CMPXCHG sets CF, PF, AF, SF, and OF flags according to the results of the
comparison the rAX with the operand of the instruction.
rAX must be the first argument of the comparison (a minuend), the operand
must be the second one (a subtrahend).
Due to improper order of comparison arguments, CF, PF, AF, SF and OF flags were
set incorrectly in the case of inequality. Need to swap them.
Signed-off-by: Eugene Korenevsky <ekorenevsky@gmail.com>
test_x86_emulate: extend EFLAGS check of CMPXCHG test
CMPXCHG: in the case of inequality of the rAX and the operand,
need to check CF, PF, AF, SF and OF flags as well.
This adjustment covers the fix of incorrect comparison during
CMPXCHG emulation.
Signed-off-by: Eugene Korenevsky <ekorenevsky@gmail.com>
master commit: 2232628ecb
master date: 2015-05-04 11:55:41 +0200
master commit: 20fd4b70a7
master date: 2015-05-04 12:03:19 +0200
Some EFI firmware implementations may place the SMBIOS table in RAM
marked as BootServicesData, which Xen does not consider as reserved.
When dom0 tries to access the SMBIOS, the region is not contained in the
initial P2M and it crashes with a page fault. To fix this, reserve the
SMBIOS region.
Also, fix the memcmp checks for existence of the SMBIOS.
Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
master commit: bf68adcada
master date: 2015-04-17 10:44:48 +0200
With ->startup unmasking the IRQ, setting the affinity afterwards
without masking the IRQ again is invalid namely for MSI (address and
data can't be updated atomically and may - at least for MSI-X - be
cached while unmasked).
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
AMD IOMMU: only translate remapped IO-APIC RTEs
1aeb1156fa ("x86 don't change affinity with interrupt unmasked")
introducing RTE reads prior to the respective interrupt having got
enabled for the first time uncovered a bug in 2ca9fbd739 ("AMD IOMMU:
allocate IRTE entries instead of using a static mapping"): We obviously
shouldn't be translating RTEs for which remapping didn't get set up
yet.
Reported-by: Sander Eikelenboom <linux@eikelenboom.it>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
master commit: 1aeb1156fa
master date: 2015-03-26 11:18:28 +0100
master commit: c33c51b81c
master date: 2015-04-24 12:06:26 +0200
In the hopes of making any future errors along the lines of XSA-123
into clean crashes instead of memory corruption bugs.
Signed-off-by: Tim Deegan <tim@xen.org>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: dd766684e7
master date: 2015-03-27 16:13:07 +0100
I got repeatedly annoyed by there not getting anything logged by
default on VT-d faults (and hence having to tell people to add extra
command line options), and hence I think it is time to redo this code:
Log basic fault information at guest-warning level (rate limited by
default), and show the page walk in verbose rather than only in debug
mode. Break up multi-line message so that each gets a proper log level
attached, at once splitting out the common part. Also don't log
"unknown" faults as interrupt-remapping ones.
As a minor cleanup fix the type of the involved "fault_type" variables.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Yang Zhang <yang.z.zhang@intel.com>
master commit: f0250f4b48
master date: 2015-03-27 15:23:25 +0100
__setup_msi_irq() needs to undo what it did before calling
write_msi_msg() in case that returned an error.
map_domain_pirq() needs to get rid of the MSI descriptor it
(implicitly) allocated. The case of a setup_msi_irq() failure on a
non-initial multi-vector-MSI interrupt needs special handling: While
the initial IRQ will get freed by the caller (who also passed it to
us), we need to undo the effect setup_msi_irq() had on it. (As a
benefit from the added call to msi_free_irq() we no longer need to
explicitly call destroy_irq() on the non-initial slots.)
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 29c1b7886c
master date: 2015-03-26 11:19:57 +0100
If the part of the compression data are corrupted, or the compression
data is totally fake, the memory access over the limit is possible.
This is the log from my system usning lz4 decompression.
[6502]data abort, halting
[6503]r0 0x00000000 r1 0x00000000 r2 0xdcea0ffc r3 0xdcea0ffc
[6509]r4 0xb9ab0bfd r5 0xdcea0ffc r6 0xdcea0ff8 r7 0xdce80000
[6515]r8 0x00000000 r9 0x00000000 r10 0x00000000 r11 0xb9a98000
[6522]r12 0xdcea1000 usp 0x00000000 ulr 0x00000000 pc 0x820149bc
[6528]spsr 0x400001f3
and the memory addresses of some variables at the moment are
ref:0xdcea0ffc, op:0xdcea0ffc, oend:0xdcea1000
As you can see, COPYLENGH is 8bytes, so @ref and @op can access the momory
over @oend.
Signed-off-by: JeHyeon Yeon <tom.yeon@windriver.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
[Linux commit d5e7cafd69da24e6d6cc988fab6ea313a2577efc]
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
master commit: fcc17f96c2
master date: 2015-03-26 11:19:10 +0100
These DOMCTL subops were accidentally declared safe for disaggregation
in the wake of XSA-77.
This is XSA-127 / CVE-2015-2751.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Said hypercall for large BARs can take quite a while. As such
we can require that the hypercall MUST break up the request
in smaller values.
Another approach is to add preemption to it - whether we do the
preemption using hypercall_create_continuation or returning
EAGAIN to userspace (and have it re-invocate the call) - either
way the issue we cannot easily solve is that in 'map_mmio_regions'
if we encounter an error we MUST call 'unmap_mmio_regions' for the
whole BAR region.
Since the preemption would re-use input fields such as nr_mfns,
first_gfn, first_mfn - we would lose the original values -
and only undo what was done in the current round (i.e. ignoring
anything that was done prior to earlier preemptions).
Unless we re-used the return value as 'EAGAIN|nr_mfns_done<<10' but
that puts a limit (since the return value is a long) on the amount
of nr_mfns that can provided.
This patch sidesteps this problem by:
- Setting an hard limit of nr_mfns having to be 64 or less.
- Toolstack adjusts correspondingly to the nr_mfn limit.
- If the there is an error when adding the toolstack will call the
remove operation to remove the whole region.
The need to break this hypercall down is for large BARs can take
more than the guest (initial domain usually) time-slice. This has
the negative result in that the guest is locked out for a long
duration and is unable to act on any pending events.
We also augment the code to return zero if nr_mfns instead
of trying to the hypercall.
This is XSA-125 / CVE-2015-2752.
Suggested-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
If reboot= is specified on the command-line, don't apply reboot quirks
to allow the command-line option to take precedence.
This is a port of Linux commit 5955633e91bf ("x86/reboot: Skip DMI
checks if reboot set by user").
Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Leverage (and make apply on top of) c643fb110a ("x86/EFI: allow
reboot= overrides when running under EFI").
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 9832f5e8e3
master date: 2015-03-13 12:41:51 +0100
This reverts commit 93be8285a7.
At the point this patch calls domain_update_node_affinity(), the vcpu
hard affinities have not yet been updated; so calling it at this point
can in some circumstances trigger an ASSERT().
domain_update_node_affinity() is already called in
cpu_disable_scheduler(), so adding it to cpupool_unassign_cpu() is
redundant. Simply reverting the patch is sufficient.
Acked-by: George Dunlap <george.dunlap@eu.citrix.com>
By default we will always use EFI reboot mechanism when
running under EFI platforms. However some EFI platforms
are buggy and need to use the ACPI mechanism to
reboot (such as Lenovo ThinkCentre M57). As such
respect the 'reboot=' override and DMI overrides
for EFI platforms.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
- BOOT_INVALID is just zero
- also consider acpi_disabled in BOOT_INVALID resolution
- duplicate BOOT_INVALID resolution in machine_restart()
- don't fall back from BOOT_ACPI to BOOT_EFI (if it was overridden, it
surely was for a reason)
- adjust doc change formatting
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
x86/EFI: fix reboot after c643fb110a
acpi_disabled needs to be moved out of .init.data.
Reported-by: Ross Lagerwall <ross.lagerwall@citrix.com>
From: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Tested-by: Ross Lagerwall <ross.lagerwall@citrix.com>
master commit: c643fb110a
master date: 2015-03-13 11:25:52 +0100
master commit: 8ff330ec11
master date: 2015-03-23 18:01:51 +0100
Copy the entire output buffer to the guest because some firmwares update
size on successful calls (contrary to the spec) and the buffer may
contain data beyond the output size that the firmware requires on a
subsequent GetNextVariableName() call (e.g. a NULL character).
Note that this shouldn't change the amount of data copied because on success, a
compliant firmware does not change size and so the entire buffer is copied
anyway. If size is changed, Xen does not copy the buffer.
Without this change, the following (simplified) sequence would occur:
GetNextVariableName: in \0, size 1024 || out AdminPw\0, size 7
GetNextVariableName: in AdminPw\0, size 1024 || out UserPw\0, size 6
GetNextVariableName: in UserPww\0, size 1024 || NOT FOUND
This was seen on an Intel S1200RP_SE with firmware
S1200RP.86B.02.02.0005.102320140911, version 4.6, date 2014-10-23.
Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 1f4eb9d27d
master date: 2015-03-10 13:52:01 +0100
Even if VT-d code alone (i.e. when not sharing tables with EPT) still
doesn't support superpages, this function - invoked upon DMA remapping
faults - needs to cope with such.
While at it also replace a few more plain numbers with suitable named
constants.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Kevin Tian <kevin.tian@intel.com>
master commit: 92cf6c2456
master date: 2015-03-09 14:00:19 +0100
Non-anonymous allocations with this flag set should - for the purpose
of the availability check - be treated just like anonymous ones, as
they wouldn't lead to a reduction of ->outstanding_pages.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Tim Deegan <tim@xen.org>
master commit: 17294e69c4
master date: 2015-02-26 13:58:54 +0100
The implementation was backwards and checked that the guest could
read when asked about write and vice versa.
This is an update to the fix for XSA-98.
Reported-by: Tamas K Lengyel <tklengyel@sec.in.tum.de>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
(cherry picked from commit c1245e9d5b)
By default qemu will try to create some sort of backend for the
emulated VGA device, either SDL or VNC.
However when the user specifies sdl=0 and vnc=0 in their configuration
libxl was not explicitly disabling either backend, which could lead to
one unexpectedly running.
If either sdl=1 or vnc=1 is configured then both before and after this
change only the backends which are explicitly enabled are configured,
i.e. this issue only occurs when all backends are supposed to have
been disabled.
This affects qemu-xen and qemu-xen-traditional differently.
If qemu-xen was compiled with SDL support then this would result in an
SDL window being opened if $DISPLAY is valid, or a failure to start
the guest if not. Passing "-display none" to qemu before any further
-sdl options disables this default behaviour and ensures that SDL is
only started if the libxl configuration demands it.
If qemu-xen was compiled without SDL support then qemu would instead
start a VNC server listening on ::1 (IPv6 localhost) or 127.0.0.1
(IPv4 localhost) with IPv6 preferred if available. Explicitly pass
"-vnc none" when vnc is not enabled in the libxl configuration to
remove this possibility.
qemu-xen-traditional would never start a vnc backend unless asked.
However by default it will start an SDL backend, the way to disable
this is to pass a -vnc option. In other words passing "-vnc none" will
disable both vnc and sdl by default. sdl can then be reenabled if
configured by subsequent use of the -sdl option.
Tested with both qemu-xen and qemu-xen-traditional built with SDL
support and:
xl cr # defaults
xl cr sdl=0 vnc=0
xl cr sdl=1 vnc=0
xl cr sdl=0 vnc=1
xl cr sdl=0 vnc=0 vga=\"none\"
xl cr sdl=0 vnc=0 nographic=1
with both valid and invalid $DISPLAY.
This is XSA-119 / CVE-2015-2152.
Reported-by: Sander Eikelenboom <linux@eikelenboom.it>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
(cherry picked from commit 91b0ae9db3)
(cherry picked from commit 6616c4d6fe)
In order for commit cbeeaa7d ("x86/nmi: fix shootdown of pcpus
running in VMX non-root mode")'s re-use of that fixmap entry to not
cause undesirable (in crash context) cross-CPU TLB flushes, invalidate
the fixmap entry right after use.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
master commit: 375a09cffa
master date: 2015-03-04 09:59:47 +0100
For ModRM encoded instructions with register operands we must not
overwrite ea.mem.seg (if a - bogus in that case - segment override was
present) as it aliases with ea.reg.
This is CVE-2015-2151 / XSA-123.
Reported-by: Felix Wilhelm <fwilhelm@ernw.de>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Tim Deegan <tim@xen.org>
Reviewed-by: Keir Fraser <keir@xen.org>
master commit: bcf92a5382
master date: 2015-03-10 13:45:51 +0100
... avoiding to pass hypervisor stack contents back to the caller
through space unused by the respective strings.
This is CVE-2015-2045 / XSA-122.
Signed-off-by: Aaron Adams <Aaron.Adams@nccgroup.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
master commit: fe2e079f64
master date: 2015-03-05 13:35:54 +0100
So far the value presented to the guest remained uninitialized.
This is CVE-2015-2044 / XSA-121.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
master commit: c9e57594e1
master date: 2015-03-05 13:34:54 +0100
c/s d1b93ea causes substantial functional regressions in pygrub's ability to
parse bootloader configuration files.
c/s d1b93ea itself changed an an interface which previously used exclusively
integers, to using strings in the case of a grub configuration with explicit
default set, along with changing the code calling the interface to require a
string. The default value for "default" remained as an integer.
As a result, any Extlinux or Lilo configuration (which drives this interface
exclusively with integers), or Grub configuration which doesn't explicitly
declare a default will die with an AttributeError when attempting to call
"self.cf.default.isdigit()" where "default" is an integer.
Sadly, this AttributeError gets swallowed by the blanket ignore in the loop
which searches partitions for valid bootloader configurations, causing the
issue to be reported as "Unable to find partition containing kernel"
We should explicitly check type of "default" in image_index() and process it
appropriately.
Reported-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
(cherry picked from commit 3b27981170)
Changes to handle non-numeric default attributes for grub2 caused run_grub()
to attempt to index into the images list using a string. Pull out the code
that handles submenus into a new function and use that to ensure sel is
numeric.
Reported-by: David Scott <dave.scott@citrix.com>
Signed-off-by: Simon Rowe <simon.rowe@eu.citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-and-tested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
(cherry picked from commit 4ee393f9d6)
Currently pygrub can only correctly parse grub2's default attribute when it is
specified as a number. If it is set to ${saved_entry} or ${next_entry} then
the first image (i.e. entry number 0) is selected. If any other value is
specified (typically this would be the string in menuentry) pygrub will crash.
This patch will allow pygrub to interpret default attribute if it is specified
as a string (note that in case of submenus only the leaf string will be
considered).
Also issue a warning if default is set to ${saved_entry} or ${next_entry}.
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
(cherry picked from commit d1b93ea261)
c/s 7dd3b06ff "vmx: fix handling of NMI VMEXIT" fixed one issue but
inadvertently introduced a regression when it came to the NMI shootdown. The
shootdown code worked by patching vector 2 in each IDT, but the introduced
direct call to do_nmi() bypassed this.
Instead of patching each IDT, take a different approach by updating the
existing dispatch table. This allows for the removal of the remote IDT
patching and the removal of the nmi_crash() entry point.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
master commit: cbeeaa7da0
master date: 2015-02-11 17:18:27 +0100
and use it in preference to the direct call to do_nmi() in vmx.c
The value 'TRAP_last_reserved' was only used where 'TRAP_nr' would be more
appropriate, so is replaced.
No functional change
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
master commit: d3eb16b8a7
master date: 2015-02-11 17:16:18 +0100
NMI watchdog sets APIC_LVTPC register to generate an NMI when PMU counter
overflow occurs. This may be overwritten by VPMU code later, effectively
turning off the watchdog.
We should disable VPMU when NMI watchdog is running.
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: e5e09b5c46
master date: 2015-02-03 11:30:09 +0100
"origPtr" is used as an offset into the bd->dbuf[] array. That array is
allocated in start_bunzip() and has "bd->dbufSize" number of elements so
the test here should be >= instead of >.
Later we check "origPtr" again before using it as an offset so I don't
know if this bug can be triggered in real life.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Trivial adjustments to make the respective Linux commit
b5c8afe5be51078a979d86ae5ae78c4ac948063d apply to Xen.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
master commit: 39798e95a9
master date: 2015-01-28 16:50:08 +0100
.. otherwise it has the side effect that: domain_relinquish_resources
will stop and will return to user-space with -EINTR which it is not
equipped to deal with that error code; or vcpu_reset - which will
ignore it and convert the error to -ENOMEM..
The preemption mechanism we have for domain destruction is to return
-EAGAIN (and then user-space calls the hypercall again) and as such we need
to catch the case of:
domain_relinquish_resources
->vcpu_destroy_pagetables
-> put_page_and_type_preemptible
-> __put_page_type
returns -EINTR
and convert it to the proper type. For:
XEN_DOMCTL_setvcpucontext
-> vcpu_reset
-> vcpu_destroy_pagetables
we need to return -ERESTART otherwise we end up returning -ENOMEM.
There are also other callers of vcpu_destroy_pagetables: arch_vcpu_reset
(vcpu_reset) are:
- hvm_s3_suspend (asserts on any return code),
- vlapic_init_sipi_one (asserts on any return code),
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
master commit: de4f284b3d
master date: 2015-01-26 12:51:09 +0100
Only the low 32 bits are relevant.
For consistency also change a cast on regs->eax to regs->_eax.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: ae1edef1ae
master date: 2015-01-22 12:48:40 +0100
As done by the recent Linux commit b65d6e17fe ("kvm: x86: mask out
XSAVES") for KVM, we should also mask out XSAVES from what PV guests
get to see as long as we don't emulate accesses to MSR_IA32_XSS.
Actually, go beyond that: Just like for leaf 7, switch from
blacklisting to whitelisting, i.e. only allow XSAVEOPT and XSAVEC for
the time being. And do these overrides consistently for both Dom0 and
DomU-s.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 8d050ed109
master date: 2015-01-22 12:47:56 +0100
Xen event channels are not internal resources. They still have one end in a
domain, and are created at the request of privileged domains. This logic
which "successfully" creates a Xen event channel opens up undesirable failure
cases with ill-specified XSM policies.
If a domain is permitted to create ioreq servers or memevent listeners, but
not to create event channels, the ioreq/memevent creation will succeed but
attempting to bind the returned event channel will fail without any indication
of a permission error.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
master commit: 09aa4759fa
master date: 2015-01-20 10:42:26 +0100
XENMEM_{in,de}crease_reservation as well as XENMEM_populate_physmap
return the extent at which failure was detected, not error indicators.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Acked-by: Tim Deegan <tim@xen.org>
master commit: 76d4ff26d9
master date: 2015-01-19 11:59:05 +0100
While for us it's not as bad as it was for Linux, their commit
13e457e0ee ("KVM: x86: Emulator does not decode clflush well", by
Nadav Amit <namit@cs.technion.ac.il>) nevertheless points out two
shortcomings in our code: opcode 0F AE /7 is clflush only when it uses
a memory mode (otherwise it's SFENCE) and when there's no REP prefix
(an operand size prefix is fine, as that's CLFLUSHOPT).
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 9d03db6b81
master date: 2015-01-12 15:41:12 +0100
We need to make sure that last_vcpu is not pointing to VCPU whose
VPMU is being destroyed. Otherwise we may try to dereference it in
the future, when VCPU is gone.
We have to do this via IPI since otherwise there is a (somewheat
theoretical) chance that between test and subsequent clearing
of last_vcpu the remote processor (i.e. vpmu->last_pcpu) might do
both vpmu_load() and then vpmu_save() for another VCPU. The former
will clear last_vcpu and the latter will set it to something else.
Performing this operation via IPI will guarantee that nothing can
happen on the remote processor between testing and clearing of
last_vcpu.
We should also check for VPMU_CONTEXT_ALLOCATED in vpmu_destroy() to
avoid unnecessary percpu tests and arch-specific destroy ops. Thus
checks in AMD and Intel routines are no longer needed.
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Acked-by: Kevin Tian <kevin.tian@intel.com>
master commit: ed80171556
master date: 2015-01-07 11:12:27 +0100
This can (and will) be legitimately the case when sharing page tables
with EPT (more of a problem before p2m_access_rwx became zero, but
still possible even now when other than that is the default for a
guest), leading to an unconditional crash (in print_vtd_entries())
when a DMA remapping fault occurs.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
master commit: 46e0baf591
master date: 2015-01-07 11:13:58 +0100
Commit 545607eb3c ("x86: fix various issues with handling guest IRQs")
wasn't really consistent in one respect: The granting of access to an
IRQ shouldn't assume the pIRQ->IRQ translation to be the same in both
domains. In fact it is wrong to assume that a translation is already/
still in place at the time access is being granted/revoked.
What is wanted is to translate the incoming pIRQ to an IRQ for
the invoking domain (as the pIRQ is the only notion the invoking
domain has of the IRQ), and grant the subject domain access to
the resulting IRQ.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reported-by: Sander Eikelenboom <linux@eikelenboom.it>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
master commit: 6fb3a07bc0
master date: 2015-01-05 10:20:24 -0500
printk is not rated-limited by default. Therefore a malicious guest may
be able to flood the Xen console.
If we use gdprintk, unecessary information will be printed such as the
filename and the line. Instead use XENLOG_G_ERR combine with %pv.
This is XSA-118.
Signed-off-by: Julien Grall <julien.grall@linaro.org>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
[ relates to d0b2caa80f in master ]
',' is a valid character in a device-tree path (see ePAPR v1.1 Table
2-1), in fact ',' is actually pretty common in node names.
Using ',' as a separator breaks for example on fast models. If you use
the full path (/smb/motherboard/iofpga@3,00000000/uart@090000) rather
than the alias then earlyprintk gives:
(XEN) Looking for UART console /smb/motherboard/iofpga@3
(XEN) Unable to find device "/smb/motherboard/iofpga@3"
(XEN) Bad console= option 'dtuart'
I actually noticed this on Jetson where the uart is
"/serial@0,70006300" and there happened to be no alias defined.
Instead use ':' as the separator, it is defined to terminate the path
in the context of /chosen/stdout-path (Table 3-4) which is pretty
closely analogous to the dtuart= option and so makes a pretty good
choice (especially since the next patch adds support for stdout-path).
Since no DT aware driver current supports any options there is no
point in retaining support for ',' for backwards compatibility.
Additionally, expand the buffer for the dtuart option, a path can be
far longer than 30 characters (in fact the maximum size of a single
node name is 31, so it's not even necessarily enough for an alias).
128 is completely arbitrary and allows for paths at least 8 deep even
with worst case node names.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Reviewed-by: Julien Grall <julien.grall@linaro.org>
(cherry picked from commit f01af57300)
Conflicts:
docs/misc/xen-command-line.markdown
-- dropped since precursor patch not present.