While I did review d0a699a389 ("x86/monitor: add support for descriptor
access events") it didn't really occur to me that someone could be this
blunt and add unguarded emulation again just a few weeks after we
guarded all special purpose emulator invocations. Fix this.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-acked-by: Julien Grall <julien.grall@arm.com>
The function is rather unlikely to be called for insns which don't have
ModRM bytes, and hence addressing Coverity's recurring complaint of
callers potentially consuming uninitialized data when they know that
certain opcodes have ModRM bytes can be suppressed this way without
unduly adding overhead to fast paths.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-acked-by: Julien Grall <julien.grall@arm.com>
No matter that we emulate IRET for (guest) real mode only right now, we
should get its effect on (virtual) NMI delivery right. Note that we can
simply check the other retire flags also in the !OKAY case, as the
insn emulator now guarantees them to only be set on OKAY.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
Release-acked-by: Julien Grall <julien.grall@arm.com>
No quote is required when a string is provided as part of a spec string.
Reported-by: Doug Freed <dwfreed@mtu.edu>
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Since c/s 92cf67888a, x86_emulate_wrapper() asserts stricter behaviour about
the relationship between X86EMUL_EXCEPTION and ctxt.event_pending.
These removals should have been included in the aforementioned changeset, and
were only omitted due an oversight.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Acked-by: Tim Deegan <tim@xen.org>
Release-acked-by: Julien Grall <julien.grall@arm.com>
In a release build modern gcc validly complains about "pin" possibly
being uninitialized in vioapic_irq_positive_edge().
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-acked-by: Julien Grall <julien.grall@arm.com>
Fix two flaws in the patch (93358e8e VT-d: introduce update_irte to update
irte safely):
1. Expand a comment in update_irte() to make it clear that VT-d hardware
doesn't update IRTE and software can't update IRTE behind us since we hold
iremap_lock.
2. remove an useless if() statement
Signed-off-by: Chao Gao <chao.gao@intel.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Kevin Tian <kevin.tian@intel.com>
Release-acked-by: Julien Grall <julien.grall@arm.com>
clang gcc-compat warnings can wrongly fire when certain constructions are used,
at least the following flow:
switch ( ... )
{
case ...:
while ( ({ int x; switch ( foo ) { case 1: x = 1; break; } x }) )
{
...
Will cause clang to emit the following warning "'break' is bound to loop, GCC
binds it to switch", which is a false positive, and both gcc and clang bind
the break to the inner switch. In order to workaround this issue, disable the
gcc-compat checks for the usage of the read_atomic macro.
This has been reported upstream as http://bugs.llvm.org/show_bug.cgi?id=32595.
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Release-acked-by: Julien Grall <julien.grall@arm.com>
User can set max freq to specific cpu by
"xenpm set-scaling-maxfreq [cpuid] <HZ>"
or set max freq to all cpu with default cpuid by
"xenpm set-scaling-maxfreq <HZ>".
Set max freq with default cpuid will cause
segmentation fault after commit id d4906b5d05.
This patch will fix this issue and add ability
to set max freq with default cpuid.
Signed-off-by: Luwei Kang <luwei.kang@intel.com>
Compile-tested-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Release-acked-by: Julien Grall <julien.grall@arm.com>
Since the counter is unsigned, it's pointless/bogous to check
for if to be above zero.
Check that it is at least one before it's decremented, instead.
Spotted by Coverity.
Reported-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
Reviewed-by: George Dunlap <george.dunlap@citrix.com>
Release-acked-by: Julien Grall <julien.grall@arm.com>
The patch actually doesn't impact the functionality as such. This only replaces
bool_t with bool in credit2.
Signed-off-by: Praveen Kumar <kpraveen.lkml@gmail.com>
Reviewed-by: George Dunlap <george.dunlap@citrix.com>
Release-acked-by: Julien Grall <julien.grall@arm.com>
Contrary to what I wrote in d0db50ced1 "Config.mk: Update for
4.9.0-rc1.1", the build failure with 4.9.0-rc1 was not due to a wrong
qemu tag, but a wrong mini-os tag. So burn 4.9.0-rc1.1 too :-(. (We
can rewind the qemu-trad tag to 4.9.0-rc1; the -rc1 and -rc1.1 tags
are identical.)
Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
In qemu-trad, I made xen-4.9.0-rc1 refer erroneously to the 4.8
branch. That doesn't build. So we are burning the version number
4.9.0-rc1 in xen.git and qemu-trad. (The other trees can remain as
they are.)
Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
* Update Config.mk REVISION values to refer to relevant tags.
* Update README version number
* Update xen/Makefile version number
Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
The changes introduced on c47d1d broke the clang build due to undefined
references to __xsm_action_mismatch_detected, because clang hasn't optimized
the code properly. The following patch allows the clang build to work again,
while keeping the same functionality.
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Only attempt to restore from saved state if it exists.
Without this, oxenstored immediately exits with an exception if the
--restart option is provided but the state file is not present.
(The time-of-check to time-of-use race isn't a concern as oxenstored is
the only thing that should write the state file.)
Signed-off-by: Jonathan Davies <jonathan.davies@citrix.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Christian Lindig <christian.lindig@citrix.com>
Release-acked-by: Julien Grall <julien.grall@arm.com>
Previously, Domain.dump output the number of the local port
corresponding to each domain's event-channel. However, when oxenstored
exits, it closes /dev/xen/evtchn which causes the kernel to close the
local port (evtchn_release), so this port is no longer useful.
Instead, store the remote port. This can be used to reconnect the
event-channel by binding the original remote port to a fresh local port.
Indeed, the logic for parsing the stored state already expects a remote
port as it passes the parsed port number to Domain.make (via
Domains.create), which takes a remote port.
Signed-off-by: Jonathan Davies <jonathan.davies@citrix.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Christian Lindig <christian.lindig@citrix.com>
Release-acked-by: Julien Grall <julien.grall@arm.com>
Internally, paths are represented as lists of strings, where
* path "/" is represented by []
* path "/local/domain/0" is represented by ["local"; "domain"; "0"]
(see comment for Store.Path.t).
However, the traversal function generated paths like
[""; "local"; "domain"; "0"]
because the name of the root node is "". Change it to generate paths
correctly.
Furthermore, the function passed to Store.dump_fct would render the node
"foo" under the path [] as "//foo". Change this to return "/foo".
Signed-off-by: Jonathan Davies <jonathan.davies@citrix.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Christian Lindig <christian.lindig@citrix.com>
Release-acked-by: Julien Grall <julien.grall@arm.com>
This reverts commit b32d442abd. There is
no need for this patch after "xen/arm: Set and restore HCR_EL2 register
for each vCPU separately".
Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Julien Grall <julien.grall@arm.com>
The ITS uses device IDs to map LPIs to a device. Dom0 will later use
those IDs, which we directly pass on to the host.
For this we have to map each device that Dom0 may request to a host
ITS device with the same identifier.
Allocate the respective memory and enter each device into an rbtree to
later be able to iterate over it or to easily teardown guests.
Because device IDs are per ITS, we need to identify a virtual ITS. We
use the doorbell address for that purpose, as it is a nice architectural
MSI property and spares us handling with opaque pointer or break
the VGIC abstraction.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Julien Grall <julien.grall@arm.com>
Create a new file to hold the emulation code for the ITS widget.
This just holds the data structure and a init and free function for now.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Julien Grall <julien.grall@arm.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
The number of LPIs on a host can be potentially huge (millions),
although in practise will be mostly reasonable. So prematurely allocating
an array of struct irq_desc's for each LPI is not an option.
However Xen itself does not care about LPIs, as every LPI will be injected
into a guest (Dom0 for now).
Create a dense data structure (8 Bytes) for each LPI which holds just
enough information to determine the virtual IRQ number and the VCPU into
which the LPI needs to be injected.
Also to not artificially limit the number of LPIs, we create a 2-level
table for holding those structures.
This patch introduces functions to initialize these tables and to
create, lookup and destroy entries for a given LPI.
By using the naturally atomic access guarantee the native uint64_t data
type gives us, we allocate and access LPI information in a way that does
not require a lock.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Julien Grall <julien.grall@arm.com>
To be able to easily send commands to the ITS, create the respective
wrapper functions, which take care of the ring buffer.
The first two commands we implement provide methods to map a collection
to a redistributor (aka host core) and to flush the command queue (SYNC).
Start using these commands for mapping one collection to each host CPU.
As an ITS might choose between *two* ways of addressing a redistributor,
we store both the MMIO base address as well as the processor number in
a per-CPU variable to give each ITS what it wants.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Instead of directly manipulating the tables in memory, an ITS driver
sends commands via a ring buffer in normal system memory to the ITS h/w
to create or alter the LPI mappings.
Allocate memory for that buffer and tell the ITS about it to be able
to send ITS commands.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Julien Grall <julien.grall@arm.com>
Each ITS maps a pair of a DeviceID (for instance derived from a PCI
b/d/f triplet) and an EventID (the MSI payload or interrupt ID) to a
pair of LPI number and collection ID, which points to the target CPU.
This mapping is stored in the device and collection tables, which software
has to provide for the ITS to use.
Allocate the required memory and hand it over to the ITS.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Julien Grall <julien.grall@arm.com>
The ARM GICv3 provides a new kind of interrupt called LPIs.
The pending bits and the configuration data (priority, enable bits) for
those LPIs are stored in tables in normal memory, which software has to
provide to the hardware.
Allocate the required memory, initialize it and hand it over to each
redistributor. The maximum number of LPIs to be used can be adjusted with
the command line option "max_lpi_bits", which defaults to 20 bits,
covering about one million LPIs.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Julien Grall <julien.grall@arm.com>
Map the registers frame for each host ITS and populate the host ITS
structure with some parameters describing the size of certain properties
like the number of bits for device IDs.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Parse the GIC subnodes in the device tree to find every ITS MSI controller
the hardware offers. Store that information in a list to both propagate
all of them later to Dom0, but also to be able to iterate over all ITSes.
This introduces an ITS Kconfig option (as an EXPERT option), use
XEN_CONFIG_EXPERT=y on the make command line to see and use the option.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Julien Grall <julien.grall@arm.com>
Right now, we use cpumask_first() for going through
the bus pCPUs in csched_load_balance(). This means
not all pCPUs have equal chances of seeing their
pending work stolen. It also means there is more
runqueue lock pressure on lower ID pCPUs.
To avoid all this, let's record and remember, for
each NUMA node, from what pCPU we have stolen for
last, and start from that the following time.
Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
Acked-by: George Dunlap <george.dunlap@citrix.com>
During load balancing, we check the non idle pCPUs to
see if they have runnable but not running vCPUs that
can be stolen by and set to run on currently idle pCPUs.
If a pCPU has only one running (or runnable) vCPU,
though, we don't want to steal it from there, and
it's therefore pointless bothering with it
(especially considering that bothering means trying
to take its runqueue lock!).
On large systems, when load is only slightly higher
than the number of pCPUs (i.e., there are just a few
more active vCPUs than the number of the pCPUs), this
may mean that:
- we go through all the pCPUs,
- for each one, we (try to) take its runqueue locks,
- we figure out there's actually nothing to be stolen!
To mitigate this, we introduce a counter for the number
of runnable vCPUs on each pCPU. In fact, unless there
re least 2 runnable vCPUs --typically, one running,
and the others in the runqueue-- it does not make sense
to try stealing anything.
Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
Reviewed-by: George Dunlap <george.dunlap@citrix.com>
cpumask_any() is costly (because of the randomization).
And since it does not really matter which exact CPU is
selected within a runqueue, as that will be overridden
shortly after, in runq_tickle(), spending too much time
and achieving true randomization is pretty pointless.
As the picked CPU, however, would be used as an hint,
within runq_tickle(), don't give up on it entirely,
and let's make sure we don't always return the same
CPU, or favour lower or higher ID CPUs.
To achieve that, let's record and remember, for each
runqueue, what CPU we picked for last, and start from
that the following time.
Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
Acked-by: George Dunlap <george.dunlap@citrix.com>
Including whether we actually tried stealing a vCPU from
a given pCPU, or we skipped that one, because of lock
contention.
Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
Acked-by: George Dunlap <george.dunlap@citrix.com>
Currently, it can happen that __runq_tickle(),
running on pCPU 2 because vCPU x woke up, decides
to tickle pCPU 3, because it's idle. Just after
that, but before pCPU 3 manages to schedule and
pick up x, either __runq_tickel() or
__csched_cpu_pick(), running on pCPU 6, sees that
idle pCPUs are 0, 1 and also 3, and for whatever
reason it also chooses 3 for waking up (or
migrating) vCPU y.
When pCPU 3 goes through the scheduler, it will
pick up, say, vCPU x, and y will sit in its
runqueue, even if there are idle pCPUs.
Alleviate this by marking a pCPU to be idle
right away when tickling it (like, e.g., it happens
in Credit2).
Note that this does not eliminate the race. That
is not possible without introducing proper locking
for the cpumasks the scheduler uses. It significantly
reduces the window during which it can happen, though.
Introduce proper locking for the cpumask can, in
theory, be done, and may be investigated in future.
It is a significant amount of work to do it properly
(e.g., avoiding deadlock), and it is likely to adversely
affect scalability, and so it may be a path it is just
not worth following.
Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
Reviewed-by: George Dunlap <george.dunlap@citrix.com>
Checking whether or not a vCPU can be 'stolen'
from a peer pCPU's runqueue is relatively cheap.
Therefore, let's do that as early as possible,
avoiding potentially useless complex checks, and
cpumask manipulations.
Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
Reviewed-by: George Dunlap <george.dunlap@citrix.com>
Since we're holding the lock on the pCPU from which we
are trying to steal, it can't have disappeared, so we
can drop the check for that (and convert it in an
ASSERT()).
And since we try to steal only from busy pCPUs, it's
unlikely for such pCPU to be idle, so we can:
- tell the compiler this is actually unlikely,
- bail early if the pCPU, unfortunately, turns out
to really be idle.
Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
Reviewed-by: George Dunlap <george.dunlap@eu.citrix.com>
SVM's maximum valid event type is 4. This appears to be a straigth copy and
paste error in c/s e94e3f210a, as VT-x's maximum is 6.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
...rather than leaving fragments of old instructions in place. This reduces
the chances of something going further-wrong (as the debug trap will be caught
and terminate the guest) in a cascade-failure where we end up executing the
instruction fragments.
Before:
(XEN) d2v0 exception 6 (ec=0000) in emulation stub (line 6239)
(XEN) d2v0 stub: c4 e1 44 77 c3 80 d0 82 ff ff ff d1 90 ec 90
After:
(XEN) d3v0 exception 6 (ec=0000) in emulation stub (line 6239)
(XEN) d3v0 stub: c4 e1 44 77 c3 cc cc cc cc cc cc cc cc cc cc
To make this work, the int3 handler needs to be extended to attempt recovery
rather than simply returning back to Xen context. While altering do_int3(),
leave an obvious sign if an embedded breakpoint has been hit and not dealt
with by debugging facilities.
(XEN) Hit embedded breakpoint at ffff82d0803d01f6 [extable.c#stub_selftest+0xda/0xee]
Extend the selftests to include int3, and add an extra printk indicating the
start of the recovery selftests, to avoid leaving otherwise-spurious faults
visible in the log.
(XEN) build-id: 55d7e6f420b4f0ce277f776be620f43d7cb8646c
(XEN) Running stub recovery selftests...
(XEN) traps.c:3466: GPF (0000): ffff82d0bffff041 [ffff82d0bffff041] -> ffff82d08035937a
(XEN) traps.c:813: Trap 12: ffff82d0bffff040 [ffff82d0bffff040] -> ffff82d08035937a
(XEN) traps.c:1215: Trap 3: ffff82d0bffff041 [ffff82d0bffff041] -> ffff82d08035937a
(XEN) ACPI sleep modes: S3
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
After an ioreq server has unmapped, the remaining p2m_ioreq_server
entries need to be reset back to p2m_ram_rw. This patch does this
synchronously by iterating the p2m table.
The synchronous resetting is necessary because we need to guarantee
the p2m table is clean before another ioreq server is mapped. And
since the sweeping of p2m table could be time consuming, it is done
with hypercall continuation.
Signed-off-by: Yu Zhang <yu.c.zhang@linux.intel.com>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: George Dunlap <george.dunlap@citrix.com>
After an ioreq server has unmapped, the remaining p2m_ioreq_server
entries need to be reset back to p2m_ram_rw. This patch does this
asynchronously with the current p2m_change_entry_type_global()
interface.
New field entry_count is introduced in struct p2m_domain, to record
the number of p2m_ioreq_server p2m page table entries. One nature of
these entries is that they only point to 4K sized page frames, because
all p2m_ioreq_server entries are originated from p2m_ram_rw ones in
p2m_change_type_one(). We do not need to worry about the counting for
2M/1G sized pages.
This patch disallows mapping of an ioreq server, when there's still
p2m_ioreq_server entry left, in case another mapping occurs right after
the current one being unmapped, releases its lock, with p2m table not
synced yet.
This patch also disallows live migration, when there's remaining
p2m_ioreq_server entry in p2m table. The core reason is our current
implementation of p2m_change_entry_type_global() lacks information
to resync p2m_ioreq_server entries correctly if global_logdirty is
on.
We still need to handle other recalculations, however; which means
that when doing a recalculation, if the current type is
p2m_ioreq_server, we check to see if p2m->ioreq.server is valid or
not. If it is, we leave it as type p2m_ioreq_server; if not, we reset
it to p2m_ram as appropriate.
To avoid code duplication, lift recalc_type() out of p2m-pt.c and use
it for all type recalculations (both in p2m-pt.c and p2m-ept.c).
Signed-off-by: Yu Zhang <yu.c.zhang@linux.intel.com>
Signed-off-by: George Dunlap <george.dunlap@citrix.com>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
In ept_handle_violation(), write violations are also treated as
read violations. And when a VM is accessing a write-protected
address with read-modify-write instructions, the read emulation
process is triggered first.
For p2m_ioreq_server pages, current ioreq server only forwards
the write operations to the device model. Therefore when such page
is being accessed by a read-modify-write instruction, the read
operations should be emulated here in hypervisor. This patch provides
such a handler to copy the data to the buffer.
Note: MMIOs with p2m_mmio_dm type do not need such special treatment
because both reads and writes will go to the device mode.
Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Signed-off-by: Yu Zhang <yu.c.zhang@linux.intel.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
A new device model wrapper is added for the newly introduced
DMOP - XEN_DMOP_map_mem_type_to_ioreq_server.
Since currently this DMOP only supports the emulation of write
operations, attempts to trigger the DMOP with values other than
XEN_DMOP_IOREQ_MEM_ACCESS_WRITE or 0(to unmap the ioreq server)
shall fail. The wrapper shall be updated once read operations
are also to be emulated in the future.
Also note currently this DMOP only supports one memory type,
and can be extended in the future to map multiple memory types
to multiple ioreq servers, e.g. mapping HVMMEM_ioreq_serverX to
ioreq server X, This wrapper shall be updated when such change
is made.
Signed-off-by: Yu Zhang <yu.c.zhang@linux.intel.com>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Jan Beulich
Wei Liu
Alistair Francis
Andrew Cooper
Chao Gao
Roger Pau Monné
Luwei Kang
Dario Faggioli
Praveen Kumar
Ian Jackson
Jonathan Davies
Stefano Stabellini
Andre Przywara
Yu Zhang
Paul Durrant