Commit Graph
38236 Commits
Author SHA1 Message Date
Marek Marczykowski-Górecki ffb60a58df tools/misc/xenpm: fix getting info when some CPUs are offline
Use physinfo.max_cpu_id instead of physinfo.nr_cpus to get max CPU id.
This fixes for example 'xenpm get-cpufreq-para' with smt=off, which
otherwise would miss half of the cores.

Signed-off-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
2018-11-01 10:20:34 +00:00
Marek Marczykowski-Górecki 5e28d84035 tools/hotplug: remove xen-hotplug-cleanup
Since udev is no longer used to call hotplug scripts (neither in dom0
nor driver domain), this scripts is no longer referenced anywhere. libxl
(xl devd or else) has own cleanup code.

Signed-off-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
2018-11-01 10:19:12 +00:00
Andrew Cooper 96f235c26f x86: Consolidate the storage of MSR_AMD64_DR{0-3}_ADDRESS_MASK
The PV and HVM code both have a copy of these, which gives the false
impression in the context switch code that they are PV/HVM specific.

Move the storage into struct vcpu_msrs, and update all users to match.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2018-11-01 10:15:10 +00:00
Paul Durrant d5d30b3949 viridian: move the code into its own sub-directory
Subsequent patches will introduce support for more viridian enlightenments
which will make a single source module quite lengthy.

This patch therefore creates a new arch/x86/hvm/viridian sub-directory and
moves viridian.c into that.

The patch also fixes some bad whitespace whilst moving the code and
adjusts the MAINTAINERS file.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
2018-10-31 17:59:53 +01:00
Roger Pau Monné ce47462cb4 x86/pvh: allow PVH Dom0 to use the debug IO port console
Force trapping accesses to IO port 0xe9 for a PVH Dom0, so it can
print to the HVM debug console.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
2018-10-31 17:59:26 +01:00
Roger Pau Monné d3611dd500 x86/hvm: introduce a define for the debug output IO port
No functional change intended.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
2018-10-31 17:58:47 +01:00
Roger Pau Monné ac25bf3b23 x86/pvh: fix TSC mode setup for PVH Dom0
A PVH Dom0 might use TSC scaling or other HVM specific TSC
adjustments, so only short-circuit the TSC setup for a classic PV
Dom0.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
2018-10-31 17:58:15 +01:00
Jan Beulich ee91031be2 use consistent values when consuming runtime-changeable parameters
There's no guarantee that e.g. a switch() control expression's memory
operand(s) get(s) read just once. Guard against the compiler producing
"unexpected" code by sprinkling around some ACCESS_ONCE().

I'm leaving alone opt_conswitch[]: It gets accessed in quite a few
places anyway, and an intermediate change won't have any severe effect
afaict.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: George Dunlap <george.dunlap@citrix.com>
2018-10-31 17:57:19 +01:00
Stefano Stabellini 8e751ac59c xen/arm: introduce NO_PLAT
Add a Kconfig option to select no specific platform support.

Signed-off-by: Stefano Stabellini <stefanos@xilinx.com>
Reviewed-by: Andrii Anisov <andrii_anisov@epam.com>
2018-10-30 10:58:30 -07:00
Stefano Stabellini 4829b80eee xen/arm: make platform specific code dependent on ALL32_PLAT or ALL64_PLAT
Compile platform code that doesn't have its own specific kconfig option
only if ALL32_PLAT or ALL64_PLAT depending on the architecture. The
benefit is that choosing one of the platforms available as a menu
option allows the user not to build other unnecessary platform code.

Signed-off-by: Stefano Stabellini <stefanos@xilinx.com>
Reviewed-by: Andrii Anisov <andrii_anisov@epam.com>
2018-10-30 10:58:29 -07:00
Ian Jackson f355ed8448 libxencall: Improve linux syscall error messages
Make the bufdev and non-bufdev messages distinct, and always print the
non-constant argument (ie, the size).

This assists diagnosis.

CC: Andrew Cooper <andrew.cooper3@citrix.com>
CC: Hans van Kranenburg <hans@knorrie.org>
Acked-by: Wei Liu <wei.liu2@citrix.com>
2018-10-30 17:03:31 +00:00
Ian Jackson 65c0bcc471 libxl: libxl__ev_fd_callback: Document perhaps-no-retry semantics
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
CC: Anthony PERARD <anthony.perard@citrix.com>
2018-10-30 17:03:27 +00:00
Ian Jackson a23744e9ee libxl: CODING_STYLE: Clarify line length limit to 75
And give a reason.

The previous `limit' of 75-80 was ambiguous.

Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
CC: Anthony PERARD <anthony.perard@citrix.com>
2018-10-30 17:03:23 +00:00
Andrew Cooper f993c3e907 x86/pv: Fix crash when using xl set-parameter pcid=...
"pcid=" is registered as a runtime parameter, which means that parse_pcid()
must not reside in .init, or the following happens when parse_params() tries
to call an unmapped function pointer.

  (XEN) ----[ Xen-4.12-unstable  x86_64  debug=y   Not tainted ]----
  (XEN) CPU:    0
  (XEN) RIP:    e008:[<ffff82d080407fb3>] ffff82d080407fb3
  (XEN) RFLAGS: 0000000000010292   CONTEXT: hypervisor (d0v1)
  (XEN) rax: ffff82d080407fb3   rbx: ffff82d0803cf270   rcx: 0000000000000000
  (XEN) rdx: ffff8300abe67fff   rsi: 000000000000000a   rdi: ffff8300abe67bfd
  (XEN) rbp: ffff8300abe67ca8   rsp: ffff8300abe67ba0   r8:  ffff83084d980000
  (XEN) r9:  0000000000000000   r10: 0000000000000000   r11: 0000000000000000
  (XEN) r12: ffff8300abe67bfd   r13: ffff82d0803cb628   r14: 0000000000000000
  (XEN) r15: ffff8300abe67bf8   cr0: 0000000080050033   cr4: 0000000000172660
  (XEN) cr3: 0000000828efd000   cr2: ffff82d080407fb3
  (XEN) fsb: 00007fb810d4b780   gsb: ffff88007ce20000   gss: 0000000000000000
  (XEN) ds: 0000   es: 0000   fs: 0000   gs: 0000   ss: e010   cs: e008
  (XEN) Xen code around <ffff82d080407fb3> (ffff82d080407fb3) [fault on access]:
  (XEN)  -- -- -- -- -- -- -- -- <--> -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
  (XEN) Xen stack trace from rsp=ffff8300abe67ba0:
  (XEN)    ffff82d080217f61 ffff830826db0f09 ffff8300abe67bf8 ffff82d0803cf1e0
  (XEN)    00007cff54198409 ffff8300abe67bf0 010001d000000000 0000000000000000
  (XEN)    ffff82d0803cf288 ffff8300abe67c88 ffff82d0805a09c0 616c620064696370
  (XEN)    00000000aaaa0068 0000000000000296 ffff82d08023d60e aaaaaaaaaaaaaaaa
  (XEN)    ffff83084d9b4000 ffff8300abe67c68 ffff82d08024940e ffff83083736e000
  (XEN)    0000000000000080 000000000000007a 000000000000000a ffff82d08045e61c
  (XEN)    ffff82d080573d80 ffff8300abe67cb8 ffff82d080249805 80000007fce54067
  (XEN)    fffffffffffffff2 ffff830826db0f00 ffff8300abfa7000 ffff82d08045e61c
  (XEN)    ffff82d080573d80 ffff8300abe67cb8 ffff82d08021801e ffff8300abe67e48
  (XEN)    ffff82d08023f60a ffff83083736e000 0000000000000000 ffff8300abe67d58
  (XEN)    ffff82d080293d90 0000000000000092 ffff82d08023d60e ffff820040006ae0
  (XEN)    0000000000000000 0000000000000000 00007fb810d5c010 ffff83083736e248
  (XEN)    0000000000000286 ffff8300abe67d58 0000000000000000 ffff82e010521b00
  (XEN)    0000000000000206 0000000000000000 0000000000000000 ffff8300abe67e48
  (XEN)    ffff82d080295270 00000000ffffffff ffff83083736e000 ffff8300abe67e48
  (XEN)    ffff820040006ae0 ffff8300abe67d98 000000120000001c 00007fb810d5d010
  (XEN)    0000000000000009 0000000000000002 0000000000000001 00007fb810b53260
  (XEN)    0000000000000001 0000000000000000 0000000000638bc0 00007fb81066a748
  (XEN)    00007ffe11087881 0000000000000002 0000000000000001 00007fb810b53260
  (XEN)    0000000000638b60 0000000000000000 00007fb8100322a0 ffff82d08035d444
  (XEN) Xen call trace:
  (XEN)    [<ffff82d080217f61>] kernel.c#parse_params+0x34a/0x3eb
  (XEN)    [<ffff82d08021801e>] runtime_parse+0x1c/0x1e
  (XEN)    [<ffff82d08023f60a>] do_sysctl+0x108d/0x1241
  (XEN)    [<ffff82d0803535cb>] pv_hypercall+0x1ac/0x4c5
  (XEN)    [<ffff82d08035d4a2>] lstar_enter+0x112/0x120
  (XEN)
  (XEN) Pagetable walk from ffff82d080407fb3:
  (XEN)  L4[0x105] = 00000000abe5c063 ffffffffffffffff
  (XEN)  L3[0x142] = 00000000abe59063 ffffffffffffffff
  (XEN)  L2[0x002] = 000000084d9bf063 ffffffffffffffff
  (XEN)  L1[0x007] = 0000000000000000 ffffffffffffffff
  (XEN)
  (XEN) ****************************************
  (XEN) Panic on CPU 0:
  (XEN) FATAL PAGE FAULT
  (XEN) [error_code=0010]
  (XEN) Faulting linear address: ffff82d080407fb3
  (XEN) ****************************************

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2018-10-30 13:26:21 +00:00
Andrew Cooper c238ea3f4c x86/vvmx: Don't handle unknown nested vmexit reasons at L0
This is very dangerous from a security point of view, because a missing entry
will cause L2's action to be interpreted as L1's action.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Sergey Dyasli <sergey.dyasli@citrix.com>
Acked-by: Kevin Tian <kevin.tian@intel.com>
2018-10-30 13:26:21 +00:00
Andrew Cooper 307ee30a14 x86/vvmx: Drop the now-obsolete vmx_inst_check_privilege()
Now that nvmx_handle_vmx_insn() performs all VT-x instruction checks, there is
no need for redundant checking in vmx_inst_check_privilege().  Remove it, and
take out the vmxon_check boolean which was plumbed through decode_vmx_inst().

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Sergey Dyasli <sergey.dyasli@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Kevin Tian <kevin.tian@intel.com>
2018-10-30 13:26:21 +00:00
Andrew Cooper 18cef4df8f x86/vvmx: Unconditionally initialise vmxon_region_pa during vcpu construction
This is a stopgap solution until the toolstack side of initialisation can be
sorted out, but it does result in the nvmx_vcpu_in_vmx() predicate working
correctly even when nested virt hasn't been enabled for the domain.

Update nvmx_handle_vmx_insn() to include the in-vmx mode check (for all
instructions other than VMXON) to complete the set of #UD checks.

In addition, sanity check that the nested vmexit handler has worked correctly,
and that we are only providing emulation of the VT-x instructions to L1
guests.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Sergey Dyasli <sergey.dyasli@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Kevin Tian <kevin.tian@intel.com>
2018-10-30 13:26:21 +00:00
Andrew Cooper 6faff8f900 x86/vvmx: Let L1 handle all the unconditional vmexit instructions
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Sergey Dyasli <sergey.dyasli@citrix.com>
Acked-by: Kevin Tian <kevin.tian@intel.com>
2018-10-30 13:26:21 +00:00
Andrew Cooper 30f43f4aa8 x86: Reorganise and rename debug register fields in struct vcpu
Reusing debugreg[5] for the PV emulated IO breakpoint information is confusing
to read.  Instead, introduce a dr7_emul field in pv_vcpu for the purpose.

With the PV emulation out of the way, debugreg[4,5] are entirely unused and
don't need to be stored.

Rename debugreg[0..3] to dr[0..3] to reduce code volume, but keep them as an
array because their behaviour is identical and this helps simplfy some of the
PV handling.  Introduce dr6 and dr7 fields to replace debugreg[6,7] which
removes the storage for debugreg[4,5].

In arch_get_info_guest(), handle the merging of emulated dr7 state alongside
all other dr handling, rather than much later.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2018-10-30 13:26:21 +00:00
Andrew Cooper 2b3218eb6b x86/emul: Unfold %cr4.de handling in x86emul_read_dr()
No functional change (as curr->arch.debugreg[5] is zero when DE is clear), but
this change simplifies the following patch.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
2018-10-30 13:26:21 +00:00
Andrew Cooper 0a1fa63502 x86/domain: Fix build with GCC 4.3.x
GCC 4.3.x can't initialise the user_regs structure like this.

Reported-by: Jan Beulich <JBeulich@suse.com>
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
2018-10-30 13:26:21 +00:00
Stefano Stabellini ce75973a27 arm,smmu: backport "Disable stalling faults for all endpoints"
Backport commit 3714ce1d6655098ee69ede632883e5874d67e4ab
"iommu/arm-smmu: Disable stalling faults for all endpoints" from the
Linux kernel. This works-around Erratum #842869.

Original commit message:

  Enabling stalling faults can result in hardware deadlock on poorly
  designed systems, particularly those with a PCI root complex upstream of
  the SMMU.

  Although it's not really Linux's job to save hardware integrators from
  their own misfortune, it *is* our job to stop userspace (e.g. VFIO
  clients) from hosing the system for everybody else, even if they might
  already be required to have elevated privileges.

  Given that the fault handling code currently executes entirely in IRQ
  context, there is nothing that can sensibly be done to recover from
  things like page faults anyway, so let's rip this code out for now and
  avoid the potential for deadlock.

  Cc: <stable@vger.kernel.org>
  Fixes: 48ec83bcbcf5 ("iommu/arm-smmu: Add initial driver support for ARM SMMUv3 devices")
  Reported-by: Matt Evans <matt.evans@arm.com>
  Signed-off-by: Will Deacon <will.deacon@arm.com>

Signed-off-by: Stefano Stabellini <stefanos@xilinx.com>
Acked-by: Julien Grall <julien.grall@arm.com>
2018-10-29 14:24:28 -07:00
George Dunlap dafd936ddd Make credit2 the default scheduler
Credit2 was declared "supported" in 4.8, and as of 4.10 had two other
critical features implemented (soft affinity / NUMA and caps).

Why change the default?

The code is better: more predictable, less jitter, easier to determine
how modifications will affect overall behavior, easier in the future
to make load-balancing behavior more subtle (e.g., taking into account
the cost of powering up extra cores, &c).

Overall performance compared to Credit1 is somewhat of a mixed bag.
Unfortunately most of what I have are tests using XenServer's internal
perf testing system, so I can't share the raw data (via links anyway).

Here is a summary of data from an internal e-mail Dario sent in the
past:

* DVDbench: On underloaded systems, credit2 outperformed credit1 by
about 4%.  On overloaded systems, credit2 underperformed by about 3%.

* On a range of tests (unixbench, lmbench, &c), credit and credit2
perform within 5% of each other (up and down).

* Credit2 fairly consistently beats credit for TCP-style workloads.

* Credit2 is sometimes equal to, sometimes 5-15% worse than, credit for
synthetic CPU workloads (e.g., Dhrystone).

* On LoginVSI, credit2 fairly consistently outperforms credit by about 10%.

Credit2, like credit, has a number of workloads / setups for which
performance could be improved.  Personally I think networking and
partially-loaded systems is going to be more representative of what
Xen is actually used for; so I think credit2 is on the whole the
better scheduler to use by default.  And in any case, making those
improvements on credit2 will be easier than on credit.

Signed-off-by: George Dunlap <george.dunlap@citrix.com>
Acked-by: Dario Faggioli <dfaggioli@suse.com>
2018-10-29 14:58:34 +00:00
Paul Durrant 1ecb1ee4d8 amd-iommu: get rid of pointless IOMMU_PAGING_MODE_LEVEL_X definitions
The levels are absolute numbers such that IOMMU_PAGING_MODE_LEVEL_X
evaluates to X (for the valid range of 0 - 7) so simply use numbers in
the code.

No functional change.

NOTE: This patch also adds emacs boilerplate to amd-iommu-defs.h

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Acked-by: Brian Woods <brian.woods@amd.com>
2018-10-29 13:47:24 +01:00
Jan Beulich 9254b0f5e9 x86emul: generalize vector length handling for AVX512/EVEX
To allow for some code sharing where possible, copy VEX.L into EVEX.LR
even for VEX (or XOP) encoded insns. Make operand size determination
use this right away, at the same time adding consistency checks for the
EVEX scalar insn cases (the non-scalar ones aren't uniform enough for
the checking to be done in a central place like this).

Note that the broadcast case is not handled here, but will be taken care
of elsewhere (in just a single place rather than at least two).

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2018-10-29 13:40:56 +01:00
Wei Liu 079df73c0a x86: put some code in arch_set_info_guest under CONFIG_PV
This function is called by both PV and HVM. Unfortunately the code is
very convoluted. We can reason that code between the call to
hvm_set_info_guest and out label is PV only. Put that portion under
CONFIG_PV.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
2018-10-28 20:01:58 +00:00
Wei Liu de5a2bdced x86: make mm.c build with !CONFIG_PV
Start by putting hypercall handlers which are supposed to be PV only
under CONFIG_PV. Shuffle some code around to avoid introducing
excessive numbers of CONFIG_PV.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
2018-10-28 20:01:37 +00:00
Jan Beulich 5d91b689dd x86emul: correct EVEX decoding
Fix an inverted pair of checks, drop an incorrect instance of #UD
raising for non-64-bit mode, and add further generic checks.

Note: Despite what SDM Vol 2 rev 067 states, EVEX.V' is _not_ ignored
      outside of 64-bit mode when the field does not encode a register.
      Just like EVEX.VVVV is required to be 0b1111 in that case, EVEX.V'
      is required to be 1 there.

Also rename the bcst field to br, as #UD generation for individual insns
will need to consider both of its possible meanings.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2018-10-26 17:50:01 +02:00
Jan Beulich 9f36c69284 x86emul/test: introduce eq()
In preparation for sensible to-boolean conversion on AVX512, wrap
another abstraction function around the present to_bool(<x> == <y>), to
get rid of the open-coded == (which will get in the way of using
built-in functions instead). For the future AVX512 use scalar operands
can't be used then anymore: Use (vec_t){} when the operand is zero,
and broadcast (if available) otherwise (assume pre-AVX512 when broadcast
is not available, in which case a plain scalar is still fine).

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2018-10-26 15:21:20 +02:00
Jan Beulich 304a8301fc x86emul: support AVX512 opmask insns
These are all VEX encoded, so the EVEX decoding logic continues to
remain unused at this point.

The new testcase is deliberately coded in assembly, as a C one would
have become almost unreadable due to the overwhelming amount of
__builtin_...() that would need to be used. After all the compiler has
no underlying type (yet) that could be operated on without builtins,
other than the vector types used for "normal" SIMD insns.

Note that outside of 64-bit mode and despite the SDM not currently
saying so, VEX.W is ignored for the KMOV{D,Q} encodings to/from GPRs,
just like e.g. for the similar VMOV{D,Q}.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2018-10-26 15:20:37 +02:00
Jan Beulich a14ca73359 x86: restrict HVMOP_pagetable_dying to current
This is not used (and probably was never meant to be) by the tool stack.
Limiting it to the current domain in particular allows to eliminate a
bogus use of vCPU 0 in pagetable_dying().

Remove the now unnecessary domain/vCPU parameters from the wrapper/hook
functions at the same time.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: George Dunlap <george.dunlap@citrix.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2018-10-26 15:18:52 +02:00
Jan Beulich 9c462cea68 x86: don't build guest-walk code without HVM and SHADOW_PAGING
It's dead code in that case.

We could go further, as we don't really need the 2- and 3-level walk
code in PV mode, but to drop their compilation requires quite a bit of
disentangling of shadow mode code.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
2018-10-26 15:16:23 +02:00
Andrew Cooper 35cd5ba367 x86/vvmx: Disallow the use of VT-x instructions when nested virt is disabled
c/s ac6a4500b "vvmx: set vmxon_region_pa of vcpu out of VMX operation to an
invalid address" was a real bugfix as described, but has a very subtle bug
which results in all VT-x instructions being usable by a guest.

The toolstack constructs a guest by issuing:

  XEN_DOMCTL_createdomain
  XEN_DOMCTL_max_vcpus

and optionally later, HVMOP_set_param to enable nested virt.

As a result, the call to nvmx_vcpu_initialise() in hvm_vcpu_initialise()
(which is what makes the above patch look correct during review) is actually
dead code.  In practice, nvmx_vcpu_initialise() first gets called when nested
virt is enabled, which is typically never.

As a result, the zeroed memory of struct vcpu causes nvmx_vcpu_in_vmx() to
return true before nested virt is enabled for the guest.

Fixing the order of initialisation is a work in progress for other reasons,
but not viable for security backports.

A compounding factor is that the vmexit handlers for all instructions, other
than VMXON, pass 0 into vmx_inst_check_privilege()'s vmxop_check parameter,
which skips the CR4.VMXE check.  (This is one of many reasons why nested virt
isn't a supported feature yet.)

However, the overall result is that when nested virt is not enabled by the
toolstack (i.e. the default configuration for all production guests), the VT-x
instructions (other than VMXON) are actually usable, and Xen very quickly
falls over the fact that the nvmx structure is uninitialised.

In order to fail safe in the supported case, re-implement all the VT-x
instruction handling using a single function with a common prologue, covering
all the checks which should cause #UD or #GP faults.  This deliberately
doesn't use any state from the nvmx structure, in case there are other lurking
issues.

This is XSA-278

Reported-by: Sergey Dyasli <sergey.dyasli@citrix.com>
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Sergey Dyasli <sergey.dyasli@citrix.com>
2018-10-24 22:16:11 +01:00
Ian Jackson be240aabb1 QEMU_TAG update 2018-10-24 16:18:37 +01:00
Andrew Cooper 46029da12e tools/dombuilder: Initialise vcpu debug registers correctly
In particular, initialising %dr6 with the value 0 is buggy, because on
hardware supporting Transactional Memory, it will cause the sticky RTM bit to
be asserted, even though a debug exception from a transaction hasn't actually
been observed.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
2018-10-24 14:43:05 +01:00
Andrew Cooper dfba4d2e91 x86/domain: Initialise vcpu debug registers correctly
In particular, initialising %dr6 with the value 0 is buggy, because on
hardware supporting Transactional Memory, it will cause the sticky RTM bit to
be asserted, even though a debug exception from a transaction hasn't actually
been observed.

Introduce arch_vcpu_regs_init() to set various architectural defaults, and
reuse this in the hvm_vcpu_reset_state() path.

Architecturally, %edx's init state contains the processors model information,
and 0xf looks to be a remnant of the old Intel processors.  We clearly have no
software which cares, seeing as it is wrong for the last decade's worth of
Intel hardware and for all other vendors, so lets use the value 0 for
simplicity.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
2018-10-24 14:43:05 +01:00
Andrew Cooper 721da6d41a x86/boot: Initialise the debug registers correctly
In particular, initialising %dr6 with the value 0 is buggy, because on
hardware supporting Transactional Memory, it will cause the sticky RTM bit to
be asserted, even though a debug exception from a transaction hasn't actually
been observed.

Move X86_DR6_DEFAULT into x86-defns.h along with the other architectural
register constants, and introduce a new X86_DR7_DEFAULT.  Use the existing
write_debugreg() helper, rather than opencoded inline assembly.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
2018-10-24 14:43:05 +01:00
Andrew Cooper e0b77cb77e SUPPORT: Correct the description of altp2m
Altp2m aids monitoring guest memory, not hypervisor memory.  Also, put its
common name in brackets to aid searching.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Razvan Cojocaru <rcojocaru@bitdefender.com>
Acked-by: Julien Grall <julien.grall@arm.com>
2018-10-23 17:29:17 +01:00
Ian Jackson 168f9d4960 tools/libfsimage: Set soname to 4.12 not 0.4.12
This was set to 0.4.12 by accident in
  c69a6aca85
    tools/libfsimage: Bump soname to 4.12

The extra 0. is harmless but ugly.  We should be somewhat consistent.

Reported-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
2018-10-23 14:57:24 +01:00
Sergey Dyasli 072e054359 x86/boot: enable NMIs after traps init
In certain scenarios, NMIs might be disabled during Xen boot process.
Such situation will cause alternative_instructions() to:

    panic("Timed out waiting for alternatives self-NMI to hit\n");

This bug was originally seen when using Tboot to boot Xen 4.11

To prevent this from happening, enable NMIs during cpu_init() and
during __start_xen() for BSP.

Signed-off-by: Sergey Dyasli <sergey.dyasli@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2018-10-23 12:33:54 +01:00
Wei Liu 76bfbcec42 arm: fix Dom0 creation after ef72c93df9
ARM Dom0 creation was broken by the said commit because ARM neither
provided XEN_DOMCTL_CDF_hvm_guest nor had CONFIG_PV set.

Set XEN_DOMCTL_CDF_hvm_guest flag for ARM Dom0 to fix the issue. Also
set XEN_DOMCTL_CDF_hap while at it.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: Julien Grall <julien.grall@arm.com>
2018-10-22 14:43:40 +01:00
Andrew Cooper 8cd9500958 xen/vsprintf: Introduce %*pb[l] for printing bitmaps
The format identifier is consistent with Linux.  The code is adapted from
bitmap_scn{,list}printf() but cleaned up.

This change allows all callers to avoid needing a secondary buffer to render a
cpumask/nodemask into.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: <jbeulich@suse.com>
2018-10-22 13:39:22 +01:00
Wei Liu 3528426cb9 x86: don't setup legacy syscall vector when !CONFIG_PV
The code snippet is to switch between SYS_DECS_trap_gate and
SYS_DESC_irq_gate depending on whether XPTI is used. When PV is
disabled there is no need to switch.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2018-10-22 12:31:09 +01:00
Wei Liu d7ccb75b96 x86: stub out PV only code in do_debug
When PV is disabled those symbols won't be available. It is impossible
for Xen to hit #DB there.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2018-10-20 12:31:48 +01:00
Wei Liu ef72c93df9 x86: connect guest creation with CONFIG_PV
This is a bit more complicated than the HVM case because system
domains have PV guest type. Leave them like that.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2018-10-20 12:31:48 +01:00
Wei Liu 6f407dc4fc x86/pv: make guest_io_{read,write} local functions
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2018-10-20 12:31:48 +01:00
Wei Liu 29b0678b3c x86: make construct_dom0 build with !CONFIG_PV
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2018-10-20 12:31:41 +01:00
Julien Grall 62aa9e7f1b xen/arm: Don't build GICv3 with the new vGIC
Commit 54ec59f6b0 "xen/arm: vgic-v3: Don't create empty re-distributor
regions" breaks compilation when using the new vGIC.

This is because the field nr_regions is not existing in the vgic
structure. For simplicity, as vGICv3 is not yet imported, disable GICv3.

Reported-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
2018-10-19 12:50:11 -07:00
Paul Durrant 3486f398a3 x86/hvm/ioreq: allow ioreq servers to use HVM_PARAM_[BUF]IOREQ_PFN
Since commit 2c257bd6 "x86/hvm: remove default ioreq server (again)" the
GFNs allocated by the toolstack and set in HVM_PARAM_IOREQ_PFN and
HVM_PARAM_BUFIOREQ_PFN have been unused. This patch allows them to be used
by (non-default) ioreq servers.

While in the area, also make sure HVM_PARAM_[BUF]IOREQ_PFN can only be set
once. These parameters should have always been in the 'set once' category
but this has, so far, not been enforced.

NOTE: This fixes a compatibility issue. A guest created on a version of
      Xen that pre-dates the initial ioreq server implementation and then
      migrated in will currently fail to resume because its migration
      stream will lack values for HVM_PARAM_IOREQ_SERVER_PFN and
      HVM_PARAM_NR_IOREQ_SERVER_PAGES *unless* the system has an
      emulator domain that uses direct resource mapping (which depends
      on the version of privcmd it happens to have) in which case it
      will not require use of GFNs for the ioreq server shared
      pages.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2018-10-19 13:41:55 +01:00
Andrew Cooper 00b1b8ed73 x86/svm: Remove the pdpe fields from struct vmcb
These fields have existed since the SVM code was first introduced.

The earliest reference I can find is c/s d1bd157fbc which is unforunately a
rebase & squash of a separate dev tree.  Looking a the commit message, I'm
guessing it was introduced by:

  > user:        twoller@xen-trw1.site
  > date:        Tue Dec 13 19:49:53 2005 -0500
  > files:       ... xen/include/asm-x86/svm_vmcb.h ...
  > description:
  > Add SVM base files to repository.

Anyway, the AMD SDM has no mention of PDPE fields in the VMCB and marks this
part of the VMCB as reserved.  The manual does explicitly say that 32bit PAE
paging may read the PDPE fields from memory rather from the CPU registers.

Chances are very good that this is a vestigial remnent of an early design.
Xen doesn't use the fields at all, except to copy them on virtual
vmentry/vmexit.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2018-10-17 17:50:14 +01:00