Commit Graph
100 Commits
Author SHA1 Message Date
Jan Beulich 7a15cde90e update Xen version to 4.19.5 2026-03-26 14:21:54 +01:00
Jan Beulich 0e0bcd9a02 x86/S3: restore MCE (APs) init
MCE init for APs was broken when CPU feature re-checking was added. At the
same time make sure we don't bypass setup_doitm() (and whatever else may
be added to the bottom of identify_cpu()).

Fixes: bb502a8ca5 ("x86: check feature flags after resume")
Reported-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Tested-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
master commit: 5ebd4dd141
master date: 2026-03-24 12:05:42 +0100
2026-03-26 11:19:50 +01:00
Jan Beulich 360813e9e8 Revert "xen/mm: allow deferred scrub of physmap populate allocated pages"
This reverts commit 52f3b7c6f8 and its
prereq 49a4deb467 ("xen/mm: remove
aliasing of PGC_need_scrub over PGC_allocated"). Further fixes are
needed before this can be considered for backporting.
2026-03-26 11:16:58 +01:00
Jan Beulich a38f515168 domain: move vmtrace_alloc_buffer() invocation in vcpu_create()
The label used upon the function failing is wrong. Instead of correcting
the label, move the invocation up a little, to also avoid it altogether
for the idle domain (where ->vmtrace_size would be zero, and hence the
function would bail right away anyway).

Fixes: 217dd79ee2 ("xen/domain: Add vmtrace_size domain creation parameter")
Reported-by: Roger Pau Monné <roger.pau@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
master commit: adfbdaa347
master date: 2026-03-10 09:23:25 +0100
2026-03-10 14:45:42 +01:00
Jan Beulich b74f88c938 x86/MCE: restore CPU vendor reporting to the outside world
The records reported used to contain Linux enumerators. We first broke
that connection when purging unused ones, and then again when switching to
the bit mask forms.

Fixes: 4084130511 ("x86/cpu: Drop unused X86_VENDOR_* values")
Fixes: 0cd074144c ("x86/cpu: Renumber X86_VENDOR_* to form a bitmap")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
master commit: a94c5fd829
master date: 2026-02-23 08:39:58 +0100
2026-03-10 14:45:02 +01:00
Jan Beulich bd3a5c42c7 SUPPORT.md: extend security support "lifetime"
As per
https://lists.xen.org/archives/html/xen-devel/2026-02/msg00630.html.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2026-02-12 13:59:01 +01:00
Jan Beulich 2f7bd87bd4 PCI: handle PCI->PCIe bridges as well in free_pdev()
Don't know how I managed to overlook the freeing side when adding the case
to alloc_pdev().

Fixes: cd2b9f0b19 ("PCI: handle PCI->PCIe bridges as well in alloc_pdev()")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
master commit: 74f984159f
master date: 2026-02-02 09:06:42 +0100
2026-02-11 12:21:57 +01:00
Jan Beulich 7f9cde0f97 x86/EFI: correct symbol table generation with older GNU ld
See the extensive code comment. This isn't really nice, but unless I'm
overlooking something there doesn't look to be a way to have the linker
strip individual symbols while doing its work.

Fixes: bf6501a62e ("x86-64: EFI boot code")
Reported-by: Roger Pau Monné <roger.pau@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Daniel P. Smith <dpsmith@apertussolutions.com>
master commit: 45bb278934
master date: 2026-02-02 09:03:05 +0100
2026-02-11 12:21:47 +01:00
Jan Beulich 6b4480fe71 build/non-x86: fix symbol lookup in presence of build-id
It's not clear why only x86 had $(build_id_linker) applied to all three
linking passes. Not doing so will alter symbol offsets between the 2nd
and 3rd passes for, potentially, all of the symbols at higher addresses
(intermediate alignment padding may mask this effect, though, so it will
look as if problems appeared randomly).

Fixes: a353cab905 ("build_id: Provide ld-embedded build-ids")
Reported-by: Mykola Kvach <xakep.amatop@gmail.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Tested-by: Mykola Kvach <xakep.amatop@gmail.com> # arm
Reviewed-by: Oleksii Kurochko <oleksii.kurochko@gmail.com> # riscv
Tested-by: Jason Andryuk <jason.andryuk@amd.com> # arm64
Acked-by: Michal Orzel <michal.orzel@amd.com>
[jb: backport limited to Arm]
master commit: f0abe60de1
master date: 2026-01-27 10:26:36 +0100
2026-01-29 13:49:20 +01:00
Jan Beulich fad76f0d20 flask: fix gcov build with gcc14+
Gcc's "threading" of conditionals can lead to undue warnings, as reported
in e.g. https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116519 (no matter
that the overall situation is different there). While my gcc15 complains
("buf[2] may be used uninitialized in this function") about only two of
the three instances (not about the one in type_read()), adjust all three
to be on the safe side.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Daniel P. Smith <dpsmith@apertussolutions.com>
master commit: 7db4509d80
master date: 2026-01-26 10:34:14 +0100
2026-01-29 13:49:12 +01:00
Jan Beulich 91926059d5 PCI: handle PCI->PCIe bridges as well in alloc_pdev()
It's not clear why the enumerator was omitted, as these clearly shouldn't
take the "default" path (issuing a warning). Handle them the same as
legacy and PCIe->PCI bridges.

Fixes: e7e08d86ad ("IOMMU/PCI: consolidate pdev_type() and cache its result for a given device")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Stewart Hildebrand <stewart.hildebrand@amd.com>
master commit: cd2b9f0b19
master date: 2026-01-22 09:13:14 +0100
2026-01-29 13:48:52 +01:00
Jan Beulich 7482ce01cd x86/CPU: extend is_forced_cpu_cap()'s "reach"
"cpuid=no-rdrand" cannot actually be used to suppress the respective
boot warning on certain AMD hardware. That's because cleared_caps[] are
only applied after the ->c_init() hooks ran, i.e. cpu_has() still
returns true in init_amd().

Fixes: 93401e28a8 ("x86: clear RDRAND CPUID bit on AMD family 15h/16h")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: f09f2e28a9
master date: 2026-01-22 09:10:10 +0100
2026-01-29 13:48:20 +01:00
Jan Beulich 489b5bb0c2 x86/time: deal with negative deltas in get_s_time_fixed()
Callers may pass in TSC values from before the local TSC stamp was last
updated (this would in particular be the case when the TSC was latched, a
time rendezvous occurs, and the latched value is used only afterwards).
scale_delta(), otoh, deals with unsigned values, and hence would treat
negative incoming deltas as huge positive values, yielding entirely bogus
return values.

Fixes: 88e64cb785 ("x86/HVM: use fixed TSC value when saving or restoring domain")
Reported-by: Антон Марков <akmarkov45@gmail.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
master commit: 7b3e1b4e84
master date: 2026-01-20 09:03:17 +0100
2026-01-29 13:48:02 +01:00
Jan Beulich a9d58e5e40 x86/shadow: don't overrun trace_emul_write_val
Guests can do wider-than-PTE-size writes on page tables. The tracing
helper variable, however, only offers space for a single PTE (and it is
being switched to the more correct type right here). Therefore bound
incoming write sizes to the amount of space available.

To not leave dead code (which is a Misra concern), drop the now unused
guest_pa_t as well.

Also move and adjust GUEST_PTE_SIZE: Derive it rather than using hard-
coded numbers, and put it in the sole source file where it's actually
needed. This then also addresses a Misra rule 20.9 ("All identifiers
used in the controlling expression of #if or #elif preprocessing
directives shall be #define'd before evaluation") violation:
GUEST_PAGING_LEVELS is #define'd only in multi.c.

This is XSA-477 / CVE-2025-58150.

Fixes: 9a86ac1aa3 ("xentrace 5/7: Additional tracing for the shadow code")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: a6626b613a
master date: 2026-01-27 13:55:01 +0100
2026-01-27 14:05:04 +01:00
Jan Beulich bc8363a41a x86/PVH: mark pvh_setup_mmcfg() __init
Its sole caller is, and the wrong annotation would cause a build failure
(non-empty .text) if the compiler chose to not inline the function when at
the same time LATE_HWDOM=y.

Fixes: be52cb139f ("x86/mmcfg: add handlers for the PVH Dom0 MMCFG areas")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
master commit: bdd5f35cf2
master date: 2026-01-08 11:05:30 +0100
2026-01-13 15:50:54 +01:00
Jan Beulich c2affd2788 x86/mm: update log-dirty bitmap when manipulating P2M
Just like for PV guests MMU_MACHPHYS_UPDATE implies marking of the
respective page as dirty, additions to a HVM guest's P2M should do so.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
[jb: backport limited to the new paging_mark_pfn_dirty() use]
master commit: 98fccdf0ac
master date: 2025-12-11 09:50:30 +0100
2026-01-13 15:49:30 +01:00
Jan Beulich 331ffed3cf update Xen version to 4.19.5-pre 2026-01-13 15:48:11 +01:00
Jan Beulich ac1c1fb9e8 update Xen version to 4.19.4 2025-12-04 10:51:21 +01:00
Jan Beulich d1c28ed259 x86emul/test: correct compiler checking and avoid it when merely cleaning
The error messages that the compiler may emit can be confusing.

The check was also the wrong way round in case multiple make targets are
specified: We want to do the check whenever targets other than the running
and cleaning ones are specified.

Fixes: 05f4cc2192 ("x86emul: suppress default test harness build with incapable compiler")
Fixes: d5997399b7 ("x86emul: suppress "not built" warning for test harness'es run targets")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: c482d1f59f
master date: 2025-11-24 11:28:47 +0100
2025-11-25 09:39:41 +01:00
Jan Beulich e2f2beb921 x86emul/test: extend cleaning of generated files
Many *.c files are symlinked while building, so along with generated *.h
files they ought to be removed. Conversely $(TARGET) doesn't need removing
twice.

Fixes: cb4fcf70b2 ("x86emul: parallelize SIMD test code building")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 774c382b28
master date: 2025-11-13 09:08:27 +0100
2025-11-25 09:38:33 +01:00
Jan Beulich f17288c3e0 x86/HPET: replace handle_hpet_broadcast()'s on-stack cpumask_t
With large NR_CPUS on-stack cpumask_t variables are problematic. Now that
the IRQ handler can't be invoked in a nested manner anymore, we can
instead use a per-CPU variable. While we can't use scratch_cpumask in code
invoked from IRQ handlers, simply amend that one with a HPET-special form.
(Note that only one of the two IRQ handling functions can come into play
at any one time.)

Fixes: 996576b965 ("xen: allow up to 16383 cpus")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
master commit: 80c7c67164
master date: 2025-10-29 09:02:53 +0100
2025-11-10 16:04:46 +01:00
Jan Beulich 1991582925 x86/HPET: use single, global, low-priority vector for broadcast IRQ
Using dynamically allocated / maintained vectors has several downsides:
- possible nesting of IRQs due to the effects of IRQ migration,
- reduction of vectors available for devices,
- IRQs not moving as intended if there's shortage of vectors,
- higher runtime overhead.

As the vector also doesn't need to be of any priority (first and foremost
it really shouldn't be of higher or same priority as the timer IRQ, as
that raises TIMER_SOFTIRQ anyway), simply use the lowest one above the
legacy range. The vector needs reserving early, until it is known whether
it actually is used. If it isn't, it's made available for general use.

With a fixed vector, less updating is now necessary in
set_channel_irq_affinity(); in particular channels don't need transiently
masking anymore, as the necessary update is now atomic. To fully leverage
this, however, we want to stop using hpet_msi_set_affinity() there. With
the transient masking dropped, we're no longer at risk of missing events.

AMD interrupt remapping code so far didn't "return" a consistent MSI
address when translating an MSI message. Clear respective fields there, to
keep the related assertion in set_channel_irq_affinity() from triggering.

Fixes: 996576b965 ("xen: allow up to 16383 cpus")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
master commit: 8ef32772b5
master date: 2025-10-27 15:51:42 +0100
2025-11-10 16:03:41 +01:00
Jan Beulich 6a4add3bd9 x86/HPET: deal with unused channels
Keeping channels enabled when they're unused is only causing problems:
Extra interrupts harm performance, and extra nested interrupts could even
have caused worse problems. However, on all Intel hardware I looked at
closely, a 0->1 transition of the enable bit causes an immediate IRQ.
Hence disabling channels isn't a good idea there. Set a "long" timeout
instead.

Along with that also "clear" the channel's "next event", for it to be
properly written by whatever the next user is going to want (possibly
avoiding too early an IRQ).

Further, along the same lines, don't enable channels early when starting
up an IRQ. This doesn't need to happen earlier than from
set_channel_irq_affinity() (once a channel goes into use the very first
time). This eliminates a single instance of

(XEN) [VT-D]INTR-REMAP: Request device [0000:00:1f.0] fault index 0
(XEN) [VT-D]INTR-REMAP: reason 25 - Blocked a compatibility format interrupt request

during boot. (Why exactly there's only one instance, when we use multiple
counters and hence multiple IRQs, I can't tell. My understanding would be
that this was due to __hpet_setup_msi_irq() being called only after
request_irq() [and hence the .startup handler], yet that should have
affected all channels.)

Fixes: 3ba523ff95 ("CPUIDLE: enable MSI capable HPET for timer broadcast")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
master commit: 24f608dc90
master date: 2025-10-27 15:51:03 +0100
2025-11-10 16:03:15 +01:00
Jan Beulich de92f0973c AMD/IOMMU: unshare IRQ .ack and .disable handlers
A .disable handler can't typically be re-used for .ack: The latter needs
to deal with IRQ migration, while the former shouldn't. Furthermore
invoking just irq_complete_move() isn't enough; one of
move_{native,masked}_irq() also needs invoking.

Fixes: 487a1cffd7 ("x86: Implement per-cpu vector for xen hypervisor")
Fixes: f821102450 ("x86: IRQ Migration logic enhancement")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
master commit: aed6278b2a
master date: 2025-10-21 14:11:45 +0200
2025-11-10 16:02:58 +01:00
Jan Beulich ed86adbd7e symbols: discard stray file symbols
By observation GNU ld 2.25 may emit file symbols for .data.read_mostly
when linking xen.efi. Due to the nature of file symbols in COFF symbol
tables (see the code comment) the symbols_offsets[] entries for such
symbols would cause assembler warnings regarding value truncation. Of
course the resulting entries would also be both meaningless and useless.
Add a heuristic to get rid of them, really taking effect only when
--all-symbols is specified (otherwise these symbols are discarded
anyway).

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
master commit: 2f21ce1a6a
master date: 2025-10-21 14:10:46 +0200
2025-11-10 16:02:39 +01:00
Jan Beulich de5a58a22e VT-d: check bus_to_context_maddr()'s return value
The function returning zero is an error indication; we shouldn't try to
map MFN 0 and then treat that page as a context table.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: ef5b718cf8
master date: 2025-10-13 16:50:01 +0200
2025-10-21 15:28:19 +02:00
Jan Beulich 117df42191 x86/HWP: adjust feature_hdc's section annotation
The variable can be cleared (set to false) by a non-init function's error
path (hwp_init_msrs()).

Fixes: 99c4570f82 ("cpufreq: Add Hardware P-State (HWP) driver")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
master commit: 4676e09b3c
master date: 2025-10-13 10:41:35 +0200
2025-10-21 15:28:08 +02:00
Jan Beulich e9e054a161 Arm: adjust locking in p2m_get_page_from_gfn()
In order to safely acquire a reference for a foreign page mapping, the
P2M lock needs to be held until we have the reference in hand (or
getting one failed). Otherwise the page can change P2M type and
ownership in between.

This is CVE-2025-58145 / part of XSA-473.

Fixes: 9486a8d07b ("xen/arm: Handle remove foreign mapping")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
master commit: 2275bf83a1
master date: 2025-09-09 14:12:57 +0200
2025-09-09 14:23:32 +02:00
Jan Beulich 8634f3ef06 Arm: foreign page handling in p2m_get_page_from_gfn()
I can't see what would make the 1st of the assertions safe: For example,
the P2M lock not being held, the foreign page may disappear before we
get to call page_get_owner_and_reference(), which hence may return NULL.

Even the 2nd, which appears to be safe safe, is lacking proper release
build fallbacks.

Drop the former in favor of an if(), and convert the latter to the
equivalent of what x86 uses: ASSERT_UNREACHABLE() plus putting of the
obtained page.

This is CVE-2025-58144 / part of XSA-473.

Fixes: 9486a8d07b ("xen/arm: Handle remove foreign mapping")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
master commit: c5a6dd6850
master date: 2025-09-09 14:12:13 +0200
2025-09-09 14:23:23 +02:00
Jan Beulich f41d24890f x86/gen-cpuid: correct cycle detection
With the processing done linearly (rather than recursively), checking
whether any of the features was previously seen is wrong: That would
e.g. trigger for this simple set of dependencies

    X: [A, B]
    A: [C]
    B: [C]

(observed in reality when making AMX-AVX512 dependent upon both
AMX-TILE and AVX512F, causing XSAVE to see AMX-AVX512 twice in its list
of dependents). But checking the whole accumulated set also isn't
necessary - just checking the feature we're processing dependents of is
sufficient. We may detect a cycle later that way, but we still will
detect it. What we need to avoid is adding a feature again when we've
already seen it.

As a result, seeding "seen[]" with "feat" isn't necessary anymore.

Fixes: fe4408d180 ("xen/x86: Generate deep dependencies of features")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 3999ff0d30
master date: 2025-09-01 13:07:53 +0200
2025-09-03 14:07:50 +02:00
Jan Beulich 9876248a54 x86/mkelf32: pad load segment to 2Mb boundary
In order to legitimately set up initial mappings past _end[], we need
to make sure that the entire mapped range is inside a RAM region.
Therefore we need to inform the bootloader (or alike) that our allocated
size is larger than just the next SECTION_ALIGN-ed boundary past _end[].

This allows dropping a command line option from the tool, which was
introduced to work around a supposed linker bug, when the problem was
really Xen's.

While adjusting adjacent code, correct the argc check to also cover the
case correctly when --notes was passed.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
master commit: 4fb075201f
master date: 2025-08-18 10:42:24 +0200
2025-09-03 14:05:18 +02:00
Jan Beulich 7f149db6e8 update Xen version to 4.19.4-pre 2025-09-03 14:04:06 +02:00
Jan Beulich 077419f04a update Xen version to 4.19.3 2025-08-04 17:20:48 +02:00
Jan Beulich a592800e5e xenalyze: correct symbol name length fscanf() specifier
SYMBOL_NAME_SIZE is 124, not 128. Use the symbolic name there as well,
to avoid any disconnect.

While there correct indentation on the following line as well.

Coverity ID: 1659391
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Alejandro Vallejo <alejandro.garciavallejo@amd.com>
Acked-by: Anthony PERARD <anthony.perard@vates.tech>
master commit: dfabb3fee3
master date: 2025-07-31 14:44:02 +0200
2025-08-04 15:22:58 +02:00
Jan Beulich e13e729e3b x86/alternatives: serialize after (self-)modifying code
While supposedly safe via enforcing a control flow change when modifying
already prefetched code, it may not really be. Afaik a request is
pending to drop the first of the two options in the SDM's "Handling
Self- and Cross-Modifying Code" section (still present there as of
version 087). Insert a serializing instruction there, and remove the
"noinline" in exchange.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
master commit: c5b06d0b1b
master date: 2025-07-23 15:17:28 +0200
2025-07-31 09:52:17 +02:00
Jan Beulich 92ba71bf8b x86/S3: don't lose previously collected CPU data (AMD extra)
smp_store_cpu_info() doesn't call identify_cpu() again during S3 resume,
hence it is wrong to zap APs' data while bringing them down (and we're
not just parking them there) during suspend.

Fixes: bb502a8ca5 ("x86: check feature flags after resume")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
master commit: 55719030b0
master date: 2025-07-17 17:55:54 +0200
2025-07-22 12:43:10 +02:00
Jan Beulich e0ef14b32e x86/S3: don't lose previously collected CPU data
smp_store_cpu_info() doesn't call identify_cpu() again during S3 resume,
hence it is wrong to overwrite APs' data using boot_cpu_data. With
7126b7f806 ("x86/CPU: re-work populating of cpu_data[]") this now
results in a crash, as the cpu_to_socket() use in smp_store_cpu_info()
then obtains a bad socket number, much like was already observed in [1].

[1] https://lists.xen.org/archives/html/xen-devel/2025-06/msg01879.html

Fixes: bb502a8ca5 ("x86: check feature flags after resume")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
master commit: acaa69d985
master date: 2025-07-17 12:49:18 +0200
2025-07-22 10:00:00 +02:00
Jan Beulich 687ae6747d x86/SMP: guard socket_cpumask[] access in cpu_smpboot_free()
Before CPU identification has run (and it may not have run at all e.g.
when AP bringup failed altogether), cpu_data[].phys_proc_id (which is
what cpu_to_socket() resolves to) can't really be used. The use of
cpu_to_socket()'s result as an array index in cpu_smpboot_free()
therefore needs guarding, as the function will also be invoked upon AP
bringup failure, in which case CPU identification may not have run.

Without "x86/CPU: re-work populating of cpu_data[]" [1] the issue is
less pronounced: The field starts out as zero, then has the BSP value
(likely again zero) copied into it, and it is properly invalidated only
in cpu_smpboot_free(). Still it is clearly wrong to use the BSP's socket
number here.

Making the guard work with and without the above patch applied turns out
interesting: Prior to that patch, the sole invalidation done is that in
cpu_smpboot_free(). Upon a later bringup attempt, the fields invalidated
are overwritten by the BSP values again, though. Hence compare APIC IDs,
as they cannot validly be the same once CPU identification has run.

[1] https://lists.xen.org/archives/html/xen-devel/2024-02/msg00727.html

Fixes: 4824bdfdab ("x86: add socket_cpumask")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
master commit: 8c15d3d187
master date: 2025-07-17 12:47:04 +0200
2025-07-22 09:59:35 +02:00
Jan Beulich 7192153f97 x86emul: adjust BSF/BSR/LZCNT/TZCNT behavior as to EFLAGS
SDM revision 088 points out that apparently as of quite some time ago on
Intel hardware BSF and BSR may alter all arithmetic flags, not just ZF.
Because of the inconsistency (sometimes even errata, and because
documentation doesn't look to be quite right about PF), best we can do
is simply take the flag values from what the processor produces, just
like we do for various other arithmetic insns. (Note also that AMD and
Intel have always been disagreeing on arithmetic flags other than ZF.)
To be both safe (against further anomalies) and consistent, extend this
to {L,T}ZCNT as well. (Emulating the two insns correctly even when
underlying hardware doesn't support it was perhaps nice, but yielded
guest-observable inconsistencies.)

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 37a55e69c7
master date: 2025-07-16 12:51:26 +0200
2025-07-22 09:59:16 +02:00
Jan Beulich b026848daf x86/idle: undo use of MONITOR/MWAIT mnemonics
While the change is fine on staging, where the toolchain baseline was
moved, we need to remain compatible with older gas on stable branches
for now.

Fixes: fa254938f0 ("x86/idle: Move monitor()/mwait() wrappers into cpu-idle.c")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
2025-07-09 12:18:46 +02:00
Jan Beulich 79ec6818da xen/build: pass -fzero-init-padding-bits=all to gcc15
See the respective bullet point in the Caveats section of
https://gcc.gnu.org/gcc-15/changes.html.

While I'm unaware of us currently relying on the pre-gcc15 behavior,
let's still play safe and retain what unknowingly we may have been
relying upon.

According to my observations, on x86 generated code changes
- somewhere deep in modify_bars(), presumably from the struct map_data
  initializer in apply_map() (a new MOVQ),
- in vpci_process_pending(), apparently again from the struct map_data
  initializer (and again a new MOVQ),
- near the top of find_cpio_data(), presumably from the struct cpio_data
  initializer (a MOVW changing to a MOVQ).

Requested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 86da14178d
master date: 2025-07-01 11:23:59 +0200
2025-07-07 11:35:48 +02:00
Jan Beulich 43aeacff86 x86/IRQ: constrain creator-domain-ID assertion
If init_one_irq_desc() fails, ->arch.creator_domid won't be set to the
expected value, and hence the assertion may trigger. Limit it to just
the success case of that function call.

Fixes: 92d9101eab ("x86: allow stubdom access to irq created for msi")
Reported-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
master commit: d7127e06f6
master date: 2025-05-14 11:00:00 +0200
2025-05-15 09:07:06 +02:00
Jan Beulich 2b92925c6d cpufreq: don't leave stale statistics pointer
Error paths of cpufreq_statistic_init() correctly free the base
structure pointer, but the per-CPU variable would still hold it, mis-
guiding e.g. cpufreq_statistic_update(). Defer installing of the pointer
there until the structure was fully populated.

Fixes: 755af07edb ("x86/cpufreq: don't use static array for large per-CPU data structures")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: a1ce987411
master date: 2025-04-30 08:47:49 +0200
2025-05-13 13:58:33 +02:00
Jan Beulich f33ff85f21 x86emul: avoid UB shifts in FLDENV/FRSTOR handling
16-bit quantities, no matter whether expressed as uint16_t or as
bitfield, will be promoted to plain int before doing any arithmetic on
them. Shifting such values by 16 will therefore shift into the sign bit,
which is UB if that bit becomes set. To account for all reads and all
writes accessing opposite members of the same union, introduce yet more
local variables to reduce the shift counts to 12.

Fixes: be55ed744e ("x86emul: support FLDENV and FRSTOR")
Reported-by: Fabian Specht <f.specht@tum.de>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
master commit: d00fc019b6
master date: 2025-04-30 08:46:21 +0200
2025-05-13 13:58:17 +02:00
Jan Beulich 58ab9fcc3f x86/thunk: Build Xen with Return Thunks
The Indirect Target Selection speculative vulnerability means that indirect
branches (including RETs) are unsafe when in the first half of a cacheline.

In order to mitigate this, build with return thunks and arrange for
__x86_return_thunk to be (mis)aligned in the same manner as
__x86_indirect_thunk_* so the RET instruction is placed in a safe location.

place_ret() needs to conditionally emit JMP __x86_return_thunk instead of RET.

This is part of XSA-469 / CVE-2024-28956

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
(cherry picked from commit afcb4a06c7)
2025-05-12 17:29:13 +01:00
Jan Beulich 545eba29ac x86/thunk: (Mis)align __x86_indirect_thunk_* to mitigate ITS
The Indirect Target Selection speculative vulnerability means that indirect
branches (including RETs) are unsafe when in the first half of a cacheline.

Arrange for __x86_indirect_thunk_* to always be in the second half.

This is part of XSA-469 / CVE-2024-28956

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
(cherry picked from commit d293cc9da9)
2025-05-12 17:29:13 +01:00
Jan Beulich e2adda16e0 compat/memory: avoid UB shifts in XENMEM_exchange handling
Add an early basic check, yielding the same error code as the more
thorough one the main handler would produce.

Fixes: b8a7efe852 ("Enable compatibility mode operation for HYPERVISOR_memory_op")
Reported-by: Manuel Andreas <manuel.andreas@tum.de>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 560c51be8f
master date: 2025-04-22 11:25:23 +0200
2025-04-29 11:57:07 +02:00
Jan Beulich 9466bb1dc8 x86emul: also clip repetition count for STOS
Like MOVS, INS, and OUTS, STOS also has a special purpose hook, where
the hook function may legitimately have the same expectation as to the
request not straddling address space start/end.

Fixes: 5dfe4aa4ee ("x86_emulate: Do not request emulation of REP instructions beyond the")
Reported-by: Fabian Specht <f.specht@tum.de>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 8c5636b6c8
master date: 2025-04-22 11:24:20 +0200
2025-04-29 11:56:44 +02:00
Jan Beulich 7ffef37f55 x86/HVM: update repeat count upon nested lin->phys failure
For the X86EMUL_EXCEPTION case the repeat count must be correctly
propagated back. Since for the recursive invocation we use a local
helper variable, its value needs copying to the caller's one.

While there also correct the off-by-1 range in the comment ahead of the
function (strictly speaking for the "DF set" case we'd need to put
another, different range there as well).

Fixes: 53f87c03b4 ("x86emul: generalize exception handling for rep_* hooks")
Reported-by: Manuel Andreas <manuel.andreas@tum.de>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: c07b16fd6e
master date: 2025-04-17 10:01:19 +0200
2025-04-29 11:56:25 +02:00
Jan Beulich 593c437778 include: sort $(wildcard ...) results
The order of items is stored in .*.chk.cmd, and hence variations between
how items are ordered would result in re-invocation of the checking rule
during "make install-xen" despite that already having successfully run
earlier on. The difference can become noticable when building (as non-
root) and installing (as root) use different GNU make versions: In 3.82
the sorting was deliberately undone, just for it to be restored in 4.3.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: ff835bbc80
master date: 2025-04-10 10:56:29 +0200
2025-04-29 11:55:16 +02:00
Jan Beulich ae562bee69 x86/MTRR: hook mtrr_bp_restore() back up
Unlike stated in the offending commit's description,
load_system_tables() wasn't the only thing left to retain from the
earlier restore_rest_processor_state(). Note that MTRR state was still
reloaded via mtrr_aps_sync_end(), but that happens quite a bit later in
the resume process.

While there also do Misra-related tidying for the function itself: The
function being used from assembly only means it doesn't need to have a
declaration, but wants to be asmlinkage.

Fixes: 4304ff420e ("x86/S3: Drop {save,restore}_rest_processor_state() completely")
Reported-by: Roger Pau Monné <roger.pau@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
master commit: 0414dedd6f
master date: 2025-04-03 09:39:13 +0200
2025-04-29 11:52:22 +02:00
Jan Beulich 7d82789238 update Xen version to 4.19.3-pre 2025-04-29 11:51:42 +02:00
Jan Beulich f3362182e0 update Xen version to 4.19.2 2025-04-04 12:47:23 +02:00
Jan Beulich 30eb7e6ad8 x86/P2M: synchronize fast and slow paths of p2m_get_page_from_gfn()
Handling of both grants and foreign pages was different between the two
paths.

While permitting access to grants would be desirable, doing so would
require more involved handling; undo that for the time being. In
particular the page reference obtained would prevent the owning domain
from changing e.g. the page's type (after the grantee has released the
last reference of the grant). Instead perhaps another reference on the
grant would need obtaining. Which in turn would require determining
which grant that was.

Foreign pages in any event need permitting on both paths.

Introduce a helper function to be used on both paths, such that
respective checking differs in just the extra "to be unshared" condition
on the fast path.

While there adjust the sanity check for foreign pages: Don't leak the
reference on release builds when on a debug build the assertion would
have triggered. (Thanks to Roger for the suggestion.)

Fixes: 80ea7af172 ("x86/mm: Introduce get_page_from_gfn()")
Fixes: 50fe6e7370 ("pvh dom0: add and remove foreign pages")
Fixes: cbbca7be4a ("x86/p2m: make p2m_get_page_from_gfn() handle grant case correctly")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
master commit: a8325f981c
master date: 2025-03-31 09:21:12 +0200
2025-04-02 14:28:08 +02:00
Jan Beulich edf9509e4d Arm/domctl: correct XEN_DOMCTL_vuart_op error return value
copy_to_guest() returns the number of bytes not copied; that's not what
the function should return to its caller though. Convert to returning
-EFAULT instead.

Fixes: 86039f2e8c ("xen/arm: vpl011: Add a new domctl API to initialize vpl011")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Michal Orzel <michal.orzel@amd.com>
master commit: 341c0df40b
master date: 2025-03-27 12:22:39 +0100
2025-03-27 15:06:53 +01:00
Jan Beulich 46da7056e4 x86/pmstat: correct get_cpufreq_para()'s error return value
copy_to_guest() returns the number of bytes not copied; that's not what
the function should return to its caller though. Convert to returning
-EFAULT instead.

Fixes: 7542c4ff00 ("Add user PM control interface")
Reported-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 855337ca49
master date: 2025-03-27 12:22:06 +0100
2025-03-27 15:06:45 +01:00
Jan Beulich 43e1996c02 x86/PVH: account for module command line length
As per observation in practice, initrd->cmdline_pa is not normally zero.
Hence so far we always appended at least one byte. That alone may
already render insufficient the "allocation" made by find_memory().
Things would be worse when there's actually a (perhaps long) command
line.

Skip setup when the command line is empty. Amend the "allocation" size
by padding and actual size of module command line. Along these lines
also skip initrd setup when the initrd is zero size.

Fixes: 0ecb8eb09f ("x86/pvh: pass module command line to dom0")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
master commit: 989584e532
master date: 2025-03-27 12:21:08 +0100
2025-03-27 15:06:33 +01:00
Jan Beulich c9f077bc41 x86/PVH: expose OEMx ACPI tables to Dom0
What they contain we don't know, but we can't sensibly hide them. On my
Skylake system OEM1 (with a description of "INTEL  CPU EIST") is what
contains all the _PCT, _PPC, and _PSS methods, i.e. about everything
needed for cpufreq. (_PSD interestingly are in an SSDT there.)

Further OEM2 there has a description of "INTEL  CPU  HWP", while OEM4
has "INTEL  CPU  CST". Pretty clearly all three need exposing for
cpufreq and cpuidle to work.

Fixes: 8b1a5268da ("pvh/dom0: whitelist PVH Dom0 ACPI tables")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
master commit: 6378909b41
master date: 2025-03-26 12:32:03 +0100
2025-03-27 15:05:11 +01:00
Jan Beulich 748be9a974 xenpm: sanitize allocations in show_cpufreq_para_by_cpuid()
malloc(), when passed zero size, may return NULL (the behavior is
implementation defined). Mirror the ->gov_num check to the other two
allocations as well. Don't chance then actually using a NULL in
print_cpufreq_para().

Fixes: 75e06d089d ("xenpm: add cpu frequency control interface, through which user can")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
master commit: 6c0dc87bb0
master date: 2025-03-26 12:30:57 +0100
2025-03-27 15:04:48 +01:00
Jan Beulich 3f73662226 libxl: avoid infinite loop in libxl__remove_directory()
Infinitely retrying the rmdir() invocation makes little sense. While the
original observation was the log filling the disk (due to repeated
"Directory not empty" errors, in turn occurring for unclear reasons),
the loop wants breaking even if there was no error message being logged
(much like is done in the similar loops in libxl__remove_file() and
libxl__remove_file_or_directory()).

Fixes: c4dcbee67e ("libxl: provide libxl__remove_file et al")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Acked-by: Anthony PERARD <anthony.perard@vates.tech>
master commit: 68baeb5c48
master date: 2025-03-13 10:23:10 +0100
2025-03-20 13:20:06 +01:00
Jan Beulich f2c5b4b1aa IOMMU/x86: the bus-to-bridge lock needs to be acquired IRQ-safe
The function's use from set_msi_source_id() is guaranteed to be in an
IRQs-off region. While the invocation of that function could be moved
ahead in msi_msg_to_remap_entry() (doesn't need to be in the IOMMU-
intremap-locked region), the call tree from map_domain_pirq() holds an
IRQ descriptor lock. Hence all use sites of the lock need become IRQ-
safe ones.

In find_upstream_bridge() do a tiny bit of tidying in adjacent code:
Change a variable's type to unsigned and merge a redundant assignment
into another variable's initializer.

This is XSA-467 / CVE-2025-1713.

Fixes: 476bbccc81 ("VT-d: fix MSI source-id of interrupt remapping")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
(cherry picked from commit 39bc6af3ba)
2025-02-27 12:59:57 +00:00
Jan Beulich 46e3e9d739 radix-tree: introduce RADIX_TREE{,_INIT}()
... now that static initialization is possible. Use RADIX_TREE() for
pci_segments and ivrs_maps.

This then fixes an ordering issue on x86: With the call to
radix_tree_init(), acpi_mmcfg_init()'s invocation of pci_segments_init()
will zap the possible earlier introduction of segment 0 by
amd_iommu_detect_one_acpi()'s call to pci_ro_device(), and thus the
write-protection of the PCI devices representing AMD IOMMUs.

Fixes: 3950f2485b ("x86/x2APIC: defer probe until after IOMMU ACPI table parsing")
Requested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 26fe09e345
master date: 2025-02-07 10:00:04 +0100
2025-02-17 13:23:00 +01:00
Jan Beulich ebc8b4a450 radix-tree: purge node allocation override hooks
These were needed by TMEM only, which is long gone. The Linux original
doesn't have such either. This effectively reverts one of the "Other
changes" from 8dc6738dbb ("Update radix-tree.[ch] from upstream Linux
to gain RCU awareness").

Positive side effect: Two cf_check go away.

While there also convert xmalloc()+memset() to xzalloc().

Requested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 1275093a96
master date: 2025-02-07 09:59:11 +0100
2025-02-17 13:22:24 +01:00
Jan Beulich 125270d49d x86/PV: further harden guest memory accesses against speculative abuse
The original implementation has two issues: For one it doesn't preserve
non-canonical-ness of inputs in the range 0x8000000000000000 through
0x80007fffffffffff. Bogus guest pointers in that range would not cause a
(#GP) fault upon access, when they should.

And then there is an AMD-specific aspect, where only the low 48 bits of
an address are used for speculative execution; the architecturally
mandated #GP for non-canonical addresses would be raised at a later
execution stage. Therefore to prevent Xen controlled data to make it
into any of the caches in a guest controllable manner, we need to
additionally ensure that for non-canonical inputs bit 47 would be clear.

See the code comment for how addressing both is being achieved.

Fixes: 4dc1815991 ("x86/PV: harden guest memory accesses against speculative abuse")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
master commit: 8306d773b0
master date: 2025-01-27 15:23:59 +0100
2025-02-17 13:21:30 +01:00
Jan Beulich b7b0ce5e11 x86emul: further correct 64-bit mode zero count repeated string insn handling
In an entirely different context I came across Linux commit 428e3d08574b
("KVM: x86: Fix zero iterations REP-string"), which points out that
we're still doing things wrong: For one, there's no zero-extension at
all on AMD. And then while RCX is zero-extended from 32 bits uniformly
for all string instructions on newer hardware, RSI/RDI are only for MOVS
and STOS on the systems I have access to. (On an old family 0xf system
I've further found that for REP LODS even RCX is not zero-extended.)

While touching the lines anyway, replace two casts in get_rep_prefix().

Fixes: 79e996a89f ("x86emul: correct 64-bit mode repeated string insn handling with zero count")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
master commit: 5310a042c4
master date: 2025-01-27 15:23:19 +0100
2025-02-17 13:21:00 +01:00
Jan Beulich e990bf3de5 x86/HVM: correct read/write split at page boundaries
The MMIO cache is intended to have one entry used per independent memory
access that an insn does. This, in particular, is supposed to be
ignoring any page boundary crossing. Therefore when looking up a cache
entry, the access'es starting (linear) address is relevant, not the one
possibly advanced past a page boundary.

In order for the same offset-into-buffer variable to be usable in
hvmemul_phys_mmio_access() for both the caller's buffer and the cache
entry's it is further necessary to have the un-adjusted caller buffer
passed into there.

Fixes: 2d527ba310 ("x86/hvm: split all linear reads and writes at page boundary")
Reported-by: Manuel Andreas <manuel.andreas@tum.de>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
master commit: 672894a11f
master date: 2025-01-24 10:15:56 +0100
2025-02-17 13:19:51 +01:00
Jan Beulich dcac022fd9 x86/HVM: allocate emulation cache entries dynamically
Both caches may need higher capacity, and the upper bound will need to
be determined dynamically based on CPUID policy (for AMX'es TILELOAD /
TILESTORE at least).

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
master commit: 23d60dbb04
master date: 2025-01-24 10:15:29 +0100
2025-02-17 13:19:04 +01:00
Jan Beulich 15f83e2744 x86/HVM: correct MMIO emulation cache bounds check
To avoid overrunning the internal buffer we need to take the offset into
the buffer into account.

Fixes: d95da91fb4 ("x86/HVM: grow MMIO cache data size to 64 bytes")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
master commit: e5339bb689
master date: 2025-01-23 11:14:48 +0100
2025-02-17 13:18:15 +01:00
Jan Beulich 41d38d270e x86/HVM: reduce recursion in linear_{read,write}()
Let's make explicit what the compiler may or may not do on our behalf:
The 2nd of the recursive invocations each can fall through rather than
re-invoking the function. This will save us from adding yet another
parameter (or more) to the function, just for the recursive invocations.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 18053054b7
master date: 2024-09-09 13:40:47 +0200
2025-02-17 13:17:45 +01:00
Jan Beulich 4df28706ad x86emul: correct put_fpu()'s segment selector handling
All selector fields under ctxt->regs are (normally) poisoned in the HVM
case, and the four ones besides CS and SS are potentially stale for PV.
Avoid using them in the hypervisor incarnation of the emulator, when
trying to cover for a missing ->read_segment() hook.

To make sure there's always a valid ->read_segment() handler for all HVM
cases, add a respective function to shadow code, even if it is not
expected for FPU insns to be used to update page tables.

Fixes: 0711b59b85 ("x86emul: correct FPU code/data pointers and opcode handling")
Reported-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 645b8d48c7
master date: 2025-01-08 11:02:16 +0100
2025-01-21 09:19:56 +01:00
Jan Beulich 4abf7f1d61 x86emul: VCVT{,U}DQ2PD ignores embedded rounding
IOW we shouldn't raise #UD in that case. Be on the safe side though and
only encode fully legitimate forms into the stub to be executed.

Things weren't quite right for VCVT{,U}SI2SD either, in the attempt to
be on the safe side: Clearing EVEX.L'L isn't useful; it's EVEX.b which
primarily needs clearing. Also reflect the somewhat improved doc
situation in the comment there.

Fixes: ed806f3737 ("x86emul: support AVX512F legacy-equivalent packed int/FP conversion insns")
Fixes: baf4a376f5 ("x86emul: support AVX512F legacy-equivalent scalar int/FP conversion insns")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: d3709d1324
master date: 2025-01-08 11:01:17 +0100
2025-01-21 09:19:39 +01:00
Jan Beulich 3a9e5a93e6 x86emul: MOVBE requires a memory operand
The reg-reg forms should cause #UD; they come into existence only with
APX, where MOVBE also extends BSWAP (for the latter not being "eligible"
to a REX2 prefix).

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 4c5d9a01f8
master date: 2024-12-02 09:50:14 +0100
2024-12-16 13:32:19 +01:00
Jan Beulich 5d61bc0585 update Xen version to 4.19.2-pre 2024-12-16 13:31:51 +01:00
Jan Beulich ccf4008467 update Xen version to 4.19.1 2024-12-04 08:52:37 +01:00
Jan Beulich e461f0cd14 x86emul: avoid double memory read for RORX
Originally only twobyte_table[0x3a] determined what part of generic
operand fetching (near the top of x86_emulate()) comes into play. When
ext0f3a_table[] was added, ->desc was updated to properly describe the
ModR/M byte's function. With that generic source operand fetching came
into play for RORX, rendering the explicit fetching in the respective
case block redundant (and wrong at the very least when MMIO with side
effects is accessed).

While there also make a purely cosmetic / documentary adjustment to
ext0f3a_table[]: RORX really is a 2-operand insn, MOV-like in that it
only writes its destination register.

Fixes: 9f7f5f6bc9 ("x86emul: add tables for 0f38 and 0f3a extension space")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 939a9e800c
master date: 2024-11-14 13:03:18 +0100
2024-11-25 12:01:50 +01:00
Jan Beulich 7da6997e46 x86emul: ignore VEX.W for BMI{1,2} insns in 32-bit mode
While result values and other status flags are unaffected as long as we
can ignore the case of registers having their upper 32 bits non-zero
outside of 64-bit mode, EFLAGS.SF may obtain a wrong value when we
mistakenly re-execute the original insn with VEX.W set.

Note that guest the memory access, if any, is correctly carried out as
32-bit regardless of VEX.W. The emulator-local memory operand will be
accessed as a 64-bit quantity, but it is pre-initialised to zero so no
internal state can leak.

Fixes: 771daacd19 ("x86emul: support BMI1 insns")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 1179d51dcb
master date: 2024-11-14 13:00:57 +0100
2024-11-25 12:01:20 +01:00
Jan Beulich 1cb4e0a5fe x86/HVM: drop stdvga's "lock" struct member
No state is left to protect. It being the last field, drop the struct
itself as well. Similarly for then ending up empty, drop the .complete
handler.

This is part of XSA-463 / CVE-2024-45818

Suggested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
(cherry picked from commit b180a50326)
2024-11-12 13:40:33 +01:00
Jan Beulich 7b2df91a0e x86/HVM: drop stdvga's "vram_page[]" struct member
No uses are left, hence its setup, teardown, and the field itself can
also go away. stdvga_deinit() is then empty and can be dropped as well.

This is part of XSA-463 / CVE-2024-45818

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
(cherry picked from commit 3beb4baf2a)
2024-11-12 13:40:15 +01:00
Jan Beulich 77cb6587d4 x86/HVM: drop stdvga's "{g,s}r_index" struct members
No consumers are left, hence the producer and the fields themselves can
also go away. stdvga_outb() is then useless, rendering stdvga_out()
useless as well. Hence the entire I/O port intercept can go away.

This is part of XSA-463 / CVE-2024-45818

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
(cherry picked from commit 86c03372e1)
2024-11-12 13:39:56 +01:00
Jan Beulich 04f1c5e6f7 x86/HVM: drop stdvga's "sr[]" struct member
No consumers are left, hence the producer and the array itself can also
go away. The static sr_mask[] is then orphaned and hence needs dropping,
too.

This is part of XSA-463 / CVE-2024-45818

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
(cherry picked from commit 7aba44bdd7)
2024-11-12 13:39:38 +01:00
Jan Beulich 2334fb4fef x86/HVM: drop stdvga's "gr[]" struct member
No consumers are left, hence the producer and the array itself can also
go away. The static gr_mask[] is then orphaned and hence needs dropping,
too.

This is part of XSA-463 / CVE-2024-45818

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
(cherry picked from commit b16c0966a1)
2024-11-12 13:39:19 +01:00
Jan Beulich 2ac4917c24 x86/HVM: remove unused MMIO handling code
All read accesses are rejected by the ->accept handler, while writes
bypass the bulk of the function body. Drop the dead code, leaving an
assertion in the read handler.

A number of other static items (and a macro) are then unreferenced and
hence also need (want) dropping. The same applies to the "latch" field
of the state structure.

This is part of XSA-463 / CVE-2024-45818

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
(cherry picked from commit 89108547af)
2024-11-12 13:38:59 +01:00
Jan Beulich 92667bef14 x86/HVM: drop stdvga's "stdvga" struct member
Two of its consumers are dead (in compile-time constant conditionals)
and the only remaining ones are merely controlling debug logging. Hence
the field is now pointless to set, which in particular allows to get rid
of the questionable conditional from which the field's value was
established (afaict 551ceee975 ["x86, hvm: stdvga cache always on"]
had dropped too much of the earlier extra check that was there, and
quite likely further checks were missing).

This is part of XSA-463 / CVE-2024-45818

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
(cherry picked from commit b740a9369e)
2024-11-12 13:38:35 +01:00
Jan Beulich ed8105c364 x86/HVM: drop stdvga's "cache" struct member
Since 68e1183411 ("libxc: introduce a xc_dom_arch for hvm-3.0-x86_32
guests"), HVM guests are built using XEN_DOMCTL_sethvmcontext, which
ends up disabling stdvga caching because of arch_hvm_load() being
involved in the processing of the request. With that the field is
useless, and can be dropped. Drop the helper functions manipulating /
checking as well right away, but leave the use sites of
stdvga_cache_is_enabled() with the hard-coded result the function would
have produced, to aid validation of subsequent dropping of further code.

This is part of XSA-463 / CVE-2024-45818

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
(cherry picked from commit 53b7246bdf)
2024-11-12 13:38:08 +01:00
Jan Beulich d15e9fa3c8 ioreq: don't wrongly claim "success" in ioreq_send_buffered()
Returning a literal number is a bad idea anyway when all other returns
use IOREQ_STATUS_* values. The function is dead on Arm, and mapping to
X86EMUL_OKAY is surely wrong on x86.

Fixes: f6bf39f84f ("x86/hvm: add support for broadcast of buffered ioreqs...")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
master commit: 2e0b545b84
master date: 2024-10-08 14:36:27 +0200
2024-10-29 16:29:47 +01:00
Jan Beulich 950e57e0ce x86/PV: simplify (and thus correct) guest accessor functions
Taking a fault on a non-byte-granular insn means that the "number of
bytes not handled" return value would need extra care in calculating, if
we want callers to be able to derive e.g. exception context (to be
injected to the guest) - CR2 for #PF in particular - from the value. To
simplify things rather than complicating them, reduce inline assembly to
just byte-granular string insns. On recent CPUs that's also supposed to
be more efficient anyway.

For singular element accessors, however, alignment checks are added,
hence slightly complicating the code. Misaligned (user) buffer accesses
will now be forwarded to copy_{from,to}_guest_ll().

Naturally copy_{from,to}_unsafe_ll() accessors end up being adjusted the
same way, as they're produced by mere re-processing of the same code.
Otoh copy_{from,to}_unsafe() aren't similarly adjusted, but have their
comments made match reality; down the road we may want to change their
return types, e.g. to bool.

Fixes: 76974398a6 ("Added user-memory accessing functionality for x86_64")
Fixes: 7b8c36701d ("Introduce clear_user and clear_guest")
Reported-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Tested-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 67a8e5721e
master date: 2024-10-01 09:44:55 +0200
2024-10-29 16:26:30 +01:00
Jan Beulich ec3999e205 x86/HVM: properly reject "indirect" VRAM writes
While ->count will only be different from 1 for "indirect" (data in
guest memory) accesses, it being 1 does not exclude the request being an
"indirect" one. Check both to be on the safe side, and bring the ->count
part also in line with what ioreq_send_buffered() actually refuses to
handle.

Fixes: 3bbaaec09b ("x86/hvm: unify stdvga mmio intercept with standard mmio intercept")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: eb7cd0593d
master date: 2024-09-12 09:13:04 +0200
2024-09-24 14:43:02 +02:00
Jan Beulich 78d412f8bc x86emul/test: fix build with gas 2.43
Drop explicit {evex} pseudo-prefixes. New gas (validly) complains when
they're used on things other than instructions. Our use was potentially
ahead of macro invocations - see simd.h's "override" macro.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 3c09288298
master date: 2024-09-06 08:41:18 +0200
2024-09-24 14:42:39 +02:00
Jan Beulich d625c4e9fb x86: fix UP build with gcc14
The complaint is:

In file included from ././include/xen/config.h:17,
                 from <command-line>:
arch/x86/smpboot.c: In function ‘link_thread_siblings.constprop’:
./include/asm-generic/percpu.h:16:51: error: array subscript [0, 0] is outside array bounds of ‘long unsigned int[1]’ [-Werror=array-bounds=]
   16 |     (*RELOC_HIDE(&per_cpu__##var, __per_cpu_offset[cpu]))
./include/xen/compiler.h:140:29: note: in definition of macro ‘RELOC_HIDE’
  140 |     (typeof(ptr)) (__ptr + (off)); })
      |                             ^~~
arch/x86/smpboot.c:238:27: note: in expansion of macro ‘per_cpu’
  238 |     cpumask_set_cpu(cpu2, per_cpu(cpu_sibling_mask, cpu1));
      |                           ^~~~~~~
In file included from ./arch/x86/include/generated/asm/percpu.h:1,
                 from ./include/xen/percpu.h:30,
                 from ./arch/x86/include/asm/cpuid.h:9,
                 from ./arch/x86/include/asm/cpufeature.h:11,
                 from ./arch/x86/include/asm/system.h:6,
                 from ./include/xen/list.h:11,
                 from ./include/xen/mm.h:68,
                 from arch/x86/smpboot.c:12:
./include/asm-generic/percpu.h:12:22: note: while referencing ‘__per_cpu_offset’
   12 | extern unsigned long __per_cpu_offset[NR_CPUS];
      |                      ^~~~~~~~~~~~~~~~

Which I consider bogus in the first place ("array subscript [0, 0]" vs a
1-element array). Yet taking the experience from 99f942f3d4 ("Arm64:
adjust __irq_to_desc() to fix build with gcc14") I guessed that
switching function parameters to unsigned int (which they should have
been anyway) might help. And voilà ...

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: a2de7dc4d8
master date: 2024-09-04 16:09:28 +0200
2024-09-24 14:41:59 +02:00
Jan Beulich 3ceb79ceab SUPPORT.md: split XSM from Flask
XSM is a generic framework, which in particular is also used by SILO.
With this it can't really be experimental: Arm mandates SILO for having
a security supported configuration.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Daniel P. Smith <dpsmith@apertussolutions.com>
master commit: d7c18b8720
master date: 2024-09-04 16:05:03 +0200
2024-09-24 14:41:51 +02:00
Jan Beulich ee826bc490 Arm64: adjust __irq_to_desc() to fix build with gcc14
With the original code I observe

In function ‘__irq_to_desc’,
    inlined from ‘route_irq_to_guest’ at arch/arm/irq.c:465:12:
arch/arm/irq.c:54:16: error: array subscript -2 is below array bounds of ‘irq_desc_t[32]’ {aka ‘struct irq_desc[32]’} [-Werror=array-bounds=]
   54 |         return &this_cpu(local_irq_desc)[irq];
      |                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

which looks pretty bogus: How in the world does the compiler arrive at
-2 when compiling route_irq_to_guest()? Yet independent of that the
function's parameter wants to be of unsigned type anyway, as shown by
a vast majority of callers (others use plain int when they really mean
non-negative quantities). With that adjustment the code compiles fine
again.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Michal Orzel <michal.orzel@amd.com>
master commit: 99f942f3d4
master date: 2024-08-29 10:03:53 +0200
2024-09-24 14:40:34 +02:00
Jan Beulich 6e96dee93c x86/HVM: correct partial HPET_STATUS write emulation
For partial writes the non-written parts of registers are folded into
the full 64-bit value from what they're presently set to. That's wrong
to do though when the behavior is write-1-to-clear: Writes not
including to low 3 bits would unconditionally clear all ISR bits which
are presently set. Re-calculate the value to use.

Fixes: be07023be1 ("x86/vhpet: add support for level triggered interrupts")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 41d358d2f9
master date: 2024-08-29 10:02:20 +0200
2024-09-24 14:40:03 +02:00
Jan Beulich 404fb9b745 x86/x2APIC: correct cluster tracking upon CPUs going down for S3
Downing CPUs for S3 is somewhat special: Since we can expect the system
to come back up in exactly the same hardware configuration, per-CPU data
for the secondary CPUs isn't de-allocated (and then cleared upon re-
allocation when the CPUs are being brought back up). Therefore the
cluster_cpus per-CPU pointer will retain its value for all CPUs other
than the final one in a cluster (i.e. in particular for all CPUs in the
same cluster as CPU0). That, however, is in conflict with the assertion
early in init_apic_ldr_x2apic_cluster().

Note that the issue is avoided on Intel hardware, where we park CPUs
instead of bringing them down.

Extend the bypassing of the freeing to the suspend case, thus making
suspend/resume also a tiny bit faster.

Fixes: 2e6c8f182c ("x86: distinguish CPU offlining from CPU removal")
Reported-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Tested-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: ad3ff7b427
master date: 2024-08-26 10:30:40 +0200
2024-09-24 14:38:27 +02:00
Jan Beulich a0d6b75b83 x86emul: set (fake) operand size for AVX512CD broadcast insns
Back at the time I failed to pay attention to op_bytes still being zero
when reaching the respective case block: With the ext0f38_table[]
entries having simd_packed_int, the defaulting at the bottom of
x86emul_decode() won't set the field to non-zero for F3-prefixed insns.

Fixes: 37ccca740c ("x86emul: support AVX512CD insns")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 6fa6b7feaa
master date: 2024-08-23 09:12:24 +0200
2024-09-24 14:37:52 +02:00
Jan Beulich 1e68200487 x86emul: always set operand size for AVX-VNNI-INT8 insns
Unlike for AVX-VNNI-INT16 I failed to notice that op_bytes may still be
zero when reaching the respective case block: With the ext0f38_table[]
entries having simd_packed_int, the defaulting at the bottom of
x86emul_decode() won't set the field to non-zero for F3- or F2-prefixed
insns.

Fixes: 842acaa743 ("x86emul: support AVX-VNNI-INT8")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: d45687cca2
master date: 2024-08-23 09:11:15 +0200
2024-09-24 14:37:08 +02:00
Jan Beulich e2f29f7bad x86emul: correct #UD check for AVX512-FP16 complex multiplications
avx512_vlen_check()'s argument was inverted, while the surrounding
conditional wrongly forced the EVEX.L'L check for the scalar forms when
embedded rounding was in effect.

Fixes: d14c52cba0 ("x86emul: handle AVX512-FP16 complex multiplication insns")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: a30d438ce5
master date: 2024-08-19 15:32:31 +0200
2024-09-24 14:30:04 +02:00
Jan Beulich 46a2ce3521 Arm: correct FIXADDR_TOP
While reviewing a RISC-V patch cloning the Arm code, I noticed an
off-by-1 here: FIX_PMAP_{BEGIN,END} being an inclusive range and
FIX_LAST being the same as FIX_PMAP_END, FIXADDR_TOP cannot derive from
FIX_LAST alone, or else the BUG_ON() in virt_to_fix() would trigger if
FIX_PMAP_END ended up being used.

While touching this area also add a check for fixmap and boot FDT area
to not only not overlap, but to have at least one (unmapped) page in
between.

Fixes: 4f17357b52 ("xen/arm: add Persistent Map (PMAP) infrastructure")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Michal Orzel <michal.orzel@amd.com>
master commit: fe3412ab83
master date: 2024-08-13 21:50:55 +0100
2024-09-24 14:28:22 +02:00
Jan Beulich 9358a7fad7 x86/vLAPIC: prevent undue recursion of vlapic_error()
With the error vector set to an illegal value, the function invoking
vlapic_set_irq() would bring execution back here, with the non-recursive
lock already held. Avoid the call in this case, merely further updating
ESR (if necessary).

This is XSA-462 / CVE-2024-45817.

Fixes: 5f32d186a8 ("x86/vlapic: don't silently accept bad vectors")
Reported-by: Federico Serafini <federico.serafini@bugseng.com>
Reported-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: c42d9ec61f
master date: 2024-09-24 14:23:29 +0200
2024-09-24 14:27:03 +02:00
Jan Beulich 3e8a2217f2 x86/pass-through: documents as security-unsupported when sharing resources
When multiple devices share resources and one of them is to be passed
through to a guest, security of the entire system and of respective
guests individually cannot really be guaranteed without knowing
internals of any of the involved guests.  Therefore such a configuration
cannot really be security-supported, yet making that explicit was so far
missing.

This is XSA-461 / CVE-2024-31146.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
master commit: 9c94eda1e3
master date: 2024-08-13 16:37:25 +0200
2024-08-13 16:48:13 +02:00
Jan Beulich 8ad5a8c5c3 9pfsd: fix release build with old gcc
Being able to recognize that "par" is reliably initialized on the 1st
loop iteration requires not overly old compilers.

Fixes: 7809132b1a ("tools/xen-9pfsd: add 9pfs response generation support")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
master commit: 984cb316cb
master date: 2024-08-02 08:44:22 +0200
2024-08-08 13:47:44 +02:00