x86/HVM: fix failure path in hvm_vcpu_initialise

It looks like one of the failure cases in hvm_vcpu_initialise jumps to
the wrong label; this could lead to slow leaks if something isn't
cleaned up properly.

I will probably change these labels in a future patch, but I figured
it was better to have this fix separately.

This is also a candidate for backport.

Signed-off-by: George Dunlap <george.dunlap@eu.citrix.com>
Signed-off-by: Mukesh Rathor <mukesh.rathor@oracle.com>
VMX: fix failure path in construct_vmcs

If the allocation fails, make sure to call vmx_vmcs_exit().

This is a candidate for backport.

Signed-off-by: George Dunlap <george.dunlap@eu.citrix.com>
Signed-off-by: Mukesh Rathor <mukesh.rathor@oracle.com>
x86: mark BUG()s and assertion failures as terminal.

This helps avoid static analysis false-positives, and might lead to
better code density as the compiler knows it doesn't have to restore
spilled state &c.

Signed-off-by: Tim Deegan <tim@xen.org>
Acked-by: Keir Fraser <keir@xen.org>
tools: print xm deprecation warning to stderr

To avoid confusing anything which is parsing the output.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
x86/HVM: properly handle MMIO reads and writes wider than a machine word

Just like real hardware we ought to split such accesses transparently
to the caller. With little extra effort we can at once even handle page
crossing accesses correctly.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Keir Fraser <keir@xen.org>
x86: fix dependencies of emulator test

Rather than mentioning the (linked) directory, mention the files thus
making sure things get rebuild as needed when the core emulator files
change.

Also enable debug info generation unconditionally, as this is testing
stuff only anyway.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Keir Fraser <keir@xen.org>
x86_emulate: MOVSXD must read source operand just once

... for the case of accessing MMIO.

Also streamline the ARPL emulation a little, and add tests for both
instructions (the MOVSXD one requires a few other adjustments, as we
now need to run in a mode where the emulator's mode_64bit() returns
true).

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Keir Fraser <keir@xen.org>
x86_emulate: PUSH <mem> must read source operand just once

... for the case of accessing MMIO.

Rather than doing the early operand type adjustment for just for that
case, do it for all of the 0xF6, 0xF7, and 0xFF groups (allowing some
other code to be dropped instead).

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Keir Fraser <keir@xen.org>
x86_emulate: fix flag setting for 8-bit signed multiplication

We really need to check for a signed overflow of 8 bits, while the
previous check compared the sign-extended 8-bit result with the
zero-extended 16-bit one (which was wrong for all negative results).

Once at it
- also adjust the 16-bit comparison for symmetry
- improve the 8-bit multiplication (no need to zero-extend to 32-bits
  the sign-extended to 16 bits original 8-bit value)
- fold both signed multiplication variants

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Keir Fraser <keir@xen.org>
x86_emulate: fold wide reads

With HVM's MMIO operand handling now being capable of splitting large
reads, there's no need to issue at most machine word size reads when
we really need wider operands.

Not that this is not done everywhere - there are a couple of cases
where keeping the reads separate is more natural (and folding them
would complicate the code rather than simplifying it).

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Keir Fraser <keir@xen.org>
sched_credit: filter node-affinity mask against online cpus

in _csched_cpu_pick(), as not doing so may result in the domain's
node-affinity mask (as retrieved by csched_balance_cpumask() )
and online mask (as retrieved by cpupool_scheduler_cpumask() )
having an empty intersection.

Therefore, when attempting a node-affinity load balancing step
and running this:

    ...
    /* Pick an online CPU from the proper affinity mask */
    csched_balance_cpumask(vc, balance_step, &cpus);
    cpumask_and(&cpus, &cpus, online);
    ...

we end up with an empty cpumask (in cpus). At this point, in
the following code:

    ....
    /* If present, prefer vc's current processor */
    cpu = cpumask_test_cpu(vc->processor, &cpus)
            ? vc->processor
            : cpumask_cycle(vc->processor, &cpus);
    ....

an ASSERT (from inside cpumask_cycle() ) triggers like this:

(XEN) Xen call trace:
(XEN)    [<ffff82d08011b124>] _csched_cpu_pick+0x1d2/0x652
(XEN)    [<ffff82d08011b5b2>] csched_cpu_pick+0xe/0x10
(XEN)    [<ffff82d0801232de>] vcpu_migrate+0x167/0x31e
(XEN)    [<ffff82d0801238cc>] cpu_disable_scheduler+0x1c8/0x287
(XEN)    [<ffff82d080101b3f>] cpupool_unassign_cpu_helper+0x20/0xb4
(XEN)    [<ffff82d08010544f>] continue_hypercall_tasklet_handler+0x4a/0xb1
(XEN)    [<ffff82d080127793>] do_tasklet_work+0x78/0xab
(XEN)    [<ffff82d080127a70>] do_tasklet+0x5f/0x8b
(XEN)    [<ffff82d080158985>] idle_loop+0x57/0x5e
(XEN)
(XEN)
(XEN) ****************************************
(XEN) Panic on CPU 1:
(XEN) Assertion 'cpu < nr_cpu_ids' failed at /home/dario/Sources/xen/xen/xen.git/xen/include/xe:16481

It is for example sufficient to have a domain with node-affinity
to NUMA node 1 running, and issueing a `xl cpupool-numa-split'
would make the above happen. That is because, by default, all
the existing domains remain assigned to the first cpupool, and
it now (after the cpupool-numa-split) only includes NUMA node 0.

This change prevents that by generalizing the function used
for figuring out whether a node-affinity load balancing step
is legit or not. This way we can, in _csched_cpu_pick(),
figure out early enough that the mask would end up empty,
skip the step all together and avoid the splat.

Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
Reviewed-by: George Dunlap <george.dunlap@eu.citrix.com>
gnttab: remove unused shared header lookup

Coverity-ID: 1056171

Signed-off-by: Matthew Daley <mattjd@gmail.com>
Reviewed-by: Tim Deegan <tim@xen.org>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
unmodified_drivers: enable unplug per default

Since xen-3.3 an official unplug protocol for emulated hardware is
available in the toolstack. The pvops kernel does the unplug per
default, so it is safe to do it also in the drivers for forward ported
xenlinux.
Currently its required to load xen-platform-pci with the module
parameter dev_unplug=all, which is cumbersome.
Also recognize the dev_unplug=never parameter, which provides the
default before this patch.

Signed-off-by: Olaf Hering <olaf@aepfle.de>