linux-stable.git/tools/testing, branch v6.18.33

selftests/bpf: Remove test_access_variable_array

2026-05-23T11:07:21+00:00

commit aacee214d57636fa1f63007c65f333b5ea75a7a0 upstream.

test_access_variable_array relied on accessing struct sched_domain::span
to validate variable-length array handling via BTF. Recent scheduler
refactoring removed or hid this field, causing the test
to fail to build.

Given that this test depends on internal scheduler structures that are
subject to refactoring, and equivalent variable-length array coverage
already exists via bpf_testmod-based tests, remove
test_access_variable_array entirely.

Link: https://lore.kernel.org/all/177434340048.1647592.8586759362906719839.tip-bot2@tip-bot2/

Signed-off-by: Venkat Rao Bagalkote 
Tested-by: Naveen Kumar Thummalapenta 
Link: https://lore.kernel.org/r/20260410105404.91126-1-venkat88@linux.ibm.com
Signed-off-by: Alexei Starovoitov 
Signed-off-by: Greg Kroah-Hartman

kselftest/arm64: Include for user_gcs definition

2026-05-23T11:07:14+00:00

[ Upstream commit bb7235e226888607e6aac1288062fcb1ac105589 ]

kselftest includes kernel uAPI headers with option:

  -isystem $(top_srcdir)/usr/include

Include  in libc-gcs.c for the definition of struct
user_gcs from the uAPI headers, and remove the redundant definition in
gcs-util.h. This fixes a compilation error on systems where the
toolchain defines NT_ARM_GCS.

Fixes: a505a52b4e29 ("kselftest/arm64: Add a GCS test program built with the system libc")
Signed-off-by: Leo Yan 
Reviewed-by: Mark Brown 
Signed-off-by: Catalin Marinas 
Signed-off-by: Sasha Levin

tcp: send a challenge ACK on SEG.ACK > SND.NXT

2026-05-23T11:07:05+00:00

[ Upstream commit 42726ec644cbdde0035c3e0417fee8ed9547e120 ]

RFC 5961 Section 5.2 validates an incoming segment's ACK value
against the range [SND.UNA - MAX.SND.WND, SND.NXT] and states:

  "All incoming segments whose ACK value doesn't satisfy the above
   condition MUST be discarded and an ACK sent back."

Commit 354e4aa391ed ("tcp: RFC 5961 5.2 Blind Data Injection Attack
Mitigation") opted Linux into this mitigation and implements the
challenge ACK on the lower side (SEG.ACK < SND.UNA - MAX.SND.WND),
but the symmetric upper side (SEG.ACK > SND.NXT) still takes the
pre-RFC-5961 path and silently returns
SKB_DROP_REASON_TCP_ACK_UNSENT_DATA, even though RFC 793 Section 3.9
(now RFC 9293 Section 3.10.7.4) has always required:

  "If the ACK acknowledges something not yet sent (SEG.ACK > SND.NXT)
   then send an ACK, drop the segment, and return."

Complete the mitigation by sending a challenge ACK on that branch,
reusing the existing tcp_send_challenge_ack() path which already
enforces the per-socket RFC 5961 Section 7 rate limit via
__tcp_oow_rate_limited().  FLAG_NO_CHALLENGE_ACK is honoured for
symmetry with the lower-edge case.

Update the existing tcp_ts_recent_invalid_ack.pkt selftest, which
drives this exact path, to consume the new challenge ACK.

Fixes: 354e4aa391ed ("tcp: RFC 5961 5.2 Blind Data Injection Attack Mitigation")
Signed-off-by: Jiayuan Chen 
Reviewed-by: Eric Dumazet 
Link: https://patch.msgid.link/20260422123605.320000-2-jiayuan.chen@linux.dev
Signed-off-by: Jakub Kicinski 
Signed-off-by: Sasha Levin

bpf: allow UTF-8 literals in bpf_bprintf_prepare()

2026-05-23T11:06:52+00:00

[ Upstream commit b960430ea8862ef37ce53c8bf74a8dc79d3f2404 ]

bpf_bprintf_prepare() only needs ASCII parsing for conversion
specifiers. Plain text can safely carry bytes >= 0x80, so allow
UTF-8 literals outside '%' sequences while keeping ASCII control
bytes rejected and format specifiers ASCII-only.

This keeps existing parsing rules for format directives unchanged,
while allowing helpers such as bpf_trace_printk() to emit UTF-8
literal text.

Update test_snprintf_negative() in the same commit so selftests keep
matching the new plain-text vs format-specifier split during bisection.

Fixes: 48cac3f4a96d ("bpf: Implement formatted output helpers with bstr_printf")
Signed-off-by: Yihan Ding 
Acked-by: Paul Chaignon 
Link: https://lore.kernel.org/r/20260416120142.1420646-2-dingyihan@uniontech.com
Signed-off-by: Alexei Starovoitov 
Signed-off-by: Sasha Levin

ktest: Run POST_KTEST hooks on failure and cancellation

2026-05-23T11:06:43+00:00

[ Upstream commit bc6e165a452da909cef0efbc286e6695624db372 ]

PRE_KTEST can be useful for setting up the environment and POST_KTEST to
tear it down, however POST_KTEST only runs on the normal end-of-run path.
It is skipped when ktest exits through dodie() or cancel_test(). Final
cleanup hooks are skipped.

Factor the final hook execution into run_post_ktest(), call it from the
normal exit path and from the early exit paths, and guard it so the hook
runs at most once.

Cc: John Hawley 
Cc: Andrea Righi 
Cc: Marcos Paulo de Souza 
Cc: Matthieu Baerts 
Cc: Fernando Fernandez Mancera 
Cc: Pedro Falcato 
Link: https://patch.msgid.link/20260307-ktest-fixes-v1-8-565d412f4925@suse.com
Fixes: 921ed4c7208e ("ktest: Add PRE/POST_KTEST and TEST options")
Signed-off-by: Ricardo B. Marlière 
Signed-off-by: Steven Rostedt 
Signed-off-by: Sasha Levin

ktest: Honor empty per-test option overrides

2026-05-23T11:06:43+00:00

[ Upstream commit a2de57a3c8192dcd67cccaff6c341b93748d799b ]

A per-test override can clear an inherited default option by assigning an
empty value, but __set_test_option() still used option_defined() to decide
whether a per-test key existed. That turned an empty per-test assignment
back into "fall back to the default", so tests still could not clear
inherited settings.

For example:

  DEFAULTS
  (...)
  LOG_FILE = /tmp/ktest-empty-override.log
  CLEAR_LOG = 1
  ADD_CONFIG = /tmp/.config

  TEST_START
  TEST_TYPE = build
  BUILD_TYPE = nobuild
  ADD_CONFIG =

This would run the test with ADD_CONFIG[1] = /tmp/.config

Fix by checking whether the per-test key exists before falling back. If it
does exist but is empty, treat it as unset for that test and stop the
fallback chain there.

Cc: John Hawley 
Cc: Andrea Righi 
Cc: Marcos Paulo de Souza 
Cc: Matthieu Baerts 
Cc: Fernando Fernandez Mancera 
Cc: Pedro Falcato 
Link: https://patch.msgid.link/20260307-ktest-fixes-v1-4-565d412f4925@suse.com
Fixes: 22c37a9ac49d ("ktest: Allow tests to undefine default options")
Signed-off-by: Ricardo B. Marlière 
Signed-off-by: Steven Rostedt 
Signed-off-by: Sasha Levin

ktest: Avoid undef warning when WARNINGS_FILE is unset

2026-05-23T11:06:43+00:00

[ Upstream commit 057854f8a595160656fe77ed7bf0d2403724b915 ]

check_buildlog() probes $warnings_file with -f even when WARNINGS_FILE is
not configured. Perl warns about the uninitialized value and adds noise to
the test log, which can hide the output we actually care about.

Check that WARNINGS_FILE is defined before testing whether the file exists.

Cc: John Hawley 
Cc: Andrea Righi 
Cc: Marcos Paulo de Souza 
Cc: Matthieu Baerts 
Cc: Fernando Fernandez Mancera 
Cc: Pedro Falcato 
Link: https://patch.msgid.link/20260307-ktest-fixes-v1-1-565d412f4925@suse.com
Fixes: 4283b169abfb ("ktest: Add make_warnings_file and process full warnings")
Signed-off-by: Ricardo B. Marlière 
Signed-off-by: Steven Rostedt 
Signed-off-by: Sasha Levin

selftest: memcg: skip memcg_sock test if address family not supported

2026-05-23T11:06:41+00:00

[ Upstream commit 2d028f3e4bbbfd448928a8d3d2814b0b04c214f4 ]

The test_memcg_sock test in memcontrol.c sets up an IPv6 socket and send
data over it to consume memory and verify that memory.stat.sock and
memory.current values are close.

On systems where IPv6 isn't enabled or not configured to support
SOCK_STREAM, the test_memcg_sock test always fails.  When the socket()
call fails, there is no way we can test the memory consumption and verify
the above claim.  I believe it is better to just skip the test in this
case instead of reporting a test failure hinting that there may be
something wrong with the memcg code.

Link: https://lkml.kernel.org/r/20260311200526.885899-1-longman@redhat.com
Fixes: 5f8f019380b8 ("selftests: cgroup/memcontrol: add basic test for socket accounting")
Signed-off-by: Waiman Long 
Acked-by: Michal Koutný 
Acked-by: Shakeel Butt 
Cc: Johannes Weiner 
Cc: Michal Hocko 
Cc: Michal Koutný 
Cc: Mike Rapoport 
Cc: Muchun Song 
Cc: Roman Gushchin 
Cc: Shuah Khan 
Cc: Tejun Heo 
Signed-off-by: Andrew Morton 
Signed-off-by: Sasha Levin

kho: make debugfs interface optional

2026-05-23T11:06:41+00:00

[ Upstream commit 03d3963464a43654703938a66503cd686c5fc54e ]

Patch series "liveupdate: Rework KHO for in-kernel users", v9.

This series refactors the KHO framework to better support in-kernel users
like the upcoming LUO.  The current design, which relies on a notifier
chain and debugfs for control, is too restrictive for direct programmatic
use.

The core of this rework is the removal of the notifier chain in favor of a
direct registration API.  This decouples clients from the shutdown-time
finalization sequence, allowing them to manage their preserved state more
flexibly and at any time.

In support of this new model, this series also:
 - Makes the debugfs interface optional.
 - Introduces APIs to unpreserve memory and fixes a bug in the abort
   path where client state was being incorrectly discarded. Note that
   this is an interim step, as a more comprehensive fix is planned as
   part of the stateless KHO work [1].
 - Moves all KHO code into a new kernel/liveupdate/ directory to
   consolidate live update components.

This patch (of 9):

Currently, KHO is controlled via debugfs interface, but once LUO is
introduced, it can control KHO, and the debug interface becomes optional.

Add a separate config CONFIG_KEXEC_HANDOVER_DEBUGFS that enables the
debugfs interface, and allows to inspect the tree.

Move all debugfs related code to a new file to keep the .c files clear of
ifdefs.

Link: https://lkml.kernel.org/r/20251101142325.1326536-1-pasha.tatashin@soleen.com
Link: https://lkml.kernel.org/r/20251101142325.1326536-2-pasha.tatashin@soleen.com
Link: https://lore.kernel.org/all/20251020100306.2709352-1-jasonmiu@google.com [1]
Co-developed-by: Mike Rapoport (Microsoft) 
Signed-off-by: Mike Rapoport (Microsoft) 
Signed-off-by: Pasha Tatashin 
Reviewed-by: Pratyush Yadav 
Cc: Alexander Graf 
Cc: Christian Brauner 
Cc: Jason Gunthorpe 
Cc: Jonathan Corbet 
Cc: Masahiro Yamada 
Cc: Miguel Ojeda 
Cc: Randy Dunlap 
Cc: Tejun Heo 
Cc: Changyuan Lyu 
Cc: Jason Gunthorpe 
Cc: Simon Horman 
Cc: Zhu Yanjun 
Signed-off-by: Andrew Morton 
Stable-dep-of: 019fc3687237 ("kho: fix KASAN support for restored vmalloc regions")
Signed-off-by: Sasha Levin

selftests/mm: skip migration tests if NUMA is unavailable

2026-05-23T11:06:41+00:00

[ Upstream commit 54218f10dfbe88c8e41c744fd45a756cde60b8c4 ]

Currently, the migration test asserts that numa_available() returns 0.  On
systems where NUMA is not available (returning -1), such as certain ARM64
configurations or single-node systems, this assertion fails and crashes
the test.

Update the test to check the return value of numa_available().  If it is
less than 0, skip the test gracefully instead of failing.

This aligns the behavior with other MM selftests (like rmap) that skip
when NUMA support is missing.

Link: https://lkml.kernel.org/r/20260218163941.13499-1-anishm7030@gmail.com
Fixes: 0c2d08728470 ("mm: add selftests for migration entries")
Signed-off-by: AnishMulay 
Reviewed-by: SeongJae Park 
Reviewed-by: Dev Jain 
Reviewed-by: Anshuman Khandual 
Tested-by: Sayali Patil 
Acked-by: David Hildenbrand (Arm) 
Cc: Liam Howlett 
Cc: Lorenzo Stoakes 
Cc: Michal Hocko 
Cc: Mike Rapoport 
Cc: Shuah Khan 
Cc: Suren Baghdasaryan 
Cc: Vlastimil Babka 
Signed-off-by: Andrew Morton 
Signed-off-by: Sasha Levin