Commit Graph
559 Commits
Author SHA1 Message Date
Jan Beulich cf584d27f5 xen-mfndump: drop dead assignment to "page" from lookup_pte_func()
The variable isn't used past the loop, and its value also isn't
meaningful across iterations. Reduce its scope to make this more
obvious.

Coverity ID: 1532310
Fixes: ae763e4224 ("tools/misc: introduce xen-mfndump")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
Acked-by: Anthony PERARD <anthony.perard@citrix.com>
2023-06-14 12:31:02 +02:00
Olaf Hering 2f69ef9680 tools: fix make rpmball
Commit 438c5ffa44 ("rpmball: Adjust to
new rpm, do not require --force") attempted to handle stricter
directory permissions in newer distributions.

This introduced a few issues:
- /boot used to be a constant prior commit
  6475d70005 ("use BOOT_DIR as xen.gz
  install location"), since this commit the location has to be
  referenced via ${BOOT_DIR}
- it assumed the prefix and the various configurable paths match the
  glob pattern /*/*/*

Adjust the code to build a filelist on demand and filter directories
from an installed filesystem.rpm. This works on a SUSE system, and
will likely work on a RedHat based system as well.

Take the opportunity to replace the usage of $RPM_BUILD_ROOT with
%buildroot, and use pushd/popd pairs.

Signed-off-by: Olaf Hering <olaf@aepfle.de>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
2023-06-13 14:42:14 +02:00
Alejandro Vallejo 8347d6bb29 x86: Add bit definitions for Automatic IBRS
This is an AMD feature to reduce the IBRS handling overhead. Once enabled,
processes running at CPL=0 are automatically IBRS-protected even if
SPEC_CTRL.IBRS is not set. Furthermore, the RAS/RSB is cleared on VMEXIT.

The feature is exposed in CPUID and toggled in EFER.

Signed-off-by: Alejandro Vallejo <alejandro.vallejo@cloud.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2023-05-30 18:24:07 +01:00
Andrew Cooper ce8c930851 x86/cpu-policy: MSR_ARCH_CAPS feature names
Seed the default visibility from the dom0 special case, which for the most
part just exposes the *_NO bits.  EIBRS is the one non-*_NO bit, which is
"just" a status bit to the guest indicating a change in implemention of IBRS
which is already fully supported.

Insert a block dependency from the ARCH_CAPS CPUID bit to the entire content
of the MSR.  This is because MSRs have no structure information similar to
CPUID, and used by x86_cpu_policy_clear_out_of_range_leaves(), in order to
bulk-clear inaccessable words.

The overall CPUID bit is still max-only, so all of MSR_ARCH_CAPS is hidden in
the default policies.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2023-05-24 19:04:41 +01:00
Andrew Cooper d9fe459ffa x86/cpu-policy: Infrastructure for MSR_ARCH_CAPS
Bits through 24 are already defined, meaning that we're not far off needing
the second word.  Put both in right away.

As both halves are present now, the arch_caps field is full width.  Adjust the
unit test, which notices.

The bool bitfield names in the arch_caps union are unused, and somewhat out of
date.  They'll shortly be automatically generated.

Add CPUID and MSR prefixes to the ./xen-cpuid verbose output, now that there
are a mix of the two.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
2023-05-24 19:04:41 +01:00
Alejandro Vallejo 5b49f5e09d x86: Add AMD's CpuidUserDis bit definitions
AMD reports support for CpuidUserDis in CPUID and provides the toggle in HWCR.
This patch adds the positions of both of those bits to both xen and tools.

No functional change.

Signed-off-by: Alejandro Vallejo <alejandro.vallejo@cloud.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2023-05-11 13:12:46 +02:00
Alejandro Vallejo 3b5201e8cf tools: Use new xc function for some xc_domain_getinfo() calls
Move calls that require a information about a single precisely identified
domain to the new xc_domain_getinfo_single().

Signed-off-by: Alejandro Vallejo <alejandro.vallejo@cloud.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Anthony PERARD <anthony.perard@citrix.com>
2023-05-10 19:59:27 +01:00
Sergey Dyasli b95a72bb5b tools/xen-ucode: print information about currently loaded ucode
Add an option to xen-ucode tool to print the currently loaded ucode
revision and also print it during usage info.  Print CPU signature and
platform flags as well.  The raw data comes from XENPF_get_cpu_version
and XENPF_get_ucode_revision platform ops.

Example output:
    Intel: CPU signature 06-55-04 (raw 0x00050654) pf 0x1 revision 0x02006e05
      AMD: CPU signature 19-01-01 (raw 0x00a00f11) revision 0x0a0011ce

Signed-off-by: Sergey Dyasli <sergey.dyasli@citrix.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2023-05-03 18:36:46 +01:00
Jan Beulich 65c4e7472c x86emul: support AVX-NE-CONVERT insns
Matching what was done earlier, explicit tests are added only for
irregular insn / memory access patterns.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2023-04-17 18:11:45 +02:00
Jan Beulich 842acaa743 x86emul: support AVX-VNNI-INT8
These are close relatives of the AVX-VNNI ISA extension. Since the insns
here and in particular their memory access patterns follow the usual
scheme (and especially the byte variants of AVX-VNNI), I didn't think it
was necessary to add a contrived test specifically for them.

While making the addition also re-wire AVX-VNNI's handling to
simd_0f_ymm: There's no reason to check the AVX feature alongside the
one actually of interest (there are a few features where two checks are
actually necessary, e.g. GFNI+AVX, but this isn't the case here).

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2023-04-17 18:11:06 +02:00
Jan Beulich da232f1f11 x86emul: support AVX-IFMA insns
As in a few cases before (in particular: AVX512_IFMA), since the insns
here and in particular their memory access patterns follow the usual
scheme, I didn't think it was necessary to add a contrived test
specifically for them.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2023-04-17 18:10:14 +02:00
Juergen Gross 5b18843067 tools: rename xen-tools/libs.h file to common-macros.h
In order to better reflect the contents of the header and to make it
more appropriate to use it for different runtime environments like
programs, libraries, and firmware, rename the libs.h include file to
common-macros.h. Additionally add a comment pointing out the need to be
self-contained.

Suggested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com> # tools/python/xen/lowlevel/xc/xc.c
Acked-by: Christian Lindig <christian.lindig@cloud.com>
Acked-by: Anthony PERARD <anthony.perard@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
2023-03-22 09:57:19 +01:00
Andrew Cooper 1b00068420 tools: Delete trailing whitespace in python scripts
No functional change.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
Acked-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
2023-03-17 10:44:16 +00:00
Andrew Cooper 5d22d69b30 tools/misc: Drop xencons
This script is not python3 compatible, but has its shebang altered to say
python3 by INSTALL_PYTHON_PROG.

The most recent reference I can find to this script (which isn't incidental
adjustments in the makefile) is from the Xen book, fileish 561e30b804 which
says

  %% <snip>  Alternatively, if the
  %% Xen machine is connected to a serial-port server then we supply a
  %% dumb TCP terminal client, {\tt xencons}.

So this a not-invented-here version of telnet.  Delete it.

Resolves: xen-project/xen#159
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Anthony PERARD <anthony.perard@citrix.com>
Acked-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
2023-03-17 10:44:16 +00:00
Andrew Cooper 433d012c6c x86/sysctl: Retrofit XEN_SYSCTL_cpu_featureset_{pv,hvm}_max
Featuresets are supposed to be disappearing when the CPU policy infrastructure
is complete, but that has taken longer than expected, and isn't going to be
complete imminently either.

In the meantime, Xen does have proper default/max featuresets, and xen-cpuid
can even get them via the XEN_SYSCTL_cpu_policy_* interface, but only knows
now to render them nicely via the featureset interface.

Differences between default and max are a frequent source of errors,
frequently too in secret leading up to an embargo, so extend the featureset
sysctl to allow xen-cpuid to render them all nicely.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Christian Lindig <christian.lindig@cloud.com>
2023-03-13 11:26:26 +00:00
Andrew Cooper ec3474e1dd tools/xen-cpuid: Rework the handling of dynamic featuresets
struct fsinfo is the vestigial remnant of an older internal design which
didn't survive very long.

Simplify things by inlining get_featureset() and having a single memory
allocation that gets reused.  This in turn changes featuresets[] to be a
simple list of names, so rename it to fs_names[].

No functional change.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
2023-03-13 11:26:26 +00:00
Andrew Cooper 4a55779402 tools/xen-cpuid: Support dash as a bitmap separator
Xapi chose to render its featureset bitmaps with dashes rather than colons as
a separator.  Have xen-cpuid support both forms, for convenience.

Fix a trivial style issue in the vicinity while here.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
2023-03-13 11:26:26 +00:00
Andrew Cooper d04ae78c34 x86/spec-ctrl: Enumerations for DDP controls
https://www.intel.com/content/www/us/en/developer/articles/technical/software-security-guidance/technical-documentation/data-dependent-prefetcher.html

We should offer DDP-CTRL to guests, but I'm not sure when it is appearing in
hardware, and it's not massively urgent - the DDP behaviour is mostly sane
(having been designed in a post-spectre world) and this is a just-in-case
control.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2023-03-13 11:26:26 +00:00
Andrew Cooper 9276e832ae x86/spec-ctrl: Add BHI controls to userspace components
This was an oversight when adding the Xen parts.

Fixes: cea9ae0622 ("x86/spec-ctrl: Enumeration for new Intel BHI controls")
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2023-03-13 11:26:26 +00:00
Demi Marie Obenour a4557f515f change assorted xenbits.xen.org links to HTTPS
Also switch to xenbits.xenproject.org at this occasion.

Signed-off-by: Demi Marie Obenour <demi@invisiblethingslab.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
2023-02-28 14:52:14 +01:00
Andrew Cooper 01e7477d1b x86/shskt: Disable CET-SS on parts susceptible to fractured updates
Refer to Intel SDM Rev 70 (Dec 2022), Vol3 17.2.3 "Supervisor Shadow Stack
Token".

Architecturally, an event delivery which starts in CPL<3 and switches shadow
stack will first validate the Supervisor Shadow Stack Token (setting the busy
bit), then pushes CS/LIP/SSP.  One example of this is an NMI interrupting Xen.

Some CPUs suffer from an issue called fracturing, whereby a fault/vmexit/etc
between setting the busy bit and completing the event injection renders the
action non-restartable, because when it comes time to restart, the busy bit is
found to be already set.

This is far more easily encountered under virt, yet it is not the fault of the
hypervisor, nor the fault of the guest kernel.  The fault lies somewhere
between the architectural specification, and the uarch behaviour.

Intel have allocated CPUID.7[1].ecx[18] CET_SSS to enumerate that supervisor
shadow stacks are safe to use.  Because of how Xen lays out its shadow stacks,
fracturing is not expected to be a problem on native.

Detect this case on boot and default to not using shstk if virtualised.
Specifying `cet=shstk` on the command line will override this heuristic and
enable shadow stacks irrespective.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2023-02-09 18:26:17 +00:00
Andrew Cooper b4a23bf629 x86/cpuid: Infrastructure for leaves 7:1{ecx,edx}
We don't actually need ecx yet, but adding it in now will reduce the amount to
which leaf 7 is out of order in a featureset.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2023-02-09 18:26:17 +00:00
Andrew Cooper 80ff09ffe2 x86: Initial support for WRMSRNS
WRMSR Non-Serialising is an optimisation intended for cases where an MSR needs
updating, but architectural serialising properties are not needed.

In is anticipated that this will apply to most if not all MSRs modified on
context switch paths.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2023-01-20 19:39:33 +00:00
Andrew Cooper cd8fc0e9f3 x86/prot-key: Enumeration for Protection Key Supervisor
Protection Key Supervisor works in a very similar way to Protection Key User,
except that instead of a PKRU register used by the {RD,WR}PKRU instructions,
the supervisor protection settings live in MSR_PKRS and is accessed using
normal {RD,WR}MSR instructions.

PKS has the same problematic interactions with PV guests as PKU (more infact,
given the guest kernel's CPL), so we'll only support this for HVM guests for
now.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2023-01-20 19:39:33 +00:00
Andrew Cooper 24496558e6 x86/spec-ctrl: Enumeration for IBPB_RET
The IBPB_RET bit indicates that the CPU's implementation of MSR_PRED_CMD.IBPB
does flush the RSB/RAS too.

This is part of XSA-422 / CVE-2022-23824.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
2022-11-08 17:26:08 +00:00
Anthony PERARD 40d96f0c7d tools: Remove -Werror everywhere else
The previous changeset, e4f5949c44 ("tools: Add -Werror by default to all
tools/"), added "-Werror" to CFLAGS in tools/Rules.mk.  Remove it from
everywhere else now it is duplicated.

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
Acked-by: Daniel P. Smith <dpsmith@apertussolutions.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-acked-by: Henry Wang <Henry.Wang@arm.com>
2022-10-14 16:17:41 +01:00
Jan Beulich 4735553ec1 x86/CPUID: AVX512-FP16 definitions
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2022-08-11 11:45:23 +02:00
Andrew Cooper 76cb04ad64 x86/cpuid: Enumeration for BTC_NO
BTC_NO indicates that hardware is not succeptable to Branch Type Confusion.

Zen3 CPUs don't suffer BTC.

This is part of XSA-407.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2022-07-12 16:23:00 +01:00
Roger Pau Monné ae49ee66cf x86/cpuid: expose MCDT_NO to guests
Expose the MCDT_NO CPUID flag to guests if available.  The bit signals
that the CPU does not exhibit MCDT behavior, and as such can be
exposed without requiring any additional work.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2022-05-18 11:21:49 +02:00
Andrew Cooper 52ce1c9784 x86/spec-ctrl: Support Intel PSFD for guests
The Feb 2022 microcode from Intel retrofits AMD's MSR_SPEC_CTRL.PSFD interface
to Sunny Cove (IceLake) and later cores.

Update the MSR_SPEC_CTRL emulation, and expose it to guests.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2022-02-08 18:00:08 +00:00
Andrew Cooper f3709b15fc x86/cpuid: Infrastructure for cpuid word 7:2.edx
While in principle it would be nice to keep leaf 7 in order, that would
involve having an extra 5 words of zeros in a featureset.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2022-02-08 18:00:08 +00:00
Jan Beulich d940ce8e2a x86/Intel: use CPUID bit to determine PPIN availability
As of SDM revision 076 there is a CPUID bit for this functionality. Use
it to amend the existing model-based logic.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2022-01-27 17:38:15 +00:00
Jan Beulich e1828e3032 x86/cpuid: Infrastructure for leaf 7:1.ebx
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
2022-01-27 17:38:15 +00:00
Roger Pau Monné 2fc98a9587 libs/guest: move cpu policy related prototypes to xenguest.h
Do this before adding any more stuff to xg_cpuid_x86.c.

The placement in xenctrl.h is wrong, as they are implemented by the
xenguest library. Note that xg_cpuid_x86.c needs to include
xg_private.h, and in turn also fix xg_private.h to include
xc_bitops.h. The bitops definition of BITS_PER_LONG needs to be
changed to not be an expression, so that xxhash.h can use it in a
preprocessor if directive.

As a result also modify xen-cpuid to include xenguest.h.

Reported-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Anthony PERARD <anthony.perard@citrix.com>
2022-01-19 13:51:26 +01:00
Jan Beulich 6330e328ba tools/xen-detect: avoid possible pitfall with cpuid()
The 64-bit form forces %ecx to 0 while the 32-bit one so far didn't - it
only ended up that way when "pv_context" is zero. While presently no
leaf queried by callers has separate subleaves, let's avoid chancing it.

While there
- replace references to operands by number,
- relax constraints where possible,
- limit PUSH/POP to just the registers not also used as input,
all where applicable also for the 64-bit variant.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
2022-01-06 16:12:15 +01:00
Andrew Cooper 06cc1f886f tools/libxc: Drop copy-in in xc_physinfo()
The first thing XEN_SYSCTL_physinfo does is zero op->u.physinfo.

Do not copy-in.  It's pointless, and most callers don't initialise their
xc_physinfo_t buffer to begin with.  Remove the redundant zeroing from the
remaining callers.

Spotted by Coverity.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Wei Chen <Wei.Chen@arm.com>
Acked-by: Anthony PERARD <anthony.perard@citrix.com>
2022-01-05 09:44:26 +00:00
Jan Beulich af0c5430a8 xenperf: omit meaningless trailing zeroes from output
There's no point producing a long chain of zeroes when the previously
calculated total value was zero. To guard against mistakenly skipping
non-zero individual fields, widen "sum" to "unsigned long long".

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Anthony PERARD <anthony.perard@citrix.com>
2022-01-04 10:21:12 +01:00
Jan Beulich 5b3f42001a xenperf: name "newer" hypercalls
This table must not have got updated in quite a while; tmem_op for
example has managed to not only appear since then, but also disappear
again (adding a name for it nevertheless, to make more obvious that
something strange is going on if the slot would ever have a non-zero
value).

Also resolve arch_0 and arch_1 to more meaningful names on x86.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2022-01-04 10:16:48 +01:00
Anthony PERARD 41da0c21ee tools/misc: rework Makefile
Add missing "xen-detect" rule. It only works without it because we
still have make's built-ins rules and variables, but fix this to not
have to rely on them.

Rename $(TARGETS_BUILD) to $(TARGETS).

Remove the unused "build" target.

Also, they are no more "build-only" targets, remove the extra code.

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2021-12-16 20:27:13 +00:00
Anthony PERARD 725381a5ea xen: move include/asm-* to arch/*/include/asm
This avoid the need to create the symbolic link "include/asm".

Whenever a comment refer to an "asm" headers, this patch avoid
spelling the arch when not needed to avoid some code churn.

One unrelated change is to sort entries in MAINTAINERS for "INTEL(R)
VT FOR X86 (VT-X)"

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Acked-by: Paul Durrant <paul@xen.org>
Acked-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Julien Grall <jgrall@amazon.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2021-12-15 10:14:13 +01:00
Andrew Cooper 249e0f1d8f x86/cpuid: Fix TSXLDTRK definition
TSXLDTRK lives in CPUID leaf 7[0].edx, not 7[0].ecx.

Bit 16 in ecx is LA57.

Fixes: a6d1b55847 ("x86emul: support X{SUS,RES}LDTRK")
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2021-12-14 12:30:48 +00:00
Andrew Cooper 5d9974916b x86/cpufreq: Drop opencoded CPUID handling from powernow
Xen already collects CPUID.0x80000007.edx by default, meaning that we can
refer to per-cpu data directly.  This also avoids the need IPI the onlining
CPU to identify whether Core Performance Boost is available.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2021-11-29 13:53:05 +00:00
Andrew Cooper 747424c664 x86/amd: Enumeration for speculative features/hints
There is a step change in speculation protections between the Zen1 and Zen2
microarchitectures.

Zen1 and older have no special support.  Control bits in non-architectural
MSRs are used to make lfence be dispatch-serialising (Spectre v1), and to
disable Memory Disambiguation (Speculative Store Bypass).  IBPB was
retrofitted in a microcode update, and software methods are required for
Spectre v2 protections.

Because the bit controlling Memory Disambiguation is model specific,
hypervisors are expected to expose a MSR_VIRT_SPEC_CTRL interface which
abstracts the model specific details.

Zen2 and later implement the MSR_SPEC_CTRL interface in hardware, and
virtualise the interface for HVM guests to use.  A number of hint bits are
specified too to help guide OS software to the most efficient mitigation
strategy.

Zen3 introduced a new feature, Predictive Store Forwarding, along with a
control to disable it in sensitive code.

Add CPUID and VMCB details for all the new functionality.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2021-09-08 14:16:19 +01:00
Jane Malalane 5ae4120635 x86/cpuid: expose NullSelectorClearsBase CPUID bit to guests
AMD Zen3 adds the NullSelectorClearsBase bit to indicate that loading
a NULL segment selector zeroes the base and limit fields, as well as
just attributes.

Expose bit to all guests.

Suggested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jane Malalane <jane.malalane@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2021-09-07 09:40:25 +02:00
Andrew Cooper 79ca512a1f tools/tests: Drop obsolete mce-test infrastructure
mce-test has a test suite, but it depends on xend, needs to run in-tree, and
requires manual setup of at least one guest, and manual parameters to pass
into cases.  Drop the test infrasturcture.

Move the one useful remaining item, xen-mceinj, into misc/, fixing some minor
style issues as it goes.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
2021-07-09 16:38:27 +01:00
Tamas K Lengyel 2c7242bb2a tools/misc/xen-vmtrace: handle more signals and install by default
Signed-off-by: Tamas K Lengyel <tamas@tklengyel.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2021-07-09 16:38:25 +01:00
Andrew Cooper 3e09045991 x86/tsx: Cope with TSX deprecation on SKL/KBL/CFL/WHL
The June 2021 microcode is formally de-featuring TSX on the older Skylake
client CPUs.  The workaround from the March 2019 microcode is being dropped,
and replaced with additions to MSR_TSX_FORCE_ABORT to hide the HLE/RTM CPUID
bits.

With this microcode in place, TSX is disabled by default on these CPUs.
Backwards compatibility is provided in the same way as for TAA - RTM force
aborts, rather than suffering #UD, and the CPUID bits can be hidden to recover
performance.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2021-06-09 14:17:58 +01:00
Julien Grall 5605cfd49a tools/misc: Use const whenever we point to literal strings
literal strings are not meant to be modified. So we should use const
char * rather than char * when we we to store a pointer to them.

Signed-off-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
Acked-by: Wei Liu <wl@xen.org>
2021-05-18 14:54:05 +01:00
Andrew Cooper e19b01c186 libs/guest: Don't hide the indirection on xc_cpu_policy_t
It is bad form in C, perhaps best demonstrated by trying to read
xc_cpu_policy_destroy(), and causes const qualification to have
less-than-obvious behaviour (the hidden pointer becomes const, not the thing
it points at).

xc_cpu_policy_set_domain() needs to drop its (now normal) const qualification,
as the policy object is modified by the serialisation operation.

This also shows up a problem with the x86_cpu_policies_are_compatible(), where
the intermediate pointers are non-const.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
2021-05-05 20:20:42 +01:00
Roger Pau Monne 29736eaeae tools: switch existing users of xc_get_{system,domain}_cpu_policy
With the introduction of xc_cpu_policy_get_{system,domain} and
xc_cpu_policy_serialise the current users of
xc_get_{system,domain}_cpu_policy can be switched to the new
interface.

Note that xc_get_{system,domain}_cpu_policy is removed from the public
interface and the functions are made static, since there are still
internal consumers in xg_cpuid_x86.c

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2021-04-29 19:27:21 +01:00