Commit Graph
100 Commits
Author SHA1 Message Date
Jan Beulich a5c41f94d9 x86/mm: get_page_from_l1e() is PV-or-shadow-only
Otherwise the function is unreachable, violating MISRA C:2012 rule 2.1.
With the function compiled out, its dedicated XSM hook also becomes
unreachable, so it is similarly guarded.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Daniel P. Smith <dpsmith@apertussolutions.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2026-09-23 10:00:43 +02:00
Jan Beulich 8d70af242d x86/HVM: replace paging_mode_hap() uses
HVM guests cannot run without either HAP or shadow enabled. While
paging_mode_shadow() is compile-time-constant when SHADOW_PAGING=n,
paging_mode_hap() isn't. Hence the former is preferred to leverage DCE.

In svm_update_guest_cr() combine two adjacent conditionals.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Alejandro Vallejo <alejandro.garciavallejo@amd.com>
Acked-by: Roger Pau Monné <roger@xenproject.org>
2026-09-22 09:59:48 +02:00
Jan Beulich 06438aead6 build: move $(compare-symbol-tables)
With the final linking logic now consolidated in scripts/Makefile.link,
$(compare-symbol-tables) also doesn't need setting anymore in
Kbuild.include.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
2026-09-22 09:59:28 +02:00
Jan Beulich 0a609dc49a build: move $(all-symbols-*)
With the final linking logic now consolidated in scripts/Makefile.link,
$(all-symbols-*) also doesn't need setting anymore in (and passing down
from) the top level Makefile.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
2026-09-22 09:59:24 +02:00
Jan Beulich 37cd2d7d46 RISC-V: split xen-syms linking rule
Doing so, besides (hopefully) adding clarity (not the least by way of
[re-]using pattern rules where possible), also avoids explicit recursive
$(MAKE) invocations.

By re-using the generic rules introduced when the respective x86 rule was
split,
- the .map file now isn't created after the final binary anymore,
- --strip-debug is passed to $(LD) during early linking passes (for
  consistency the option is also explicitly added to the optional linking
  pass rule),
- CONFIG_{SUPPRESS_DUPLICATE_SYMBOL_WARNINGS,ENFORCE_UNIQUE_SYMBOLS} are
  now properly respected.
Orphan section checking, otoh, is getting suppressed for now, until the
about a dozen warnings which would result have been taken care of.

While the 4th linking step continues to be avoided when possible, a
redundant invocation of $(NM) and tools/symbols (plus the assembling of
the resulting .S file) is hopefully deemed acceptable.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
2026-09-22 09:59:17 +02:00
Jan Beulich 223ac5068a Arm: split xen-syms linking rule
Doing so, besides (hopefully) adding clarity (not the least by way of
[re-]using pattern rules where possible), also avoids explicit recursive
$(MAKE) invocations.

By re-using the generic rules introduced when the respective x86 rule was
split,
- the .map file now isn't created after the final binary anymore,
- --strip-debug is passed to $(LD) during early linking passes (for
  consistency the option is also explicitly added to the optional linking
  pass rule),
- CONFIG_{SUPPRESS_DUPLICATE_SYMBOL_WARNINGS,ENFORCE_UNIQUE_SYMBOLS} are
  now properly respected.
Orphan section checking and erroring on duplicate symbols, otoh, are
getting suppressed for now, until the about a dozen orphan section
warnings and the one duplicate symbol error which would result have been
taken care of.

While the 4th linking step continues to be avoided when possible, a
redundant invocation of $(NM) and tools/symbols (plus the assembling of
the resulting .S file) is hopefully deemed acceptable.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
Acked-by: Michal Orzel <michal.orzel@amd.com>
2026-09-22 09:59:00 +02:00
Jan Beulich 5b063007d5 automation/Eclair: tag rule 13.1 as clean
Remaining violations were addressed.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Nicola Vetrini <nicola.vetrini@bugseng.com>
2026-09-22 09:17:04 +02:00
Jan Beulich 7963131d64 Arm/guestcopy: avoid use of "current" in compound literals
Compound literals are also covered by Misra C:2012 rule 13.1
("Initializer lists shall not contain persistent side effects"), and
(sadly?) that rule also applies to lists with just a single element, or
more generally with just a single side effect. Use intermediate variables
to overcome this.

No functional change intended.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Michal Orzel <michal.orzel@amd.com>
2026-09-22 09:15:48 +02:00
Jan Beulich 578ac3ee3e x86/pagewalk: avoid ACCESS_ONCE() in compound literals
Compound literals are also covered by Misra C:2012 rule 13.1
("Initializer lists shall not contain persistent side effects"), and
(sadly?) that rule also applies to lists with just a single element, or
more generally with just a single side effect. Use intermediate variables
to overcome this as well as ACCESS_ONCE()'s restriction to be usable on
scalar types only.

No functional change intended.

Fixes: 0345b835dc ("x86/pagewalk: Read guest PTEs with ACCESS_ONCE()")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger@xenproject.org>
2026-09-22 09:15:05 +02:00
Jan Beulich 25055cde91 crypto/vmac: don't cast away const-ness in aes_key_setup()
vmac_set_key() passes in a pointer-to-const, which has const-ness removed
despite rijndaelKeySetupEnc() properly taking pointer-to-const.

No functional change.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Volodymyr Babchuk <volodymyr_babchuk@epam.com>
2026-09-22 09:13:47 +02:00
Jan Beulich 40ad6282e2 Arm/guestcopy: deviate copy_guest() uses just like their x86 counterparts
Like x86/HVM's __hvm_copy(), Arm's copy_guest() is used for both to-guest
and from-guest copying. Naturally in the latter case the hypervisor buffer
needs writing to, hence the function parameter cannot be pointer-to-const.

No functional change intended.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Michal Orzel <michal.orzel@amd.com>
Reviewed-by: Nicola Vetrini <nicola.vetrini@bugseng.com>
2026-09-22 09:13:19 +02:00
Jan Beulich d4d8d3bfba lib: obey to Misra rule 11.8 where possible
Casting away const-ness (or volatile-ness) is never a good idea, but
some library functions (e.g. strchr()) require doing so. Where not
required, remove / replace respective casts.

While there convert touched functions to Xen style.

No functional change intended.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Volodymyr Babchuk <volodymyr_babchuk@epam.com>
2026-09-22 09:12:33 +02:00
Jan Beulich a401b5c9dc Eclair: re-enable scanning of the (almost) final linking step
The real final binaries are now no longer created by a linker invocation,
but by renaming an intermediate file (each). Arrange for linking pass 2
outputs to be scanned instead, yet continue to exclude the auxiliary
.xen.efi.alt.* binaries.

Fixes: da944a72fd ("x86: split xen-syms/xen.efi linking rules"))
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Nicola Vetrini <nicola.vetrini@bugseng.com>
2026-09-21 10:09:45 +02:00
Jan Beulich 68c3f7fb3a Eclair: relax long <-> function-pointer conversion deviation
What is true for unsigned long is also true for plain/signed long, thus
also taking care of two instances of __x86_return_thunk() being cast to
long.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Nicola Vetrini <nicola.vetrini@bugseng.com>
2026-09-21 09:59:08 +02:00
Jan Beulich 9fd71d2257 x86/domain: address Misra rule 11.1 violation in reset_stack_and_call_ind()
Eclair dislikes both sides of the comparison to differ in noreturn
attributes, thus deeming this a violation of "Conversions shall not be
performed between a pointer to a function and any other type". Since gcc
doesn't permit use of "noreturn" types used in a typecast, resort to
typeof().

No functional change intended.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Nicola Vetrini <nicola.vetrini@bugseng.com>
2026-09-21 09:58:31 +02:00
Jan Beulich b0597289eb x86: always park offline CPUs
While on AMD (or Hygon) CPUs the situation isn't as bad wrt broadcasting
of #MC, some "multicast" can still happen. Therefore the reasoning to park
CPUs rather than fully offlining them applies everywhere.

Don't retain the dependency on the "mce=" cmdline option either: That
option may best be dropped as well, as not enabling MCE will result in a
shutdown when #MC would otherwise be raised.

Drop the global variable, using a #define (just like common code does)
instead. Outside of common code, simplify expressions / code accordingly.
(In common code we still have to cater for x86 wanting it different from
everyone else.)

Suggested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2026-09-21 09:57:22 +02:00
Jan Beulich acd87f99ac sched/core: avoid use of "current" in initializer lists
TRACE_TIME() uses an initializer list and hence is covered by Misra C:2012
rule 13.1 ("Initializer lists shall not contain persistent side effects").
Use intermediate variables to address this.

In vcpu_yield() take the opportunity to rename the existing variable which
better would have been used already before.

In do_sched_op() extend the scope of and rename an existing variable. Also
drop a pointless (and slightly malformed, style-wise) cast there, and
adjust to other one to by style conformant.

No functional change intended.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
2026-09-11 08:55:16 +02:00
Jan Beulich 0c8460766a x86/nSVM: address Misra 2.1 rule violation
The 16-bit range of "port" is fully handled by the switch(). Therefore the
default: case is reported unreachable by Eclair. Insert BUILD_ERROR() to
annotate this for Eclair.

No functional change.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger@xenproject.org>
2026-09-11 08:54:53 +02:00
Jan Beulich bc24cc6b72 x86/HVM: address Misra 2.1 rule violations
In hvm_set_cr3() the "bad_cr3" label is reachable only with
SHADOW_PAGING=y; the code being there is therefore a Misra rule 2.1
(unreachable code) violation when SHADOW_PAGING=n.

Similarly code past the initial switch() in hvm_debug_op() is reachable
only when CONFIG_INTEL_VMX=y.

No functional change.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger@xenproject.org>
2026-09-11 08:53:58 +02:00
Jan Beulich 7fc89f9649 x86/shadow: eliminate unused forms of sh_map_and_validate_gl<N>e()
The L2H, L3, and L4 forms only have GUEST_PAGING_LEVELS=4 call sites, i.e.
their 2- and 3-level forms are unreachable, violating Misra rule 2.1. The
L2H form additionally is unused (call site DCE-d) with PV32=n.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger@xenproject.org>
2026-09-11 08:53:19 +02:00
Jan Beulich 4fcd42a958 x86/mm: pagetable_dying() is HVM+SHADOW_PAGING only
The referenced commit didn't go far enough, leaving a Misra rule 2.1
(unreachable code) violation: The function lacks "noreturn" in this
configuration. Since with SHADOW_PAGING=n paging_mode_shadow() is compile-
time-constant false, the compiler can DCE the call site. Hence we can
avoid building the function itself altogether.

No functional change.

Fixes: 2fb2dee1ac ("x86/mm: pagetable_dying() is HVM-only")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger@xenproject.org>
2026-09-11 08:52:40 +02:00
Jan Beulich 04d4312440 x86/EFI: adjust efi_multiboot2_prelude() to comply to Misra rule 18.2
While casting to pointer types may be more natural there, the subtraction
then ends up violating "Subtraction between pointers shall only be applied
to pointers that address elements of the same array". Use unsigned long
arithmetic instead.

No functional change intended.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
2026-09-10 09:01:30 +02:00
Jan Beulich c3b570e1b5 x86/PCI: use pci_sbdf_t also for pci_dev_base()
No need to pass three arguments when both callers already hold SBDF in
their hands.

No functional change.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger@xenproject.org>
Reviewed-by: Teddy Astie <teddy.astie@vates.tech>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2026-09-10 09:00:55 +02:00
Jan Beulich 1b12a20631 PPC: split xen-syms linking rule
Doing so, besides (hopefully) adding clarity (not the least by way of
[re-]using pattern rules where possible), also avoids explicit recursive
$(MAKE) invocations.

By re-using the generic rules introduced when the respective x86 rule was
split,
- the .map file now isn't created after the final binary anymore,
- --strip-debug is passed to $(LD) during early linking passes (for
  consistency the option is also explicitly added to the optional linking
  pass rule),
- CONFIG_{SUPPRESS_DUPLICATE_SYMBOL_WARNINGS,ENFORCE_UNIQUE_SYMBOLS} are
  now properly respected.
Orphan section checking, otoh, is getting suppressed for now, until the
about a dozen warnings which would result have been taken care of.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
2026-09-10 09:00:16 +02:00
Jan Beulich da944a72fd x86: split xen-syms/xen.efi linking rules
Doing so, besides (hopefully) adding clarity (not the least by way of
using pattern rules where possible), also avoids explicit recursive
$(MAKE) invocations. For xen-syms move re-usable helper rules to a new
scripts/Makefile.link.

While doing so, re-order .map file creation (which can in principle fail)
and check-endbr.sh invocation ahead of putting in place the final image
(which is now the result of a simple rename).

Also drop --source-name= from the tools/symbols invocation which has
--empty passed, for being meaningless there.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
2026-09-10 08:59:50 +02:00
Jan Beulich cd68e5bc02 x86/HVM: move evtchn_upcall_vector field
... into an available 8-bit slot, rather than having it followed by 7
bytes of padding.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2026-09-09 14:15:43 +02:00
Jan Beulich 5df9425a73 EFI: don't use alias attribute for compat hypercall stubs
Recent Clang objects to types differing between alias and aliasee. Accept
the unnecessary overhead and make the two compat stubs real functions.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
2026-09-09 14:15:15 +02:00
Jan Beulich 328a146143 x86/pass-through: disallow pt_irq_create_bind() on dying domains
DMs may invoke XEN_DOMCTL_bind_pt_irq for domains already under
destruction. When XEN_DOMCTL_bind_pt_irq is invoked after
pci_release_devices() (invoked from underneath domain_kill()) had already
completed, it would allocate hvm_domain_irq(d)->dpci anew, without that
ever being freed during subsequent domain cleanup.

Leverage evtchn_destroy()'s kind-of-spin-barrier, allowing to simply check
->is_dying with the domain's event lock held.

This is XSA-509 / CVE-2026-62437.

Fixes: 7a26b541a2 ("vtd: Dynamically allocate IRQ-tracking structures, only for those")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
2026-09-08 12:57:23 +01:00
Jan Beulich f7eab298bb build: also exclude .data.rel.ro in $(cmd_obj_init_o)
.data.rel.ro really is merely a special case of .rodata: r/o data, but
with runtime relocations (not relevant to Xen), i.e. r/o only after
relocations were performed (by the dynamic loader).

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2026-09-08 09:50:48 +02:00
Jan Beulich f907784c32 libacpi: drop mk_dsdt's -d / --debug option
Recent Clang complains about the "debug" static variable only ever being
written to. Drop it and the command line option controlling it.

Fixes: 19ab8356ab ("tools: remove support for running a guest with qemu-traditional")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Roger Pau Monné <roger@xenproject.org>
2026-09-07 14:11:35 +02:00
Jan Beulich 44a6486a4f x86/vRTC: don't overrun array when storing century field
rtc_ioport_write() has two writes of the new value, yet only one was made
aware of the century going outside of the array. Fold both writes by
changing the RTC_SET short-circuiting.

Fixes: f2ff80877f ("x86/vRTC: support century field")
Coverity ID: 1700943
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger@xenproject.org>
2026-09-07 14:11:18 +02:00
Jan Beulich 582b94e41b x86emul: adjust file comments
With the split-off of decoding into a separate file, both files' top
comments should have been adjusted accordingly.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2026-09-07 10:41:27 +02:00
Jan Beulich 74b0008044 x86/altcall: hide casting away of const
ALT_CALL_PTR() really means to get rid of const (when necessary, i.e. when
used from apply_alt_calls()): We want to patch the original call site,
after all, and memory-wise that's unrelated to the struct alt_call * that
we start from.

No functional change intended.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger@xenproject.org>
2026-09-07 10:41:04 +02:00
Jan Beulich 1e204d768b x86/boot: don't cast away const-ness
While the general C library strchr() has to do so, the early boot cmdline
parsing has no such requirement.

No functional change.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger@xenproject.org>
2026-09-07 10:40:50 +02:00
Jan Beulich 48728c33e4 x86/alternatives: mark .altinstructions r/w
Forever since the introduction of the .priv member it has been wrong to
record the section as r/o.

.alt_call_sites, otoh, is legitimately r/o, hence
__alt_call_sites_{start,end}[] would better reflect that.

Fixes: 4008c71d7a ("x86/alt: Support for automatic padding calculations")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger@xenproject.org>
2026-09-03 11:00:05 +02:00
Jan Beulich 769263b124 xhci-dbc: don't cast away const-ness in xhci_find_dbc()
Doing so (at the return statement), besides being a bad idea anyway, is a
violation of Misra rule 11.8.

Make "xcap" have an initializer while adjusting the code anyway.

No functional change intended.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
2026-09-03 10:59:58 +02:00
Jan Beulich 2c3aaf0fe7 Arm64/GICv3: have gicv3_its_find_quirk() not cast away const-ness
Doing so violates Misra rule 11.8, while being entirely unnecessary here:
All callers already store the return value in pointer-to-const variables.

No functional change.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Michal Orzel <michal.orzel@amd.com>
2026-09-03 10:59:51 +02:00
Jan Beulich a36bde9a3a Arm/alternative: hide casting away of const
We want to patch the original call site, which memory-wise is unrelated
to the struct alt_instr * that we start from.

No functional change intended.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Michal Orzel <michal.orzel@amd.com>
2026-09-03 10:59:51 +02:00
Jan Beulich d5d126a225 x86/bitops: don't cast away volatile-ness
Doing so, besides being a bad idea in general, violates Misra rule 11.8.

No functional change intended.

Fixes: f1879b2c25 ("xen: introduce generic non-atomic test_*bit()")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Teddy Astie <teddy.astie@vates.tech>
2026-09-02 21:44:30 +01:00
Jan Beulich e85f3521a4 x86/time: avoid early uses of NOW() to return zero
Waiting loops like the one in flush_command_buffer() will degenerate to
infinite ones when used early enough for NOW() to still return constant
zero. Make sure the returned value at least monotonically increases. When
available, use nominal frequency values as initial approximation.

Do this only in get_s_time(), as producing a sane value in
get_s_time_fixed() for non-zero inputs won't be reasonably possible.
Put an assertion there.

Reported-by: Roger Pau Monné <roger.pau@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger@xenproject.org>
2026-09-02 15:15:46 +02:00
Jan Beulich 11f8d55624 x86/CPU: re-arrange tail of early_cpu_init()
Some early setup doesn't need re-doing after ucode load. Move the call to
initialize_cpu_data() slightly up and add a conditional return point.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger@xenproject.org>
2026-09-02 15:14:55 +02:00
Jan Beulich f2ff80877f x86/vRTC: support century field
Both ROMBIOS and SeaBIOS (with CONFIG_QEMU=y, as we build it) blindly
assume availability of this field (at its conventional index 0x32); OVMF
at least has code to inspect FADT. Hence we ought to have supported it
virtually forever.

As the index is beyond RTC_CMOS_SIZE, leverage the padding field in
struct hvm_hw_rtc to hold its value. Update the field only when involved
values are valid BCD century specifiers. Otherwise (for VMs migrated in
from an older hypervisor) leave handling to the DM.

This makes the Linux rtc-cmos driver report y3k compatibility.

In the new rtc_check(), besides checking the new fields also check the
pre-existing pad0 field.

While extending xen-hvmctx.c:dump_rtc() also add RTC offset there.

Fixes: 4ca1612143 ("[HVM] Move RTC emulation into the hypervisor")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger@xenproject.org>
2026-09-02 15:14:08 +02:00
Jan Beulich dc2382d1a5 x86/vRTC: the use_timer field is a boolean one
... and hence wants to be of bool type.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger@xenproject.org>
2026-09-02 15:12:53 +02:00
Jan Beulich b244971a8b time: shorten year determination loop
For dates very far into the future (the MC146818 RTC's century byte can go
up to the 99th century), the present year-wise loop would become somewhat
inefficient (taking perhaps several thousand iterations). Prefix that loop
with a 400-year granular calculation (somewhat like the earlier loop does
for dates in the past).

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger@xenproject.org>
2026-09-02 15:12:14 +02:00
Jan Beulich 9d2bbfb797 x86/time: CMOS RTC may run in binary mode
Indicating it would always use BCD mode is just wrong (and then the
comment there said the opposite). All halfway recent (and really all 64-
bit capable) systems having a CMOS RTC should properly indicate the mode
in control register B.

Make use of the flag, but provide a fallback mechanism in case people run
into systems not matching the above assumption. Additionally, when binary
mode is indicated and when "cmos-rtc-probe" is in use (but "cmos-rtc-bcd"
isn't), probe whether the clock really runs in binary mode. (This probing,
sadly, can take up to 10 seconds.)

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger@xenproject.org>
2026-09-02 15:11:50 +02:00
Jan Beulich 2b434157fb PCI/physdev: address Misra 2.1 rule violation
Cases 0..3 are handled, and a 2-bit mask is applied to the switch()
expression. Therefore the default: case is reported unreachable by Eclair.
Insert BUILD_ERROR() to annotate this for Eclair.

No functional change.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
2026-09-01 10:00:48 +02:00
Jan Beulich 13d1c89e04 Eclair: deviate BUILD_ERROR() wrt rule 2.1 and introduce variants
BUILD_ERROR() is even stronger a guard than assertions in general, and
ASSERT_UNREACHABLE() (or BUG()) in particular. Deviate it just like those
to allow use for marking unreachable portions of code.

In some cases code being unreachable is dependent upon configuration.
Introduce two variants, as constructs like

    if ( IS_ENABLED(CONFIG_...) )
        BUILD_ERROR("...");

results in the if() still being reported as unreachable. Sadly these two
new macros introduce a new 20.12 violation each, which hence also needs
deviating.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Nicola Vetrini <nicola.vetrini@bugseng.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
2026-09-01 10:00:34 +02:00
Jan Beulich 6852334f84 Arm/GIC: add noreturn in a few more places
LPI related functions having just BUG() in them are disliked by Misra /
Eclair, as long as they don't also have a noreturn attribute.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
2026-09-01 10:00:01 +02:00
Jan Beulich f35d7e08ce altp2m: address Misra 2.1 rule violation
The stub altp2m_vcpu_idx() is recognized as "noreturn" function lacking
respective annotation (or having a return statement), which hence is deemed
unreachable code by Misra / Eclair. All call sites are guarded by
altp2m_active() checks, hence an inline function isn't needed. A
declaration will suffice, with call sites then getting DCE-d.

No functional change.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
2026-09-01 09:59:12 +02:00
Jan Beulich a1435a677c x86/IO-APIC: address Misra 2.1 rule violations
In both functions cases 0..3 are handled, and a 2-bit mask is applied to
the switch() expression. Therefore the default: cases are reported
unreachable by Eclair. Subsume the "case 2" blocks each into the
corresponding default ones.

While there also drop all the pointless figure braces inside the various
case blocks, inserting blank lines instead between them.

No functional change.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Nicola Vetrini <nicola.vetrini@bugseng.com>
2026-09-01 09:58:45 +02:00
Jan Beulich c014089815 RISC-V: place .sdata / .srodata / .riscv.attributes
Of the short-data sections, only .sbss is presently mentioned in the
linker script. Place them next to, but ahead of their "normal" data
sections.

.riscv.attributes can go towards the tail of the image, next to (ahead of)
debug info.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
2026-09-01 09:55:13 +02:00
Jan Beulich 72aa7d65b6 XSM: make Argo hooks well-formed ones
For whatever reason they didn't have an xsm_default_t first argument (to
cope with XSM=n mode), making it impossible to (easily) cover them in
xsm/hooks.h.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
Acked-by: Daniel P. Smith <dpsmith@apertussolutions.com>
2026-09-01 09:54:46 +02:00
Jan Beulich 8eb26a701b XSM: convert "allow" (Flask: "access") parameters to bool
These are boolean, so they should always have used bool (originally
bool_t), not uint8_t. Leverage recent changes to arrange for this with
(now) fewer places which need changing (within the XSM machinery itself).
Adjust call sites as well, where the conversion wasn't done so far.

While doing this, rename flask_io{port,mem}_mapping()'s last parameters to
"map".

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Daniel P. Smith <dpsmith@apertussolutions.com>
2026-09-01 09:53:40 +02:00
Jan Beulich c0308bdfb7 XSM: make xsm_default_action() const-correct
To be able to properly use const on dummy hook function parameters, add
const to both domain pointers.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
Acked-by: Daniel P. Smith <dpsmith@apertussolutions.com>
2026-09-01 09:52:45 +02:00
Jan Beulich 08149ec555 x86/IO-APIC: replace redundant irq_trigger() call
Just having called the function and stored the result, there's no point in
calling it again right away with the same argument; the stored result can
be used instead. And the stored result also doesn't need overwriting again
with the same value.

No functional change intended.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2026-08-27 08:06:39 +02:00
Jan Beulich 829d67e244 x86emul/fuzz: sanitize CR4 values
While the CPU policy is obtained from hardware, the CRn values to start
with are taken from fuzzed input. Since most CR4 bits can only be set when
the respective feature is indicated as available by CPUID, the emulator
often only checks the CR4 bit. Without sanitization, assertions like the
one in emul_test_read_xcr() (checking XSAVE support) could therefore
trigger.

Omit most paging-only bits from sanitization, as the core emulator doesn't
itself walk page tables. LA57 wants checking for the bit being used by
CANONICALIZE_MAYBE().

Reported-by: Andrew Mbugua <andrewprecious388@gmail.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2026-08-26 14:14:03 +02:00
Jan Beulich 45bc5330a3 x86/Intel: split model-specific freq calculation off of intel_log_freq()
..., for that logic to become reusable. While doing so undo the open-
coding of DIV_ROUND_UP(). Also switch to the new struct cpuinfo_x86 field
names.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger@xenproject.org>
2026-08-19 11:56:53 +02:00
Jan Beulich 6e3102caac time: add "NOW() good" indicator
printk_start_of_line() checks for a value of 0 right now. In order to be
able to have NOW() return at least monotonically increasing values, that
needs replacing by an explicit indicator.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
Acked-by: Roger Pau Monné <roger@xenproject.org>
Reviewed-by: Michal Orzel <michal.orzel@amd.com>
2026-08-19 11:55:58 +02:00
Jan Beulich 5e2bbb53f5 XSM: make XSM hooks well-formed ones
For whatever reason they didn't have an xsm_default_t first argument (to
cope with XSM=n mode), making it impossible to (easily) cover them in
xsm/hooks.h.

flask_do_xsm_op() is also changed to return int, as all the function ever
returns is an int. This way no new machinery needs adding to xsm/hooks.h.
Instead one piece of compat machinery can then be dropped from
xsm/flask/flask_op.c.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Daniel P. Smith <dpsmith@apertussolutions.com>
2026-08-17 09:23:57 +02:00
Jan Beulich 7f659ae00a XSM: suppress hypercall when XSM=n
This can be easily done in hypercall-defs.c, thus avoiding the need to
dive into xsm/ when building Xen, just to add code which does what is done
for an absent hypercall handler anyway (returning -ENOSYS).

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Daniel P. Smith <dpsmith@apertussolution.com>
2026-08-17 09:23:18 +02:00
Jan Beulich 60a90fd5b6 XSM/dummy: drop redundant return statements
They're meaningless when no value is returned.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Daniel P. Smith <dpsmith@apertussolutions.com>
2026-08-17 09:22:53 +02:00
Jan Beulich 2824c819c6 XSM/dummy: fold cf_check into XSM_INLINE
Use of cf_check together with always_inline is pretty pointless, and with
XSM=n none of the dummy handlers are supposed to have their address taken.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Daniel P. Smith <dpsmith@apertussolutions.com>
2026-08-17 09:22:24 +02:00
Jan Beulich 0a249bcb02 x86: reduce dependencies on x86_emulate/x86_emulate.h
Split out struct x86_event to an entirely separate header, and move a few
other items describing the architecture to a new x86-types.h. With a few
forward decls of structures and with a fair number of new #include-s in
.c files, the inclusion of x86_emulate.h (and hence
x86_emulate/x86_emulate.h) can be dropped from all header files except
hvm/emulate.h; it needs additionally adding to hvm/ioreq.h though.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2026-08-13 15:12:51 +02:00
Jan Beulich 1077a93425 radix-tree: drop radix_tree_init_maxindex()
Radix trees are in principle usable as soon as memory allocation works.
(Radix trees with only index 0 populated are usable even earlier.) If only
there wasn't height_to_maxindex[], which is filled only by a pre-SMP
initcall. The benefit of this array is rather limited - the calculations
done by __maxindex() can as well be done by radix_tree_maxindex(); the
overhead isn't all this high.

This was found by UBSAN on a multi-segment system:

(XEN) UBSAN: Undefined behaviour in common/radix-tree.c:83:27
(XEN) index 12 is out of range for type 'long unsigned int [12]'
...
(XEN) Xen call trace:
(XEN)    [<ffff82d040323f9c>] R common/ubsan/ubsan.c#ubsan_epilogue+0xa/0xd5
(XEN)    [<ffff82d040324d91>] F __ubsan_handle_out_of_bounds+0x9d/0xd4
(XEN)    [<ffff82d04029265a>] F radix_tree_insert+0x24d/0x570
(XEN)    [<ffff82d04037ac3e>] F drivers/passthrough/pci.c#alloc_pseg+0xc4/0x165
(XEN)    [<ffff82d040a3b526>] F pci_add_segment+0xc/0x1b
(XEN)    [<ffff82d040a5ad1b>] F acpi_parse_mcfg+0x29b/0x344
(XEN)    [<ffff82d040a3f612>] F acpi_table_parse+0x5d/0x92
(XEN)    [<ffff82d040a5bf55>] F acpi_mmcfg_init+0x3a2/0x71d
(XEN)    [<ffff82d040a71ba6>] F pci_setup+0x17/0x29
(XEN)    [<ffff82d040a784d0>] F __start_xen+0x394c/0x4ed8
(XEN)    [<ffff82d040423057>] F __high_start+0xb7/0xb8

Fixes: 21844b0e32 ("PCI multi-seg: introduce notion of PCI segments")
Fixes: 8dc6738dbb ("Update radix-tree.[ch] from upstream Linux to gain RCU awareness")
Reported-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2026-08-05 12:00:17 +02:00
Jan Beulich 5b965555b1 XSM: make certain x86-specific hooks dependent upon PV=y
They're unreachable / dead otherwise.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Daniel P. Smith <dpsmith@apertussolutions.com>
2026-08-03 16:36:54 +02:00
Jan Beulich 7d15b10f6c XSM: make .dm_op() hook dependent upon IOREQ_SERVER=y
It's unreachable / dead otherwise.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Daniel P. Smith <dpsmith@apertussolutions.com>
2026-08-03 16:36:34 +02:00
Jan Beulich 29df230854 XSM: make .hvm_param*() hooks dependent upon HVM=y
They're unreachable / dead otherwise.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Daniel P. Smith <dpsmith@apertussolutions.com>
2026-08-03 16:36:13 +02:00
Jan Beulich 754ae0860a XSM: make .hvm_altp2mhvm_op() hook dependent upon ALTP2M=y
It's unreachable / dead otherwise.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Daniel P. Smith <dpsmith@apertussolutions.com>
2026-08-03 16:35:54 +02:00
Jan Beulich dd60120e2a XSM: make .hypfs() hook dependent upon HYPFS=y
It's unreachable / dead otherwise.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Daniel P. Smith <dpsmith@apertussolutions.com>
2026-08-03 16:35:32 +02:00
Jan Beulich 430673b845 XSM: make .kexec() hook dependent upon KEXEC=y
It's unreachable / dead otherwise.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Daniel P. Smith <dpsmith@apertussolutions.com>
2026-08-03 16:35:12 +02:00
Jan Beulich 7a01c8179c XSM: make .iomem_mapping_vpci() hook dependent upon HAS_VPCI=y
It's unreachable / dead otherwise.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Daniel P. Smith <dpsmith@apertussolutions.com
2026-08-03 16:34:50 +02:00
Jan Beulich d9605dee5c XSM: make PCI hooks dependent upon HAS_PCI=y
They're unreachable / dead otherwise. Really resource_{,un}plug_pci() is
further limited to PCI pass-through.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Daniel P. Smith <dpsmith@apertussolutions.com>
2026-08-03 16:34:32 +02:00
Jan Beulich 51eaa9d1a8 XSM: make .{,un}map_domain_pirq() hooks dependent upon HAS_PIRQ=y
They're unreachable / dead otherwise.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Daniel P. Smith <dpsmith@apertussolutions.com>
2026-08-03 16:32:44 +02:00
Jan Beulich d1d1287764 XSM: make .grant_*() hooks dependent upon GRANT_TABLE=y
They're unreachable / dead otherwise.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Daniel P. Smith <dpsmith@apertussolutions.com>
2026-08-03 16:32:25 +02:00
Jan Beulich 813a62811f XSM: reduce redundancy in hook machinery
Hook definition (in struct xsm_ops), wrappers, dummy_ops, and flask_ops
need keeping in sync (including any involved #ifdef-ary), i.e. require
consistent adjustments in multiple places when a change is necessary.
Reduce this by introducing a multi-use helper header file. (However,
hooks not taking xsm_default_t as first argument in the wrappers aren't
covered.)

As there's some re-arrangement of field order in struct xsm_ops anyway,
also group together everything depending on SYSCTL=y. Similarly move
.mem_sharing_op() into the MEM_SHARING conditional.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Daniel P. Smith <dpsmith@apertussolutions.com>
2026-08-03 14:22:22 +02:00
Jan Beulich 9462d81b6e x86emul: split vex_np from vex_none
..., undoing the aliasing between two distinct enums, and more in line
with how the SDM nowadays names things.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2026-08-03 09:50:59 +02:00
Jan Beulich aa2f6c99f3 x86/cpu-policy: set up host policy earlier
In order to use cpu_has_* expanding to host_cpu_policy.*, the host policy
needs setting up alongside boot_cpu_data.x86_capability[]. Arrange for
that towards the end of identify_cpu(). Then make sure .x86_capability[]
and host policy remain in sync when setup_{force,clear}_cpu_cap() are
used.

Rename the function now it's no longer static.

Fixes: 894bd76179 ("x86/Intel: use host CPU policy for ARAT checking")
Reported-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-Acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
2026-07-29 16:02:31 +02:00
Jan Beulich 75f920bd47 pygrub: security-supported only when run de-privileged
XSA-443 and XSA-497 addressed specific issues in specific file system
drivers (libfsimage) used by pygrub. Further issues were reported, and yet
more are to be expected. XSA-443 introduced a means to run pygrub de-
privileged. Only this mode of operation is security supported from now on.

This is XSA-508.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
2026-07-28 12:40:10 +01:00
Jan Beulich 2afa6fea9d vNUMA: close race window in domain cleanup
Calling vnuma_destroy() without any locking can race the handling of both
XENMEM_get_vnumainfo and XEN_DOMCTL_setvnumainfo. While the latter is,
without Flask, strictly only exposed to the control domain, the former
can also be invoked by a stubdom DM or a de-privileged DM running in the
control domain. Isolate the logic used by XEN_DOMCTL_setvnumainfo into a
new helper function, which then is also used from domain_kill(). While
doing so also move the vnuma_destroy() invocation out of the locked
region.

With d->vnuma properly cleared by domain_kill(), XENMEM_get_vnumainfo now
really only needs to check for the field being NULL. That check needs
repeating, though, after re-acquiring the lock.

This is CVE-2026-62429 / XSA-502.

Fixes: 9695014966 ("xen: vnuma topology and subop hypercalls")
Reported-by: Teddy Astie <teddy.astie@vates.tech>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
2026-07-28 12:40:10 +01:00
Jan Beulich 96dfeb4177 gnttab: cope with version changes racing other operations
Dropping and re-acquiring the grant table lock for a particular operation
requires special care, as in the meantime the grant table version can
change.

During a v2 -> v1 change, status frames going away means that pre-
calculated status pointers go stale, referencing freed (and possibly
already re-used) memory. Record in-flight v2 operations, permitting the
version change only when there are none of them. Recalculate "status" in
the one place (map_grant_ref()'s error path) where it could be stale, but
confine this to reserved entries.

This is CVE-2026-62436.

Reported-by: Mark Esler <mark@hexproof.dev>

During a v1 -> v2 change, the number of shared table entries reduces,
meaning that previously validated grant references may now be out of
bounds. Because of the checking of pin counts in gnttab_set_version()
(with the grant table lock held for writing), for now-out-of-bounds gref-s
neither active mappings can exist, nor can there be in-progress copy
operations. Nevertheless bounds checks are added there, just to be on the
safe side.

For gnttab_transfer(), to cover the gap between the lock being dropped by
gnttab_prepare_for_transfer() and it being re-acquired, have the helper
return the version it found, and fail the operation if the version turns
out to have changed after re-acquiring the lock.

Further avoid needless use of shared_entry_header(), as it involves
pointer arithmetic which, when using an out-of-bounds ref, is UB.

This is CVE-2026-62435.

Everything together is XSA-501.

Fixes: a98dc13703 ("Introduce a grant_entry_v2 structure")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Tested-by: Mark Esler <mark@hexproof.dev>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2026-07-28 12:40:10 +01:00
Jan Beulich 61b0a59ce2 gnttab: check values against active entry when copying an already-pinned one
acquire_grant_for_copy() passes to its caller both an MFN and a struct
page_info *. The two really need to be in sync for the get_page()
underlying get_paged_frame() and get_page_type() (both acting on the
passed back struct page_info *) and the map_domain_page() (acting on the
passed back MFN) to achieve the intended effect.

Go further and also check other properties: GTF_transitive / GTF_sub_page
may have been flipped in the shared entry, so respective fields / values
also may not match.

The one field which we can be sure does match (as it was checked earlier
in the function) is ->domid. Add an assertion nevertheless.

This is CVE-2026-62428 / XSA-500.

Fixes: d8cbecb1ee ("grant-tables: Use get_page_from_gfn() instead of get_gfn()/put_gfn")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
2026-07-28 12:40:10 +01:00
Jan Beulich 299de2aeda sysctl/XSM: drop .page_offline() hook
Integrate the checking with xsm_sysctl(), now that it has the full op
struct passed. As a positive side effect, permissions are then checked at
the same early point with and without Flask.

This is part of CVE-2026-62426 / XSA-499.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-By: Daniel P. Smith <dpsmith@apertussolutions.com>
2026-07-28 12:40:10 +01:00
Jan Beulich 0501e1dc04 sysctl/XSM: drop .resource_{,un}plug_core() hooks
Integrate the checking with xsm_sysctl(), now that it has the full op
struct passed. As a positive side effect, permissions are then checked at
the same early point with and without Flask. Note that these were x86-
only, i.e. some dead/unreachable code gets eliminated for (in particular)
Arm.

This is part of CVE-2026-62426 / XSA-499.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-By: Daniel P. Smith <dpsmith@apertussolutions.com>
2026-07-28 12:40:10 +01:00
Jan Beulich 4b249cba4b sysctl/XSM: drop .readconsole() hook
Integrate the checking with xsm_sysctl(), now that it has the full op
struct passed. As a positive side effect, permissions are then checked at
the same early point with and without Flask.

This is part of CVE-2026-62426 / XSA-499.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-By: Daniel P. Smith <dpsmith@apertussolutions.com>
2026-07-28 12:40:10 +01:00
Jan Beulich 3179bf2931 sysctl/Flask: add preliminary check for XEN_SYSCTL_getdomaininfolist
To shield the sysctl lock from abuse by unauthorized domains, follow what
5154fdda11 ("domctl: protect locking for get_domain_state") did: Check
for permission to issue the operation against DOM_XEN in flask_sysctl().
The finer-grained xsm_getdomaininfo() later in the handling of the sub-op
remains unaltered.

In the in-tree policy respective permission therefore needs granting.

This is part of CVE-2026-62426 / XSA-499.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Daniel P. Smith <dpsmith@apertussolutions.com>
2026-07-28 12:40:10 +01:00
Jan Beulich 751e371c91 sysctl/XSM: drop .scheduler_op() hook
Integrate the checking with xsm_sysctl(), now that it has the full op
struct passed. As a positive side effect, permissions are then checked at
the same early point with and without Flask.

This is part of CVE-2026-62426 / XSA-499.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-By: Daniel P. Smith <dpsmith@apertussolutions.com>
2026-07-28 12:40:10 +01:00
Jan Beulich 9f4aa6d00a sysctl/XSM: pass full struct xen_sysctl to xsm_sysctl()
Subsequently some sub-ops will want to inspect their sub-sub-ops.

This is part of CVE-2026-62426 / XSA-499.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Daniel P. Smith <dpsmith@apertussolutions.com>
2026-07-28 12:40:10 +01:00
Jan Beulich 4ef45cbe31 platform-op/XSM: move resource-{,un}plug-core checks
Integrate the checking with flask_platform_op(); there never really was a
need to defer these checks, as the sub-op has always been known to the
function. As a positive side effect, permissions are then checked at the
same early point with and without Flask.

This is CVE-2026-62427 / part of XSA-499.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-By: Daniel P. Smith <dpsmith@apertussolutions.com>
2026-07-28 12:40:10 +01:00
Jan Beulich f2cac32029 x86: SHADOW_PAGING is deprecated
Addressing certain issues, in particular related to operations which may
take excessively long and therefore would need preemption, has turned out
overly costly. Since alternatives (HVM/PVH: HAP, PV: shim) are commonly
available, the decision was to deprecate the functionality, while still
retaining it for people to use at their own (security) risk. Memory-wise
small enough guests may still be okay to run.

Some CI testing depends on SHADOW_PAGING.  Explicitly enable it when needed.

This is CVE-2026-42493 / XSA-495.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
2026-07-28 12:40:10 +01:00
Jan Beulich 25cf3956b2 x86emul: drop host_and_vcpu_must_have()
With CPU policy dependency logic now properly in place and working, and
with us never enabling ISA bits in guest policies which the underlying
hardware doesn't support, the dual checks aren't needed anymore.

In turn, a number of cpu_has_* can then also go away, when their only user
was the emulator code.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2026-07-28 10:16:00 +02:00
Jan Beulich 59b18eb757 x86emul: support non-SIMD MOVRS
As we ignore cachability aspects of insns, they're treated like simple
MOVs.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2026-07-28 10:07:13 +02:00
Jan Beulich fa61af950b x86/HVM: more checking for XEN_DOMCTL_ioport_mapping
When adding ranges, only alter existing ones when there is an exact match.
Don't accept ranges overlapping existing ones.

When removing ranges, only remove a range if there's an exact match.
Return an error when the range isn't found.

Fixes: 192c4dabc3 ("domctl and p2m changes for PCI passthru")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
2026-07-22 09:29:48 +02:00
Jan Beulich 3845d3854d x86/domctl: don't imply I/O port permissions from I/O port mapping
Rather than granting permissions when mapping (an operation that DM-s are
allowed to carry out, while they can't invoke ioport-permission), check
whether permissions actually were granted when adding a mapping. This then
also allows relaxing the necessary locking.

While no longer granting permissions upon mapping is "only" at risk of
breaking guests, no longer revoking permissions upon unmapping strictly
requires callers to additionally invoke XEN_DOMCTL_ioport_permission. Or
else a security issue would arise. In-tree code already does so.

While there switch to using %pd in the two log messages.

Fixes: 192c4dabc3 ("domctl and p2m changes for PCI passthru")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger@xenproject.org>
Acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
2026-07-22 09:29:09 +02:00
Jan Beulich 388497e5f9 non-x86: sync tidying logic at end of linking
Mirror what 761bb575ce ("x86: fix build race when generating temporary
object files") did there to other ports: These ..*.cmd files aren't useful
to have/keep.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Oleksii Kurochko <oleksii.kurochko@gmail.com> # riscv
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
Reviewed-by: Michal Orzel <michal.orzel@amd.com>
2026-07-22 09:26:36 +02:00
Jan Beulich 66a9aa12e7 x86emul: prune an excess EVEX.Z check
DstMem processing early in x86_emulate() raises #UD when EVEX.Z is set
with a memory destination. Open-coded checks like this one are therefore
dead / unreachable code, violating Misra rules.

Fixes: 4037a62ef9 ("x86emul: support AVX512F floating-point conversion insns")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2026-07-21 09:48:04 +02:00
Jan Beulich 42c0972e9b x86emul: drop dead conditional from decode
We know that opcode_table[0x0f] is 0, there's no need to check that. Up
until ab082ffa87 ("x86emul: generate and make use of a canonical opcode
representation") or maybe already c4e7a67e3a ("x86emul: drop
SrcInvalid") this may have been justified, but it no longer is.

This eliminates a Misra C:2012 rule 2.2 ("There shall be no dead code")
violation.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2026-07-21 09:46:01 +02:00
Jan Beulich cf90c8a48a x86emul: V{,P}{COMPRESS,EXPAND}* can (wrongly) trigger assertion
AFL has pointed out that the op_bytes-is-not-0 assertion in common SIMD
handling can trigger for these insns. Indeed when the (relevant part of)
the controlling mask register is 0, no memory is accessed at all. Leave
op_bytes unaltered in this case, to engage the short-circuiting in common
SIMD handling when fault_suppression is true and op_bytes is 0.

While there also correct a related typo in the test harness.

Fixes: 65f82d4ce1 ("x86emul: support AVX512{F,_VBMI2} compress/expand insns")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2026-07-20 09:50:00 +02:00
Jan Beulich c363ac025c x86: put x86_emulate/ early in $(obj-y)
... such that in parallel builds make would schedule it early.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Teddy Astie <teddy.astie@vates.tech>
2026-07-16 09:18:01 +02:00
Jan Beulich c5b4ba49a3 x86emul: drop wrapper C file
Move the little bit that's still left in x86/x86_emulate.c into a __XEN__
conditional in x86/x86_emulate/x86_emulate.c. Move what are roughly the
test/fuzzing harness counterparts from there into the corresponding #else.

Interestingly more recent gcc takes issue with three static const arrays
which are unused when HVM=n (noticeable in particular in the shim build).
Apparently such are diagnosed only when present in the top-level file, but
not when living in an #include-d one.

Requested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Teddy Astie <teddy.astie@vates.tech>
2026-07-16 09:17:23 +02:00
Jan Beulich e58a8e0889 x86/HVM: don't (almost) open-code POP_GPRS
It can be used as-is for VMX. For SVM the special treatment of %rax needs
accounting for.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2026-07-06 09:42:46 +02:00