This allows migration to a host with less MCA banks than the source
host had, while without this patch accesses to the excess banks' MSRs
caused #GP-s in the guest after migration (and it depended on the guest
kernel whether this would be fatal).
A fundamental question is whether we should also save/restore MCG_CTL
and MCi_CTL, as the HVM save record would better be defined to the
complete state that needs saving from the beginning (I'm unsure whether
the save/restore logic allows for future extension of an existing
record).
Of course, this change is expected to make migration from new to older
Xen impossible (again I'm unsure what the save/restore logic does with
records it doesn't even know about).
The (trivial) tools side change may seem unrelated, but the code should
have been that way from the beginning to allow the hypervisor to look
at currently unused ext_vcpucontext fields without risking to read
garbage when those fields get a meaning assigned in the future. This
isn't being enforced here - should it be? (Obviously, for backwards
compatibility, the hypervisor must assume these fields to be clear only
when the extended context's size exceeds the old original one.)
A future addition to this change might be to allow configuration of the
number of banks and other MCA capabilities for a guest before it starts
(i.e. to not inherits the values seen on the first host it runs on).
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Keir Fraser <keir@xen.org>
NetBSD libxc hypercall implementation was returning -errno on error,
instead of the actual error value from ioctl. Returning error is
easier to understand, and the caller can always check errno.
Signed-off-by: Roger Pau Monne <roger.pau@entel.upc.edu>
Acked-by: Ian Campbell <ian.campbell.com>
Committed-by: Ian Jackson <ian.jackson.citrix.com>
Reported-by: Olaf Hering <olaf@aepfle.de>
Added a comment that explains why NetBSD return hypercall->retval on
success.
Signed-off-by: Roger Pau Monne <roger.pau@entel.upc.edu>
Acked-by: Ian Campbell <ian.campbell.com>
Committed-by: Ian Jackson <ian.jackson.citrix.com>
Reported-by: Olaf Hering <olaf@aepfle.de>
Remove costly mem_sharing audits from the inline path, and instead make them
callable as a memop.
Have the audit function return the number of errors detected.
Update memshrtool to be able to trigger audits.
Set sharing audits as enabled by default.
Signed-off-by: Andres Lagar-Cavilla <andres@lagarcavilla.org>
Signed-off-by: Adin Scannell <adin@scannell.ca>
Acked-by: Tim Deegan <tim@xen.org>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Committed-by: Tim Deegan <tim@xen.org>
Per page operations in the paging, sharing, and access tracking subsystems are
all implemented with domctls (e.g. a domctl to evict one page, or to share one
page).
Under heavy load, the domctl path reveals a lack of scalability. The domctl
lock serializes dom0's vcpus in the hypervisor. When performing thousands of
per-page operations on dozens of domains, these vcpus will spin in the
hypervisor. Beyond the aggressive locking, an added inefficiency of blocking
vcpus in the domctl lock is that dom0 is prevented from re-scheduling any of
its other work-starved processes.
We retain the domctl interface for setting up and tearing down
paging/sharing/mem access for a domain. But we migrate all the per page
operations to use the memory_op hypercalls (e.g XENMEM_*).
Signed-off-by: Andres Lagar-Cavilla <andres@lagarcavilla>
Signed-off-by: Adin Scannell <adin@scannell.ca>
Acked-by: Tim Deegan <tim@xen.org>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Committed-by: Tim Deegan <tim@xen.org>
In some cases guests should not provide workarounds for errata even when the
physical processor is affected. For example, because of erratum 400 on family
10h processors a Linux guest will read an MSR (resulting in VMEXIT) before
going to idle in order to avoid getting stuck in a non-C0 state. This is not
necessary: HLT and IO instructions are intercepted and therefore there is no
reason for erratum 400 workaround in the guest.
This patch allows us to present a guest with certain errata as fixed,
regardless of the state of actual hardware.
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@amd.com>
Acked-by: Christoph Egger <Christoph.Egger@amd.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Keir Fraser <keir@xen.org>
Committed-by: Jan Beulich <jbeulich@suse.com>
Instead of placing string parsing inside the hypervisor, use binary
structures like other Xen hypercalls do.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Committed-by: Keir Fraser <keir@xen.org>
This library has been deprecated since July 2010; remove the in-tree
users and library.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Committed-by: Keir Fraser <keir@xen.org>
All bitmaps maintained by xc_bitops.h are used in single threaded
applications. So nothing will change the bitmaps content, adding
volatile adds just unneeded memory reloads.
xenpaging uses bitmaps alot and using non-volatile versions will
slightly improve performance.
Signed-off-by: Olaf Hering <olaf@aepfle.de>
Committed-by: Keir Fraser <keir@xen.org>
Changeset 23577:607474aeefe1 introduced an error in
xc_ia64_send_vcpumap(), bitmap_alloc() was not used correctly.
Signed-off-by: Olaf Hering <olaf@aepfle.de>
Committed-by: Keir Fraser <keir@xen.org>
mlock and munlock are implemented as macros in mini-os. Their usage
requires casting in common code. Convert them to C syntax and provide
an empty dummy function. Remove the now unneeded (void) cast from two
munlock calls.
Signed-off-by: Olaf Hering <olaf@aepfle.de>
This patch sends global VIRQs to a domain designated as the VIRQ
handler
instead of sending all global VIRQ events to dom0. This is required in
order to run xenstored in a stubdom, because VIRQ_DOM_EXC must be sent
to xenstored for domain destruction to work properly.
This patch was inspired by the xenstored stubdomain patch series sent
to xen-devel by Alex Zeffertt in 2009.
Signed-off-by: Diego Ongaro <diego.ongaro@citrix.com>
Signed-off-by: Alex Zeffertt <alex.zeffertt@eu.citrix.com>
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Committed-by: Keir Fraser <keir@xen.org>
If the first ioctl fails with ENOENT it means the command is known. If a
second attempt to map each gfn happens to fail then there is no need to
run the fallback code. Some gfns are paged and the fallback code would
not fix the failure. Instead return the EINVAL to the caller.
Signed-off-by: Olaf Hering <olaf@aepfle.de>
Acked-by: Andres Lagar-Cavilla <andres@lagarcavilla.org>
Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>
Bring xc_mem_paging.c in line with other users of munlock in libxc.
Otherwise it trips over -Werror=unused-value
Signed-off-by: Tim Deegan <tim@xen.org>
This patch is the folded version of API updates, along with the associated tool
changes to ensure that the build is always consistent.
API updates:
- The source domain in the sharing calls is no longer assumed to be dom0.
- Previously, the mem sharing code would return an opaque handle to index
shared pages (and nominees) in its global hash table. By removing the hash
table, the handle becomes a version, to avoid sharing a stale version of a
page. Thus, libxc wrappers and tools need to be updated to recall the share
functions with the information needed to fetch the page (which they readily
have).
Tool updates:
The only (in-tree, that we know of) consumer of the mem sharing API is the
memshr tool. This is updated to use the new API.
Signed-off-by: Andres Lagar-Cavilla <andres@lagarcavilla.org>
Signed-off-by: Adin Scannell <adin@scannell.ca>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Committed-by: Tim Deegan <tim@xen.org>
xc_mem_paging_load() does not pass errors in errno and the actual
errno from xc_mem_event_control() is overwritten by munlock().
xenpaging_populate_page() needs to check errno, but with the switch to
xc_mem_paging_load() it could not receive ENOMEM anymore.
Update xc_mem_paging_load() to return -1 and preserve errno during
munlock().
Signed-off-by: Olaf Hering <olaf@aepfle.de>
Acked-by: Andres Lagar-Cavilla <andres@lagarcavilla.org>
Committed-by: Keir Fraser <keir@xen.org>
Implement a new function, called elf_load_image, to perform the
actually copy of the elf image and clearing the padding. The function
is implemented as memcpy and memset when the library is built as part
of the tools, but it is implemented as raw_copy_to_guest and
raw_clear_guest when built as part of Xen, so that it can be safely
called with an HVM style dom0.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Tim Deegan <Tim.Deegan@citrix.com>
Committed-by: Keir Fraser <keir@xen.org>
Add code to track the address of the VM generation ID buffer across a
save/restore or migrate, and increment it as necessary.
The address of the buffer is written into xenstore by hvmloader at
boot time. It must be read from xenstore by the caller of
xc_domain_save() and then written back again by the caller of
xc_domain_restore().
Note that the changes to xc_save.c and xc_restore.c are merely
sufficient for them to build.
Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Committed-by: Ian Jackson <ian.jackson.citrix.com>
Currently the memshr functions use uint32_t for the domid. This actually leads
to a funny domid_t -> uint32_t -> domid_t sequence of casts. This patch
updates the API functions to be domid_t in the first place.
No tools need to be modified with this patch, the casts were implicit.
Signed-off-by: Adin Scannell <adin@scannell.ca>
Signed-off-by: Andres Lagar-Cavilla <andres@lagarcavilla.org>
Acked-by: Ian Jackson <ian.jackson.citrix.com>
Committed-by: Ian Jackson <ian.jackson.citrix.com>
If the return value from the ioctl() is not ENOENT, it's possible that err[i]
will not be updated and libxc will just loop forever. Although it's unlikely
that err[i] would not be updated after the ioctl() gets through at least once,
it's better to be defensive.
Signed-off-by: Adin Scannell <adin@scannell.ca>
Signed-off-by: Andres Lagar-Cavilla <andres@lagarcavilla.org>
Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>
This patch is used to prepare exposing PCID/INVPCID features to hvm
guest.
The specific exposure result depend on hvm paging mode (hap/shadow),
which would be handled at next patch.
Signed-off-by: Liu, Jinsong <jinsong.liu@intel.com>
Committed-by: Keir Fraser <keir@xen.org>
Pushing stuff onto the stack on x86-64 when we do not specify
-mno-red-zone is unsafe. Since the complicated asm is due to register
pressure on i386, we simply implement an all-new simpler alternative
for x86-64.
Signed-off-by: Keir Fraser <keir@xen.org>
Acked-by: Jan Beulich <jbeulich@novell.com>
It's not really any more useful than explicitly setting new M2P
entries to the invalid value.
Signed-off-by: Tim Deegan <tim@xen.org>
Committed-by: Keir Fraser <keir@xen.org>
The notify offset and event channels are both unsigned variables, so
testing for >= 0 will not correctly detect the use of -1 to indicate
the field is unused. Remove the useless comparison and replace with
correct range checks or comparisons to -1.
Reported-by: Anil Madhavapeddy <anil@recoil.org>
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>
Instead of sending dirty pages of guest memory as-is, use a simple compression
algorithm that sends a RLE-encoded XOR of the page against its last sent copy.
A small LRU cache is used to hold recently dirtied pages. Pagetable pages are
sent as-is, as they are canonicalized at sender side and uncanonicalized at
receiver.
[ Fixed up a conflict in sg_save_restore.h. I had to increase the
ID values used from -11 and -12 to -12 and -13 because -11 had
been taken by ..._HVM_VIRIDIAN in the meantime. -iwj ]
Signed-off-by: Shriram Rajagopalan <rshriram@cs.ubc.ca>
Acked-by: Brendan Cully <brendan@cs.ubc.ca>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>
Move (page aligned) buffer allocations in {os}_privcmd_alloc_hypercall_buffer
into a global function xc_memalign. This API is also used by Remus
compression code to allocate compression caches that need to be page aligned.
Signed-off-by: Shriram Rajagopalan <rshriram@cs.ubc.ca>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Brendan Cully <brendan@cs.ubc.ca>
Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>
This is due to a stale check for guest_handle_null in the hypervisor,
which doesn't necessarily work with the hypercall buffers.
Signed-off-by: Andres Lagar-Cavilla <andres@lagarcavilla.org>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Committed-by: Tim Deegan <tim@xen.org>
xc_domain_save/restore currently pay no attention to
HVM_PARAM_VIRIDIAN which results in an HVM domain running a recent
version on Windows (post-Vista) locking up on a domain restore due to
EOIs (done via a viridian MSR write) being silently dropped. This
patch adds an extra save entry for the viridian parameter and also
adds code in the viridian kernel module to catch attempted use of
viridian functionality when the HVM parameter has not been set.
Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Committed-by: Keir Fraser <keir@xen.org>
Since hvmloader has a xentore client, use a platform key in xenstore
to indicate whether ACPI is enabled or not rather than the shared
hvm_info_table structure.
Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Committed-by: Keir Fraser <keir@xen.org>
The layouts were actually correct, but the type names were a bit
messed up.
Original patch by Volker Eckert <volker.eckert@citrix.com>
Signed-off-by: Keir Fraser <keir@xen.org>
Create two new variables called APPEND_ and PREPEND_ to add compile
flags at the beginning or at the end of the search path.
Added a new semantic for user defined compile flags, here is the list
of possible options:
PREPEND_LIB: add libraries to the search path before xen
(before xen installation folders).
PREPEND_INCLUDES: add headers to the search path before xen
(before xen installation folders).
APPEND_LIB: add libraries to the search path at the end
(after all xen installation folders have been added).
APPEND_INCLUDES: add libraries to the search path at the end
(after all xen installation folders have been added).
EXTRA_INCLUDES and EXTRA_LIB can still be used, and they will have the
same effect as PREPEND_INCLUDES and PREPEND_LIB.
Signed-off-by: Roger Pau Monne <roger.pau@entel.upc.edu>
Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>
Provide pse36 cpuid bit if guest runs in 32bit PAE
or in long mode. Hyper-V refuses to start as
the "cpu does not provide required hw features"
if it does not find the pse36 cpuid bits.
Signed-off-by: Christoph Egger <Christoph.Egger@amd.com>
Acked-by: Tim Deegan <tim@xen.org>
Committed-by: Tim Deegan <tim@xen.org>
Sandy bridge introduces new MSR to get cc7/pc2 residency (core C-state
7/package C-state 2). Print the cc7/pc2 residency when on sandy bridge
platform.
Signed-off-by: Yang Zhang <yang.z.zhang@intel.com>
Committed-by: Keir Fraser <keir@xen.org>
Backends were inconsistent about reporting and it's a pain to edit them all
when adding a new class of osdep.
Signed-off-by: Ian Campbell <Ian.campbell@citrix.com>
Acked-by: Ian Jackson <ian.jackson.citrix.com>
Committed-by: Ian Jackson <ian.jackson.citrix.com>
---
Requires Daniel De Graaf's "libxc: add xc_gntshr_* functions"
These functions and the xc_gntshr device (/dev/xen/gntalloc on linux)
allow applications to create pages shared with other domains.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>
Normally, when a userspace process mapping a grant crashes, the domain
providing the reference receives no indication that its peer has
crashed, possibly leading to unexpected freezes or timeouts. This
function provides a notification of the unmap by signalling an event
channel and/or clearing a specific byte in the page.
This also unifies the 3 very similar grant-mapping osdep interfaces into
a single function instead of introducing yet another minor variation.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
The toolstack should know how many pages are paged-out at a given point
in time so it could make smarter decisions about how many pages should
be paged or ballooned.
Add a new member to xen_domctl_getdomaininfo and bump interface version.
Use the new member in xc_dominfo_t.
The SONAME of libxc should be changed if this patch gets applied.
Signed-off-by: Olaf Hering <olaf@aepfle.de>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Tim Deegan <tim@xen.org>
Committed-by: Tim Deegan <tim@xen.org>
Jan Beulich
George Dunlap
David Vrabel
Roger Pau Monne
Andres Lagar-Cavilla
Alex Zeffertt
Santosh Jodh
Boris Ostrovsky
Daniel De Graaf
Olaf Hering
Tim Deegan
Stefano Stabellini
Keir Fraser
Paul Durrant
Liu, Jinsong
Shriram Rajagopalan
Yang Zhang
Ian Campbell
Olaf Hering