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>
When removing a CPU from a cpupool running the credit scheduler, a
race might happen between schedule_cpu_rm() and csched_timer(),
resulting in a NULL dereference.
The timer associated with csched_timer() is killed only in
csched_deinit_pdata(), which is called by schedule_cpu_rm() after
setting the scheduler's per-cpu data to NULL AND after enabling
interrupts again. This can result in the timer firing before being
killed, so csched_timer() needs to test the per-cpu data being set
before accessing it.
Fixes: 78be3dbbfe ("cpupools [1/6]: hypervisor changes")
Reported-by: Dietmar Hahn <dietmar.hahn@fujitsu.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-Acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
(cherry picked from commit ea1d785a5f)
Add the missing ARM logic, populating xen_arm_arch_domainconfig
from the raw xc_domaininfo_t the same way the x86 branch does for
xen_x86_arch_domainconfig.
Fixes: 9d683b5e37 ("tools/ocaml: Expose arch_config in domaininfo")
Fixes: 81838c9067 ("ocaml: fix arm build")
Signed-off-by: Julian Vetter <julian.vetter@vates.tech>
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Teddy Astie <teddy.astie@vates.tech>
Release-Acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
(cherry picked from commit 01b4b39e2e)
The Store_field(result, 16, arch_config) sits inside an #ifdef x86, meaning
that on other architectures the pointer is not filled in. Ocaml code then
falls over a NULL(ish) pointer (really the Val_unit used to initialise
'result') when the layout in the heap doesn't match the type system.
Rearrange alloc_domaininfo() to avoid this. Similarly to
physinfo_arch_caps(), raise an exception if the architecture code hasn't
filled in an appropriate tag. Move the setup of arch_domainconfig to be
common logic.
In order to simplify the addition of other architectures, remove the
arch_config variable (reusing tmp as it's touched exactly once), and rename
x86_arch_config to be arch_config so each architecture can fill in a suitable
one without needing more local variables.
Fixes: 9d683b5e37 ("tools/ocaml: Expose arch_config in domaininfo")
Fixes: 81838c9067 ("ocaml: fix arm build")
Reported-by: Julian Vetter <julian.vetter@vates.tech>
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Teddy Astie <teddy.astie@vates.tech>
Release-Acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
(cherry picked from commit 365d2a5be3)
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>
(cherry picked from commit 75f920bd47)
When doing PoD cache reclaim as part of a decrease reservation call, avoid
reclaiming special pages for the PoD cache. Otherwise such pages get moved
from the domain ->xenpage_list to the ->page_list, while still being
referenced in ->shared_info domain field.
Prevent PoD cache from reclaiming special pages, as nothing good can come
out of it.
This is XSA-507 / CVE-2026-62434.
Fixes: 41aa0b6269 ("PoD memory 4/9: Decrease reservation")
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
(cherry picked from commit 372497ce42)
The hypercall requires at least one input buffer, as both arch-specific
implementations of dm_op() unconditionally assume ->buf[0] to be valid (and
not stack rubble).
Additionally, XEN_DMOP_modified_memory requires two input buffers, yet the
code was assuming the second buffer to always be provided by the user when
checking for the number of extents. In case the caller sets nr_bufs to 1,
the code in modified_memory() will read stack garbage as the size of the
buffer, thus allowing the caller some degree of insight on the contents of
the stack by probing whether the hypercall returns -EINVAL or -EFAULT as a
result of such bogus call.
This is XSA-506 / CVE-2026-62433.
Fixes: e3b93b3c59 ("dmop: add xendevicemodel_modified_memory_bulk()")
Fixes: 85cb15dfe4 ("x86/hvm/dmop: only copy what is needed to/from the guest")
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
(cherry picked from commit aef948a300)
evtchn_fifo_expand_array() will check for the domain evtchn_fifo being
populated without holding the event_lock, which can lead to a race with a
concurrent evtchn_reset().
Ensure the checking for evtchn_fifo presence is done while holding the
event_lock.
This is XSA-505 / CVE-2026-62432.
Fixes: 400b3bd642 ("evtchn: make EVTCHNOP_reset suitable for kexec")
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
(cherry picked from commit 0e9d647aca)
Otherwise in periodic mode a division by 0 would happen on the second call
to start_stimer() when using periodic mode.
Note that the HyperV specification states: "Writing the value zero to the
Count register will stop the counter, thereby disabling the timer,
independent of the setting of AutoEnable in the configuration register."
so a timer with a 0 count should never be in the enabled state.
This is XSA-504 / CVE-2026-62431.
Fixes: 26fba3c855 ("viridian: add implementation of synthetic timers")
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
(cherry picked from commit ff7d9aa77e)
Do the checking for a valid CMOS index while holding the spinlock,
otherwise the value could be changed by the guest after having been
checked.
This is XSA-503 / CVE-2026-62430.
Fixes: 34bef0e6d5 ("hvm: Add locking to platform timers.")
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
(cherry picked from commit 52350da926)
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>
(cherry picked from commit 2afa6fea9d)
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>
(cherry picked from commit 96dfeb4177)
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>
(cherry picked from commit 61b0a59ce2)
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>
(cherry picked from commit 299de2aeda)
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>
(cherry picked from commit 0501e1dc04)
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>
(cherry picked from commit 4b249cba4b)
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>
(cherry picked from commit 3179bf2931)
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>
(cherry picked from commit 751e371c91)
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>
(cherry picked from commit 4ef45cbe31)
The directory and Rock Ridge / SUSP walk in iso9660_dir() derives several
lengths directly from attacker-controlled on-disk fields without validating
them. libfsimage is used by pygrub, which parses the filesystem of an
untrusted guest disk image from dom0, so these are reachable across a trust
boundary.
Five related problems are addressed:
* The directory record loop advances by
idr = (char *)idr + idr->length.l
and only stops on length.l == 0. A record whose length is smaller than
the fixed part of the on-disk layout cannot hold its own mandatory
fields, yet the body still reads name_len/extent/size and computes the
System Use area length from it. Require length to cover at least the
fixed record (sizeof(*idr) - sizeof(idr->name)) before entering the body.
This is CVE-2026-42494.
* The System Use area length is computed before the inner loop as
rr_len = idr->length.l - idr->name_len.l
- sizeof(struct iso_directory_record) + sizeof(idr->name);
in unsigned arithmetic. If length.l is smaller than name_len.l plus the
fixed record size, rr_len underflows to a huge value and the whole SUSP
walk runs off the directory buffer. Guard the subtraction and treat such
records as having no System Use area.
This is CVE-2026-42495.
* Inside the loop, each entry is consumed with
rr_len -= rr_ptr.rr->len;
rr_ptr.ptr += rr_ptr.rr->len;
with no lower or upper bound on the entry's own len byte. A len of 0
spins forever; a len greater than the remaining rr_len underflows it and
walks past the buffer. Validate 4 <= len <= rr_len at the top of the
loop and stop on violation: a structurally broken entry stream cannot be
advanced reliably, so continuing is not meaningful.
This is CVE-2026-62423.
* The NM handler subtracted the 5-byte SUSP/NM header from len without a
lower-bound check, underflowing name_len (the original report). The
generic check above only guarantees len >= 4; NM has an extra flags byte,
so keep an NM-specific len >= 5 check.
This is CVE-2026-62424.
* The CE continuation resets rr_ptr/rr_len from ce.offset and ce.size, both
image-controlled, into the fixed single-sector RRCONT_BUF with no bounds
check. Reject a window that does not fit in the buffer.
This is CVE-2026-62425.
This is XSA-497.
Signed-off-by: Syed Abdul Khaliq <abdul@bugqore.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
(cherry picked from commit fd11acab3d)
There is a corner case in the error path of evtchn_bind_virq() (handling
EVTCHNOP_bind_virq hypercall) which allows unprivileged domains to
interfere with privileged ones: If an unprivileged domain allocates all
available ports to reach "no more ports available" and then issues an
EVTCHNOP_bind_virq hypercall to bind any allowed VIRQ (e.g. VIRQ_DEBUG),
domain_deinit_states() will be called despite not having called
domain_init_states().
To fix the issue move domain_deinit_states(d) under the same condition as
used for the domain_init_states() call.
This is CVE-2026-42492 / XSA-496.
Fixes: f94360a7fe ("xen: add bitmap to indicate per-domain state changes")
Signed-off-by: Grygorii Strashko <grygorii_strashko@epam.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
(cherry picked from commit 40c59b6c29)
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>
(cherry picked from commit f2cac32029)
A privileged domain on Arm64 can trigger a data abort in the hypervisor
by issuing memory_op's XENMEM_add_to_physmap_batch sub-op with
space=XENMAPSPACE_gmfn_foreign, idx=0 and foreign_domid=DOMID_IO.
get_pg_owner(DOMID_IO) succeeds, returning a pointer to the dom_io
pseudo-domain. The subsequent get_page_from_gfn(dom_io, ...) then
attempts to walk dom_io's P2M table, which is not initialized for
pseudo-domains, resulting in a data abort in p2m_get_entry() when
it dereferences the invalid pointer returned by p2m_get_root_pointer().
Replace get_pg_owner() with explicit domain lookup logic matching
the x86 implementation: handle DOMID_XEN via rcu_lock_domain(dom_xen),
and resolve all other domain IDs via rcu_lock_remote_domain_by_id(),
which rejects pseudo-domains (DOMID_IO, etc.) that are not present in
the domain hash, returning -ESRCH before any P2M access occurs.
Fixes: 615897bc6c ("xen/arm: Allow a privileged domain to map foreign page from DOMID_XEN")
Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Reviewed-by: Michal Orzel <michal.orzel@amd.com>
Release-Acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
(cherry picked from commit f795a9c491)
Commit 9f892f84c2 ("x86/domctl: Stop using XLAT_cpu_user_regs()")
converted memcpy() of the cpu_user_regs structure to explicit copy of
its fields. In the compat case, it intentionally missed few of them,
named in the commit message. But the 64bit case missed also r8-r15
registers, which was not intentional. This, at least, caused Linux
6.18.x crash when resuming PVH domU.
Fix it by adding missing assignments.
Fixes: 9f892f84c2 ("x86/domctl: Stop using XLAT_cpu_user_regs()")
Signed-off-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Teddy Astie <teddy.astie@vates.tech>
Release-acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
pv_map_ldt_shadow_page() takes the whole guest PTE, adds _PAGE_RW to it, then
installs it into Xen's pagetables. It has had this behaviour ever since LDT
support was added in 2003.
However, it allows the guest to control the software available bits and
cacheability. This happens to be benign right now, but is bad form.
Use only the guest frame, and construct the mapping as regular RW frame, and
notably includes NX. This is how the GDT logic already works.
Fixes: 005c272397 ("Finished virtualisation of x86 LDT")
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Release-Acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
(cherry picked from commit 1cc1f4d7a0)
A malformed partial DTB specifying both '#address-cells = <0>' and
'#size-cells = <0>' causes '(address_cells * 2 + size_cells)' to
evaluate to 0. This sum is subsequently used as a divisor when
calculating the number of regions in the 'xen,reg' property inside
handle_passthrough_prop():
len = fdt32_to_cpu(xen_reg->len) / ((address_cells * 2 + size_cells) *
sizeof(uint32_t));
This leads to a division by zero exception in the Xen hypervisor during
boot, causing a hypervisor panic/crash.
Fix this by validating that both 'address_cells' and 'size_cells'
are within the range of [1, 2] at the top of handle_passthrough_prop().
Any invalid cell size combination is safely rejected early with an error
message and return -EINVAL.
Furthermore, update handle_passthrough_prop() to use the sizeof(*cell)
instead of sizeof(uint32_t).
Fixes: 9ce974c475 ("xen/arm: assign devices to boot domains")
Signed-off-by: Dmytro Prokopchuk <dmytro_prokopchuk1@epam.com>
Reviewed-by: Michal Orzel <michal.orzel@amd.com>
Release-Acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
(cherry picked from commit b83e1d9a1a)
construct_domain() creates the secondary vCPUs in a loop, but on a
vcpu_create() failure it only prints a message and breaks out of the
loop returning success. As a result the domain can be partially
constructed with fewer vCPUs than d->max_vcpus. This causes two contract
violations:
- Xen-Guest: domain's FDT is generated before vCPU creation - Xen exposes
incorrect information (e.g. two vCPUs listed in a device tree while only
one is actually created),
- User-Xen: unlike x86, on Arm port we try to bail out as soon as
possible on unsatisfied user requests (e.g. user requested two vCPUs
for a domain but it was created with only one).
Return an error instead of breaking out of the loop. Both callers
(construct_domU() and construct_hwdom()) already propagate a negative
return value and fail domain construction.
Fixes: 6b0e8e4334 ("xen/arm: allocate secondaries dom0 vcpus")
Signed-off-by: Michal Orzel <michal.orzel@amd.com>
Reviewed-by: Ayan Kumar Halder <ayan.kumar.halder@amd.com>
Release-Acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
(cherry picked from commit e3aa330017)
Add new job-level EXTRA_XEN_OPTS variable, in addition to CONSOLE_OPTS.
FRED is not yet enabled by default on Intel systems, but is expected to
function. Explicitly turn it on for added test coverage in the short term.
Signed-off-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
(cherry picked from commit d9e36605ff)
For now run similar set of tests as ADL.
Exclude suspend test for now. While firmware claims S3 is supported,
suspend attempt fails (power LED blinks for a few seconds, and
then system reboots). With no messages on the serial console, even with
`sync_console`.
Signed-off-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
(cherry picked from commit 77ed730bfb)
This was reported to the security team, demonstrating that code execution
could be achieved, but without a demonstration of a priviliege boundary being
bypassed.
Still, it's a high risk path with no obvious evidence of having been used even
for debugging, so remove the environment variable and use the build time
$(libdir)/xenfsimage path only.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
Acked-by: Anthony PERARD <anthony.perard@vates.tech>
Release-Acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
(cherry picked from commit f0161d2d89)
These existed to work around a bug in older GCC when using struct-casting for
variable initialisation. However, our baseline toolchain is new enough to not
suffer this bug.
Removing these resolves two MISRA Rule 9.2 violations which exist in release
builds of Xen only, where "= { ... }" is disallowed for simple scalar
initialisation.
The BUILD_BUG_ON() in xenmem_add_to_physmap() cannot stay as it is, because
INVALID_GFN is not an Integer Constant Expression. Replace it BUILD_ERROR()
which is the nearest available alternative.
No functional change.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Michal Orzel <michal.orzel@amd.com>
Release-Acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
(cherry picked from commit e6b68789d4)
The current logic in ns16550_interrupt() will loop until the device sets
the NOINT in IIR. At least on the Lenovo ThinkSystem SR630 V4 the flow
control of the serial-over-lan emulated UART seems to be broken, as it
doesn't set the NOINT bit consistently. The Transmitter Holding Register
Empty in LSR also seems to not be properly signaled, as even with it set
writes to the transmit register take ~6ms. This leads to the watchdog
triggering very easily on such system.
Introduce an upper bound on the execution time of ns16550_interrupt(), this
is currently set as 4x the polling interval, which is calculated as the
time to fill RX FIFO and/or empty TX FIFO. The current maximum timeout is
either 5ms or the polling interval, whatever is higher. Once the timeout
triggers the interrupt is disabled and the uart is switched to polling
mode.
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Release-Acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
It's possible for IRQ_DISABLED to be set while running the handler
execution loop in do_IRQ(). Such disabling can be done by the handler
itself, or from a remote CPU.
Check for IRQ_DISABLED not being set in the loop condition, as to not
execute the handler if the IRQ has been disabled.
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Release-Acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
In preparation for irq_to_desc() being called by common IRQ code.
PowerPC doesn't have an irq_desc array defined, so it cannot use the
generic irq_to_desc macro in the common header.
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
Release-Acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
RISCV declares irq_desc as a static array, opposed to x86 that uses a
pointer allocated at boot time. This creates issues when attempting to add
an extern declaration for irq_desc, as asm/irq.h is included by xen/irq.h where
the definition of struct irq_desc resides, and an empty forward declaration
doesn't make the compiler happy because it doesn't know the type
data-storage.
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
Release-Acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
When a node's depth exceeds DEVICE_TREE_MAX_DEPTH inside the
device_tree_for_each_node() loop, the code prints a warning and
executes 'continue;' statement, which jumps to condition check,
bypassing the iterator update step:
node = fdt_next_node(fdt, node, &depth).
The node and depth are not updated, the loop repeatedly evaluates
the same too-deep node, causing a hang.
Fix this by wrapping the node processing logic in an 'else' block.
This ensures the loop update step is executed on every iteration,
safely skipping deeply nested nodes and doing the traversal.
Fixes: 40f2ea3df2 ("xen/arm: pass node to device_tree_for_each_node")
Signed-off-by: Dmytro Prokopchuk <dmytro_prokopchuk1@epam.com>
Reviewed-by: Michal Orzel <michal.orzel@amd.com>
Release-Acked-by: Oleskii Kurochko <oleksii.kurochko@gmail.com>
gicv3_lpi_init_host_lpis() initializes Xen-side host LPI bookkeeping,
registers the CPU notifier, and allocates the boot CPU pending table.
The pending table allocation uses gicv3_its_get_memflags().
ITS quirks are discovered by gicv3_its_init(), so allocating the boot
CPU pending table from gicv3_dist_init() can happen before the memory
restrictions required by the ITS are known. On affected systems this
can leave the pending table allocated using the default memory policy.
Move host LPI initialization after gicv3_its_init(), and only run it
when a host ITS was found. The old call ignored the return value. Now
that the call is made from gicv3_init(), check it and panic on failure
because Redistributor LPI initialization relies on that state being
available.
Although this reorders host LPI bookkeeping with respect to ITS
initialization, it does not change the hardware-visible LPI setup
sequence. gicv3_lpi_init_host_lpis() does not program the
Redistributor or submit any ITS commands. gicv3_cpu_init() still
programs GICR_PENDBASER/GICR_PROPBASER via
gicv3_lpi_init_rdist(), sets GICR_CTLR.EnableLPIs, and only then calls
gicv3_its_setup_collection(), which submits the first MAPC/SYNC
commands. Therefore, the ordering introduced by 95604873cc remains
unchanged.
This also narrows the condition for host LPI initialization from
"GICD advertises LPIs" to "a host ITS was discovered". This is
intentional: Xen currently has no supported LPI path without a host
ITS, and gicv3_lpi_init_rdist() already rejects that case with
-ENODEV. Therefore, on systems where GICD_TYPE_LPIS is set but no host
ITS is present, skipping gicv3_lpi_init_host_lpis() only avoids
allocating host LPI state that cannot be used by a supported Xen LPI
path.
Fixes: dcb6cb2636 ("ARM: GICv3 ITS: introduce host LPI array")
Fixes: 751ec850ec ("ARM: ITS: implement quirks and add support for Renesas Gen4 ITS")
Signed-off-by: Mykola Kvach <mykola_kvach@epam.com>
Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Reviewed-by: Michal Orzel <michal.orzel@amd.com>
Release-Acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
Setting ->orig_video_isVGA to the specific marker should be done only when
the VBE tag is present and the FRAMEBUFFER is either absent or indicates
RGB type. Since the "video" variable now starts out non-NULL, this
property was broken when in particular neither of the tags are present. To
move back to at least close to original behavior, add a 2nd check to said
conditional.
Fixes: d5a73cdc6b ("x86/boot: Use boot_vid_info variable directly from C code")
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>
Reviewed-by: Teddy Astie <teddy.astie@vates.tech>
Release-Acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
XEN_DOMCTL_SCHEDOP_putvcpuinfo can flip the RTDS_extratime bit on a vCPU
that is currently depleted (cur_budget == 0, possibly sitting on the
depleted queue). rt_dom_cntl() touches only svc->flags; cur_budget is
left unchanged. As a result the next code path that calls runq_insert()
on this vCPU - rt_unit_wake() after a domain_unpause(),
rt_context_saved() following a delayed runq add, or repl_timer_handler()
after a replenishment - places the vCPU on the run queue, because
has_extratime(svc) is now true and runq_insert() admits extratime units
regardless of cur_budget:
/* add svc to runq if svc still has budget or its extratime is set */
if ( svc->cur_budget > 0 ||
has_extratime(svc) )
deadline_runq_insert(svc, &svc->q_elem, runq);
else
list_add(&svc->q_elem, &prv->depletedq);
The very next rt_schedule() iterates the run queue from runq_pick()
and trips the ASSERT(iter_svc->cur_budget > 0) at the bottom of the
loop, panicking the host. Observed trace:
Assertion 'iter_svc->cur_budget > 0' failed at common/sched/rt.c:1035
----[ Xen-4.22-unstable arm64 debug=y ubsan=y Not tainted ]----
[<...>] rt.c#rt_schedule+0x1558/0x33e0 (PC)
[<...>] core.c#do_schedule+0x2e4/0x15b4
[<...>] core.c#schedule+0xb14/0xe50
[<...>] softirq.c#__do_softirq+0x20c/0x3d4
[<...>] do_softirq+0x14/0x1c
[<...>] domain.c#idle_loop+0x194/0x558
Minimal reproducer: pin a single-vCPU domU to a pCPU, program RTDS with
extratime off and a low utilisation (e.g. budget = 10ms / period = 100ms)
so the vCPU spends most of its time in the depleted queue, pause the
domain, issue a putvcpuinfo that sets XEN_DOMCTL_SCHEDRT_extra, then
unpause. As soon as the schedule softirq fires on the pCPU, the BUG
hits. The same sequence is reachable without an explicit pause: any
window in which rt_dom_cntl() runs between burn_budget()'s budget
exhaustion and rt_context_saved()'s runq_insert() also closes onto the
same broken state, because the per-scheduler lock is dropped between
those two points.
The semantics for "extratime gets exhausted budget refilled" already
live in burn_budget():
if ( has_extratime(svc) )
{
svc->priority_level++;
svc->cur_budget = svc->budget;
}
Apply the same priority-demotion-and-refill in rt_dom_cntl() when the
flag transitions from off to on while the vCPU is depleted, clear
RTDS_depleted to match, and - if the vCPU is currently on the depleted
queue - move it to the run queue using the same q_remove() +
runq_insert() pattern already used by repl_timer_handler(). The vCPU
remains on the replenishment queue throughout, so its normal
replenishment cadence is preserved.
The complementary transition (on -> off) is already safe: clearing the
flag only narrows the runq_insert() admission condition, so subsequent
depleted insertions correctly route to the depleted queue.
No other call sites need changes: with cur_budget restored before the
flag is observable to runq_insert(), runq_pick()'s long-standing
invariant (every run-queue entry has cur_budget > 0) is preserved.
Fixes: 463b958317 ("xen:rtds: towards work conserving RTDS")
Signed-off-by: Oleksii Moisieiev <oleksii_moisieiev@epam.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Release-Acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
Returning from an NMI which hits guest context needs special casing in FRED
mode just like it does in IDT mode.
Break nmi_exit_to_guest() out of handle_ist_exception(), and use it in
entry_FRED_R3() also.
Expand the comment a little, and invert the conditional jump to
compat_restore_all_guest() to avoid needing an #else clause for CONFIG_PV32.
Fixes: 87cfcbe9f0 ("x86/pv: Guest exception handling in FRED mode")
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Relase-Acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
Loaders respecting IMAGE_SCN_MEM_DISCARDABLE would not load such sections,
yet we need to access it ourselves when switching out of "physical mode".
Leverage behavior new to GNU ld 2.46: Any contribution to .reloc which
doesn't have the discardable flag set (which cannot even be expressed in
ELF) will yield the output section also non-discardable.
Since for intermediate binaries we don't care about section attributes,
link in the new object only on the final linking pass.
Reported-by: Yann Sionneau <yann.sionneau@vates.tech>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Release-Acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
Prior to commit 9c20d3c591 ("x86/IDT: Make idt_tables[] be per_cpu(idt)"),
the global idt_tables[] was always safe to use for CPUs in any state.
However, not-yet-onlined CPUs (e.g. MADT with more entries than exist in
practice) or offlined CPUs (e.g. xen-hptool) have their per-cpu pointer
poisoned to detect incorrect uses. machine_kexec() trips over the posion when
clobbering #MC entry paths. Update the comment to discuss parked CPUs, and to
remove discussion which isn't particularly relevant to the actions at hand.
This fixes a fatal #GP (non-canonical memory reference) when trying to enter
the crash kernel.
Fixes: 9c20d3c591 ("x86/IDT: Make idt_tables[] be per_cpu(idt)")
Reported-by: Lin Liu <Lin.Liu01@citrix.com>
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Release-Acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
With FRED just as with IDT, it's unsafe to run the exception handlers after
switching stack.
To remove this unsafe window, %cr4 needs clearing earlier. In turn, we may
need to switch to PCID 0 earlier too in order to be able to clear CR4.PCIDE.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Release-Acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
---
CC: Jan Beulich <JBeulich@suse.com>
CC: Roger Pau Monné <roger.pau@citrix.com>
Jan Beulich