aboutsummaryrefslogtreecommitdiff
path: root/lib
AgeCommit message (Collapse)AuthorFilesLines
9 daysvdso/datastore: Mark vdso_k_*_data pointers as __ro_after_initThomas Weißschuh1-3/+3
These pointers are only modified once in vdso_setup_data_pages(), during the init phase. Make them read-only after that. Drop __refdata as that would conflict with __ro_after_init. Modpost does accept the reference from a __ro_after_init symbol to an __init one. Fixes: 05988dba1179 ("vdso/datastore: Allocate data pages dynamically") Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@kernel.org> Link: https://patch.msgid.link/20260513-vdso-ro-after-init-v1-1-4b51f74015a4@linutronix.de
13 daysMerge tag 'iommu-fixes-v7.1-rc5' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/iommu/linux Pull iommu fixes from Joerg Roedel: - Fix compile warning with gcc-16.1 - Intel VT-d: Simplify calculate_psi_aligned_address() - MAINTAINERS updates * tag 'iommu-fixes-v7.1-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/iommu/linux: MAINTAINERS: Add my employer to my entries MAINTAINERS: Add Vasant Hegde to reviewers of AMD IOMMU iommu, debugobjects: avoid gcc-16.1 section mismatch warnings iommu/vt-d: Simplify calculate_psi_aligned_address()
2026-05-28iommu, debugobjects: avoid gcc-16.1 section mismatch warningsArnd Bergmann1-1/+1
gcc-16 has gained some more advanced inter-procedual optimization techniques that enable it to inline the dummy_tlb_add_page() and dummy_tlb_flush() function pointers into a specialized version of __arm_v7s_unmap: WARNING: modpost: vmlinux: section mismatch in reference: __arm_v7s_unmap+0x2cc (section: .text) -> dummy_tlb_add_page (section: .init.text) ERROR: modpost: Section mismatches detected. >From what I can tell, the transformation is correct, as this is only called when __arm_v7s_unmap() is called from arm_v7s_do_selftests(), which is also __init. Since __arm_v7s_unmap() however is not __init, gcc cannot inline the inner function calls directly. In debug_objects_selftest(), the same thing happens. Both the caller and the leaf function are __init, but the IPA pulls it into a non-init one: WARNING: modpost: vmlinux: section mismatch in reference: lookup_object_or_alloc+0x7c (section: .text.lookup_object_or_alloc) -> is_static_object (section: .init.text) Marking the affected functions as not "__init" would reliably avoid this issue but is not a good solution because it removes an otherwise correct annotation. I tried marking the functions as 'noinline', but that ended up not covering all the affected configurations. With some more experimenting, I found that marking these functions as __attribute__((noipa)) is both logical and reliable. In order to keep the syntax readable, add a custom macro for this in include/linux/compiler_attributes.h next to other related macros and use it to annotate both files. Link: https://lore.kernel.org/all/abRB6g-48ZX6Yl2r@willie-the-truck/ Cc: Will Deacon <will@kernel.org> Cc: Thomas Gleixner <tglx@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Miguel Ojeda <ojeda@kernel.org> Cc: linux-kbuild@vger.kernel.org Cc: stable@vger.kernel.org Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Will Deacon <will@kernel.org> Acked-by: Thomas Gleixner <tglx@kernel.org> Acked-by: Miguel Ojeda <ojeda@kernel.org> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2026-05-26Merge tag 'linux_kselftest-kunit-fixes-7.1-rc6' of ↵Linus Torvalds2-3/+17
git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest Pull kunit fix from Shuah Khan: "Fix a use-after-free in kunit debugfs when using kunit.filter when the executor frees dynamically allocated resources after running boot-time tests. This resulted in fatal hardware exception due to invalidation of capability flags on the reclaimed memory on some architectures such as CHERI RISC-V that support the feature, and silent memory corruption on others. The fix for this couples the lifetime of the filtered suite memory allocation to the lifetime of the kunit subsystem and its associated VFS nodes. Ownership of the boot-time suite_set is now transferred to a global tracker ('kunit_boot_suites'), and the memory is cleanly released in kunit_exit() during module teardown" * tag 'linux_kselftest-kunit-fixes-7.1-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: kunit: fix use-after-free in debugfs when using kunit.filter
2026-05-24Merge tag 'core-urgent-2026-05-24' of ↵Linus Torvalds1-4/+14
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull debugobjects fix from Ingo Molnar:: - Fix debugobjects regression on -rt kernels: don't fill the pool (which uses a coarse lock) if ->pi_blocked_on, because that messes up the priority inheritance of callers * tag 'core-urgent-2026-05-24' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: debugobjects: Do not fill_pool() if pi_blocked_on
2026-05-21kunit: fix use-after-free in debugfs when using kunit.filterFlorian Schmaus2-3/+17
When the kernel is booted with a kunit filter (e.g., kunit.filter="speed!=slow"), the kunit executor dynamically allocates copies of the filtered test suites using kmalloc/kmemdup. During the initial boot execution, kunit_debugfs_create_suite() creates debugfs files (such as /sys/kernel/debug/kunit/<suite>/run) and permanently stores a pointer to the dynamically allocated suite in the inode's i_private field. Previously, the executor freed this dynamically allocated suite_set immediately after executing the boot-time tests. Because the debugfs nodes were not destroyed, any subsequent interaction with the debugfs `run` file from userspace triggered a use-after-free (UAF). On systems with architectural capabilities, like CHERI RISC-V, this resulted in an immediate fatal hardware exception due to the invalidation of the capability tags on the reclaimed memory. On other architectures, it resulted in silent memory corruption. Fix this UAF by properly coupling the lifetime of the filtered suite memory allocation to the lifetime of the kunit subsystem and its associated VFS nodes. Ownership of the boot-time suite_set is now transferred to a global tracker ('kunit_boot_suites'), and the memory is cleanly released in kunit_exit() during module teardown. Link: https://lore.kernel.org/r/20260507084854.233984-1-florian.schmaus@codasip.com Fixes: e2219db280e3 ("kunit: add debugfs /sys/kernel/debug/kunit/<suite>/results display") Signed-off-by: Florian Schmaus <florian.schmaus@codasip.com> Reviewed-by: Martin Kaiser <martin@kaiser.cx> Reviewed-by: David Gow <david@davidgow.net> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2026-05-19Merge tag 'mm-hotfixes-stable-2026-05-18-21-07' of ↵Linus Torvalds1-5/+5
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull misc fixes from Andrew Morton: "14 hotfixes. 9 are for MM. 10 are cc:stable and the remainder are for post-7.1 issues or aren't deemed suitable for backporting. There's a two-patch MAINTAINERS series from Mike Rapoport which updates us for the new KEXEC/KDUMP/crash/LUO/etc arrangements. And another two-patch series from Muchun Song to fix a couple of memory-hotplug issues. Otherwise singletons, please see the changelogs for details" * tag 'mm-hotfixes-stable-2026-05-18-21-07' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: mm/memory: fix spurious warning when unmapping device-private/exclusive pages mm: fix __vm_normal_page() to handle missing support for pmd_special()/pud_special() drivers/base/memory: fix memory block reference leak in poison accounting mm/memory_hotplug: fix memory block reference leak on remove lib: kunit_iov_iter: fix test fail on powerpc mm/page_alloc: fix initialization of tags of the huge zero folio with init_on_free MAINTAINERS: add kexec@ list to LIVE UPDATE ENTRY MAINTAINERS: add tree for KDUMP and KEXEC selftests/mm: run_vmtests.sh: fix destructive tests invocation scripts/gdb: slab: update field names of struct kmem_cache scripts/gdb: mm: cast untyped symbols in x86_page_ops mm/damon: fix damos_stat tracepoint format for sz_applied mm/damon/sysfs-schemes: call missing mem_cgroup_iter_break() mm/migrate_device: fix spinlock leak in migrate_vma_insert_huge_pmd_page
2026-05-18debugobjects: Do not fill_pool() if pi_blocked_onHelen Koike1-4/+14
On RT enabled kernels, fill_pool() ends up calling rtlock_lock(), which asserts if current::pi_blocked_on is set, because a task can obviously only block on one lock as otherwise the priority inheritenace chain gets corrupted. Prevent this by expanding the conditional to take current::pi_blocked_on into account. Fixes: 4bedcc28469a ("debugobjects: Make them PREEMPT_RT aware") Reported-by: syzbot+b8ca586b9fc235f0c0df@syzkaller.appspotmail.com Signed-off-by: Helen Koike <koike@igalia.com> Signed-off-by: Thomas Gleixner <tglx@kernel.org> Link: https://patch.msgid.link/20260511215359.3351259-1-koike@igalia.com Closes: https://syzkaller.appspot.com/bug?extid=b8ca586b9fc235f0c0df
2026-05-17Merge tag 'timers-urgent-2026-05-17' of ↵Linus Torvalds1-3/+2
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fix from Ingo Molnar: - Fix potential garbage reads in the vDSO gettimeofday code (Thomas Weißschuh) * tag 'timers-urgent-2026-05-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: vdso/gettimeofday: Reload sequence counter after switch to time page in do_aux()
2026-05-15Merge tag 'v7.1-p4' of ↵Linus Torvalds1-7/+26
git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 Pull crypto fixes from Herbert Xu: - Fix potential dead-lock in rhashtable when used by xattr - Avoid calling kvfree on atomic path in rhashtable * tag 'v7.1-p4' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: rhashtable: Add bucket_table_free_atomic() helper mm/slab: Add kvfree_atomic() helper rhashtable: drop ht->mutex in rhashtable_free_and_destroy()
2026-05-14vdso/gettimeofday: Reload sequence counter after switch to time page in do_aux()Thomas Weißschuh1-3/+2
After switching to the real data pages, the sequence counter needs to be reloaded from there. The code using vdso_read_begin_timens() assumed this worked by 'continue' jumping to the *beginning* of the do-while retry loop. However the 'continue' jumps to the *end* of said loop, evaluating the exit condition. If the data page has a sequence counter of '1' it will match the one from the time namespace page and prematurely exit the retry loop. This would result in garbage returned to the caller. Reload the sequence counter after switching the pages by using an inner while loop again, which will loop at most once. The loop generates slightly better code than an explicit reload through 'seq = vdso_read_begin()'. Fixes: ed78b7b2c5ae ("vdso/gettimeofday: Add a helper to read the sequence lock of a time namespace aware clock") Reported-by: Ricardo Ribalda <ribalda@chromium.org> Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@kernel.org> Tested-by: Ricardo Ribalda <ribalda@chromium.org> Reviewed-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org> Link: https://patch.msgid.link/20260422-vdso-aux-timens-loop-v1-1-e2dd8c7164cc@linutronix.de Closes: https://lore.kernel.org/lkml/CANiDSCsOy0P1if-gJZqOM5pTJ0RDcwVfru1B7KFbTOEMqjPKJw@mail.gmail.com/
2026-05-13lib: kunit_iov_iter: fix test fail on powerpcChristian A. Ehrhardt1-5/+5
Increase buffer size to accommodate machines with 64K PAGE_SIZE. Link: https://lore.kernel.org/20260421070707.992873-1-lk@c--e.de Fixes: 0913b7554726 ("lib: kunit_iov_iter: add tests for extract_iter_to_sg") Signed-off-by: Christian A. Ehrhardt <lk@c--e.de> Reported-by: David Gow <davidgow@google.com> Closes: https://lore.kernel.org/34a81ec2-af84-465d-9b5e-7bb5bf01680f@davidgow.net Tested-by: David Gow <davidgow@google.com> Tested-by: Josh Law <joshlaw48@gmail.com> Reviewed-by: Josh Law <joshlaw48@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-05-12Merge tag 'probes-fixes-v7.1-rc3' of ↵Linus Torvalds1-11/+18
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull probes fixes from Masami Hiramatsu: - kprobes: skip non-symbol addresses in kprobe_add_ksym_blacklist() Since the ftrace adds its NOPs at .kprobes.text section (which stores an array), a wrong entry is added when loading a module which uses "__kprobes" attribute. To solve this, add "notrace" to __kprobes functions - test_kprobes: clear kprobes between test runs Clear all kprobes in the test program after running a test set, because Kunit test can run several times - fprobe: Fix unregister_fprobe() to wait for RCU grace period Since the fprobe data structure is removed with hlist_del_rcu(), it should wait for the RCU grace period. If the caller waits for RCU, we can use the async variant (e.g. eBPF) * tag 'probes-fixes-v7.1-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: fprobe: Fix unregister_fprobe() to wait for RCU grace period test_kprobes: clear kprobes between test runs kprobes: skip non-symbol addresses in kprobe_add_ksym_blacklist()
2026-05-11Merge tag 'linux_kselftest-kunit-fixes-7.1-rc4' of ↵Linus Torvalds1-2/+3
git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest Pull kunit fixes from Shuah Khan: "Fix to decouple KUNIT_DEBUGFS and KUNIT_ALL_TESTS options and fix KUNIT_DEBUGFS dependencies so it depends on DEBUG_FS without which it will not be useful" * tag 'linux_kselftest-kunit-fixes-7.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: kunit: config: KUNIT_DEBUGFS should depend on DEBUG_FS kunit: config: Enable KUNIT_DEBUGFS by default
2026-05-08test_kprobes: clear kprobes between test runsMartin Kaiser1-11/+18
Running the kprobes sanity tests twice makes all tests fail and eventually crashes the kernel. [root@martin-riscv-1 ~]# echo 1 > /sys/kernel/debug/kunit/kprobes_test/run ... # Totals: pass:5 fail:0 skip:0 total:5 ok 1 kprobes_test [root@martin-riscv-1 ~]# echo 1 > /sys/kernel/debug/kunit/kprobes_test/run ... # test_kprobe: EXPECTATION FAILED at lib/tests/test_kprobes.c:64 Expected 0 == register_kprobe(&kp), but register_kprobe(&kp) == -22 (0xffffffffffffffea) ... Unable to handle kernel paging request ... The testsuite defines several kprobes and kretprobes as static variables that are preserved across test runs. After register_kprobe and unregister_kprobe, a kprobe contains some leftover data that must be cleared before the kprobe can be registered again. The tests are setting symbol_name to define the probe location. Address and flags must be cleared. The existing code clears some of the probes between subsequent tests, but not between two test runs. The leftover data from a previous test run makes the registrations fail in the next run. Move the cleanups for all kprobes into kprobes_test_init, this function is called before each single test (including the first test of a test run). Link: https://lore.kernel.org/all/20260507134615.1010905-1-martin@kaiser.cx/ Fixes: e44e81c5b90f ("kprobes: convert tests to kunit") Signed-off-by: Martin Kaiser <martin@kaiser.cx> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-05-05Merge tag 'fbdev-for-7.1-rc3' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/deller/linux-fbdev Pull fbdev fixes from Helge Deller: "Four small patches for fbdev, of which two are important: One fixes the bitmap font generation and the other prevents a possible use-after-free in udlfb: - Fix rotating fonts by 180 degrees (Thomas Zimmermann) - Drop duplicate include of linux/module.h in fb_defio (Chen Ni) - Add vm_ops in udlfb to prevent use-after-free (Rajat Gupta) - ipu-v3: clean up kernel-doc warnings (Randy Dunlap)" * tag 'fbdev-for-7.1-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/linux-fbdev: fbdev: udlfb: add vm_ops to dlfb_ops_mmap to prevent use-after-free lib/fonts: Fix bit position when rotating by 180 degrees fbdev: defio: Remove duplicate include of linux/module.h fbdev: ipu-v3: clean up kernel-doc warnings
2026-05-05rhashtable: Add bucket_table_free_atomic() helperUladzislau Rezki (Sony)1-1/+9
rhashtable_insert_rehash() allocates a new bucket table with GFP_ATOMIC, as it is called from an RCU read-side critical section. If rhashtable_rehash_attach() then fails, the new table is freed via kvfree(). This is unsafe, since kvfree() may fall back to vfree() for vmalloc-backed allocations, which can sleep and trigger: BUG: sleeping function called from invalid context Add bucket_table_free_atomic(), which uses kvfree_atomic() so the table can be freed safely from non-sleeping context. Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2026-05-05rhashtable: drop ht->mutex in rhashtable_free_and_destroy()Mikhail Gavrilov1-6/+17
rhashtable_free_and_destroy() is a single-shot teardown routine: cancel_work_sync() has already quiesced the deferred rehash worker, and the function's documented contract requires the caller to guarantee no other concurrent access to the rhashtable. Under those conditions ht->mutex is not protecting anything -- taking it is a leftover from the original teardown path. That leftover is actively harmful: it closes a circular lock-class dependency with fs_reclaim. The deferred rehash worker takes ht->mutex and then allocates GFP_KERNEL memory in bucket_table_alloc(), establishing &ht->mutex -> fs_reclaim After commit b32c4a213698 ("xattr: add rhashtable-based simple_xattr infrastructure") introduced simple_xattr_ht_free(), which calls rhashtable_free_and_destroy(), the simple_xattrs teardown became reachable from evict() under the dcache shrinker. The subsequent per-subsystem adaptations made the reverse edge concrete in three independent code paths: * commit 52b364fed6e1 ("shmem: adapt to rhashtable-based simple_xattrs with lazy allocation") * commit 5bd97f5c5f24 ("kernfs: adapt to rhashtable-based simple_xattrs with lazy allocation") * commit 50704c391fbf ("pidfs: adapt to rhashtable-based simple_xattrs") Any of the three closes the cycle fs_reclaim -> &ht->mutex which lockdep reports as follows. This particular splat was observed organically on a workstation kernel built from vfs-7.1-rc1.xattr at ~35h uptime under normal mixed workload, with CONFIG_PROVE_LOCKING=y. The path happens to go through kernfs: WARNING: possible circular locking dependency detected 7.0.0-faeab166167f-with-fixes-v1+ #191 Tainted: G U kswapd0/243 is trying to acquire lock: ffff8882e475c0f8 (&ht->mutex){+.+.}-{4:4}, at: rhashtable_free_and_destroy+0x36/0x740 but task is already holding lock: ffffffffa8ad1d00 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat+0x995/0x1600 the existing dependency chain (in reverse order) is: -> #1 (fs_reclaim){+.+.}-{0:0}: __lock_acquire+0x506/0xbf0 lock_acquire.part.0+0xc7/0x280 fs_reclaim_acquire+0xd9/0x130 __kvmalloc_node_noprof+0xcd/0xb40 bucket_table_alloc.isra.0+0x5a/0x440 rhashtable_rehash_alloc+0x4e/0xd0 rht_deferred_worker+0x14b/0x440 process_one_work+0x8fd/0x16a0 worker_thread+0x601/0xff0 kthread+0x36b/0x470 ret_from_fork+0x5bf/0x910 ret_from_fork_asm+0x1a/0x30 -> #0 (&ht->mutex){+.+.}-{4:4}: check_prev_add+0xdb/0xce0 validate_chain+0x554/0x780 __lock_acquire+0x506/0xbf0 lock_acquire.part.0+0xc7/0x280 __mutex_lock+0x1b2/0x2550 rhashtable_free_and_destroy+0x36/0x740 kernfs_put.part.0+0x119/0x570 evict+0x3b6/0x9c0 __dentry_kill+0x181/0x540 shrink_dentry_list+0x135/0x440 prune_dcache_sb+0xdb/0x150 super_cache_scan+0x2ff/0x520 do_shrink_slab+0x35a/0xee0 shrink_slab_memcg+0x457/0x950 shrink_slab+0x43b/0x550 shrink_one+0x31a/0x6f0 shrink_many+0x31e/0xc80 shrink_node+0xeb3/0x14a0 balance_pgdat+0x8ed/0x1600 kswapd+0x2f3/0x530 kthread+0x36b/0x470 ret_from_fork+0x5bf/0x910 ret_from_fork_asm+0x1a/0x30 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(fs_reclaim); lock(&ht->mutex); lock(fs_reclaim); lock(&ht->mutex); Note that lockdep tracks lock classes, not instances: the two &ht->mutex sites are on different rhashtable objects (the deferred worker was triggered by some unrelated rhashtable growth), but because rhashtable_init() uses a single static lockdep key for all rhashtables, this is a real class-level cycle. Once reported, lockdep disables itself for the remainder of the boot, masking any subsequent locking bugs. Drop the mutex. After cancel_work_sync() the rehash worker is quiesced and, per this function's contract, no other concurrent access is possible; the tables are therefore owned exclusively by this function and can be walked without any lock held. Switch the table walks from rht_dereference() (which requires ht->mutex to be held under CONFIG_PROVE_RCU) to rcu_dereference_raw(), which has no lockdep annotation. rht_ptr_exclusive() already uses rcu_dereference_protected(p, 1) and needs no change. This is the only place in lib/rhashtable.c where &ht->mutex is acquired from a path reachable under fs_reclaim; the deferred worker is the only other site and it is the forward edge. Removing the acquisition here therefore eliminates the class cycle for all three subsystems that use simple_xattrs, not just the one in the splat above. No locking-semantics change is introduced for correct users; incorrect users would already be racing with rehash worker completion regardless of the mutex. Synthetic reproduction of the splat within a few-minute window was unsuccessful across several attempts (tmpfs and kernfs zombies via cgroupfs with open-fd-through-rmdir, with and without swap, up to ~60k reclaim-path executions of simple_xattr_ht_free() in a single run), consistent with the rare coincidence-of-edges profile of the bug: the forward edge is already registered in /proc/lockdep on any idle system via rht_deferred_worker, but the reverse edge requires evict() to complete kernfs_put()'s final release inside the fs_reclaim critical section, which in my attempts was ordered against rather than interleaved with the worker. Fixes: b32c4a213698 ("xattr: add rhashtable-based simple_xattr infrastructure") Signed-off-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2026-05-04kunit: config: KUNIT_DEBUGFS should depend on DEBUG_FSDavid Gow1-0/+1
CONFIG_KUNIT_DEBUGFS is totally useless without debugfs, so it should depend on CONFIG_DEBUG_FS. Link: https://lore.kernel.org/r/20260425034155.53913-2-david@davidgow.net Fixes: e2219db280e3 ("kunit: add debugfs /sys/kernel/debug/kunit/<suite>/results display") Signed-off-by: David Gow <david@davidgow.net> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2026-05-04kunit: config: Enable KUNIT_DEBUGFS by defaultDavid Gow1-2/+2
The KUNIT_DEBUGFS option is currently enabled based on the value of KUNIT_ALL_TESTS, but it really doesn't have anything to do with the set of enabled tests, so just enable it by default anyway. In particular, this shouldn't be only visible if KUNIT_ALL_TESTS is set, which is quite confusing. Link: https://lore.kernel.org/r/20260425034155.53913-1-david@davidgow.net Fixes: beaed42c427d ("kunit: default KUNIT_* fragments to KUNIT_ALL_TESTS") Signed-off-by: David Gow <david@davidgow.net> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2026-05-01Merge tag 'mm-hotfixes-stable-2026-04-30-15-39' of ↵Linus Torvalds2-3/+3
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM fixes from Andrew Morton: "20 hotfixes. All are for MM (and for MMish maintainers). 9 are cc:stable and the remainder are for post-7.0 issues or aren't deemed suitable for backporting. There are two DAMON series from SeongJae Park which address races which could lead to use-after-free errors, and avoid the possibility of presenting stale parameter values to users" * tag 'mm-hotfixes-stable-2026-04-30-15-39' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: mm: memcontrol: fix rcu unbalance in get_non_dying_memcg_end() mm/userfaultfd: detect VMA type change after copy retry in mfill_copy_folio_retry() MAINTAINERS: remove stale kdump project URL mm/damon/stat: detect and use fresh enabled value mm/damon/lru_sort: detect and use fresh enabled and kdamond_pid values mm/damon/reclaim: detect and use fresh enabled and kdamond_pid values selftests/mm: specify requirement for PROC_MEM_ALWAYS_FORCE=y mm/damon/sysfs-schemes: protect path kfree() with damon_sysfs_lock mm/damon/sysfs-schemes: protect memcg_path kfree() with damon_sysfs_lock MAINTAINERS: update Li Wang's email address MAINTAINERS, mailmap: update email address for Qi Zheng MAINTAINERS: update Liam's email address mm/hugetlb_cma: round up per_node before logging it MAINTAINERS: fix regex pattern in CORE MM category mm/vma: do not try to unmap a VMA if mmap_prepare() invoked from mmap() mm: start background writeback based on per-wb threshold for strictlimit BDIs kho: fix error handling in kho_add_subtree() liveupdate: fix return value on session allocation failure mailmap: update entry for Dan Carpenter vmalloc: fix buffer overflow in vrealloc_node_align()
2026-04-28Merge tag 'sched_ext-for-7.1-rc1-fixes' of ↵Linus Torvalds1-5/+31
git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext Pull sched_ext fixes from Tejun Heo: "The merge window pulled in the cgroup sub-scheduler infrastructure, and new AI reviews are accelerating bug reporting and fixing - hence the larger than usual fixes batch: - Use-after-frees during scheduler load/unload: - The disable path could free the BPF scheduler while deferred irq_work / kthread work was still in flight - cgroup setter callbacks read the active scheduler outside the rwsem that synchronizes against teardown Fix both, and reuse the disable drain in the enable error paths so the BPF JIT page can't be freed under live callbacks. - Several BPF op invocations didn't tell the framework which runqueue was already locked, so helper kfuncs that re-acquire the runqueue by CPU could deadlock on the held lock Fix the affected callsites, including recursive parent-into-child dispatch. - The hardlockup notifier ran from NMI but eventually took a non-NMI-safe lock. Bounce it through irq_work. - A handful of bugs in the new sub-scheduler hierarchy: - helper kfuncs hard-coded the root instead of resolving the caller's scheduler - the enable error path tried to disable per-task state that had never been initialized, and leaked cpus_read_lock on the way out - a sysfs object was leaked on every load/unload - the dispatch fast-path used the root scheduler instead of the task's - a couple of CONFIG #ifdef guards were misclassified - Verifier-time hardening: BPF programs of unrelated struct_ops types (e.g. tcp_congestion_ops) could call sched_ext kfuncs - a semantic bug and, once sub-sched was enabled, a KASAN out-of-bounds read. Now rejected at load. Plus a few NULL and cross-task argument checks on sched_ext kfuncs, and a selftest covering the new deny. - rhashtable (Herbert): restore the insecure_elasticity toggle and bounce the deferred-resize kick through irq_work to break a lock-order cycle observable from raw-spinlock callers. sched_ext's scheduler-instance hash is the first user of both. - The bypass-mode load balancer used file-scope cpumasks; with multiple scheduler instances now possible, those raced. Move to per-instance cpumasks, plus a follow-up to skip tasks whose recorded CPU is stale relative to the new owning runqueue. - Smaller fixes: - a dispatch queue's first-task tracking misbehaved when a parked iterator cursor sat in the list - the runqueue's next-class wasn't promoted on local-queue enqueue, leaving an SCX task behind RT in edge cases - the reference qmap scheduler stopped erroring on legitimate cross-scheduler task-storage misses" * tag 'sched_ext-for-7.1-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext: (26 commits) sched_ext: Fix scx_flush_disable_work() UAF race sched_ext: Call wakeup_preempt() in local_dsq_post_enq() sched_ext: Release cpus_read_lock on scx_link_sched() failure in root enable sched_ext: Reject NULL-sch callers in scx_bpf_task_set_slice/dsq_vtime sched_ext: Refuse cross-task select_cpu_from_kfunc calls sched_ext: Align cgroup #ifdef guards with SUB_SCHED vs GROUP_SCHED sched_ext: Make bypass LB cpumasks per-scheduler sched_ext: Pass held rq to SCX_CALL_OP() for core_sched_before sched_ext: Pass held rq to SCX_CALL_OP() for dump_cpu/dump_task sched_ext: Save and restore scx_locked_rq across SCX_CALL_OP sched_ext: Use dsq->first_task instead of list_empty() in dispatch_enqueue() FIFO-tail sched_ext: Resolve caller's scheduler in scx_bpf_destroy_dsq() / scx_bpf_dsq_nr_queued() sched_ext: Read scx_root under scx_cgroup_ops_rwsem in cgroup setters sched_ext: Don't disable tasks in scx_sub_enable_workfn() abort path sched_ext: Skip tasks with stale task_rq in bypass_lb_cpu() sched_ext: Guard scx_dsq_move() against NULL kit->dsq after failed iter_new sched_ext: Unregister sub_kset on scheduler disable sched_ext: Defer scx_hardlockup() out of NMI sched_ext: sync disable_irq_work in bpf_scx_unreg() sched_ext: Fix local_dsq_post_enq() to use task's scheduler in sub-sched ...
2026-04-28lib/fonts: Fix bit position when rotating by 180 degreesThomas Zimmermann1-1/+1
Fix the horizontal bit position when rotating a glyph by 180°. The original code in rotate_ud() rounded the value in width up to a multiple of 8, aka the bit pitch, and calculated the rotated pixel from that value. The new code stores the glyph's pitch in bit_pitch, but fails to update the rotated pixel's output accordingly. Simply replacing the variable does this. The bug can be reproduced by setting a font with an unaligned width, such as sun12x22, like this: setfont sun12x22 echo 2 > /sys/class/graphics/fbcon/rotate Without the fix, the font looks distorted. Fixes: a30e9e6b018f ("lib/fonts: Refactor glyph-rotation helpers") Closes: https://lore.gitlab.freedesktop.org/drm-ai-reviews/review-patch7-20260407092555.58816-8-tzimmermann@suse.de/ Cc: dri-devel@lists.freedesktop.org Cc: linux-fbdev@vger.kernel.org Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Signed-off-by: Helge Deller <deller@gmx.de>
2026-04-27MAINTAINERS: update Liam's email addressLiam R. Howlett2-3/+3
Switching to private email address. Update all contact information Add an entry to mailmap at the same time. Link: https://lore.kernel.org/20260422184310.2682901-1-liam@infradead.org Signed-off-by: Liam R. Howlett <liam@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-24Merge tag 'riscv-for-linus-7.1-mw1' of ↵Linus Torvalds2-0/+285
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V updates from Paul Walmsley: "There is one significant change outside arch/riscv in this pull request: the addition of a set of KUnit tests for strlen(), strnlen(), and strrchr(). Otherwise, the most notable changes are to add some RISC-V-specific string function implementations, to remove XIP kernel support, to add hardware error exception handling, and to optimize our runtime unaligned access speed testing. A few comments on the motivation for removing XIP support. It's been broken in the RISC-V kernel for months. The code is not easy to maintain. Furthermore, for XIP support to truly be useful for RISC-V, we think that compile-time feature switches would need to be added for many of the RISC-V ISA features and microarchitectural properties that are currently implemented with runtime patching. No one has stepped forward to take responsibility for that work, so many of us think it's best to remove it until clear use cases and champions emerge. Summary: - Add Kunit correctness testing and microbenchmarks for strlen(), strnlen(), and strrchr() - Add RISC-V-specific strnlen(), strchr(), strrchr() implementations - Add hardware error exception handling - Clean up and optimize our unaligned access probe code - Enable HAVE_IOREMAP_PROT to be able to use generic_access_phys() - Remove XIP kernel support - Warn when addresses outside the vmemmap range are passed to vmemmap_populate() - Update the ACPI FADT revision check to warn if it's not at least ACPI v6.6, which is when key RISC-V-specific tables were added to the specification - Increase COMMAND_LINE_SIZE to 2048 to match ARM64, x86, PowerPC, etc. - Make kaslr_offset() a static inline function, since there's no need for it to show up in the symbol table - Add KASLR offset and SATP to the VMCOREINFO ELF notes to improve kdump support - Add Makefile cleanup rule for vdso_cfi copied source files, and add a .gitignore for the build artifacts in that directory - Remove some redundant ifdefs that check Kconfig macros - Add missing SPDX license tag to the CFI selftest - Simplify UTS_MACHINE assignment in the RISC-V Makefile - Clarify some unclear comments and remove some superfluous comments - Fix various English typos across the RISC-V codebase" * tag 'riscv-for-linus-7.1-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (31 commits) riscv: Remove support for XIP kernel riscv: Reuse compare_unaligned_access() in check_vector_unaligned_access() riscv: Split out compare_unaligned_access() riscv: Reuse measure_cycles() in check_vector_unaligned_access() riscv: Split out measure_cycles() for reuse riscv: Clean up & optimize unaligned scalar access probe riscv: lib: add strrchr() implementation riscv: lib: add strchr() implementation riscv: lib: add strnlen() implementation lib/string_kunit: extend benchmarks to strnlen() and chr searches lib/string_kunit: add performance benchmark for strlen() lib/string_kunit: add correctness test for strrchr() lib/string_kunit: add correctness test for strnlen() lib/string_kunit: add correctness test for strlen() riscv: vdso_cfi: Add .gitignore for build artifacts riscv: vdso_cfi: Add clean rule for copied sources riscv: enable HAVE_IOREMAP_PROT riscv: mm: WARN_ON() for bad addresses in vmemmap_populate() riscv: acpi: update FADT revision check to 6.6 riscv: add hardware error trap handler support ...
2026-04-24Merge tag 'loongarch-7.1' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson Pull LoongArch updates from Huacai Chen: - Adjust build infrastructure for 32BIT/64BIT - Add HIGHMEM (PKMAP and FIX_KMAP) support - Show and handle CPU vulnerabilites correctly - Batch the icache maintenance for jump_label - Add more atomic instructions support for BPF JIT - Add more features (e.g. fsession) support for BPF trampoline - Some bug fixes and other small changes * tag 'loongarch-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson: (21 commits) selftests/bpf: Enable CAN_USE_LOAD_ACQ_STORE_REL for LoongArch LoongArch: BPF: Add fsession support for trampolines LoongArch: BPF: Introduce emit_store_stack_imm64() helper LoongArch: BPF: Support up to 12 function arguments for trampoline LoongArch: BPF: Support small struct arguments for trampoline LoongArch: BPF: Open code and remove invoke_bpf_mod_ret() LoongArch: BPF: Support load-acquire and store-release instructions LoongArch: BPF: Support 8 and 16 bit read-modify-write instructions LoongArch: BPF: Add the default case in emit_atomic() and rename it LoongArch: Define instruction formats for AM{SWAP/ADD}.{B/H} and DBAR LoongArch: Batch the icache maintenance for jump_label LoongArch: Add flush_icache_all()/local_flush_icache_all() LoongArch: Add spectre boundry for syscall dispatch table LoongArch: Show CPU vulnerabilites correctly LoongArch: Make arch_irq_work_has_interrupt() true only if IPI HW exist LoongArch: Use get_random_canary() for stack canary init LoongArch: Improve the logging of disabling KASLR LoongArch: Align FPU register state to 32 bytes LoongArch: Handle CONFIG_32BIT in syscall_get_arch() LoongArch: Add HIGHMEM (PKMAP and FIX_KMAP) support ...
2026-04-22LoongArch: Adjust build infrastructure for 32BIT/64BITHuacai Chen1-1/+1
Adjust build infrastructure (Kconfig, Makefile and ld scripts) to let us enable both 32BIT/64BIT kernel build. Reviewed-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-04-21Merge tag 'libcrypto-for-linus' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux Pull more crypto library updates from Eric Biggers: "Crypto library fix and documentation update: - Fix an integer underflow in the mpi library - Improve the crypto library documentation" * tag 'libcrypto-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux: lib/crypto: docs: Add rst documentation to Documentation/crypto/ docs: kdoc: Expand 'at_least' when creating parameter list lib/crypto: mpi: Fix integer underflow in mpi_read_raw_from_sgl()
2026-04-20rhashtable: Bounce deferred worker kick through irq_workTejun Heo1-3/+28
Inserts past 75% load call schedule_work(&ht->run_work) to kick an async resize. If a caller holds a raw spinlock (e.g. an insecure_elasticity user), schedule_work() under that lock records caller_lock -> pool->lock -> pi_lock -> rq->__lock A cycle forms if any of these locks is acquired in the reverse direction elsewhere. sched_ext, the only current insecure_elasticity user, hits this: it holds scx_sched_lock across rhashtable inserts of sub-schedulers, while scx_bypass() takes rq->__lock -> scx_sched_lock. Exercising the resize path produces: Chain exists of: &pool->lock --> &rq->__lock --> scx_sched_lock Bounce the kick from the insert paths through irq_work so schedule_work() runs from hard IRQ context with the caller's lock no longer held. rht_deferred_worker()'s self-rearm on error stays on schedule_work(&ht->run_work) - the worker runs in process context with no caller lock held, and keeping the self-requeue on @run_work lets cancel_work_sync() in rhashtable_free_and_destroy() drain it. v3: Keep rht_deferred_worker()'s self-rearm on schedule_work(&run_work). Routing it through irq_work in v2 broke cancel_work_sync()'s self-requeue handling - an irq_work queued after irq_work_sync() returned but while cancel_work_sync() was still waiting could fire post-teardown. v2: Bounce unconditionally instead of gating on insecure_elasticity, as suggested by Herbert. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
2026-04-20Merge tag 'printk-for-7.1' of ↵Linus Torvalds3-2/+26
git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux Pull printk updates from Petr Mladek: - Fix printk ring buffer initialization and sanity checks - Workaround printf kunit test compilation with gcc < 12.1 - Add IPv6 address printf format tests - Misc code and documentation cleanup * tag 'printk-for-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux: printf: Compile the kunit test with DISABLE_BRANCH_PROFILING DISABLE_BRANCH_PROFILING lib/vsprintf: use bool for local decode variable lib/hexdump: print_hex_dump_bytes() calls print_hex_dump_debug() printk: ringbuffer: fix errors in comments printk_ringbuffer: Add sanity check for 0-size data printk_ringbuffer: Fix get_data() size sanity check printf: add IPv6 address format tests printk: Fix _DESCS_COUNT type for 64-bit systems
2026-04-20Merge branch 'for-7.1-printf-kunit-build' into for-linusPetr Mladek83-730/+1131
2026-04-19Merge tag 'usb-7.1-rc1' of ↵Linus Torvalds1-0/+36
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb Pull USB / Thunderbolt updates from Greg KH: "Here is the big set of USB and Thunderbolt changes for 7.1-rc1. Lots of little things in here, nothing major, just constant improvements, updates, and new features. Highlights are: - new USB power supply driver support. These changes did touch outside of drivers/usb/ but got acks from the relevant mantainers for them. - dts file updates and conversions - string function conversions into "safer" ones - new device quirks - xhci driver updates - usb gadget driver minor fixes - typec driver additions and updates - small number of thunderbolt driver changes - dwc3 driver updates and additions of new hardware support - other minor driver updates All of these have been in the linux-next tree for a while with no reported issues" * tag 'usb-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (176 commits) usb: dwc3: starfive: Add JHB100 USB 2.0 DRD controller dt-bindings: usb: dwc3: add support for StarFive JHB100 dt-bindings: usb: atmel,at91sam9rl-udc: convert to DT schema dt-bindings: usb: atmel,at91rm9200-udc: convert to DT schema dt-bindings: usb: generic-ehci: fix schema structure and add at91sam9g45 constraints dt-bindings: usb: generic-ohci: add AT91RM9200 OHCI binding support arm: dts: at91: remove unused #address-cells/#size-cells from sam9x60 udc node drivers/usb/host: Fix spelling error 'seperate' -> 'separate' usbip: tools: add hint when no exported devices are found USB: serial: iuu_phoenix: fix iuutool author name usb: gadget: f_ncm: validate minimum block_len in ncm_unwrap_ntb() usb: gadget: f_phonet: fix skb frags[] overflow in pn_rx_complete() usb: gadget: f_hid: Add missing error code usb: typec: cros_ec_ucsi: Load driver from OF and ACPI definitions dt-bindings: chrome: Add cros-ec-ucsi compatibility to typec binding USB: of: Simplify with scoped for each OF child loop usbip: validate number_of_packets in usbip_pack_ret_submit() usb: gadget: renesas_usb3: validate endpoint index in standard request handlers usb: core: config: reverse the size check of the SSP isoc endpoint descriptor usb: typec: ucsi: Set usb mode on partner change ...
2026-04-19rhashtable: Restore insecure_elasticity toggleHerbert Xu1-2/+3
Some users of rhashtable cannot handle insertion failures, and are happy to accept the consequences of a hash table that having very long chains. Restore the insecure_elasticity toggle for these users. In addition to disabling the chain length checks, this also removes the emergency resize that would otherwise occur when the hash table occupancy hits 100% (an async resize is still scheduled at 75%). Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Tejun Heo <tj@kernel.org>
2026-04-19Merge tag 'mm-stable-2026-04-18-02-14' of ↵Linus Torvalds4-73/+189
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull more MM updates from Andrew Morton: - "Eliminate Dying Memory Cgroup" (Qi Zheng and Muchun Song) Address the longstanding "dying memcg problem". A situation wherein a no-longer-used memory control group will hang around for an extended period pointlessly consuming memory - "fix unexpected type conversions and potential overflows" (Qi Zheng) Fix a couple of potential 32-bit/64-bit issues which were identified during review of the "Eliminate Dying Memory Cgroup" series - "kho: history: track previous kernel version and kexec boot count" (Breno Leitao) Use Kexec Handover (KHO) to pass the previous kernel's version string and the number of kexec reboots since the last cold boot to the next kernel, and print it at boot time - "liveupdate: prevent double preservation" (Pasha Tatashin) Teach LUO to avoid managing the same file across different active sessions - "liveupdate: Fix module unloading and unregister API" (Pasha Tatashin) Address an issue with how LUO handles module reference counting and unregistration during module unloading - "zswap pool per-CPU acomp_ctx simplifications" (Kanchana Sridhar) Simplify and clean up the zswap crypto compression handling and improve the lifecycle management of zswap pool's per-CPU acomp_ctx resources - "mm/damon/core: fix damon_call()/damos_walk() vs kdmond exit race" (SeongJae Park) Address unlikely but possible leaks and deadlocks in damon_call() and damon_walk() - "mm/damon/core: validate damos_quota_goal->nid" (SeongJae Park) Fix a couple of root-only wild pointer dereferences - "Docs/admin-guide/mm/damon: warn commit_inputs vs other params race" (SeongJae Park) Update the DAMON documentation to warn operators about potential races which can occur if the commit_inputs parameter is altered at the wrong time - "Minor hmm_test fixes and cleanups" (Alistair Popple) Bugfixes and a cleanup for the HMM kernel selftests - "Modify memfd_luo code" (Chenghao Duan) Cleanups, simplifications and speedups to the memfd_lou code - "mm, kvm: allow uffd support in guest_memfd" (Mike Rapoport) Support for userfaultfd in guest_memfd - "selftests/mm: skip several tests when thp is not available" (Chunyu Hu) Fix several issues in the selftests code which were causing breakage when the tests were run on CONFIG_THP=n kernels - "mm/mprotect: micro-optimization work" (Pedro Falcato) A couple of nice speedups for mprotect() - "MAINTAINERS: update KHO and LIVE UPDATE entries" (Pratyush Yadav) Document upcoming changes in the maintenance of KHO, LUO, memfd_luo, kexec, crash, kdump and probably other kexec-based things - they are being moved out of mm.git and into a new git tree * tag 'mm-stable-2026-04-18-02-14' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (121 commits) MAINTAINERS: add page cache reviewer mm/vmscan: avoid false-positive -Wuninitialized warning MAINTAINERS: update Dave's kdump reviewer email address MAINTAINERS: drop include/linux/liveupdate from LIVE UPDATE MAINTAINERS: drop include/linux/kho/abi/ from KHO MAINTAINERS: update KHO and LIVE UPDATE maintainers MAINTAINERS: update kexec/kdump maintainers entries mm/migrate_device: remove dead migration entry check in migrate_vma_collect_huge_pmd() selftests: mm: skip charge_reserved_hugetlb without killall userfaultfd: allow registration of ranges below mmap_min_addr mm/vmstat: fix vmstat_shepherd double-scheduling vmstat_update mm/hugetlb: fix early boot crash on parameters without '=' separator zram: reject unrecognized type= values in recompress_store() docs: proc: document ProtectionKey in smaps mm/mprotect: special-case small folios when applying permissions mm/mprotect: move softleaf code out of the main function mm: remove '!root_reclaim' checking in should_abort_scan() mm/sparse: fix comment for section map alignment mm/page_io: use sio->len for PSWPIN accounting in sio_read_complete() selftests/mm: transhuge_stress: skip the test when thp not available ...
2026-04-18Merge tag 'memblock-v7.1-rc1' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/rppt/memblock Pull memblock updates from Mike Rapoport: - improve debuggability of reserve_mem kernel parameter handling with print outs in case of a failure and debugfs info showing what was actually reserved - Make memblock_free_late() and free_reserved_area() use the same core logic for freeing the memory to buddy and ensure it takes care of updating memblock arrays when ARCH_KEEP_MEMBLOCK is enabled.