reviewed-by: Ian Campbell 
Signed-off-by: David Vrabel 
Signed-off-by: Greg Kroah-Hartman

xen/balloon: flush persistent kmaps in correct position

2014-03-25T10:38:30+00:00

Xen balloon driver will update ballooned out pages' P2M entries to point
to scratch page for PV guests. In 24f69373e2 ("xen/balloon: don't alloc
page while non-preemptible", kmap_flush_unused was moved after updating
P2M table. In that case for 32 bit PV guest we might end up with

  P2M    X -----> S  (S is mfn of balloon scratch page)
  M2P    Y -----> X  (Y is mfn in persistent kmap entry)

kmap_flush_unused() iterates through all the PTEs in the kmap address
space, using pte_to_page() to obtain the page. If the p2m and the m2p
are inconsistent the incorrect page is returned.  This will clear
page->address on the wrong page which may cause subsequent oopses if
that page is currently kmap'ed.

Move the flush back between get_page and __set_phys_to_machine to fix
this.

Signed-off-by: Wei Liu 
Signed-off-by: David Vrabel 
Cc: stable@vger.kernel.org # 3.12+

Merge tag 'stable/for-linus-3.14-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

2014-02-12T20:28:05+00:00

Pull Xen bugfixes from Konrad Rzeszutek Wilk:
 "This has an healthy amount of code being removed - which we do not use
  anymore (the only user of it was ia64 Xen which had been removed
  already).  The other bug-fixes are to make Xen ARM be able to use the
  new event channel mechanism and proper export of header files to
  user-space.

  Summary:
   - Fix ARM and Xen FIFO not working.
   - Remove more Xen ia64 vestigates.
   - Fix UAPI missing Xen files"

* tag 'stable/for-linus-3.14-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  ia64/xen: Remove Xen support for ia64 even more
  xen: install xen/gntdev.h and xen/gntalloc.h
  xen/events: bind all new interdomain events to VCPU0

ia64/xen: Remove Xen support for ia64 even more

2014-02-11T15:12:37+00:00

Commit d52eefb47d4e ("ia64/xen: Remove Xen support for ia64") removed
the Kconfig symbol XEN_XENCOMM. But it didn't remove the code depending
on that symbol. Remove that code now.

Signed-off-by: Paul Bolle 
Acked-by: David Vrabel 
Signed-off-by: Konrad Rzeszutek Wilk

xen/events: bind all new interdomain events to VCPU0

2014-02-11T15:12:34+00:00

Commit fc087e10734a4d3e40693fc099461ec1270b3fff (xen/events: remove
unnecessary init_evtchn_cpu_bindings()) causes a regression.

The kernel-side VCPU binding was not being correctly set for newly
allocated or bound interdomain events.  In ARM guests where 2-level
events were used, this would result in no interdomain events being
handled because the kernel-side VCPU masks would all be clear.

x86 guests would work because the irq affinity was set during irq
setup and this would set the correct kernel-side VCPU binding.

Fix this by properly initializing the kernel-side VCPU binding in
bind_evtchn_to_irq().

Reported-and-tested-by: Julien Grall 
Signed-off-by: David Vrabel 
Signed-off-by: Konrad Rzeszutek Wilk

Merge tag 'stable/for-linus-3.14-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

2014-02-06T00:01:11+00:00

Pull Xen fixes from Konrad Rzeszutek Wilk:
 "Bug-fixes:
   - Revert "xen/grant-table: Avoid m2p_override during mapping" as it
     broke Xen ARM build.
   - Fix CR4 not being set on AP processors in Xen PVH mode"

* tag 'stable/for-linus-3.14-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/pvh: set CR4 flags for APs
  Revert "xen/grant-table: Avoid m2p_override during mapping"