linux-toradex.git/include/xen/interface, branch v4.4.93

xen: Add RING_COPY_REQUEST()

2015-12-18T15:00:17+00:00

Using RING_GET_REQUEST() on a shared ring is easy to use incorrectly
(i.e., by not considering that the other end may alter the data in the
shared ring while it is being inspected).  Safe usage of a request
generally requires taking a local copy.

Provide a RING_COPY_REQUEST() macro to use instead of
RING_GET_REQUEST() and an open-coded memcpy().  This takes care of
ensuring that the copy is done correctly regardless of any possible
compiler optimizations.

Use a volatile source to prevent the compiler from reordering or
omitting the copy.

This is part of XSA155.

CC: stable@vger.kernel.org
Signed-off-by: David Vrabel 
Signed-off-by: Konrad Rzeszutek Wilk

x86/xen: Support kexec/kdump in HVM guests by doing a soft reset

2015-09-28T13:48:52+00:00

Currently there is a number of issues preventing PVHVM Xen guests from
doing successful kexec/kdump:

  - Bound event channels.
  - Registered vcpu_info.
  - PIRQ/emuirq mappings.
  - shared_info frame after XENMAPSPACE_shared_info operation.
  - Active grant mappings.

Basically, newly booted kernel stumbles upon already set up Xen
interfaces and there is no way to reestablish them. In Xen-4.7 a new
feature called 'soft reset' is coming. A guest performing kexec/kdump
operation is supposed to call SCHEDOP_shutdown hypercall with
SHUTDOWN_soft_reset reason before jumping to new kernel. Hypervisor
(with some help from toolstack) will do full domain cleanup (but
keeping its memory and vCPU contexts intact) returning the guest to
the state it had when it was first booted and thus allowing it to
start over.

Doing SHUTDOWN_soft_reset on Xen hypervisors which don't support it is
probably OK as by default all unknown shutdown reasons cause domain
destroy with a message in toolstack log: 'Unknown shutdown reason code
5. Destroying domain.'  which gives a clue to what the problem is and
eliminates false expectations.

Signed-off-by: Vitaly Kuznetsov 
Cc: 
Signed-off-by: David Vrabel

Merge tag 'for-linus-4.3-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

2015-09-08T18:46:48+00:00

Pull xen updates from David Vrabel:
 "Xen features and fixes for 4.3:

   - Convert xen-blkfront to the multiqueue API
   - [arm] Support binding event channels to different VCPUs.
   - [x86] Support > 512 GiB in a PV guests (off by default as such a
     guest cannot be migrated with the current toolstack).
   - [x86] PMU support for PV dom0 (limited support for using perf with
     Xen and other guests)"

* tag 'for-linus-4.3-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (33 commits)
  xen: switch extra memory accounting to use pfns
  xen: limit memory to architectural maximum
  xen: avoid another early crash of memory limited dom0
  xen: avoid early crash of memory limited dom0
  arm/xen: Remove helpers which are PV specific
  xen/x86: Don't try to set PCE bit in CR4
  xen/PMU: PMU emulation code
  xen/PMU: Intercept PMU-related MSR and APIC accesses
  xen/PMU: Describe vendor-specific PMU registers
  xen/PMU: Initialization code for Xen PMU
  xen/PMU: Sysfs interface for setting Xen PMU mode
  xen: xensyms support
  xen: remove no longer needed p2m.h
  xen: allow more than 512 GB of RAM for 64 bit pv-domains
  xen: move p2m list if conflicting with e820 map
  xen: add explicit memblock_reserve() calls for special pages
  mm: provide early_memremap_ro to establish read-only mapping
  xen: check for initrd conflicting with e820 map
  xen: check pre-allocated page tables for conflict with memory map
  xen: check for kernel memory conflicting with memory layout
  ...

xen-netback: add support for multicast control

2015-09-02T18:45:00+00:00

Xen's PV network protocol includes messages to add/remove ethernet
multicast addresses to/from a filter list in the backend. This allows
the frontend to request the backend only forward multicast packets
which are of interest thus preventing unnecessary noise on the shared
ring.

The canonical netif header in git://xenbits.xen.org/xen.git specifies
the message format (two more XEN_NETIF_EXTRA_TYPEs) so the minimal
necessary changes have been pulled into include/xen/interface/io/netif.h.

To prevent the frontend from extending the multicast filter list
arbitrarily a limit (XEN_NETBK_MCAST_MAX) has been set to 64 entries.
This limit is not specified by the protocol and so may change in future.
If the limit is reached then the next XEN_NETIF_EXTRA_TYPE_MCAST_ADD
sent by the frontend will be failed with NETIF_RSP_ERROR.

Signed-off-by: Paul Durrant 
Cc: Ian Campbell 
Cc: Wei Liu 
Acked-by: Wei Liu 
Signed-off-by: David S. Miller

xen/PMU: Intercept PMU-related MSR and APIC accesses

2015-08-20T11:25:25+00:00

Provide interfaces for recognizing accesses to PMU-related MSRs and
LVTPC APIC and process these accesses in Xen PMU code.

(The interrupt handler performs XENPMU_flush right away in the beginning
since no PMU emulation is available. It will be added with a later patch).

Signed-off-by: Boris Ostrovsky 
Reviewed-by: David Vrabel 
Signed-off-by: David Vrabel

xen/PMU: Initialization code for Xen PMU

2015-08-20T11:25:20+00:00

Map shared data structure that will hold CPU registers, VPMU context,
V/PCPU IDs of the CPU interrupted by PMU interrupt. Hypervisor fills
this information in its handler and passes it to the guest for further
processing.

Set up PMU VIRQ.

Now that perf infrastructure will assume that PMU is available on a PV
guest we need to be careful and make sure that accesses via RDPMC
instruction don't cause fatal traps by the hypervisor. Provide a nop
RDPMC handler.

For the same reason avoid issuing a warning on a write to APIC's LVTPC.

Both of these will be made functional in later patches.

Signed-off-by: Boris Ostrovsky 
Reviewed-by: David Vrabel 
Signed-off-by: David Vrabel

xen/PMU: Sysfs interface for setting Xen PMU mode

2015-08-20T11:24:26+00:00

Set Xen's PMU mode via /sys/hypervisor/pmu/pmu_mode. Add XENPMU hypercall.

Signed-off-by: Boris Ostrovsky 
Reviewed-by: Konrad Rzeszutek Wilk 
Signed-off-by: David Vrabel

xen: xensyms support

2015-08-20T11:24:25+00:00

Export Xen symbols to dom0 via /proc/xen/xensyms (similar to
/proc/kallsyms).

Signed-off-by: Boris Ostrovsky 
Reviewed-by: David Vrabel 
Signed-off-by: David Vrabel

xen: sync with xen headers

2015-08-20T11:24:16+00:00

Use the newest headers from the xen tree to get some new structure
layouts.

Signed-off-by: Juergen Gross 
Reviewed-by: David Vrabel 
Acked-by: Konrad Rzeszutek Wilk 
Signed-off-by: David Vrabel

xen: synchronize include/xen/interface/xen.h with xen

2015-03-16T14:49:13+00:00

The header include/xen/interface/xen.h doesn't contain all definitions
from Xen's version of that header. Update it accordingly.

Signed-off-by: Juergen Gross 
Reviewed-by: David Vrabel 
Signed-off-by: David Vrabel