]> xenbits.xensource.com Git - xen.git/log
xen.git
8 years agoupdate Xen version to 4.8.2-pre
Jan Beulich [Tue, 2 May 2017 12:55:09 +0000 (14:55 +0200)]
update Xen version to 4.8.2-pre

8 years agox86: discard type information when stealing pages
Jan Beulich [Tue, 2 May 2017 12:54:26 +0000 (14:54 +0200)]
x86: discard type information when stealing pages

While a page having just a single general reference left necessarily
has a zero type reference count too, its type may still be valid (and
in validated state; at present this is only possible and relevant for
PGT_seg_desc_page, as page tables have their type forcibly zapped when
their type reference count drops to zero, and
PGT_{writable,shared}_page pages don't require any validation). In
such a case when the page is being re-used with the same type again,
validation is being skipped. As validation criteria differ between
32- and 64-bit guests, pages to be transferred between guests need to
have their validation indicator zapped (and with it we zap all other
type information at once).

This is XSA-214.

Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: eaf537342c909875c10f49b06e17493655410681
master date: 2017-05-02 14:46:58 +0200

8 years agomulticall: deal with early exit conditions
Jan Beulich [Tue, 2 May 2017 12:52:54 +0000 (14:52 +0200)]
multicall: deal with early exit conditions

In particular changes to guest privilege level require the multicall
sequence to be aborted, as hypercalls are permitted from kernel mode
only. While likely not very useful in a multicall, also properly handle
the return value in the HYPERVISOR_iret case (which should be the guest
specified value).

This is XSA-213.

Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Julien Grall <julien.grall@arm.com>
master commit: 22c096c99d8c05833c3c19870e36efb2dd4e8013
master date: 2017-05-02 14:45:02 +0200

8 years agoMerge branch 'staging-4.8' of xenbits.xen.org:/home/xen/git/xen into staging-4.8
Jan Beulich [Mon, 10 Apr 2017 13:24:47 +0000 (15:24 +0200)]
Merge branch 'staging-4.8' of xenbits.xen.org:/home/xen/git/xen into staging-4.8

8 years agoupdate Xen version to 4.8.1 RELEASE-4.8.1
Jan Beulich [Mon, 10 Apr 2017 13:21:48 +0000 (15:21 +0200)]
update Xen version to 4.8.1

8 years agosetup vwfi correctly on cpu0
Stefano Stabellini [Fri, 31 Mar 2017 22:37:07 +0000 (15:37 -0700)]
setup vwfi correctly on cpu0

parse_vwfi runs after init_traps on cpu0, potentially resulting in the
wrong HCR_EL2 for it. Secondary cpus boot after parse_vwfi, so in their
case init_traps will write the correct set of flags to HCR_EL2.

For cpu0, fix the issue by changing HCR_EL2 setting from a new
presmp_initcall.

Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Julien Grall <julien.grall@arm.com>
8 years agooxenstored: trim history in the frequent_ops function
Thomas Sanders [Tue, 28 Mar 2017 17:57:52 +0000 (18:57 +0100)]
oxenstored: trim history in the frequent_ops function

We were trimming the history of commits only at the end of each
transaction (regardless of how it ended).

Therefore if non-transactional writes were being made but no
transactions were being ended, the history would grow
indefinitely. Now we trim the history at regular intervals.

Signed-off-by: Thomas Sanders <thomas.sanders@citrix.com>
8 years agooxenstored transaction conflicts: improve logging
Thomas Sanders [Mon, 27 Mar 2017 13:36:34 +0000 (14:36 +0100)]
oxenstored transaction conflicts: improve logging

For information related to transaction conflicts, potentially frequent
logging at "info" priority has been changed to "debug" priority, and
once per two minutes there is an "info" priority summary.

Additional detailed logging has been added at "debug" priority.

Reported-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Thomas Sanders <thomas.sanders@citrix.com>
8 years agooxenstored: don't wake to issue no conflict-credit
Thomas Sanders [Fri, 24 Mar 2017 19:55:03 +0000 (19:55 +0000)]
oxenstored: don't wake to issue no conflict-credit

In the main loop, when choosing the timeout for the select function
call, we were setting it so as to wake up to issue conflict-credit to
any domains that could accept it. When xenstore is idle, this would
mean waking up every 50ms (by default) to do no work. With this
commit, we check whether any domain is below its cap, and if not then
we set the timeout for longer (the same timeout as before the
conflict-protection feature was added).

Reported-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Thomas Sanders <thomas.sanders@citrix.com>
Reviewed-by: Jonathan Davies <jonathan.davies@citrix.com>
8 years agooxenstored: do not commit read-only transactions
Thomas Sanders [Fri, 24 Mar 2017 16:16:10 +0000 (16:16 +0000)]
oxenstored: do not commit read-only transactions

The packet telling us to end the transaction has always carried an
argument telling us whether to commit.

If the transaction made no modifications to the tree, now we ignore
that argument and do not commit: it is just a waste of effort.

This makes read-only transactions immune to conflicts, and means that
we do not need to store any of their details in the history that is
used for assigning blame for conflicts.

We count a transaction as a read-only transaction only if it contains
no operations that modified the tree.

This means that (for example) a transaction that creates a new node
then deletes it would NOT count as read-only, even though it makes no
change overall. A more sophisticated algorithm could judge the
transaction based on comparison of its initial and final states, but
this would add complexity and computational cost.

Reported-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Thomas Sanders <thomas.sanders@citrix.com>
Reviewed-by: Jonathan Davies <jonathan.davies@citrix.com>
8 years agooxenstored: allow self-conflicts
Thomas Sanders [Thu, 23 Mar 2017 19:06:54 +0000 (19:06 +0000)]
oxenstored: allow self-conflicts

We already avoid inter-domain conflicts but now allow intra-domain
conflicts.  Although there are no known practical examples of a domain
that might perform operations that conflict with its own transactions,
this is conceivable, so here we avoid changing those semantics
unnecessarily.

When a transaction commit fails with a conflict and we look through
the history of commits to see which connection(s) to blame, ignore
historical commits that were made by the same connection as the
failing commit.

Reported-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Thomas Sanders <thomas.sanders@citrix.com>
Reviewed-by: Jonathan Davies <jonathan.davies@citrix.com>
8 years agooxenstored: blame the connection that caused a transaction conflict
Jonathan Davies [Thu, 23 Mar 2017 14:28:16 +0000 (14:28 +0000)]
oxenstored: blame the connection that caused a transaction conflict

Blame each connection found to have made a commit that would cause this
transaction to fail. Each blamed connection is penalised by having its
conflict-credit decremented.

Note the change in semantics for the replay function: we no longer stop after
finding the first operation that can't be replayed. This allows us to identify
all operations that conflicted with this transaction, not just the one that
conflicted first.

Signed-off-by: Jonathan Davies <jonathan.davies@citrix.com>
Signed-off-by: Thomas Sanders <thomas.sanders@citrix.com>
v1 Reviewed-by: Christian Lindig <christian.lindig@citrix.com>

Changes since v1:
 * use correct log levels for informational messages
Changes since v2:
 * fix the blame algorithm and improve logging
   (fix was reviewed by Jonathan Davies)

Reported-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Thomas Sanders <thomas.sanders@citrix.com>
8 years agooxenstored: track commit history
Jonathan Davies [Mon, 27 Mar 2017 08:58:29 +0000 (08:58 +0000)]
oxenstored: track commit history

Since the list of historic activity cannot grow without bound, it is safe to use
this to track commits.

Reported-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Jonathan Davies <jonathan.davies@citrix.com>
Reviewed-by: Thomas Sanders <thomas.sanders@citrix.com>
8 years agooxenstored: discard old commit-history on txn end
Thomas Sanders [Thu, 23 Mar 2017 14:25:16 +0000 (14:25 +0000)]
oxenstored: discard old commit-history on txn end

The history of commits is to be used for working out which historical
commit(s) (including atomic writes) caused conflicts with a
currently-failing commit of a transaction. Any commit that was made
before the current transaction started cannot be relevant. Therefore
we never need to keep history from before the start of the
longest-running transaction that is open at any given time: whenever a
transaction ends (with or without a commit) then if it was the
longest-running open transaction we can delete history up until start
of the the next-longest-running open transaction.

Some transactions might stay open for a very long time, so if any
transaction exceeds conflict_max_history_seconds then we remove it
from consideration in this context, and will not guarantee to keep
remembering about historical commits made during such a transaction.

We implement this by keeping a list of all open transactions that have
not been open too long. When a transaction ends, we remove it from the
list, along with any that have been open longer than the maximum; then
we delete any history from before the start of the longest-running
transaction remaining in the list.

Reported-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Thomas Sanders <thomas.sanders@citrix.com>
Reviewed-by: Jonathan Davies <jonathan.davies@citrix.com>
Reviewed-by: Christian Lindig <christian.lindig@citrix.com>
8 years agooxenstored: only record operations with side-effects in history
Jonathan Davies [Thu, 23 Mar 2017 14:20:33 +0000 (14:20 +0000)]
oxenstored: only record operations with side-effects in history

There is no need to record "read" operations as they will never cause another
transaction to fail.

Reported-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Jonathan Davies <jonathan.davies@citrix.com>
Reviewed-by: Thomas Sanders <thomas.sanders@citrix.com>
8 years agooxenstored: support commit history tracking
Jonathan Davies [Tue, 14 Mar 2017 13:20:07 +0000 (13:20 +0000)]
oxenstored: support commit history tracking

Add ability to track xenstore tree operations -- either non-transactional
operations or committed transactions.

For now, the call to actually retain commits is commented out because history
can grow without bound.

For now, we call record_commit for all non-transactional operations. A
subsequent patch will make it retain only the ones with side-effects.

Reported-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Jonathan Davies <jonathan.davies@citrix.com>
Signed-off-by: Thomas Sanders <thomas.sanders@citrix.com>
Reviewed-by: Christian Lindig <christian.lindig@citrix.com>
8 years agooxenstored: add transaction info relevant to history-tracking
Jonathan Davies [Tue, 14 Mar 2017 12:17:38 +0000 (12:17 +0000)]
oxenstored: add transaction info relevant to history-tracking

Specifically:
 * retain the original store (not just the root) in full transactions
 * store commit count at the time of the start of the transaction

Reported-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Jonathan Davies <jonathan.davies@citrix.com>
Reviewed-by: Thomas Sanders <thomas.sanders@citrix.com>
Reviewed-by: Ian Jackson <ian.jackson@eu.citrix.com>
Reviewed-by: Christian Lindig <christian.lindig@citrix.com>
8 years agooxenstored: ignore domains with no conflict-credit
Thomas Sanders [Tue, 14 Mar 2017 12:15:52 +0000 (12:15 +0000)]
oxenstored: ignore domains with no conflict-credit

When processing connections, skip those from domains with no remaining
conflict-credit.

Also, issue a point of conflict-credit at regular intervals, the
period being set by the configuration option "conflict-max-history-
seconds".  When issuing conflict-credit, we give a point either to
every domain at once (one each) or only to the single domain at the
front of the queue, depending on the configuration option
"conflict-rate-limit-is-aggregate".

Reported-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Thomas Sanders <thomas.sanders@citrix.com>
Reviewed-by: Jonathan Davies <jonathan.davies@citrix.com>
Reviewed-by: Christian Lindig <christian.lindig@citrix.com>
8 years agooxenstored: handling of domain conflict-credit
Thomas Sanders [Tue, 14 Mar 2017 12:15:52 +0000 (12:15 +0000)]
oxenstored: handling of domain conflict-credit

This commit gives each domain a conflict-credit variable, which will
later be used for limiting how often a domain can cause other domain's
transaction-commits to fail.

This commit also provides functions and data for manipulating domains
and their conflict-credit, and checking whether they have credit.

Reported-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Thomas Sanders <thomas.sanders@citrix.com>
Reviewed-by: Jonathan Davies <jonathan.davies@citrix.com>
Reviewed-by: Christian Lindig <christian.lindig@citrix.com>
8 years agooxenstored: comments explaining some variables
Thomas Sanders [Tue, 14 Mar 2017 12:15:52 +0000 (12:15 +0000)]
oxenstored: comments explaining some variables

It took a while of reading and reasoning to work out what these are
for, so here are comments to make life easier for everyone reading
this code in future.

Reported-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Thomas Sanders <thomas.sanders@citrix.com>
Reviewed-by: Jonathan Davies <jonathan.davies@citrix.com>
Reviewed-by: Ian Jackson <ian.jackson@eu.citrix.com>
Reviewed-by: Christian Lindig <christian.lindig@citrix.com>
8 years agoxenstored: Log when the write transaction rate limit bites
Ian Jackson [Tue, 7 Mar 2017 16:09:13 +0000 (16:09 +0000)]
xenstored: Log when the write transaction rate limit bites

Reported-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
plus:

xenstore: dont increment bool variable
Instead of incrementing a bool variable just set it to true.

Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
8 years agoxenstored: apply a write transaction rate limit
Ian Jackson [Tue, 7 Mar 2017 16:09:12 +0000 (16:09 +0000)]
xenstored: apply a write transaction rate limit

This avoids a rogue client being about to stall another client (eg the
toolstack) indefinitely.

This is XSA-206.

Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Backported to 4.8 (not entirely trivial).

Reported-by: Juergen Gross <jgross@suse.com>
Signed-off-by: George Dunlap <george.dunlap@citrix.com>
Acked-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
8 years agotools/libxenctrl: fix error check after opening libxenforeignmemory
Paul Durrant [Wed, 22 Feb 2017 13:27:34 +0000 (13:27 +0000)]
tools/libxenctrl: fix error check after opening libxenforeignmemory

Checking the value of xch->xcall is clearly incorrect. The code should be
checking xch->fmem (i.e. the return of the previously called function).

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
(cherry picked from commit 80a7d04f532ddc3500acd7988917708a536ae15f)

8 years agolibxl: correct xenstore entry for empty cdrom
Juergen Gross [Wed, 15 Feb 2017 11:11:12 +0000 (12:11 +0100)]
libxl: correct xenstore entry for empty cdrom

Specifying an empty cdrom device will result in a Xenstore entry

params = aio:(null)

as the physical device path isn't existing. This lets a domain booted
via OVMF hang as OVMF is checking for "aio:" only in order to detect
the empty cdrom case.

Use an empty string for the physical device path in this case. As a
cdrom device for HVM is always backed by qdisk we only need to cover this
backend.

Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
8 years agox86: use 64 bit mask when masking away mfn bits
Juergen Gross [Tue, 4 Apr 2017 12:55:55 +0000 (14:55 +0200)]
x86: use 64 bit mask when masking away mfn bits

When using _PAGE_PSE_PAT as base for a negated bit mask make sure it is
propagated to 64 bits when applied to a 64 bit value.

There seems to be only one place where this is a problem, so fix this
by casting _PAGE_PSE_PAT to 64 bits there.

Not doing so will probably lead to problems on hosts with more than
16 TB of memory.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: George Dunlap <george.dunlap@citrix.com>
master commit: 4edb1a42e3320757e3559f17edf6903bc1777de3
master date: 2017-03-30 15:11:24 +0200

8 years agomemory: properly check guest memory ranges in XENMEM_exchange handling
Jan Beulich [Tue, 4 Apr 2017 12:55:00 +0000 (14:55 +0200)]
memory: properly check guest memory ranges in XENMEM_exchange handling

The use of guest_handle_okay() here (as introduced by the XSA-29 fix)
is insufficient here, guest_handle_subrange_okay() needs to be used
instead.

Note that the uses are okay in
- XENMEM_add_to_physmap_batch handling due to the size field being only
  16 bits wide,
- livepatch_list() due to the limit of 1024 enforced on the
  number-of-entries input (leaving aside the fact that this can be
  called by a privileged domain only anyway),
- compat mode handling due to counts there being limited to 32 bits,
- everywhere else due to guest arrays being accessed sequentially from
  index zero.

This is CVE-2017-7228 / XSA-212.

Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 938fd2586eb081bcbd694f4c1f09ae6a263b0d90
master date: 2017-04-04 14:47:46 +0200

8 years agoxen: sched: don't call hooks of the wrong scheduler via VCPU2OP
Dario Faggioli [Fri, 31 Mar 2017 06:33:20 +0000 (08:33 +0200)]
xen: sched: don't call hooks of the wrong scheduler via VCPU2OP

Within context_saved(), we call the context_saved hook,
and we use VCPU2OP() to determine from what scheduler.
VCPU2OP uses DOM2OP, which uses d->cpupool, which is
NULL when d is the idle domain. And in that case,
DOM2OP just returns ops, the scheduler of cpupool0.

Therefore, if:
- cpupool0's scheduler defines context_saved (like
  Credit2 and RTDS do),
- we are not in cpupool0 (i.e., our scheduler is
  not ops),
- we are context switching from idle,

we call VCPU2OP(idle_vcpu), which means
DOM2OP(idle->cpupool), which is ops.

Therefore, we both:
- check if context_saved is defined in the wrong
  scheduler;
- if yes, call the wrong one.

When using Credit2 at boot, and also Credit2 in
the other cpupool, this is wrong but innocuous,
because it only involves the idle vcpus.

When using Credit2 at boot, and Credit1 in the
other cpupool, this is *totally* wrong, and
it's by chance it does not explode!

When using Credit2 and other schedulers I'm
developping, I hit the following assert (in
sched_credit2.c, on a CPU inside a cpupool that
does not use Credit2):

csched2_context_saved()
{
 ...
 ASSERT(!vcpu_on_runq(svc));
 ...
}

Fix this by dealing explicitly, in VCPU2OP, with
idle vcpus, returning the scheduler of the pCPU
they (always) run on.

Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Reviewed-by: George Dunlap <george.dunlap@citrix.com>
master commit: a3653e6a279213ba4e883b2252415dc98633106a
master date: 2017-03-27 14:28:05 +0100

8 years agox86/EFI: avoid Xen image when looking for module/kexec position
Jan Beulich [Fri, 31 Mar 2017 06:32:51 +0000 (08:32 +0200)]
x86/EFI: avoid Xen image when looking for module/kexec position

When booting straight from EFI, we don't further try to relocate Xen.
As a result, so far we also didn't avoid the area Xen uses when looking
for a location to put modules or the kexec area. Introduce a fake
module slot to deal with that without having to fiddle with a lot of
code.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: e22e1c47958a4778cd7baa3980f74e52f525ba28
master date: 2017-03-20 09:27:12 +0100

8 years agox86/EFI: avoid IOMMU faults on [_end,__2M_rwdata_end)
Jan Beulich [Fri, 31 Mar 2017 06:32:22 +0000 (08:32 +0200)]
x86/EFI: avoid IOMMU faults on [_end,__2M_rwdata_end)

Commit c9a4a1c419 ("x86/layout: Correct Xen's idea of its own memory
layout") didn't go far enough with the conversion, causing IOMMU faults
when memory from that range was handed to a domain. We must not make
this memory available for allocation (the change is benign to xen.gz at
this point in time).

Note that the change to tboot_shutdown() is fixing another issue at
once: As it looks, the function so far skipped all memory below the Xen
image.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: d522571a408a7dd21a06705f6dd51cdafd2db4fc
master date: 2017-03-20 09:25:36 +0100

8 years agox86/EFI: avoid overrunning mb_modules[]
Jan Beulich [Fri, 31 Mar 2017 06:31:53 +0000 (08:31 +0200)]
x86/EFI: avoid overrunning mb_modules[]

Commit 436fb462ab ("x86/microcode: enable boot time (pre-Dom0)
loading") added a 4th module without providing an array slot for it.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 02b37b7eff39e40828041b2fe480725ab8443258
master date: 2017-03-17 15:45:22 +0100

8 years agobuild/clang: fix XSM dummy policy when using clang 4.0
Roger Pau Monné [Fri, 31 Mar 2017 06:31:14 +0000 (08:31 +0200)]
build/clang: fix XSM dummy policy when using clang 4.0

There seems to be some weird bug in clang 4.0 that prevents xsm_pmu_op from
working as expected, and vpmu.o ends up with a reference to
__xsm_action_mismatch_detected which makes the build fail:

[...]
ld    -melf_x86_64_fbsd  -T xen.lds -N prelink.o  \
    xen/common/symbols-dummy.o -o xen/.xen-syms.0
prelink.o: In function `xsm_default_action':
xen/include/xsm/dummy.h:80: undefined reference to `__xsm_action_mismatch_detected'
xen/xen/include/xsm/dummy.h:80: relocation truncated to fit: R_X86_64_PC32 against undefined symbol `__xsm_action_mismatch_detected'
ld: xen/xen/.xen-syms.0: hidden symbol `__xsm_action_mismatch_detected' isn't defined

Then doing a search in the objects files:

# find xen/ -type f -name '*.o' -print0 | xargs -0 bash -c \
  'for filename; do nm "$filename" | \
  grep -q __xsm_action_mismatch_detected && echo "$filename"; done' bash
xen/arch/x86/prelink.o
xen/arch/x86/cpu/vpmu.o
xen/arch/x86/cpu/built_in.o
xen/arch/x86/built_in.o

The current patch is the only way I've found to fix this so far, by simply
moving the XSM_PRIV check into the default case in xsm_pmu_op. This also fixes
the behavior of do_xenpmu_op, which will now return -EINVAL for unknown
XENPMU_* operations, instead of -EPERM when called by a privileged domain.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
master commit: 9e4d116faff4545a7f21c2b01008e94d68e6db58
master date: 2017-03-14 18:19:29 +0100

8 years agox86: drop unneeded __packed attributes
Roger Pau Monné [Fri, 31 Mar 2017 06:28:49 +0000 (08:28 +0200)]
x86: drop unneeded __packed attributes

There where a couple of unneeded packed attributes in several x86-specific
structures, that are obviously aligned. The only non-trivial one is
vmcb_struct, which has been checked to have the same layout with and without
the packed attribute using pahole. In that case add a build-time size check to
be on the safe side.

No functional change is expected as a result of this commit.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
master commit: 4036e7c592905c2292cdeba8269e969959427237
master date: 2017-03-07 17:11:06 +0100

8 years agoarm: xen_size should be paddr_t for consistency
Stefano Stabellini [Wed, 29 Mar 2017 18:32:34 +0000 (11:32 -0700)]
arm: xen_size should be paddr_t for consistency

Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Julien Grall <julien.grall@arm.com>
8 years agoxen/arm: alternative: Register re-mapped Xen area as a temporary virtual region
Wei Chen [Mon, 27 Mar 2017 08:40:50 +0000 (16:40 +0800)]
xen/arm: alternative: Register re-mapped Xen area as a temporary virtual region

While I was using the alternative patching in the SErrors patch series [1].
I used a branch instruction as alternative instruction.

        ALTERNATIVE("nop",
                    "b skip_check",
                    SKIP_CHECK_PENDING_VSERROR)

Unfortunately, I got a system panic message with this code:

(XEN) build-id: f64081d86e7e88504b7d00e1486f25751c004e39
(XEN) alternatives: Patching with alt table 100b9480 -> 100b9498
(XEN) Xen BUG at alternative.c:61
(XEN) ----[ Xen-4.9-unstable  arm32  debug=y   Tainted:  C   ]----
(XEN) CPU:    0
(XEN) PC:     00252b68 alternative.c#__apply_alternatives+0x128/0x1d4
(XEN) CPSR:   800000da MODE:Hypervisor
(XEN)      R0: 00000000 R1: 00000000 R2: 100b9490 R3: 100b949c
(XEN)      R4: eafeff84 R5: 00000000 R6: 100b949c R7: 10079290
(XEN)      R8: 100792ac R9: 00000001 R10:100b948c R11:002cfe04 R12:002932c0
(XEN) HYP: SP: 002cfdc4 LR: 00239128
(XEN)
(XEN)   VTCR_EL2: 80003558
(XEN)  VTTBR_EL2: 0000000000000000
(XEN)
(XEN)  SCTLR_EL2: 30cd187f
(XEN)    HCR_EL2: 000000000038663f
(XEN)  TTBR0_EL2: 00000000bff09000
(XEN)
(XEN)    ESR_EL2: 00000000
(XEN)  HPFAR_EL2: 0000000000000000
(XEN)      HDFAR: 00000000
(XEN)      HIFAR: 00000000
(XEN)
(XEN) Xen stack trace from sp=002cfdc4:
(XEN)    00000000 00294328 002e0004 00000001 10079290 002cfe14 100b9490 00000000
(XEN)    10010000 10122700 00200000 002cfe1c 00000080 00252c14 00000000 002cfe64
(XEN)    00252dd8 00000007 00000000 000bfe00 100b9480 100b9498 002cfe1c 002cfe1c
(XEN)    10010000 10122700 00000000 00000000 00000000 00000000 00000000 00000000
(XEN)    00000000 00000000 00000000 002ddf30 00000000 003113e8 0030f018 002cfe9c
(XEN)    00238914 00000002 00000000 00000000 00000000 0028b000 00000002 00293800
(XEN)    00000002 0030f238 00000002 00290640 00000001 002cfea4 002a2840 002cff54
(XEN)    002a65fc 11112131 10011142 00000000 0028d194 00000000 00000000 00000000
(XEN)    bdffb000 80000000 00000000 c0000000 00000000 00000002 00000000 c0000000
(XEN)    002b8060 00002000 002b8040 00000000 c0000000 bc000000 00000000 c0000000
(XEN)    00000000 be000000 00000000 00112701 00000000 bff12701 00000000 00000000
(XEN)    00000000 00000000 00000000 00000000 00000018 00000000 00000001 00000000
(XEN)    9fece000 80200000 80000000 00400000 00200550 00000000 00000000 00000000
(XEN)    00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
(XEN)    00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
(XEN)    00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
(XEN)    00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
(XEN)    00000000 00000000 00000000 00000000 00000000 00000000 00000000
(XEN) Xen call trace:
(XEN)    [<00252b68>] alternative.c#__apply_alternatives+0x128/0x1d4 (PC)
(XEN)    [<00239128>] is_active_kernel_text+0x10/0x28 (LR)
(XEN)    [<00252dd8>] alternative.c#__apply_alternatives_multi_stop+0x1c4/0x204
(XEN)    [<00238914>] stop_machine_run+0x1e8/0x254
(XEN)    [<002a2840>] apply_alternatives_all+0x38/0x54
(XEN)    [<002a65fc>] start_xen+0xcf4/0xf88
(XEN)    [<00200550>] arm32/head.o#paging+0x94/0xd8
(XEN)
(XEN)
(XEN) ****************************************
(XEN) Panic on CPU 0:
(XEN) Xen BUG at alternative.c:61
(XEN) ****************************************

This panic was triggered by the BUG(); in branch_insn_requires_update.
That's because in this case the alternative patching needs to update the
offset of the branch instruction. But the new target address of the branch
instruction could not pass the check of is_active_kernel_text();

The reason is that: When Xen is booting, it will call apply_alternatives_all
to do patching with alternative tables. In this progress, we should update
the offset of branch instructions if required. This means we should modify
the Xen text section. But Xen text section is marked as read-only and we
configure the hardware to not allow a region to be writable and executable at
the same time. So we re-map Xen in a temporary area for writing. In this case,
the calculation of the new target address of the branch instruction is based
on this re-mapped area. The new target address will point to a value in the
re-mapped area. But we haven't registered this area as an active kernel text.
So the check of is_active_kernel_text will always return false.

We have to register the re-mapped Xen area as a virtual region temporarily to
solve this problem.

1. https://lists.xenproject.org/archives/html/xen-devel/2017-03/msg01939.html

Signed-off-by: Wei Chen <Wei.Chen@arm.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Julien Grall <julien.grall@arm.com>
8 years agoQEMU_TAG update
Ian Jackson [Tue, 21 Mar 2017 18:44:24 +0000 (18:44 +0000)]
QEMU_TAG update

8 years agoarm: read/write rank->vcpu atomically
Stefano Stabellini [Sat, 11 Feb 2017 02:05:22 +0000 (18:05 -0800)]
arm: read/write rank->vcpu atomically

We don't need a lock in vgic_get_target_vcpu anymore, solving the
following lock inversion bug: the rank lock should be taken first, then
the vgic lock. However, gic_update_one_lr is called with the vgic lock
held, and it calls vgic_get_target_vcpu, which tries to obtain the rank
lock.

Coverity-ID: 1381855
Coverity-ID: 1381853

Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Julien Grall <julien.grall@arm.com>
8 years agoxen/arm: p2m: Perform local TLB invalidation on vCPU migration
Julien Grall [Wed, 8 Mar 2017 18:06:02 +0000 (18:06 +0000)]
xen/arm: p2m: Perform local TLB invalidation on vCPU migration

The ARM architecture allows an OS to have per-CPU page tables, as it
guarantees that TLBs never migrate from one CPU to another.

This works fine until this is done in a guest. Consider the following
scenario:
    - vcpu-0 maps P to V
    - vpcu-1 maps P' to V

If run on the same physical CPU, vcpu-1 can hit in TLBs generated by
vcpu-0 accesses, and access the wrong physical page.

The solution to this is to keep a per-p2m map of which vCPU ran the last
on each given pCPU and invalidate local TLBs if two vPCUs from the same
VM run on the same CPU.

Unfortunately it is not possible to allocate per-cpu variable on the
fly. So for now the size of the array is NR_CPUS, this is fine because
we still have space in the structure domain. We may want to add an
helper to allocate per-cpu variable in the future.

Signed-off-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
8 years agoxen/arm: Introduce INVALID_VCPU_ID
Julien Grall [Wed, 8 Mar 2017 18:06:01 +0000 (18:06 +0000)]
xen/arm: Introduce INVALID_VCPU_ID

Define INVALID_VCPU_ID as MAX_VIRT_CPUS to avoid casting problem later
on. At the moment it can always fit in uint8_t.

Signed-off-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
8 years agoxen/arm: Set nr_cpu_ids to available number of cpus
Vijaya Kumar K [Mon, 1 Feb 2016 09:26:13 +0000 (14:56 +0530)]
xen/arm: Set nr_cpu_ids to available number of cpus

nr_cpu_ids for arm platforms is incorrectly set to NR_CPUS
irrespective of the number of cpus supported by platform.

Signed-off-by: Vijaya Kumar K <Vijaya.Kumar@caviumnetworks.com>
Reviewed-by: Julien Grall <julien.grall@citrix.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
8 years agoxen/arm: acpi: Relax hw domain mapping attributes to p2m_mmio_direct_c
Edgar E. Iglesias [Thu, 26 Jan 2017 13:16:02 +0000 (14:16 +0100)]
xen/arm: acpi: Relax hw domain mapping attributes to p2m_mmio_direct_c

Since the hardware domain is a trusted domain, we extend the
trust to include making final decisions on what attributes to
use when mapping memory regions.

For ACPI configured hardware domains, this patch relaxes the hardware
domains mapping attributes to p2m_mmio_direct_c. This will allow the
hardware domain to control the attributes via its S1 mappings.

Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Acked-by: Julien Grall <julien.grall@arm.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
8 years agoRevert "xen/arm: Map mmio-sram nodes as un-cached memory"
Edgar E. Iglesias [Thu, 26 Jan 2017 13:16:01 +0000 (14:16 +0100)]
Revert "xen/arm: Map mmio-sram nodes as un-cached memory"

This reverts commit 1e75ed8b64bc1a9b47e540e6f100f17ec6d97f1b.

The default attribute mapping for MMIO as been relaxed and now rely on
the hardware domain to set the correct memory attribute

Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
8 years agoxen/arm: dt: Relax hw domain mapping attributes to p2m_mmio_direct_c
Edgar E. Iglesias [Thu, 26 Jan 2017 13:16:00 +0000 (14:16 +0100)]
xen/arm: dt: Relax hw domain mapping attributes to p2m_mmio_direct_c

Since the hardware domain is a trusted domain, we extend the
trust to include making final decisions on what attributes to
use when mapping memory regions.

For device-tree configured hardware domains, this patch relaxes
the hardware domains mapping attributes to p2m_mmio_direct_c.
This will allow the hardware domain to control the attributes
via its S1 mappings.

Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Reviewed-by: Julien Grall <julien.grall@arm.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
8 years agoxen/arm: flush icache as well when XEN_DOMCTL_cacheflush is issued
Tamas K Lengyel [Fri, 27 Jan 2017 18:25:23 +0000 (11:25 -0700)]
xen/arm: flush icache as well when XEN_DOMCTL_cacheflush is issued

When the toolstack modifies memory of a running ARM VM it may happen
that the underlying memory of a current vCPU PC is changed. Without
flushing the icache the vCPU may continue executing stale instructions.

Also expose the xc_domain_cacheflush through xenctrl.h.

Signed-off-by: Tamas K Lengyel <tamas.lengyel@zentific.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
8 years agoxen/arm: fix GIC_INVALID_LR
Stefano Stabellini [Thu, 22 Dec 2016 02:15:10 +0000 (18:15 -0800)]
xen/arm: fix GIC_INVALID_LR

GIC_INVALID_LR should be 0xff, but actually, defined as ~(uint8_t)0, is
0xffffffff. Fix the problem by placing the ~ operator before the cast.

Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Julien Grall <julien.grall@arm.com>
8 years agofix out of bound access to mode_strings
Stefano Stabellini [Fri, 9 Dec 2016 01:17:04 +0000 (17:17 -0800)]
fix out of bound access to mode_strings

mode == ARRAY_SIZE(mode_strings) causes an out of bound access to
the mode_strings array.

Coverity-ID: 1381859

Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Julien Grall <julien.grall@arm.com>
8 years agomissing vgic_unlock_rank in gic_remove_irq_from_guest
Stefano Stabellini [Fri, 9 Dec 2016 00:59:28 +0000 (16:59 -0800)]
missing vgic_unlock_rank in gic_remove_irq_from_guest

Add missing vgic_unlock_rank on the error path in
gic_remove_irq_from_guest.

Coverity-ID: 1381843

Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Julien Grall <julien.grall@arm.com>
8 years agoxen/arm: Fix macro for ARM Jazelle CPU feature identification
Artem Mygaiev [Tue, 6 Dec 2016 14:16:45 +0000 (16:16 +0200)]
xen/arm: Fix macro for ARM Jazelle CPU feature identification

Fix macro for ARM Jazelle CPU feature identification: value of 0 indicates
that CPU does not support ARM Jazelle (ID_PFR0[11:8])

Coverity-ID: 1381849

Signed-off-by: Artem Mygaiev <artem_mygaiev@epam.com>
Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Julien Grall <julien.grall@arm.com>
8 years agoxen/arm: traps: Emulate ICC_SRE_EL1 as RAZ/WI
Julien Grall [Mon, 5 Dec 2016 17:43:23 +0000 (17:43 +0000)]
xen/arm: traps: Emulate ICC_SRE_EL1 as RAZ/WI

Recent Linux kernel (4.4 and onwards [1]) is checking whether it is possible
to enable sysreg access (ICC_SRE_EL1.SRE) when the ID register
(ID_AA64PRF0_EL1.GIC) is reporting the presence of the sysreg interface.

When the guest has been configured to use GICv2, the hypervisor will
disable sysreg access for this vm (via ICC_SRE_EL2.Enable) and therefore
access to system register such as ICC_SRE_EL1 are trapped in EL2.

However, ICC_SRE_EL1 is not emulated by the hypervisor. This means that
Linux will crash as soon as it is trying to access ICC_SRE_EL1.

To solve this problem, Xen can implement ICC_SRE_EL1 as read-as-zero
write-ignore. The emulation will only be used when sysreg are disabled
for EL1.

[1]  963fcd409 "arm64: cpufeatures: Check ICC_EL1_SRE.SRE before
enabling ARM64_HAS_SYSREG_GIC_CPUIF"

Signed-off-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
8 years agoxen/arm: Fix misplaced parentheses for PSCI version check
Artem Mygaiev [Wed, 30 Nov 2016 13:53:11 +0000 (15:53 +0200)]
xen/arm: Fix misplaced parentheses for PSCI version check

Fix misplaced parentheses for PSCI version check

Signed-off-by: Artem Mygaiev <artem_mygaiev@epam.com>
Reviewed-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
8 years agoarm/irq: Reorder check when the IRQ is already used by someone
Oleksandr Tyshchenko [Fri, 2 Dec 2016 16:38:16 +0000 (18:38 +0200)]
arm/irq: Reorder check when the IRQ is already used by someone

Call irq_get_domain for the IRQ we are interested in
only after making sure that it is the guest IRQ to avoid
ASSERT(test_bit(_IRQ_GUEST, &desc->status)) triggering.

Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Signed-off-by: Andrii Anisov <andrii_anisov@epam.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
8 years agoDon't clear HCR_VM bit when updating VTTBR.
Jun Sun [Mon, 10 Oct 2016 19:27:56 +0000 (12:27 -0700)]
Don't clear HCR_VM bit when updating VTTBR.

Currently function p2m_restore_state() would clear HCR_VM bit, i.e.,
disabling stage2 translation, before updating VTTBR register. After
some research and talking to ARM support, I got confirmed that this is not
necessary. We are currently working on a new platform that would need this
to be removed.

The patch is tested on FVP foundation model.

Signed-off-by: Jun Sun <jsun@junsun.net>
Acked-by: Steve Capper <steve.capper@linaro.org>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
8 years agox86/emul: Correct the decoding of mov to/from cr/dr
Andrew Cooper [Tue, 14 Mar 2017 11:43:25 +0000 (12:43 +0100)]
x86/emul: Correct the decoding of mov to/from cr/dr

The mov to/from cr/dr behave as if they were encoded with Mod = 3.  When
encoded with Mod != 3, no displacement or SIB bytes are fetched.

Add a test with a deliberately malformed ModRM byte.  (Also add the
automatically-generated simd.h to .gitignore.)

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
master commit: c2e316b2f220af06dab76b1219e61441c31f6ff9
master date: 2017-03-07 17:29:16 +0000

8 years agox86emul: correct decoding of vzero{all,upper}
Jan Beulich [Tue, 14 Mar 2017 11:42:58 +0000 (12:42 +0100)]
x86emul: correct decoding of vzero{all,upper}

These VEX encoded insns aren't followed by a ModR/M byte.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 26735f30dffe1091686bbe921aacbea8ba371cc8
master date: 2017-03-02 16:08:27 +0100

8 years agoxen: credit2: don't miss accounting while doing a credit reset.
Dario Faggioli [Tue, 14 Mar 2017 11:42:19 +0000 (12:42 +0100)]
xen: credit2: don't miss accounting while doing a credit reset.

A credit reset basically means going through all the
vCPUs of a runqueue and altering their credits, as a
consequence of a 'scheduling epoch' having come to an
end.

Blocked or runnable vCPUs are fine, all the credits
they've spent running so far have been accounted to
them when they were scheduled out.

But if a vCPU is running on a pCPU, when a reset event
occurs (on another pCPU), that does not get properly
accounted. Let's therefore begin to do so, for better
accuracy and fairness.

In fact, after this patch, we see this in a trace:

 csched2:schedule cpu 10, rq# 1, busy, not tickled
 csched2:burn_credits d1v5, credit = 9998353, delta = 202996
 runstate_continue d1v5 running->running
 ...
 csched2:schedule cpu 12, rq# 1, busy, not tickled
 csched2:burn_credits d1v6, credit = -1327, delta = 9999544
 csched2:reset_credits d0v13, credit_start = 10500000, credit_end = 10500000, mult = 1
 csched2:reset_credits d0v14, credit_start = 10500000, credit_end = 10500000, mult = 1
 csched2:reset_credits d0v7, credit_start = 10500000, credit_end = 10500000, mult = 1
 csched2:burn_credits d1v5, credit = 201805, delta = 9796548
 csched2:reset_credits d1v5, credit_start = 201805, credit_end = 10201805, mult = 1
 csched2:burn_credits d1v6, credit = -1327, delta = 0
 csched2:reset_credits d1v6, credit_start = -1327, credit_end = 9998673, mult = 1

Which shows how d1v5 actually executed for ~9.796 ms,
on pCPU 10, when reset_credit() is executed, on pCPU
12, because of d1v6's credits going below 0.

Without this patch, this 9.796ms are not accounted
to anyone. With this patch, d1v5 is charged for that,
and its credits drop down from 9796548 to 201805.

And this is important, as it means that it will
begin the new epoch with 10201805 credits, instead
of 10500000 (which he would have, before this patch).

Basically, we were forgetting one round of accounting
in epoch x, for the vCPUs that are running at the time
the epoch ends. And this meant favouring a little bit
these same vCPUs, in epoch x+1, providing them with
the chance of execute longer than their fair share.

Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
Reviewed-by: George Dunlap <george.dunlap@citrix.com>
master commit: 4fa4f8a3cd5afd4980ad9517755d002dc316abdc
master date: 2017-03-01 16:56:34 +0000

8 years agoxen: credit2: always mark a tickled pCPU as... tickled!
Dario Faggioli [Tue, 14 Mar 2017 11:41:54 +0000 (12:41 +0100)]
xen: credit2: always mark a tickled pCPU as... tickled!

In fact, whether or not a pCPU has been tickled, and is
therefore about to re-schedule, is something we look at
and base decisions on in various places.

So, let's make sure that we do that basing on accurate
information.

While there, also tweak a little bit smt_idle_mask_clear()
(used for implementing SMT support), so that it only alter
the relevant cpumask when there is the actual need for this.
(This is only for reduced overhead, behavior remains the
same).

Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
Reviewed-by: George Dunlap <george.dunlap@eu.citrix.com>
master commit: a76645240bd14e964e85dbc975a8989edea6aa27
master date: 2017-03-01 16:56:34 +0000

8 years agox86/layout: Correct Xen's idea of its own memory layout
Andrew Cooper [Tue, 14 Mar 2017 11:41:21 +0000 (12:41 +0100)]
x86/layout: Correct Xen's idea of its own memory layout

c/s b4cd59fe "x86: reorder .data and .init when linking" had an unintended
side effect, where xen_in_range() and the tboot S3 MAC were no longer correct.

In practice, it means that Xen's .data section is excluded from consideration,
which means:
 1) Default IOMMU construction for the hardware domain could create mappings.
 2) .data isn't included in the tboot MAC checked on resume from S3.

Adjust the comments and virtual address anchors used to define the regions.

Reported-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
master commit: c9a4a1c419cebac83a8fb60c4532ad8ccc973dc4
master date: 2017-02-28 16:18:38 +0000

8 years agox86/vmx: Don't leak host syscall MSR state into HVM guests
Andrew Cooper [Tue, 14 Mar 2017 11:40:36 +0000 (12:40 +0100)]
x86/vmx: Don't leak host syscall MSR state into HVM guests

hvm_hw_cpu->msr_flags is in fact the VMX dirty bitmap of MSRs needing to be
restored when switching into guest context.  It should never have been part of
the migration state to start with, and Xen must not make any decisions based
on the value seen during restore.

Identify it as obsolete in the header files, consistently save it as zero and
ignore it on restore.

The MSRs must be considered dirty during VMCS creation to cause the proper
defaults of 0 to be visible to the guest.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
master commit: 2f1add6e1c8789d979daaafa3d80ddc1bc375783
master date: 2017-02-21 11:06:39 +0000

8 years agoxen/arm: fix affected memory range by dcache clean functions
Stefano Stabellini [Fri, 3 Mar 2017 01:15:26 +0000 (17:15 -0800)]
xen/arm: fix affected memory range by dcache clean functions

clean_dcache_va_range and clean_and_invalidate_dcache_va_range don't
calculate the range correctly when "end" is not cacheline aligned. As a
result, the last cacheline is not skipped. Fix the issue by aligning the
start address to the cacheline size.

In addition, make the code simpler and faster in
invalidate_dcache_va_range, by removing the module operation and using
bitmasks instead. Also remove the size adjustments in
invalidate_dcache_va_range, because the size variable is not used later
on.

Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Reviewed-by: Julien Grall <julien.grall@arm.com>
Tested-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
8 years agoxen/arm: introduce vwfi parameter
Stefano Stabellini [Wed, 1 Mar 2017 19:43:15 +0000 (11:43 -0800)]
xen/arm: introduce vwfi parameter

Introduce new Xen command line parameter called "vwfi", which stands for
virtual wfi. The default is "trap": Xen traps guest wfi and wfe
instructions. In the case of wfi, Xen calls vcpu_block on the guest
vcpu; in the case of guest wfe, Xen calls vcpu_yield on the guest vcpu.
The behavior can be changed by setting vwfi to "native", in that case
Xen doesn't trap neither wfi nor wfe, running them in guest context.

The result is strong reduction in irq latency (from 5000ns to 2000ns,
measured using https://github.com/edgarigl/tbm, the physical timer, and
1 pcpu dedicated to 1 vcpu). The downside is that the scheduler thinks
that the guest is busy when actually is sleeping, leading to suboptimal
scheduling decisions.

Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Dario Faggioli <dario.faggioli@citrix.com>
Reviewed-by: Julien Grall <julien.grall@arm.com>
8 years agoarm/p2m: remove the page from p2m->pages list before freeing it
Julien Grall [Fri, 24 Feb 2017 09:01:59 +0000 (10:01 +0100)]
arm/p2m: remove the page from p2m->pages list before freeing it

The p2m code is using the page list field to link all the pages used
for the stage-2 page tables. The page is added into the p2m->pages
list just after the allocation but never removed from the list.

The page list field is also used by the allocator, not removing may
result a later Xen crash due to inconsistency (see [1]).

This bug was introduced by the reworking of p2m code in commit 2ef3e36ec7
"xen/arm: p2m: Introduce p2m_set_entry and __p2m_set_entry".

[1] https://lists.xenproject.org/archives/html/xen-devel/2017-02/msg00524.html

Reported-by: Vijaya Kumar K <Vijaya.Kumar@cavium.com>
Signed-off-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
master commit: cf5e1a74b9687be3d146e59ab10c26be6da9d0d4
master date: 2017-02-24 09:58:50 +0100

8 years agoQEMU_TAG update
Ian Jackson [Wed, 22 Feb 2017 16:26:41 +0000 (16:26 +0000)]
QEMU_TAG update

8 years agoVMX: fix VMCS race on context-switch paths
Jan Beulich [Mon, 20 Feb 2017 14:58:02 +0000 (15:58 +0100)]
VMX: fix VMCS race on context-switch paths

When __context_switch() is being bypassed during original context
switch handling, the vCPU "owning" the VMCS partially loses control of
it: It will appear non-running to remote CPUs, and hence their attempt
to pause the owning vCPU will have no effect on it (as it already
looks to be paused). At the same time the "owning" CPU will re-enable
interrupts eventually (the lastest when entering the idle loop) and
hence becomes subject to IPIs from other CPUs requesting access to the
VMCS. As a result, when __context_switch() finally gets run, the CPU
may no longer have the VMCS loaded, and hence any accesses to it would
fail. Hence we may need to re-load the VMCS in vmx_ctxt_switch_from().

For consistency use the new function also in vmx_do_resume(), to
avoid leaving an open-coded incarnation of it around.

Reported-by: Kevin Mayer <Kevin.Mayer@gdata.de>
Reported-by: Anshul Makkar <anshul.makkar@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Sergey Dyasli <sergey.dyasli@citrix.com>
Tested-by: Sergey Dyasli <sergey.dyasli@citrix.com>
master commit: 2f4d2198a9b3ba94c959330b5c94fe95917c364c
master date: 2017-02-17 15:49:56 +0100

8 years agoxen/p2m: Fix p2m_flush_table for non-nested cases
George Dunlap [Mon, 20 Feb 2017 14:57:37 +0000 (15:57 +0100)]
xen/p2m: Fix p2m_flush_table for non-nested cases

Commit 71bb7304e7a7a35ea6df4b0cedebc35028e4c159 added flushing of
nested p2m tables whenever the host p2m table changed.  Unfortunately
in the process, it added a filter to p2m_flush_table() function so
that the p2m would only be flushed if it was being used as a nested
p2m.  This meant that the p2m was not being flushed at all for altp2m
callers.

Only check np2m_base if p2m_class for nested p2m's.

NB that this is not a security issue: The only time this codepath is
called is in cases where either nestedp2m or altp2m is enabled, and
neither of them are in security support.

Reported-by: Matt Leinhos <matt@starlab.io>
Signed-off-by: George Dunlap <george.dunlap@citrix.com>
Reviewed-by: Tim Deegan <tim@xen.org>
Tested-by: Tamas K Lengyel <tamas@tklengyel.com>
master commit: 6192e6378e094094906950120470a621d5b2977c
master date: 2017-02-15 17:15:56 +0000

8 years agox86/ept: allow write-combining on !mfn_valid() MMIO mappings again
David Woodhouse [Mon, 20 Feb 2017 14:56:48 +0000 (15:56 +0100)]
x86/ept: allow write-combining on !mfn_valid() MMIO mappings again

For some MMIO regions, such as those high above RAM, mfn_valid() will
return false.

Since the fix for XSA-154 in commit c61a6f74f80e ("x86: enforce
consistent cachability of MMIO mappings"), guests have no longer been
able to use PAT to obtain write-combining on such regions because the
'ignore PAT' bit is set in EPT.

We probably want to err on the side of caution and preserve that
behaviour for addresses in mmio_ro_ranges, but not for normal MMIO
mappings. That necessitates a slight refactoring to check mfn_valid()
later, and let the MMIO case get through to the right code path.

Since we're not bailing out for !mfn_valid() immediately, the range
checks need to be adjusted to cope \97 simply by masking in the low bits
to account for 'order' instead of adding, to avoid overflow when the mfn
is INVALID_MFN (which happens on unmap, since we carefully call this
function to fill in the EMT even though the PTE won't be valid).

The range checks are also slightly refactored to put only one of them in
the fast path in the common case. If it doesn't overlap, then it
*definitely* isn't contained, so we don't need both checks. And if it
overlaps and is only one page, then it definitely *is* contained.

Finally, add a comment clarifying how that 'return -1' works \97 it isn't
returning an error and causing the mapping to fail; it relies on
resolve_misconfig() being able to split the mapping later. So it's
*only* sane to do it where order>0 and the 'problem' will be solved by
splitting the large page. Not for blindly returning 'error', which I was
tempted to do in my first attempt.

Signed-off-by: David Woodhouse <dwmw@amazon.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
master commit: 30921dc2df3665ca1b2593595aa6725ff013d386
master date: 2017-02-07 14:30:01 +0100

8 years agoIOMMU: always call teardown callback
Oleksandr Tyshchenko [Wed, 15 Feb 2017 12:20:48 +0000 (12:20 +0000)]
IOMMU: always call teardown callback

There is a possible scenario when (d)->need_iommu remains unset
during guest domain execution. For example, when no devices
were assigned to it. Taking into account that teardown callback
is not called when (d)->need_iommu is unset we might have unreleased
resourses after destroying domain.

So, always call teardown callback to roll back actions
that were performed in init callback.

This is XSA-207.

Signed-off-by: Oleksandr Tyshchenko <olekstysh@gmail.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Tested-by: Jan Beulich <jbeulich@suse.com>
Tested-by: Julien Grall <julien.grall@arm.com>
8 years agox86/emulate: don't assume that addr_size == 32 implies protected mode
George Dunlap [Thu, 9 Feb 2017 09:25:58 +0000 (10:25 +0100)]
x86/emulate: don't assume that addr_size == 32 implies protected mode

Callers of x86_emulate() generally define addr_size based on the code
segment.  In vm86 mode, the code segment is set by the hardware to be
16-bits; but it is entirely possible to enable protected mode, set the
CS to 32-bits, and then disable protected mode.  (This is commonly
called "unreal mode".)

But the instruction decoder only checks for protected mode when
addr_size == 16.  So in unreal mode, hardware will throw a #UD for VEX
prefixes, but our instruction decoder will decode them, triggering an
ASSERT() further on in _get_fpu().  (With debug=n the emulator will
incorrectly emulate the instruction rather than throwing a #UD, but
this is only a bug, not a crash, so it's not a security issue.)

Teach the instruction decoder to check that we're in protected mode,
even if addr_size is 32.

Signed-off-by: George Dunlap <george.dunlap@citrix.com>
Split real mode and VM86 mode handling, as VM86 mode is strictly 16-bit
at all times. Re-base.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 05118b1596ffe4559549edbb28bd0124a7316123
master date: 2017-01-25 15:09:55 +0100

8 years agoxen: credit2: fix shutdown/suspend when playing with cpupools.
Dario Faggioli [Thu, 9 Feb 2017 09:25:33 +0000 (10:25 +0100)]
xen: credit2: fix shutdown/suspend when playing with cpupools.

In fact, during shutdown/suspend, we temporarily move all
the vCPUs to the BSP (i.e., pCPU 0, as of now). For Credit2
domains, we call csched2_vcpu_migrate(), expects to find the
target pCPU in the domain's pool

Therefore, if Credit2 is the default scheduler and we have
removed pCPU 0 from cpupool0, shutdown/suspend fails like
this:

 RIP:    e008:[<ffff82d08012906d>] sched_credit2.c#migrate+0x274/0x2d1
 Xen call trace:
    [<ffff82d08012906d>] sched_credit2.c#migrate+0x274/0x2d1
    [<ffff82d080129138>] sched_credit2.c#csched2_vcpu_migrate+0x6e/0x86
    [<ffff82d08012c468>] schedule.c#vcpu_move_locked+0x69/0x6f
    [<ffff82d08012ec14>] cpu_disable_scheduler+0x3d7/0x430
    [<ffff82d08019669b>] __cpu_disable+0x299/0x2b0
    [<ffff82d0801012f8>] cpu.c#take_cpu_down+0x2f/0x38
    [<ffff82d0801312d8>] stop_machine.c#stopmachine_action+0x7f/0x8d
    [<ffff82d0801330b8>] tasklet.c#do_tasklet_work+0x74/0xab
    [<ffff82d0801333ed>] do_tasklet+0x66/0x8b
    [<ffff82d080166a73>] domain.c#idle_loop+0x3b/0x5e

 ****************************************
 Panic on CPU 8:
 Assertion 'svc->vcpu->processor < nr_cpu_ids' failed at sched_credit2.c:1729
 ****************************************

On the other hand, if Credit2 is the scheduler of another
pool, when trying (still during shutdown/suspend) to move
the vCPUs of the Credit2 domains to pCPU 0, it figures
out that pCPU 0 is not a Credit2 pCPU, and fails like this:

 RIP:    e008:[<ffff82d08012916b>] sched_credit2.c#csched2_vcpu_migrate+0xa1/0x107
 Xen call trace:
    [<ffff82d08012916b>] sched_credit2.c#csched2_vcpu_migrate+0xa1/0x107
    [<ffff82d08012c4e9>] schedule.c#vcpu_move_locked+0x69/0x6f
    [<ffff82d08012edfc>] cpu_disable_scheduler+0x3d7/0x430
    [<ffff82d08019687b>] __cpu_disable+0x299/0x2b0
    [<ffff82d0801012f8>] cpu.c#take_cpu_down+0x2f/0x38
    [<ffff82d0801314c0>] stop_machine.c#stopmachine_action+0x7f/0x8d
    [<ffff82d0801332a0>] tasklet.c#do_tasklet_work+0x74/0xab
    [<ffff82d0801335d5>] do_tasklet+0x66/0x8b
    [<ffff82d080166c53>] domain.c#idle_loop+0x3b/0x5e

The solution is to recognise the specific situation, inside
csched2_vcpu_migrate() and, considering it is something temporary,
which only happens during shutdown/suspend, quickly deal with it.

Then, in the resume path, in restore_vcpu_affinity(), things
are set back to normal, and a new v->processor is chosen, for
each vCPU, from the proper set of pCPUs (i.e., the ones of
the proper cpupool).

Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
Acked-by: George Dunlap <george.dunlap@citrix.com>
xen: credit2: non Credit2 pCPUs are ok during shutdown/suspend.

Commit 7478ebe1602e6 ("xen: credit2: fix shutdown/suspend
when playing with cpupools"), while doing the right thing
for actual code, forgot to update the ASSERT()s accordingly,
in csched2_vcpu_migrate().

In fact, as stated there already, during shutdown/suspend,
we must allow a Credit2 vCPU to temporarily migrate to a
non Credit2 BSP, without any ASSERT() triggering.

Move them down, after the check for whether or not we are
shutting down, where the assumption that the pCPU must be
valid Credit2 ones, is valid.

Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
master commit: 7478ebe1602e6bb8242a18840b15757a1d5ad18a
master date: 2017-01-24 17:02:07 +0000
master commit: ad5808d9057248e7879cf375662f0a449fff7005
master date: 2017-02-01 14:44:51 +0000

8 years agoxen: credit2: never consider CPUs outside of our cpupool.
Dario Faggioli [Thu, 9 Feb 2017 09:24:56 +0000 (10:24 +0100)]
xen: credit2: never consider CPUs outside of our cpupool.

In fact, relying on the mask of what pCPUs belong to
which Credit2 runqueue is not enough. If we only do that,
when Credit2 is the boot scheduler, we may ASSERT() or
panic when moving a pCPU from Pool-0 to another cpupool.

This is because pCPUs outside of any pool are considered
part of cpupool0. This puts us at risk of crash when those
same pCPUs are added to another pool and something
different than the idle domain is found to be running
on them.

Note that, even if we prevent the above to happen (which
is the purpose of this patch), this is still pretty bad,
in fact, when we remove a pCPU from Pool-0:
- in Credit1, as we do *not* update prv->ncpus and
  prv->credit, which means we're considering the wrong
  total credits when doing accounting;
- in Credit2, the pCPU remains part of one runqueue,
  and is hence at least considered during load balancing,
  even if no vCPU should really run there.

In Credit1, this "only" causes skewed accounting and
no crashes because there is a lot of `cpumask_and`ing
going on with the cpumask of the domains' cpupool
(which, BTW, comes at a price).

A quick and not to involved (and easily backportable)
solution for Credit2, is to do exactly the same.

Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com
Acked-by: George Dunlap <george.dunlap@citrix.com>
master commit: e7191920261d20e52ca4c06a03589a1155981b04
master date: 2017-01-24 17:02:07 +0000

8 years agoxen: credit2: use the correct scratch cpumask.
Dario Faggioli [Thu, 9 Feb 2017 09:24:32 +0000 (10:24 +0100)]
xen: credit2: use the correct scratch cpumask.

In fact, there is one scratch mask per each CPU. When
you use the one of a CPU, it must be true that:
 - the CPU belongs to your cpupool and scheduler,
 - you own the runqueue lock (the one you take via
   {v,p}cpu_schedule_lock()) for that CPU.

This was not the case within the following functions:

get_fallback_cpu(), csched2_cpu_pick(): as we can't be
sure we either are on, or hold the lock for, the CPU
that is in the vCPU's 'v->processor'.

migrate(): it's ok, when called from balance_load(),
because that comes from csched2_schedule(), which takes
the runqueue lock of the CPU where it executes. But it is
not ok when we come from csched2_vcpu_migrate(), which
can be called from other places.

The fix is to explicitly use the scratch space of the
CPUs for which we know we hold the runqueue lock.

Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
Reported-by: Jan Beulich <JBeulich@suse.com>
Reviewed-by: George Dunlap <george.dunlap@citrix.com>
master commit: 548db8742872399936a2090cbcdfd5e1b34fcbcc
master date: 2017-01-24 17:02:07 +0000

8 years agox86/hvm: do not set msr_tsc_adjust on hvm_set_guest_tsc_fixed
Joao Martins [Thu, 9 Feb 2017 09:23:52 +0000 (10:23 +0100)]
x86/hvm: do not set msr_tsc_adjust on hvm_set_guest_tsc_fixed

Commit 6e03363 ("x86: Implement TSC adjust feature for HVM guest")
implemented TSC_ADJUST MSR for hvm guests. Though while booting
an HVM guest the boot CPU would have a value set with delta_tsc -
guest tsc while secondary CPUS would have 0. For example one can
observe:
 $ xen-hvmctx 17 | grep tsc_adjust
 TSC_ADJUST: tsc_adjust ff9377dfef47fe66
 TSC_ADJUST: tsc_adjust 0
 TSC_ADJUST: tsc_adjust 0
 TSC_ADJUST: tsc_adjust 0

Upcoming Linux 4.10 now validates whether this MSR is correct and
adjusts them accordingly under the following conditions: values of < 0
(our case for CPU 0) or != 0 or values > 7FFFFFFF. In this conditions it
will force set to 0 and for the CPUs that the value doesn't match all
together. If this msr is not correct we would see messages such as:

[Firmware Bug]: TSC ADJUST: CPU0: -30517044286984129 force to 0

And on HVM guests supporting TSC_ADJUST (requiring at least Haswell
Intel) it won't boot.

Our current vCPU 0 values are incorrect and according to Intel SDM which on
section "Time-Stamp Counter Adjustment" states that "On RESET, the value
of the IA32_TSC_ADJUST MSR is 0." hence we should set it 0 and be
consistent across multiple vCPUs. Perhaps this MSR should be only
changed by the guest which already happens through
hvm_set_guest_tsc_adjust(..) routines (see below). After this patch
guests running Linux 4.10 will see a valid IA32_TSC_ADJUST msr of value
 0 for all CPUs and are able to boot.

On the same section of the spec ("Time-Stamp Counter Adjustment") it is
also stated:
"If an execution of WRMSR to the IA32_TIME_STAMP_COUNTER MSR
 adds (or subtracts) value X from the TSC, the logical processor also
 adds (or subtracts) value X from the IA32_TSC_ADJUST MSR.

 Unlike the TSC, the value of the IA32_TSC_ADJUST MSR changes only in
 response to WRMSR (either to the MSR itself, or to the
 IA32_TIME_STAMP_COUNTER MSR). Its value does not otherwise change as
 time elapses. Software seeking to adjust the TSC can do so by using
 WRMSR to write the same value to the IA32_TSC_ADJUST MSR on each logical
 processor."

This suggests these MSRs values should only be changed through guest i.e.
throught write intercept msrs. We keep IA32_TSC MSR logic such that writes
accomodate adjustments to TSC_ADJUST, hence no functional change in the
msr_tsc_adjust for IA32_TSC msr. Though, we do that in a separate routine
namely hvm_set_guest_tsc_msr instead of through hvm_set_guest_tsc(...).

Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
master commit: 98297f09bd07bb63407909aae1d309d8adeb572e
master date: 2017-01-24 12:37:36 +0100

8 years agox86emul: correct FPU stub asm() constraints
Jan Beulich [Thu, 9 Feb 2017 09:23:22 +0000 (10:23 +0100)]
x86emul: correct FPU stub asm() constraints

Properly inform the compiler about fic's role as both an input (its
insn_bytes field) and output (its exn_raised field).

Take the opportunity and bring emulate_fpu_insn_stub() more in line
with emulate_fpu_insn_stub_eflags().

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 3dfbb8df335f12297cfc7db9d3df2b74c474921b
master date: 2017-01-24 12:35:59 +0100

8 years agox86: segment attribute handling adjustments
Jan Beulich [Thu, 9 Feb 2017 09:22:55 +0000 (10:22 +0100)]
x86: segment attribute handling adjustments

Null selector loads into SS (possible in 64-bit mode only, and only in
rings other than ring 3) must not alter SS.DPL. (This was found to be
an issue on KVM, and fixed in Linux commit 33ab91103b.)

Further arch_set_info_hvm_guest() didn't make sure that the ASSERT()s
in hvm_set_segment_register() wouldn't trigger: Add further checks, but
tolerate (adjust) clear accessed (CS, SS, DS, ES) and busy (TR) bits.

Finally the setting of the accessed bits for user segments was lost by
commit dd5c85e312 ("x86/hvm: Reposition the modification of raw segment
data from the VMCB/VMCS"), yet VMX requires them to be set for usable
segments. Add respective ASSERT()s (the only path not properly setting
them was arch_set_info_hvm_guest()).

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 366ff5f1b3252f9069d5aedb2ffc2567bb0a37c9
master date: 2017-01-20 14:39:12 +0100

8 years agox86emul: LOCK check adjustments
Jan Beulich [Thu, 9 Feb 2017 09:22:28 +0000 (10:22 +0100)]
x86emul: LOCK check adjustments

BT, being encoded as DstBitBase just like BT{C,R,S}, nevertheless does
not write its (register or memory) operand and hence also doesn't allow
a LOCK prefix to be used.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: f2d4f4ba80de8a03a1b0f300d271715a88a8433d
master date: 2017-01-20 14:37:33 +0100

8 years agox86emul: VEX.B is ignored in compatibility mode
Jan Beulich [Thu, 9 Feb 2017 09:21:50 +0000 (10:21 +0100)]
x86emul: VEX.B is ignored in compatibility mode

While VEX.R and VEX.X are guaranteed to be 1 in compatibility mode
(and hence a respective mode_64bit() check can be dropped), VEX.B can
be encoded as zero, but would be ignored by the processor. Since we
emulate instructions in 64-bit mode (except possibly in the test
harness), we need to force the bit to 1 in order to not act on the
wrong {X,Y,Z}MM register (which has no bad effect on 32-bit test
harness builds, as there the bit would again be ignored by the
hardware, and would by default be expected to be 1 anyway).

We must not, however, fiddle with the high bit of VEX.VVVV in the
decode phase, as that would undermine the checking of instructions
requiring the field to be all ones independent of mode. This is
being enforced in copy_REX_VEX() instead.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
x86emul: correct VEX/XOP/EVEX operand size handling for 16-bit code

Operand size defaults to 32 bits in that case, but would not have been
set that way in the absence of an operand size override.

Reported-by: Wei Liu <wei.liu2@citrix.com> (by AFL fuzzing)
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 89c76ee7f60777b81c8fd0475a6af7c84e72a791
master date: 2017-01-17 10:32:25 +0100
master commit: beb82042447c5d6e7073d816d6afc25c5a423cde
master date: 2017-01-25 15:08:59 +0100

8 years agox86/xstate: Fix array overrun on hardware with LWP
Andrew Cooper [Thu, 9 Feb 2017 09:20:45 +0000 (10:20 +0100)]
x86/xstate: Fix array overrun on hardware with LWP

c/s da62246e4c "x86/xsaves: enable xsaves/xrstors/xsavec in xen" introduced
setup_xstate_features() to allocate and fill xstate_offsets[] and
xstate_sizes[].

However, fls() casts xfeature_mask to 32bits which truncates LWP out of the
calculation.  As a result, the arrays are allocated too short, and the cpuid
infrastructure reads off the end of them when calculating xstate_size for the
guest.

On one test system, this results in 0x3fec83c0 being returned as the maximum
size of an xsave area, which surprisingly appears not to bother Windows or
Linux too much.  I suspect they both use current size based on xcr0, which Xen
forwards from real hardware.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
master commit: fe0d67576e335c02becf1cea8e67005509fa90b6
master date: 2017-01-16 17:37:26 +0000

8 years agoarm/p2m: Fix regression during domain shutdown with active mem_access
Tamas K Lengyel [Wed, 25 Jan 2017 16:12:01 +0000 (09:12 -0700)]
arm/p2m: Fix regression during domain shutdown with active mem_access

The change in commit 438c5fe4f0c introduced a regression for domains where
mem_acces is or was active. When relinquish_p2m_mapping attempts to clear
a page where the order is not 0 the following ASSERT is triggered:

    ASSERT(!p2m->mem_access_enabled || page_order == 0);

This regression was unfortunately not caught during testing in preparation
for the 4.8 release.

In this patch we adjust the ASSERT to not trip when the domain
is being shutdown.

Signed-off-by: Tamas K Lengyel <tamas.lengyel@zentific.com>
Acked-by: Julien Grall <julien.grall@arm.com>
8 years agolibxl: fix libxl_set_memory_target
Wei Liu [Thu, 29 Dec 2016 16:36:31 +0000 (16:36 +0000)]
libxl: fix libxl_set_memory_target

Commit 26dbc93a ("libxl: Remove pointless hypercall from
libxl_set_memory_target") removed the call to xc_domain_getinfolist, but
it failed to notice that "info" was actually needed later.

Put that back. While at it, make the code conform to coding style
requirement.

Reported-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
(cherry picked from commit ed5f19aea66fe5a72060d6a795ffcd23b7643ee3)

8 years agoxen/arm: gic-v3: Make sure read from ICC_IAR1_EL1 is visible on the redistributor
Julien Grall [Wed, 18 Jan 2017 18:54:08 +0000 (18:54 +0000)]
xen/arm: gic-v3: Make sure read from ICC_IAR1_EL1 is visible on the redistributor

"The effects of reading ICC_IAR0_EL1 and ICC_IAR1_EL1 on the state of a
returned INTID are not guaranteed to be visible until after the execution
of a DSB".

Because of the GIC is an external component, a dsb sy is required.
Without it the sysreg read may not have been made visible on the
redistributor.

Signed-off-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
8 years agox86/cpu: Don't update this_cpu for get_cpu_vendor(, gcv_guest)
Andrew Cooper [Wed, 18 Jan 2017 08:52:19 +0000 (09:52 +0100)]
x86/cpu: Don't update this_cpu for get_cpu_vendor(, gcv_guest)

Otherwise booting a cross-vendor guest would cause PCPU hotplug to
malfunction, because of trying to use the wrong CPU driver.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
master commit: 291dcb4dd0140fac0e439760b4d51b2892ff9264
master date: 2017-01-03 13:33:16 +0000

8 years agox86/emul: Correct the return value handling of VMFUNC
Andrew Cooper [Wed, 18 Jan 2017 08:51:53 +0000 (09:51 +0100)]
x86/emul: Correct the return value handling of VMFUNC

The bracketing of x86_emulate() calling the ops->vmfunc() hook is wrong with
respect to the assignment to rc, which can trip the new assertions in
x86_emulate_wrapper().

The hvmemul_vmfunc() hook should only raise #UD if X86EMUL_EXCEPTION is
returned.  This is only a latent bug at the moment.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
master commit: 3ab1876504d409689824e161a8b04e57e1e5dd46
master date: 2016-12-22 13:32:46 +0000

8 years agox86/boot: fix build with certain older gcc versions
Jan Beulich [Wed, 18 Jan 2017 08:49:55 +0000 (09:49 +0100)]
x86/boot: fix build with certain older gcc versions

Despite all attempts so far (ending in commit fecf584294 ["Config.mk:
fix comment for debug option"] adjusting the respective comment),
Config.mk's debug= setting still affects the hypervisor build: CFLAGS
gets -g added there.

xen/arch/x86/boot/build32.mk includes that file, and hence inherits the
setting too. Some gcc versions take -g to create an .eh_frame section
despite -fno-asynchronous-unwind-tables (which instead one would expect
to produce .debug_frame).

In turn, commit 93c0c0287a ("x86/boot: create *.lnk files with linker
script") was - in my understanding - supposed to make sure .text is
first, but apparently it did also not really achieve that effect: Both
reloc.lnk and reloc.bin in the case here ended up with .eh_frame first,
which obviously rendered the whole final binary unusable.

Explicitly suppress generation of any kind of debug info when building
reloc.o.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 620b3c7eee78e90167f591877177c922ae619b92
master date: 2016-12-16 14:37:35 +0100

8 years agox86emul: CMPXCHG16B requires an aligned operand
Jan Beulich [Wed, 18 Jan 2017 08:49:26 +0000 (09:49 +0100)]
x86emul: CMPXCHG16B requires an aligned operand

This distinguishes it from CMPXCHG8B.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: d7d3a82c28a1102ee6c9707071a946164bae0d57
master date: 2016-12-16 14:37:11 +0100

8 years agoVT-d: correct dma_msi_set_affinity()
Jan Beulich [Wed, 18 Jan 2017 08:48:57 +0000 (09:48 +0100)]
VT-d: correct dma_msi_set_affinity()

Commit 83cd2038fe ("VT-d: use msi_compose_msg()) together with
15aa6c6748 ("amd iommu: use base platform MSI implementation"),
introducing the use of a per-CPU scratch CPU mask, went too far:
dma_msi_set_affinity() may, at least in theory, be called in
interrupt context, and hence the use of that scratch variable is not
correct.

Since the function overwrites the destination information anyway,
allow msi_compose_msg() to be called with a NULL CPU mask, avoiding
the use of that scratch variable.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 7f885a1f49a75c770360b030666a5c1545156e5c
master date: 2016-12-16 14:33:43 +0100

8 years agox86emul: ignore most segment bases for 64-bit mode in is_aligned()
Jan Beulich [Wed, 18 Jan 2017 08:48:23 +0000 (09:48 +0100)]
x86emul: ignore most segment bases for 64-bit mode in is_aligned()

ops->read_segment() will report whatever is actually there in the
register, so we need to actively distinguish ES/CS/SS/DS from FS/GS.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 6e616a3cef4d782253787904bf3d641112eafa14
master date: 2016-12-15 11:13:32 +0100

8 years agox86emul: MOVNTI does not allow REP prefixes
Jan Beulich [Wed, 18 Jan 2017 08:47:31 +0000 (09:47 +0100)]
x86emul: MOVNTI does not allow REP prefixes

Just like 66, prefixes F3 and F2 cause #UD.

Also adjust a related comment, which in its previous wording was
misleading (as in 16-bit mode there would nothing be undone when
adjusting operand size from 2 to 4).

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 96a7cb37b921d2b320183d194d143262e1dd5b53
master date: 2016-12-14 10:11:08 +0100

8 years agox86/VPMU: clear the overflow status of which counter happened to overflow
Luwei Kang [Wed, 18 Jan 2017 08:46:54 +0000 (09:46 +0100)]
x86/VPMU: clear the overflow status of which counter happened to overflow

Just set the corresponding bits of counters which happened to overflow,
rather than setting all the available bits of IA32_PERF_GLOBAL_OVF_CTRL
when pmu interrupt happened.

Signed-off-by: Luwei Kang <luwei.kang@intel.com>
Acked-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
master commit: 7a0c70482580234868fcc53b8d72e31966dc7c52
master date: 2016-12-13 14:21:26 +0100

8 years agox86/hvm: don't unconditionally create a default ioreq server
Paul Durrant [Wed, 18 Jan 2017 08:46:26 +0000 (09:46 +0100)]
x86/hvm: don't unconditionally create a default ioreq server

Avoid doing so if the domain is not under construction.

If upstream QEMU is in use then it will explicitly create an ioreq server
rather than implicitly creating the default ioreq server, which is a
side-effect of reading HVM_PARAM_IOREQ_PFN, HVM_PARAM_BUFIOREQ_PFN,
or HVM_PARAM_BUFIOREQ_EVTCHN (as is done by legacy QEMUs).

However, if the domain is subsequently saved/migrated then those parameters
are read and hence the default server will be unnecessarily instantiated.

This patch adds an extra check of the 'creation_finished' flag when those
HVM params are read and will only instantiate the server if the domain is
under construction, which will always be the case when QEMU is invoked.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Tested-by: Zhang Chen <zhangchen.fnst@cn.fujitsu.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
x86/hvm: Fix HVMOP_get_param when skipping creating the default ioreq server

c/s e7dabe5 "x86/hvm: don't unconditionally create a default ioreq server"
added a break statement, but the logic previously depended on falling through
into the default case to fill in the value the caller asked for.

This causes the sending migration code to put a junk PARAM into the stream,
and the receiving side to fail to zero the IOREQ pages, causing QEMU to object
when it finds stale requests while starting up.

Reorder the code so it more clearly falls through into the default case.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
master commit: e7dabe59c3239dc9ef9edbc49ed54f754616ebf7
master date: 2016-12-12 09:49:10 +0100
master commit: 451c9938c68ccb77ff94765f7ac47e8de51d3f43
master date: 2016-12-13 09:58:33 +0000

8 years agolibelf: section index 0 is special
Jan Beulich [Wed, 18 Jan 2017 08:45:54 +0000 (09:45 +0100)]
libelf: section index 0 is special

When iterating over sections, table entry zero needs to be ignored.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
master commit: 41fe9cabf29ea15c1f8edee49326dfde705013d3
master date: 2016-12-07 13:52:35 +0100

8 years agox86emul: CMPXCHG{8,16}B ignore prefixes
Jan Beulich [Wed, 18 Jan 2017 08:44:49 +0000 (09:44 +0100)]
x86emul: CMPXCHG{8,16}B ignore prefixes

This removes 0F C7 from the list of two-byte opcodes treating prefixes
66, F3, and F2 as opcode extensions. We better manually handle this in
the opcode specific code:
- CMPXCHG8B ignores all these prefixes (its handling is being adjusted
  accordingly, with a respective test case added as well, to avoid
  re-introducing the subject of XSA-200),
- RDRAND/RDSEED (support to be added subsequently) honor 66, but treat
  F3 and F2 as opcode extensions (resolving to RDPID in the RDSEED
  case, which in turn ignores 66).

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 54abe826c8297e12f805be2bcf318ef75cc7f58d
master date: 2016-12-14 10:08:22 +0100

8 years agoxen: Fix determining when domain creation is complete
Andrew Cooper [Wed, 18 Jan 2017 08:43:47 +0000 (09:43 +0100)]
xen: Fix determining when domain creation is complete

d->creation_finished is used in several places alter behaviour depending on
whether the domain is being created, or is already running.

However, there is a latent bug if a toolstack component makes a pair of
pause/unpause calls, where creation will be considered finished prematurely.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Tested-by: Paul Durrant <paul.durrant@citrix.com>
master commit: 9d71e02e8420b5d4a48d92446a1edbff498ee1c6
master date: 2016-12-13 09:58:33 +0000

8 years agox86emul: correct PUSHF/POPF
Jan Beulich [Wed, 18 Jan 2017 08:43:00 +0000 (09:43 +0100)]
x86emul: correct PUSHF/POPF

Both need to raise #GP(0) when in VM86 mode with IOPL < 3.

Additionally PUSHF is documented to clear VM and RF from the value
placed onto the stack.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: e5c1b8145bccb7fc587ee5b0c95ace6c5e0c7ffd
master date: 2016-12-07 13:55:42 +0100

8 years agoinit/FreeBSD: fix incorrect usage of $rc_pids in xendriverdomain
Roger Pau Monne [Wed, 21 Dec 2016 16:47:26 +0000 (16:47 +0000)]
init/FreeBSD: fix incorrect usage of $rc_pids in xendriverdomain

It should be rc_pid.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reported-by: Nathan Friess <nathan.friess@gmail.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
(cherry picked from commit fb4c92ffa661516e41d24974d3d0a2a3608caf68)

8 years agoinit/FreeBSD: add rc control variables
Roger Pau Monne [Mon, 19 Dec 2016 15:02:04 +0000 (15:02 +0000)]
init/FreeBSD: add rc control variables

Those are used in order to decide which scripts are executed at init.

Ref: https://www.freebsd.org/doc/en/articles/rc-scripting/article.html#rcng-confdummy

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
[ wei: fix up conflict ]
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
(cherry picked from commit 4d362ce02aaf1699957fb7c0edc6ae5839ccb30e)

8 years agoinit/FreeBSD: fix xencommons so it can only be launched by Dom0
Roger Pau Monne [Mon, 19 Dec 2016 15:02:03 +0000 (15:02 +0000)]
init/FreeBSD: fix xencommons so it can only be launched by Dom0

At the moment the execution of xencommons is gated on the presence of the
privcmd device, but that's not correct, since privcmd is available to all Xen
domains (privileged or unprivileged). Instead of using privcmd use the
xenstored device, which will only be available to the domain that's in charge
of running xenstored, and thus xencommons.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
(cherry picked from commit c875b9778da0c56a0c118626771465b87df31fe8)

8 years agoinit/FreeBSD: remove xendriverdomain_precmd
Roger Pau Monne [Mon, 19 Dec 2016 15:02:02 +0000 (15:02 +0000)]
init/FreeBSD: remove xendriverdomain_precmd

...because it's empty. While there also rename xendriverdomain_startcmd to
xendriverdomain_start in order to match the nomenclature of the file.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
[ wei: fix up minor error ]
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
(cherry picked from commit 29b968e46b215bea8881abdfd06a046417b83006)

8 years agoinit/FreeBSD: set correct PATH for xl devd
Roger Pau Monne [Mon, 19 Dec 2016 15:02:01 +0000 (15:02 +0000)]
init/FreeBSD: set correct PATH for xl devd

FreeBSD init scripts don't have /usr/local/{bin/sbin} in it's PATH, which
prevents `xl devd` from working properly since hotplug scripts require the set
of xenstore cli tools to be in PATH.

While there also fix the usage of --pidfile, which according to the xl help
doesn't use "=", and add braces around XLDEVD_PIDFILE.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
(cherry picked from commit 1d52073334d7615934fe804bc656b7aab0e92ebd)

8 years agoxsm: allow relevant permission during migrate and gpu-passthrough.
Anshul Makkar [Mon, 12 Dec 2016 14:00:05 +0000 (14:00 +0000)]
xsm: allow relevant permission during migrate and gpu-passthrough.

During guest migrate allow permission to prevent
spurious page faults.
Prevents these errors:
d73: Non-privileged (73) attempt to map I/O space 00000000

avc: denied  { set_misc_info } for domid=0 target=11
scontext=system_u:system_r:dom0_t
tcontext=system_u:system_r:domU_t tclass=domain

GPU passthrough for hvm guest:
avc:  denied  { send_irq } for domid=0 target=10
scontext=system_u:system_r:dom0_t
tcontext=system_u:system_r:domU_t tclass=hvm

Signed-off-by: Anshul Makkar <anshul.makkar@citrix.com>
Acked-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
(cherry picked from commit f04722f78b0f64e1f147389962d8f393a2fa8a7a)

8 years agolibxl: init_acpi_config should return rc in exit path, and set to 0 on success
Wei Liu [Wed, 14 Dec 2016 11:44:36 +0000 (11:44 +0000)]
libxl: init_acpi_config should return rc in exit path, and set to 0 on success

init_acpi_config should return rc in exit path

... otherwise it returns 0 even if the function fails.

Coverity-ID: 1397121

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
(cherry picked from commit 1361db0ed3ad1217bd039a3cac5df49a622e12a9)

AND:

set rc to 0 in init_acpi_config in success path

xc_doamin_getinfo returns >=0 in success path, and if there is no vnode
configured, that rc will be returned to caller, which indicates error.

Fix that by setting rc to 0 in success path.

Reported-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
(cherry picked from commit 08ccb46924385c833bd0da9e087fb6b96fa76849)

Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
8 years agox86/emul: add likely()/unlikely() to test harness
Andrew Cooper [Thu, 22 Dec 2016 15:23:37 +0000 (16:23 +0100)]
x86/emul: add likely()/unlikely() to test harness

Fix a build problem introduced in c/s 122dd9575c7 "x86emul:
in_longmode() should not ignore ->read_msr() errors" by providing an
implementation of likely()/unlikely().

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Cherrypicked out of:

master commit: 3e84c8da7d2c5442a12789dae7163dca6c0e154f
master date: 2016-12-02 17:23:01 +0000

8 years agox86/HVM: add missing NULL check before using VMFUNC hook
Jan Beulich [Wed, 21 Dec 2016 16:41:20 +0000 (17:41 +0100)]
x86/HVM: add missing NULL check before using VMFUNC hook

This is CVE-2016-10025 / XSA-203.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 74dcd0ce6f4fadce8093e54f0fc1a45426577e13
master date: 2016-12-21 16:47:19 +0100