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2026-09-01ftrace: Take trace_array reference before accessing its ftrace_opsSteven Rostedt4-24/+42
The trace instance files set_ftrace_filter and set_ftrace_notrace was updated to work with specific trace instances (trace_arrays). The issue is that when these files are opened, there is a small race window where it will use the ftrace_ops from the inode->private pointer to get a reference to the trace_array and then take its reference. The problem is that the ftrace_ops itself could be freed. If the rmdir on the instance happens at the same time the set_ftrace_filter file is opened, the rmdir could have also freed the ftrace_ops and referencing it will cause a use-after-free bug and crash the kernel. Instead, pass in the trace_array as the file private data (NULL for the top level instance), and then pass both the trace_array and the ftrace_ops to the ftrace_regex_open() function. If the trace_array is NULL, then it just uses the ftrace_ops without the need to take its reference (like normal). If the ftrace_ops is NULL, that is only the case for the top level instance and the global_ops can be used. This allows the trace_array to have its reference incremented before touching the ftrace_ops that could also be freed when the instance is. Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260828223901.29e26edb@robin Fixes: 591dffdade9f0 ("ftrace: Allow for function tracing instance to filter functions") Reported-by: Breno Leitao <leitao@debian.org> Tested-by: Breno Leitao <leitao@debian.org> Closes: https://lore.kernel.org/all/apGORjltZgAiAYHT@gmail.com/ Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-09-01tracing: Have show_event_filters/triggers files take trace array refSteven Rostedt1-4/+24
The newly added files show_event_filters and show_event_triggers that show all filters or triggers that are set within the trace array do not take a reference for the trace array it is showing. Without taking a reference, the trace_array may be freed via "rmdir" while a task is reading one of theses files. Those files iterate all the events within an instance (trace_array) and nothing prevents that instance from being freed while its data is being read. This causes a use-after-free crash. Have the open of both those files take the trace_array reference via the trace_array_get() that prevents the trace_array from being freed while the files are opened. Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260828094153.17b95037@gandalf.local.home Fixes: 729757b96a662 ("tracing: Add show_event_filters to expose active event filters") Fixes: 6a80838814eea ("tracing: Add show_event_triggers to expose active event triggers") Reported-by: Farhad Alemi <farhad.alemi@berkeley.edu> Closes: https://lore.kernel.org/all/CA+0ovCjerKZJLwXScM9bF2ga2rLi4_XOpUfK41NDbENpeu98jA@mail.gmail.com/ Reviewed-by: Aaron Tomlin <atomlin@atomlin.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-09-01uprobes: guard trace cleanup against error pointersAndi Kleen1-2/+2
Sashiko pointed out the some of the scope cleanups for free_uprobe could get an error pointer. Handle this case in free_uprobe to prevent a crash. On the other hand the macro doesn't need the guard because free_uprobe itself already does the check. Link: https://lore.kernel.org/all/20260831150651.1134594-2-ak@kernel.org/ Assisted-by: omp:gpt-5.6-luna sashiko Signed-off-by: Andi Kleen <ak@kernel.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-08-31sched_ext: Pass the initial cpu.idle state in scx_cgroup_init_argsTao Cui3-1/+8
scx_cgroup_init_args carries the initial weight and bandwidth control parameters of a cgroup to ops.cgroup_init(), but not its cpu.idle state. A cgroup that was already configured idle before the scheduler was loaded (or before it was onlined under it) is presented as non-idle, and the BPF scheduler only learns about it if cpu.idle is written again later. Add the sched_idle state to scx_cgroup_init_args and fill it in all four places that build the args: scx_tg_online() for cgroups onlined under the scheduler, scx_cgroup_init() for cgroups that already exist when the scheduler is loaded, and the sub-scheduler handover paths scx_cgroup_claim_subtree() and scx_cgroup_return_subtree(). Verified in a VM with a probe scheduler printing the init args: a cgroup configured cpu.idle=1 before loading shows sched_idle=1 in ops.cgroup_init(), the default shows 0, and later cpu.idle writes still come through ops.cgroup_set_idle(). The sub-scheduler paths are compile-tested only. Fixes: 347ed2d566da ("sched/ext: Implement cgroup_set_idle() callback") Signed-off-by: Tao Cui <cuitao@kylinos.cn> Reviewed-by: Andrea Righi <arighi@nvidia.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2026-08-31Merge tag 'wq-for-7.3-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wqLinus Torvalds1-9/+21
Pull workqueue fixes from Tejun Heo: - An unbound worker pool could be freed while still reachable through the pending-activation list, leading to a use-after-free. Unlink before dropping the reference - On PREEMPT_RT, the BH workqueue kick raised softirqs from preemptible context, tripping a lockdep assertion and possibly losing concurrently raised softirq bits - Draining BH work off a dead CPU nests two pools' callback locks, which lockdep misreported as recursive locking. The nesting cannot deadlock. Annotate it - Reject watchdog thresholds that overflow the conversion to jiffies - Make the drgn workqueue dump script work again on kernels and vmcores from before the workqueue attrs field rename * tag 'wq-for-7.3-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: tools/workqueue/wq_dump.py: Support backward compatibility for wq->attrs rename workqueue: reject watchdog thresholds that overflow jiffies workqueue: Fix unbound pool lifetime for pending pwqs workqueue: Use raise_softirq() to trigger softirq in irq_work handler workqueue: Annotate cb_lock nesting when draining a dead BH pool
2026-08-31Merge tag 'cgroup-for-7.3-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroupLinus Torvalds2-14/+31
Pull cgroup fixes from Tejun Heo: - After cgroup.kill was written to a cgroup, every child cloned into it with CLONE_INTO_CGROUP was spuriously killed because the fork path snapshotted the kill counter before resolving the target cgroup - Releasing an isolated cpuset partition dropped the isolation of CPUs isolated on the kernel command line - Selftest and documentation fixes * tag 'cgroup-for-7.3-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: selftests/cgroup: test clone3() into a previously killed cgroup cgroup: fix spurious SIGKILL of CLONE_INTO_CGROUP children selftests/cgroup: Add test for preserving boot-isolated CPUs cgroup/cpuset: Preserve boot-isolated CPUs on partition release selftests/cgroup: Drop invalid boot isolation comparison docs: cgroup-v2: fix misc.events key format description selftests/cgroup: Fix cg_run_in_subcgroups ignoring arg parameter selftests/cgroup: set the test plan after the setup checks
2026-08-31Merge tag 'sched_ext-for-7.3-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_extLinus Torvalds2-15/+57
Pull sched_ext fixes from Tejun Heo: - The task ownership check in the dispatch queue move operation raced against the task exiting or moving to a different sub-scheduler, spuriously triggering scheduler aborts. Fix by moving the check under the queue lock - The cgroup bandwidth change callback runs in a sleepable context but sleepable implementations were rejected at load time. Allow them and add a marker so userspace can detect the capability - Sync tooling headers with the scx repo for accumulated compatibility improvements - Example scheduler fixes: ignored timer re-arm failures and vtime credit loss on cgroup migration - Documentation and comment fixes * tag 'sched_ext-for-7.3-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext: sched_ext: Fix missing @slice and @vtime descriptions in finish_dispatch() kernel-doc sched_ext: Fix several comment issues sched_ext: Check bpf_timer_start return values in scx_qmap sched_ext: Fix vtime delta loss in scx_flatcg cgroup migration sched_ext: Fix timer pinning and return value in scx_central docs/sched_ext: document that cgroup CPU knobs are scheduler-dependent sched_ext: Fix spurious aborts in scx_bpf_dsq_move() on ownership change races sched_ext: Sync common and compat headers from the scx repo sched_ext: Sync tools autogen enum headers from the scx repo Docs/admin-guide/cgroup-v2: document BPF scheduler callbacks for cpu.max and cpu.idle sched_ext: Fix nonexistent field in sched-ext.rst example sched_ext: Allow ops.cgroup_set_bandwidth() to be sleepable
2026-08-31Merge tag 'xfs-fixes-7.3-rc2' of gitolite.kernel.org:/pub/scm/fs/xfs/xfs-linuxLinus Torvalds1-1/+18
Pull xfs fixes from Carlos Maiolino: "This contains a few fixes for the zoned storage support, a possible deadlock vector fix, some code refactoring patches and a quota evasion fix on XFS while exporting it via NFS. Please note that for the quota evasion fix, a couple patches for the capability subsystem are included in the pull request. Those have been ack'ed by the respective maintainer which also agreed to have them going through the xfs tree. This also includes a patch for the quota subsystem to stop issuing audit messages during quota enforcing. Quota maintainer also ack'ed and agreed with this going through xfs tree" * tag 'xfs-fixes-7.3-rc2' of gitolite.kernel.org:/pub/scm/fs/xfs/xfs-linux: capability: unexport has_capability_noaudit xfs: replace ns_capable_noaudit quota: Don't issue audit messages on quota enforcing capability: Add new capable_noaudit xfs: fix capability check in xfs xfs: restore bi_bdev in xfs_zone_gc_write_chunk xfs: split ioend handling into a separate source file xfs: factor out a xfs_iomap_set_anon_write helper xfs: fix zoned write iomap flags assignments xfs: fix racy open zone caching xfs: handle NULL open_zone for merged ioends in xfs_ioend_put_open_zones xfs: use inode_init_always_gfp with __GFP_NOFAIL in xfs_inode_alloc xfs: remove kmem_to_page() xfs: don't flush and invalidate internal RT device twice in xfs_shutdown_devices xfs: split an assert in xfs_trans_log_buf xfs: don't hold buffer locks across sync transaction commit in xfs_sync_sb_buf
2026-08-31workqueue: reject watchdog thresholds that overflow jiffiesJiacheng Xu1-0/+3
The watchdog threshold is supplied in seconds but is multiplied by HZ before being used as a jiffies interval. Reject values that exceed MAX_JIFFY_OFFSET / HZ so the multiplication cannot wrap and the time_after() comparisons remain within their supported range. The check is performed before changing the threshold or watchdog timer. Zero remains the value used to disable the watchdog. Fixes: 82607adcf9cdf ("workqueue: implement lockup detector") Signed-off-by: Jiacheng Xu <stitch@zju.edu.cn> Signed-off-by: Tejun Heo <tj@kernel.org>
2026-08-31sched_ext: Fix missing @slice and @vtime descriptions in finish_dispatch() kernel-docLiang Luo1-0/+2
Commit 13f1eae3b662 ("sched_ext: Synchronize slice and dsq_vtime writes") added the slice and vtime parameters to finish_dispatch() but did not update its kernel-doc, which produces warnings: Warning: function parameter 'slice' not described in 'finish_dispatch' Warning: function parameter 'vtime' not described in 'finish_dispatch' Describe both parameters using the same wording as dispatch_to_local_dsq(), which receives the same values. Signed-off-by: Liang Luo <luoliang@kylinos.cn> Signed-off-by: Tejun Heo <tj@kernel.org>
2026-08-31sched_ext: Fix several comment issuesWanwu Li2-6/+6
Fix several comment issues found during review: __setschduler_prio() -> __setscheduler_class() scx_iter_scx_dsq_new() -> bpf_iter_scx_dsq_new() scx_next_task_scx() -> set_next_task_scx() Signed-off-by: Wanwu Li <liwanwu@kylinos.cn> Signed-off-by: Tejun Heo <tj@kernel.org>
2026-08-31cgroup: fix spurious SIGKILL of CLONE_INTO_CGROUP childrenEtienne Perot1-4/+2
Since commit b69bb476dee9 ("cgroup: fix race between fork and cgroup.kill"), the fork path snapshots the kill_seq of the child's future cgroup into kargs->kill_seq, and cgroup_post_fork() SIGKILLs the child if that cgroup's kill_seq has changed in the meantime, to catch forks racing with a cgroup.kill sweep. For CLONE_INTO_CGROUP, however, the snapshot in cgroup_css_set_fork() is taken before the target cgroup has been resolved: kargs->cgrp is always NULL at this point (it is only set at the end of the function). So the "if (kargs->cgrp)" branch is dead code and the snapshot always records the kill_seq of the parent's cgroup. cgroup_post_fork() then compares it with the kill_seq of the target cgroup, so the child gets SIGKILLed whenever the two cgroups have been killed a different number of times. As a result, once cgroup.kill has been written to a cgroup, every child subsequently cloned into it with clone3(CLONE_INTO_CGROUP) is killed on the spot, for as long as the cgroup exists: kill_seq is not exposed to userspace and never resets. Re-snapshot kill_seq from the target cgroup once it has been resolved, and drop the dead branch at the early snapshot site. This does not reopen the race fixed by b69bb476dee9. For CLONE_INTO_CGROUP, everything from the snapshot to the check in cgroup_post_fork() runs with cgroup_mutex held, and kill_seq is only ever incremented under cgroup_mutex. tj: Updated the comment above kill_seq to reflect the new serialization rules as suggested by Shakeel Butt. Fixes: b69bb476dee9 ("cgroup: fix race between fork and cgroup.kill") Cc: stable@vger.kernel.org Cc: Shakeel Butt <shakeel.butt@linux.dev> Assisted-by: LLM Signed-off-by: Etienne Perot <eperot@google.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2026-08-31reboot: fix cad_pid use-after-free raceCen Zhang (Microsoft)2-4/+27
cad_pid is a single kernel-wide struct pid pointer. proc_do_cad_pid() reads it and passes it to pid_vnr() without protecting the lifetime of the referenced struct pid. A concurrent writer can replace cad_pid and drop the final reference to the old struct pid after the reader has loaded the pointer but before pid_vnr() has finished dereferencing it, causing a use-after-free. kill_cad_pid() has the same lifetime race when it passes cad_pid to kill_pid(). At the time this issue was reported, an unprivileged user could reach the sysctl through user and PID namespaces because cad_pid was registered in pid_table[]. Moving cad_pid back to the global reboot sysctl table corrected that namespace and permission mismatch, but did not fix the underlying lifetime race. Fix this by treating cad_pid as an RCU-protected pointer at both read sites and by waiting for a grace period before dropping the old reference on the write side. call_rcu(&old_pid->rcu, ...) cannot be used here because free_pid() also queues pid->rcu; queueing the same rcu_head twice can corrupt the RCU callback list. Original KASAN crash stack: kernel/pid.c:545 pid_nr_ns() # reads freed pid->level kernel/pid.c:556 pid_vnr() # calls pid_nr_ns() kernel/pid.c:775 proc_do_cad_pid() # calls pid_vnr(cad_pid) Fixes: 9ec52099e4b8 ("[PATCH] replace cad_pid by a struct pid") Reported-by: AutonomousCodeSecurity@microsoft.com Closes: https://lore.kernel.org/all/20260717210143.4734-1-blbllhy@gmail.com/ Link: https://lore.kernel.org/all/alz5ZYLE4kaq_v2P@redhat.com/ Link: https://lore.kernel.org/all/al4ICz9biJKtdZc4@redhat.com/ Suggested-by: Mateusz Guzik <mjguzik@gmail.com> Suggested-by: Bradley Morgan <include@grrlz.net> Suggested-by: Oleg Nesterov <oleg@redhat.com> Suggested-by: Eric W. Biederman <ebiederm@xmission.com> Suggested-by: Pavel Tikhomirov <ptikhomirov@virtuozzo.com> Cc: stable@vger.kernel.org Signed-off-by: Cen Zhang (Microsoft) <blbllhy@gmail.com> Link: https://patch.msgid.link/20260814040944.16561-1-blbllhy@gmail.com Reviewed-by: Bradley Morgan <include@grrlz.net> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Reviewed-by: Pavel Tikhomirov <ptikhomirov@virtuozzo.com> Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-08-30Merge tag 'locking-urgent-2026-08-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-6/+6
Pull locking fix from Ingo Molnar: - Revert a commit to spinlock cleanup guards that got caught up in the subtle limitations & fragility of guards (again...) and caused a regression (Peter Zijlstra) * tag 'locking-urgent-2026-08-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: locking: Revert switching guards to _irq_{disable,enable}()
2026-08-30Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-traceLinus Torvalds6-6/+20
Pull tracing fixes from Steven Rostedt: - Fix error output of boot instance creation failure Currently if a boot instance creation fails, instead of printing out the name of the instance that failed, it prints "(null)". That is because it prints "cur_str" that had already been processed by strsep(). Print the saved name instead. While at it, print the error code of the failure. - Fix use-after-free for same named historgrams Histograms can be named so that they can be used in multiple events. But if the named histogram has a variable attached, the second event that uses the named histogram which duplicates it and needs to free the original after duplication leaves the old variable in place and still visible. If another histogram uses than variable, it will use the stale one which will try to reference the freed duplicate histogram and crash the kernel. Free the duplicate variables along with the duplicated histogram data. - Check return value of kthread_run() in event self test The events self tests uses a kthread for testing but does not check if it succeeded in creating a kthread. If the kthread creation were to fail, the code will still try to call kthread_stop() on the error returned. - Fix race between reading trace_pipe and updating subbuffer size If a user is reading the trace_pipe file at the same time they update the ring buffer sub-buffer size, can cause the trace_pipe read to read stale data. Add trace_access_lock() around updating the ring buffer sub-buffer size. - Fix eventfs_inode on failure path in creation of the events directory In the creation of the "events" directory, if after allocating the eventfs_inode a failure is detected, it calls cleanup_ei() which calls free_ei(). The free_ei() will test if eventfs_inode being freed has no children. It is a bug if it does. But on the failure case of the creation of the "events" directory, the children lists have not yet been initialized and the free will trigger a warning because list_empty() on an uninitialized list returns false. Move the initialization into init_ei() where it makes more sense and makes sure that a created eventfs_inode has its lists initialized upon creation. - Check return value of kthread_run() in ftrace direct sample code The sample code that shows how to use the ftrace direct calls does not test the return of kthread_run() to see if it succeeds. Return a failure if the kthread_run() doesn't succeed. - Clear user events state on fork in case of alloc failure On fork, the child gets a pointer to the parent's user events state. It makes a copy of it then updates the child's pointer to it. But if the allocation fails, the duplication function leaves the child with a pointer to its parent's descriptor. When the child cleans up its data, it will free the parent's descriptor while the parent is still using it. In the duplication function, set the child's user_event_mm to NULL before testing if the allocation succeeded, and when it exits it will not free the parent's descriptor. - Fix retry exhaustion in simple ring buffer reader swap simple_ring_buffer_swap_reader_page() starts with retry set to 8 and post-decrements it only after a failed link replacement. On the final attempt, a successful replacement leaves retry at zero, while a failed replacement leaves it at -1. But the check for success expects the retry value to be non-zero and exits with an error on zero. This is the opposite result. Fix it. - Fail nicely when the remote swap_reader_page() returns an error Currently, if the swap_reader_page() of a remote buffer fails, it triggers a WARN_ON_ONCE() and continues normally. Instead, have it exit with an error and a pr_warn() print instead of a full WARNING. * tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: ring-buffer: Stop remote reader update when page swap fails tracing: Fix retry exhaustion in simple ring buffer reader swap tracing/user_events: Clear copied tracing state before fork duplication samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify eventfs: Initialize ei->children and ei->list in init_ei() tracing: Fix use-after-free in trace_pipe read on sub-buffer order change tracing: Fix crash passing ERR_PTR to kthread_stop() tracing: Fix use-after-free with same-name named triggers tracing: Fix logged instance name on creation failure
2026-08-30interrupt: Disable interrupt before modifying hardirq_disable counterBoqun Feng1-13/+4
Currently a softirq may be pending longer then expected if the triggering interrupt happens in-between hardirq_disable_enter() and _local_interrupt_disable() in local_interrupt_disable(): local_interrupt_disable(): hardirq_disable_enter(); <interrupt> ... __irq_exit_rcu(): // false because hardirq_disable_count() is not 0 if (.. && !hardirq_disable_count() && ..) { invoke_softirq(); } _local_interrupt_disable(); , it'll defer the softirq to the next interrupt which can be forever. The order between hardirq_disable_enter() and _local_interrupt_disable() is to optimize re-disabling interrupts if they are already disabled, but as 1) local_interrupt_disable() is not widely used yet and 2) the proper way to achieve this optimization may need fixing up the counter at entry/exit time [1], so reverse the order for now to avoid the softirq pending issue. Because of this fix, the part of saving the current state is separated from irq disabling, and the logic of local_interrupt_disable() becomes: local_irq_save(flags); if (counter++ == 0) { this_cpu(local_interrupt_disable_state) = flags; } Therefore change the helper function _local_interrupt_disable() to _local_interrupt_save_state() which only saves the current irqflags (when interrupts get disabled the first time). Fixes: e901c1510e24 ("irq,spin_lock: Add counted interrupt disabling/enabling") Reported-by: Thomas Gleixner <tglx@kernel.org> Signed-off-by: Boqun Feng <boqun@kernel.org> Signed-off-by: Thomas Gleixner <tglx@kernel.org> Reviewed-by: Bradley Morgan <brads@mainlining.org> Link: https://patch.msgid.link/20260829213412.14303-1-boqun@kernel.org Link: https://lore.kernel.org/lkml/87v78wezid.ffs@fw13/ [1] Closes: https://lore.kernel.org/lkml/87jypbfu1t.ffs@fw13/
2026-08-28bpf: don't downgrade half-dead scalar zero spills to STACK_ZEROEduard Zingerman1-7/+4
states.c:__clean_func_state() can downgrade scalar zero spill to STACK_ZERO in the following case: *(u64 *)(r10 - 8) = 0; ... checkpoint ... r1 = *(u32 *)(r10 - 4); ... no reads from r10-8 ... Here 4 bytes at r10-8 are dead and verifier changes scalar spill to a combination: 0000pppp (p stands for poison). Such a change breaks precision propagation chains. All places that produce STACK_ZERO should call bpf_mark_chain_precision() for the zero source. This patch fixes the bug in a simplest way possible: avoids converting stack spills of zero to STACK_ZERO. Two smarter approaches are possible: - do bpf_mark_chain_precision() from __clean_func_state() - check slot liveness information in check_stack_write_fixed_off() I investigated both and the changes required are a bit tricky, hence go with a simple fix for the time being. Fixes: be23266b4a08 ("bpf: 4-byte precise clean_verifier_state") Reported-by: Nicholas Carlini <npc@anthropic.com> Suggested-by: Nicholas Carlini <npc@anthropic.com> Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20260827-bug-011-cleanfunc-stack-zero-simple-v1-v1-1-c0e996589a52@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-08-27ring-buffer: Stop remote reader update when page swap failsIvan Immanuel Shaji1-2/+5
The remote swap_reader_page callback can return -EBUSY when the writer moves the head before the remote catches it, particularly during an event storm on a small buffer. __rb_get_reader_page_from_remote() currently warns about that failure but continues with the unchanged reader ID and rearranges the local page list as though the swap succeeded. Handle the callback failure as a recoverable error. Report it with pr_warn_ratelimited() and return NULL. Callers already handle a NULL reader page as a failed attempt. This avoids splicing the same page as both the previous and new reader without flooding the log under contention. Cc: stable@vger.kernel.org Fixes: 2e67fabd8b77 ("ring-buffer: Introduce ring-buffer remotes") Link: https://patch.msgid.link/20260825-kernel-patch-1-v2-2-bb3461807a32@gmail.com Assisted-by: LLM sparse Signed-off-by: Ivan Immanuel Shaji <ivanimmanuel1234@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-08-27tracing: Fix retry exhaustion in simple ring buffer reader swapIvan Immanuel Shaji1-2/+2
simple_ring_buffer_swap_reader_page() starts with retry set to 8 and post-decrements it only after a failed link replacement. On the final attempt, a successful replacement leaves retry at zero, while a failed replacement leaves it at -1. The current !retry test reverses both outcomes. It returns an error after a successful final replacement, leaving the link update complete but the reader bookkeeping unfinished. After a failed final replacement, it falls through and updates the head and reader pointers as though the replacement succeeded, which can corrupt the ring. Treat only a negative counter as exhaustion and return the documented -EBUSY error. Cc: stable@vger.kernel.org Fixes: 34e5b958bdad ("tracing: Introduce simple_ring_buffer") Link: https://patch.msgid.link/20260825-kernel-patch-1-v2-1-bb3461807a32@gmail.com Assisted-by: LLM sparse Reviewed-by: Vincent Donnefort <vdonnefort@google.com> Signed-off-by: Ivan Immanuel Shaji <ivanimmanuel1234@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-08-27tracing/user_events: Clear copied tracing state before fork duplicationJérémy Jean1-0/+3
dup_task_struct() copies user_event_mm from the parent into the child, without grabbing a reference to it. user_event_mm_dup() should replace it, but it leaves that copied pointer unmodified if user_event_mm_alloc() fails. When the child exits, user_event_mm_remove() decrements a reference the child never owned, which ultimately frees user_event_mm, while the parent still as a stale pointer to it. This creates a UAF, which KASAN reports as: BUG: KASAN: slab-use-after-free in current_user_event_mm+0x51/0x1d0 Write of size 4 at addr ffff888005010d30 by task init/44 Call Trace: <TASK> kasan_report+0xce/0x100 kasan_check_range+0x10f/0x1e0 current_user_event_mm+0x51/0x1d0 user_events_ioctl+0x82e/0x15c0 __x64_sys_ioctl+0x139/0x1c0 do_syscall_64+0xce/0x450 entry_SYSCALL_64_after_hwframe+0x77/0x7f Allocated by task 44: __kasan_kmalloc+0x8f/0xa0 __kmalloc_cache_noprof+0x180/0x3a0 user_event_mm_alloc+0x3c/0x1f0 current_user_event_mm+0x88/0x1d0 Freed by task 42: __kasan_slab_free+0x43/0x70 kfree+0x13a/0x390 process_one_work+0x696/0xf90 worker_thread+0x420/0xba0 The fix simply clears the copied pointer before any possible failure. In case of failure, the child then has nothing to free. Cc: stable@vger.kernel.org Fixes: 7235759084a4 ("tracing/user_events: Use remote writes for event enablement") Link: https://patch.msgid.link/20260827184321.2964601-2-Jeremy.Jean@oss.cyber.gouv.fr Assisted-by: Codex:gpt-5 Signed-off-by: Jérémy Jean <Jeremy.Jean@oss.cyber.gouv.fr> Reviewed-by: Bradley Morgan <brads@mainlining.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-08-27Merge tag 'dma-mapping-7.3-2026-08-27' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linuxLinus Torvalds1-7/+9
Pull dma-mapping fix from Marek Szyprowski: - integer overflow fix for kernel cmdline parser for DMA contiguous initialization code (Alexander Graf) * tag 'dma-mapping-7.3-2026-08-27' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux: dma-contiguous: fix truncation of numa_cma / cma_pernuma sizes >= 2G
2026-08-27Merge tag 'mm-stable-2026-08-26-15-22' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mmLinus Torvalds2-8/+52
Pull more MM updates from Andrew Morton: - "mm/rmap: index MAP_PRIVATE file-backed folios by anonymous pgoff" (Lorenzo Stoakes) Index MAP_PRIVATE file-backed folios by their anonymous page offset to resolve confusion around reverse mapping for zeroed and CoW'd file-backed memory. Use this new VMA anonymous page offset tracking to eliminate index conflicts and lay the foundation for scalable CoW performance improvements. - "promote mapped executable folios after first usage for MGLRU" (Baolin Wang) Make MGLRU's protection of mapped executable file folios more reliable. Follow the classical LRU's logic, promoting mapped executable file folios after their first usage to give executable code a better chance to stay in memory and improve workload performance. - "mm: vmscan: fix node reclaim ignoring swappiness parameter" (Ridong Chen) Fix per-node proactive reclaim interface's ignoring the swappiness parameter when CONFIG_MEMCG is disabled by consolidating sc_swappiness() into a single function that checks proactive_swappiness regardless of kernel configuration. - "mm/vmscan: reduce lru_lock contention via vmstat-derived scan-balance cost" (Usama Arif) Reduce lru_lock contention in the reclaim path by deriving scan-balance costs from vmstat counters rather than lock-acquired producer updates. Read and decay these cost signals on the reclaim side under a dedicated per-lruvec lock, reducing total LRU lock wait time by over 60% without impacting scan throughput. - "zram: fix zram issues reported by sashiko" (Sergey Senozhatsky) Fix two low-risk zram bugs which Sashiko spotted in drive-by review. - "Honor XA_FLAGS_ACCOUNT in xas_split_alloc() and charge to folio's memcg" (Zi Yan) Fix xas_split_alloc() by enabling target folio memcg charging during splits and adding the missing __GFP_ACCOUNT flag for proper XArray node memory accounting. - "selftests/mm: use pattern matching in .gitignore" (Pratyush Mallick) Replace hardcoded binary names in selftests/mm/.gitignore with a generic pattern-matching rule to automatically ignore generated test files and avoid manual updates when adding new tests. - "mm/page_ext: remove pgdat_page_ext_init()" (Sang-Heon Jeon) Make the incompatibility between FLATMEM and NUMA explicit in mm/Kconfig and remove the unused pgdat_page_ext_init() function. - "zram: fix zstd error paths and add parameter validation" (Haoqin Huang) Clean up zram compression backends by removing redundant error cleanup, adding parameter and dictionary validation, auto-prefixing algorithm error logs, and resetting parameters prior to reinitialization. - "zram: fix stale scan bounds after reinitialization" (Longlong Xia) Prevent out-of-bounds slot accesses during concurrent zram resets by moving table scan bound calculations under dev_lock in writeback_store() and read_block_state(). - "add anon mTHP collapse test cases" (Baolin Wang) Extend selftests helper functions to support arbitrary page orders and add new test cases and options for mTHP collapse in khugepaged. - "selftests/mm: Handle unsupported and transient test conditions" (Muhammad Usama Anjum) Update MM selftests to report a SKIP status instead of a failure when required kernel or filesystem features are unsupported, while adding retry logic for transient page migration errors. - "mm/zswap: Fixes and improves the zswap shrink" (Hao Jia) Fix the missing zswap global shrinker when CONFIG_MEMCG is disabled and extend shrink_memcg() to support batch writeback for improved writeback efficiency. - "alloc_tag: introduce IOCTL-based filtering for MAP" (Suren Baghdasaryan) Introduce an IOCTL-based binary interface for memory allocation profiling that enables kernel-side filtering before per-CPU counter aggregation. This eliminates the text-parsing overhead of /proc/allocinfo and provides up to a 20x speedup by transferring only filtered allocation data to userspace. - "better block swap batching and a different take on swap_ops v5" (Christoph Hellwig) Refactor block swap I/O to use swap_iocb for batching instead of single-bio requests and rebase the swap_ops interface, achieving faster swap throughput during kernel builds. - "mm: kmemleak: reduce transient false positives by confirming leaks" (Catalin Marinas) Reduce false-positive kmemleak reports by combining two kmemleak enhancements that add a second confirmation scan and a configurable minimum unreferenced scan count module parameter. - "mm: kmemleak: default min_unref_scans to 2 for verbose kernels" (Breno Leitao) Auto-scanning kernels can generate false-positive memory leak reports on single scans, so this patch defaults min_unref_scans to 2 when CONFIG_DEBUG_KMEMLEAK_VERBOSE is enabled to require a second confirming scan. - "swap_ops updates" (Christoph Hellwig) Batching I/O for synchronous swap devices causes performance regressions and filesystem-based swap suffers from double-indirection overhead. This series resolves both issues by reintroducing per-folio writes for synchronous swap and allowing filesystems to directly export their own swap_ops. - "mm/khugepaged: several cleanups" (Nico Pache) khugepaged accumulated redundant state-checking patterns and outdated comments following mTHP integration. Introduce dedicated helpers for PTE validation and event counting while refreshing the internal documentation. - "maple_tree: lock checking and clean ups" (Liam Howlett) Syzbot reports incorrectly blame memory management exit paths for locking bugs, maple tree erase operations risk allocation failures without gfp flags and internal documentation lacks clarity. Improve lock error detection, update docs, fix race and allocation edge cases and optimize erase allocations using a fallback to GFP_KERNEL | GFP_NOFAIL. * tag 'mm-stable-2026-08-26-15-22' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (172 commits) selftests/proc: make proc-maps-race work with READ_IMPLIES_EXEC memcg: move LRU size accounting on reparenting instead of copying it mm/vmscan: fix comment logic in balance_pgdat maple_tree: add helper mas_make_walkable() maple_tree: avoid extra gap calculation maple_tree: fix argument name in header maple_tree: change two GFP flags in tests maple_tree: document erase and allocations better maple_tree: avoid mas_erase() and mtree_erase() failures maple_tree: document that erase may use GFP_KERNEL for allocations maple_tree: catch race in mas_alloc_cyclic() maple_tree: add bulk parent set helper maple_tree: micro optimisation of mas_wr_store_type() maple_tree: optimise mas_wr_node_store() when not in rcu mode maple_tree: use prefetched value in mas_wr_store_type() maple_tree: clarify comments on mas_nomem() maple_tree: drop MAPLE_ALLOC_SLOTS maple_tree: drop dead code from mas_extend_spanning_null() maple_tree: documentation fix maple_tree: add write lock checking with lockdep sequence numbers ...
2026-08-26bpf: check_cond_jmp_op(): properly infer if register is nullEduard Zingerman1-3/+6
Nicholas Carlini reported a bug when verifier can incorrectly infer that a pointer is non-null. The bug occurs when two pointers are compared and one of them has a type w/o PTR_MAYBE_NULL flag, but which allows a value to be NULL at runtime. Here is an example: // `a` is PTR_TO_MEM | MEM_RDONLY | PTR_UNTRUSTED // `a` is 0 at runtime. // `b` is PTR_TO_MAP_VALUE | PTR_MAYBE_NULL void *a = bpf_rdonly_cast(0, 0); int *b = bpf_map_lookup_elem(...); if (a == b) *b = 42; // verifier does not catch null pointer dereference This happens because of a special case in check_cond_jmp_op(), which attempts to strip PTR_MAYBE_NULL flags from pointer types, when processing comparisons like `rA == rB`, if either rA or rB can't be null. The non-null property is derived based on the absence of PTR_MAYBE_NULL flag on rA's or rB's type. But that is not sufficient for types like PTR_TO_MEM, as in the example. This patch replaces type_may_be_null() call with reg_not_null(), which contains an allowlist of types for which absence of PTR_MAYBE_NULL actually means that the value can't be NULL at runtime. At the moment, the list in the reg_not_null() omits two types for which PTR_MAYBE_NULL is applicable: PTR_TO_XDP_SOCK and PTR_TO_BUF. In order to remain backward compatible, and assuming that only comparison between pointers of the same type makes sense, this commit extends reg_not_null(). W/o such an extension e.g. verifier_jeq_infer_not_null/null_ptr_to_map_value fails. reg_not_null() can be extended further, but I deem that out of scope for the fix at hand. Explicit base_type(...) != PTR_TO_BTF_ID checks in the check_cond_jmp_op() can be removed with migration to reg_not_null(), but that is a behavioural change, as the special case would start matching for PTR_TO_BTF_ID that is also is_trusted_reg(). I omit the behavioural change from this commit. Fixes: befae75856ab ("bpf: propagate nullness information for reg to reg comparisons") Suggested-by: Nicholas Carlini <npc@anthropic.com> Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20260826-bug-029-bad-non-null-inference-v2-1-136789ace9e9@localhost Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-08-26Merge tag 'nfs-for-7.3-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfsLinus Torvalds1-0/+24
Pull NFS client updates from Trond Myklebust: "Highlights include: Stable fixes: - Use-after-free fixes for the sunrpc client code - Delegation hash table leak - NULL dereference on lockowner allocation failure - Fix a handshake completion race in the TLS code - Fix an error sign checking issue when deciding whether the pNFS layout is still in use, or can be returned - Fix a layout segment leak in pnfs_layout_process() Other bugfixes: - Fix a missing NULL check in the rpcbind client - annotate shared socket callbacks with READ_ONCE/WRITE_ONCE - nfs_inode_set_delegation() error paths should return the delegation - Use clear_and_wake_up_bit() in nfs_clear_invalid_mapping() and the pNFS code. - Fix the nfs4_alloc_client() error paths to free the IDR allocation - fix folio dereference before NULL check in nfs_inode_remove_request() - Fix delayed delegation return - Fix another state manager race with umount - Fix device leaks on parse failure - Avoid cancelling in-flight I/O during a layout recall if the server doesn't require it - flexfiles: report cancelled I/O as a layout error - flexfiles: fix NULL dereference for NFSv4.0 data servers - Fix incorrect argument passed to nfs4_delete_lease() - Fix several symlink issues resulting from nfs_atomic_open_v23() - Fix an uninitialised variable issue in the NFSv4.1 callback code - fix LAYOUTSTATS send buffer exhaustion Features and cleanups: - NFSv4.2: Allow the server to specify that file data may not be cached - localio: optimise I/O submission when when not doing memory reclaim - localio: Remove duplicate wait code in nfs_local_commit - flexfiles: support loosely coupled NFSv4.x data servers - pNFS: key the data server cache on the NFS version" * tag 'nfs-for-7.3-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (33 commits) NFSv4.1: fix layout segment leak on the pnfs_layout_process() forget path NFSv4/pnfs: key the data server cache on the NFS version NFSv4.2: fix LAYOUTSTATS send buffer exhaustion pNFS: Fix EBUSY check in pnfs_layout_need_return NFSv4.1: zero referring call lists before decoding nfs: fix ENXIO on O_CREAT open of existing symlink over NFSv3 SUNRPC: wait for in-flight client TLS handshake callback NFSv4: Fix incorrect argument passed to nfs4_delete_lease() in nfs4_add_lease() lockd: fix NULL dereference on lockowner allocation failure NFS: fix delegation_hash_table leak when nfs4_server_common_setup() fails NFSv4/flexfiles: support loosely coupled data servers NFSv4/flexfiles: fix NULL dereference for NFSv4.0 data servers NFSv4: pin the superblock for active state owners sunrpc: fix use-after-free in __rpc_clnt_handle_event and __rpc_clnt_remove_pipedir NFS/localio: issue commit inline when not in a memory-reclaim context NFS/localio: remove dead FLUSH_SYNC handling from nfs_local_commit NFS/localio: issue IO inline when not in a memory-reclaim context NFS: Fix delayed delegation return list handling NFS: Verify symlink inode before caching target NFS: fix folio dereference before NULL check in nfs_inode_remove_request() ...
2026-08-26Merge tag 'pm-7.3-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pmLinus Torvalds1-2/+13
Pull more power management updates from Rafael Wysocki: "These fix two issues in the intel_rapl power capping driver, fix a potential issue in the schedutil cpufreq governor on 32-bit systems, fix a runtime PM issue related to failing system suspend, and update the intel_pstate cpufreq driver: - Fix a kernel panic during PMU unbind in the intel_rapl power capping driver and sign-extend the PMU delta on counter wraparound in it to avoid misreporting energy (Sumeet Pawnikar and Yifan Li) - Unblock runtime PM when device prepare fails that was not done by mistake (Shibo Zhu) - Fix possible rate limit overflow on 32-bit systems in the schedutil cpufreq governor (Hui Su) - Consolidate HWP P-states initialization in the intel_pstate cpufreq driver and make that driver avoid using the DESIRED_PERF HWP hint when the Dynamic Efficiency Control (DEC) is enabled in the processor to avoid inconsistent behavior (Rafael Wysocki)" * tag 'pm-7.3-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: powercap: intel_rapl: Fix kernel panic during PMU unbind PM: sleep: Unblock runtime PM when device prepare fails powercap: intel_rapl: Sign-extend the PMU delta on counter wraparound cpufreq: intel_pstate: Avoid using DESIRED_PERF when DEC is enabled cpufreq: intel_pstate: Consolidate HWP P-states initialization cpufreq: schedutil: Fix rate limit overflow
2026-08-26Merge branches 'pm-cpufreq' and 'pm-sleep'Rafael J. Wysocki1-2/+13
Merge additional cpufreq updates and one update related to system sleep for 7.3-rc1: - Unblock runtime PM when device prepare fails that was not done by mistake (Shibo Zhu) - Fix possible rate limit overflow on 32-bit systems in the schedutil cpufreq governor (Hui Su) - Consolidate HWP P-states initialization in the intel_pstate cpufreq driver and make that driver avoid using the DESIRED_PERF HWP hint when the Dynamic Efficiency Control (DEC) is enabled in the processor to avoid inconsistent behavior (Rafael Wysocki) * pm-cpufreq: cpufreq: intel_pstate: Avoid using DESIRED_PERF when DEC is enabled cpufreq: intel_pstate: Consolidate HWP P-states initialization cpufreq: schedutil: Fix rate limit overflow * pm-sleep: PM: sleep: Unblock runtime PM when device prepare fails
2026-08-24locking/lockdep: add sequence counter to held_lockLiam R. Howlett (Oracle)1-7/+51
Add an 8 bit small sequence counter to the held_lock struct to detect if the lock as been dropped and reacquired. This is useful when a data structure depends on a constant locking context, but is not able to detect locking and unlocking of the lock through its own API. Since the __lock_unpin_lock() will no longer detect underflow by casting the unsigned int to a signed int, update the casting code to use a temp variable for calculations using a signed int. Link: https://lore.kernel.org/20260821192627.4085470-3-liam@infradead.org Signed-off-by: Liam R. Howlett (Oracle) <liam@infradead.org> Suggested-by: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Will Deacon <will@kernel.org> Cc: Boqun Feng <boqun.feng@gmail.com> Cc: Waiman Long <longman@redhat.com> Link: https://lore.kernel.org/all/h3tpnj5kzcrxms5picmimtkpg4aypcpip5wbd6bt2rpdj5k7eb@nhtzs3lefrkq/ Cc: Breno Leitao <leitao@debian.org> Cc: Chris Mason <clm@meta.com> Cc: Chuck Lever <cel@kernel.org> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Joe Perches <joe@perches.com> Cc: Rik van Riel <riel@surriel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-24mm: provide vma_[flags_]is_cow_mapping() and remove is_cow_mapping()Lorenzo Stoakes (ARM)1-1/+1
All remaining callers of is_cow_mapping() are invoking it in the form of is_cow_mapping(vma->vm_flags) or an indirected version of this. Therefore, provide a helper - vma_is_cow_mapping() to directly test the VMA. Additionally provide a new helper vma_flags_is_cow_mapping() which performs the check using the new vma_flags_t type, and share this logic between vma_is_cow_mapping() and vma_desc_is_cow_mapping(). With these changes, no callers of is_cow_mapping() remain, so remove it. Also update the userland VMA tests to reflect the change. No functional change intended. [akpm@linux-foundation.org: fix kerneldoc comment typo, per Lorenzo] Link: https://lore.kernel.org/aob1goSSPH6sTN9y@gremlin Link: https://lore.kernel.org/20260813-b4-scalable-cow-virt-pgoff-v5-2-c21581c0c3c8@kernel.org Signed-off-by: Lorenzo Stoakes (ARM) <ljs@kernel.org> Acked-by: David Hildenbrand (Arm) <david@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Deucher <alexander.deucher@amd.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alistair Popple <apopple@nvidia.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Baoquan He <baoquan.he@linux.dev> Cc: Barry Song <baohua@kernel.org> Cc: Boris Brezillon <boris.brezillon@collabora.com> Cc: Byungchul Park <byungchul@sk.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Chris Li <chrisl@kernel.org> Cc: Christan König <christian.koenig@amd.com> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Claudio Imbrenda <imbrenda@linux.ibm.com> Cc: Dave Airlie <airlied@gmail.com> Cc: Dev Jain <dev.jain@arm.com> Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Gregory Price (Meta) <gourry@gourry.net> Cc: Harry Yoo <harry@kernel.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Huang Ray <Ray.Huang@amd.com> Cc: "Huang, Ying" <ying.huang@linux.alibaba.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Clark <james.clark@linaro.org> Cc: Jan Kara <jack@suse.cz> Cc: Jann Horn <jannh@google.com> Cc: Janosch Frank <frankja@linux.ibm.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jiri Olsa <jolsa@kernel.org> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Joshua Hahn <joshua.hahnjy@gmail.com> Cc: Kairui Song <kasong@tencent.com> Cc: Kees Cook <kees@kernel.org> Cc: Kemeng Shi <shikemeng@huaweicloud.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Liam R. Howlett <liam@infradead.org> Cc: Liviu Dudau <liviu.dudau@arm.com> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Marc Rutland <mark.rutland@arm.com> Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org> Cc: Matthew Auld <matthew.auld@intel.com> Cc: Matthew Brost <matthew.brost@intel.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Maxime Ripard <mripard@kernel.org> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Namhyung kim <namhyung@kernel.org> Cc: Naoya Horiguchi <nao.horiguchi@gmail.com> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Nico Pache <npache@redhat.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Pedro Falcato <pfalcato@suse.de> Cc: Peter Xu <peterx@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rakie Kim <rakie.kim@sk.com> Cc: Rik van Riel <riel@surriel.com> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Steven Price <steven.price@arm.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com> Cc: Thomas Zimemrmann <tzimmermann@suse.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: xu xin <xu.xin16@zte.com.cn> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-24Merge tags 'dma-mapping-7.3-2026-08-24' and 'dma-mapping-7.3-2026-08-24-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linuxLinus Torvalds7-326/+798
Pull dma-mapping updates from Marek Szyprowski: - swiotlb: - new configuration option for the default pool size (Jagadeesh Pagadala) - reduce overhead for high watermark tracking (chenhuguanshen) - minor code cleanups and improvements (Vova Sharaienko, Honglei Huang and Marek Szyprowski) - add proper tracking of the shared DMA state through direct, pool and swiotlb paths (Aneesh Kumar K.V) This is important for confidential-computing * tag 'dma-mapping-7.3-2026-08-24' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux: dma/swiotlb: decouple high watermark tracking from CONFIG_DEBUG_FS MAINTAINERS: update tree for DMA MAPPING HELPERS dma/swiotlb: introduce Kconfig option for compile-time default pool size dma-direct: Improve readability of the dma_direct_map_sg() for P2PDMA case iommu/dma: simplify dma_iova_destroy() and drop the free_iova helper dma-coherent: use KiB in DMA allocation logs dma-coherent: fix spacing coding style issue * tag 'dma-mapping-7.3-2026-08-24-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux: (23 commits) swiotlb: remove unused SWIOTLB_FORCE flag dma: swiotlb: handle set_memory_decrypted() failures dma: swiotlb: free dynamic pools from process context dma-direct: rename ret to cpu_addr in alloc helpers dma-direct: select DMA address encoding from __DMA_ATTR_ALLOC_CC_SHARED dma-direct: set decrypted flag for remapped DMA allocations dma-direct: make dma_direct_map_phys() honor DMA_ATTR_CC_SHARED dma-direct: Move dma_direct_map_phys() to dma/direct.c dma-direct: pass attrs to dma_capable() for DMA_ATTR_CC_SHARED checks dma-mapping: make dma_pgprot() honor __DMA_ATTR_ALLOC_CC_SHARED dma: swiotlb: track pool encryption state and honor DMA_ATTR_CC_SHARED dma: swiotlb: pass mapping attributes by reference dma-pool: track decrypted atomic pools and select them via attrs dma-direct: use __DMA_ATTR_ALLOC_CC_SHARED in alloc/free paths dma-mapping: Add internal shared allocation attribute coco: arm64: s390: powerpc: Mark secure guests with CC_ATTR_GUEST_MEM_ENCRYPT dma-direct: swiotlb: handle swiotlb alloc/free outside __dma_direct_alloc_pages s390: Expose protected virtualization through cc_platform_has() swiotlb: Preserve allocation virtual address for dynamic pools dma: free atomic pool pages by physical address ...
2026-08-24workqueue: Fix unbound pool lifetime for pending pwqsYao Kai1-6/+6
KASAN reports a use-after-free of an unbound worker_pool in node_activate_pending_pwq(): BUG: KASAN: slab-use-after-free in _raw_spin_trylock+0x6d/0x120 Read of size 4 at addr ffff8880089ce000 by task kworker/u22:0/318 CPU: 1 UID: 0 PID: 318 Comm: kworker/u22:0 Not tainted 7.2.0 #1 PREEMPT(lazy) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 Workqueue: 0x0 (flush-8:0) Call Trace: <TASK> dump_stack_lvl+0x53/0x70 print_report+0xce/0x610 kasan_report+0xce/0x100 _raw_spin_trylock+0x6d/0x120 pwq_dec_nr_in_flight+0x4b4/0xcb0 process_one_work+0x921/0x11a0 worker_thread+0x4d0/0xd20 kthread+0x2de/0x3c0 ret_from_fork+0x3aa/0x620 ret_from_fork_asm+0x1a/0x30 </TASK> Allocated by task 311: alloc_pwq+0x439/0xca0 apply_wqattrs_prepare+0x75e/0xd10 apply_workqueue_attrs_locked+0x44/0xa0 wq_nice_store+0x350/0x450 Freed by task 0: kfree+0x127/0x3b0 rcu_core+0x523/0x1780 handle_softirqs+0x1b3/0x610 Last potentially related work creation: put_unbound_pool+0x3f3/0x7d0 pwq_release_workfn+0x494/0x8e0 kthread_worker_fn+0x1ff/0x790 Canceling the last inactive work skips pwq_dec_nr_active(), so an empty pwq can remain on pending_pwqs when its refcnt reaches zero. pwq_release_workfn() currently puts the pool before removing that pwq. If this drops the last pool reference, the pool can be RCU-freed while the pwq remains reachable, and node_activate_pending_pwq() may trylock the freed pool->lock. Remove the pwq from pending_pwqs before putting the pool. Fixes: 5797b1c18919 ("workqueue: Implement system-wide nr_active enforcement for unbound workqueues") Cc: stable@vger.kernel.org Signed-off-by: Yao Kai <yaokai34@huawei.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2026-08-24cgroup/cpuset: Preserve boot-isolated CPUs on partition releaseGuopeng Zhang1-10/+29
isolated_cpus tracks CPUs isolated with isolcpus= as well as CPUs in isolated cpuset partitions. When an isolated partition is released, isolated_cpus_update() removes its whole CPU mask. This also clears CPUs which were already isolated at boot. This can be reproduced on a cgroup v2 system booted with isolcpus=domain,15: cd /sys/fs/cgroup echo +cpuset > cgroup.subtree_control mkdir cpuset-repro echo 15 > cpuset-repro/cpuset.cpus echo isolated > cpuset-repro/cpuset.cpus.partition echo member > cpuset-repro/cpuset.cpus.partition cat cpuset.cpus.isolated CPU 15 is absent before the change. It must remain in cpuset.cpus.isolated after the partition is released. Update isolated_cpus one CPU at a time and keep CPUs outside the boot-time domain housekeeping mask isolated. Fixes: c188f33c864e ("cgroup/cpuset: Account for boot time isolated CPUs") Signed-off-by: Guopeng Zhang <zhangguopeng@kylinos.cn> Acked-by: Waiman Long <longman@redhat.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2026-08-24dma-contiguous: fix truncation of numa_cma / cma_pernuma sizes >= 2GAlexander Graf1-7/+9
numa_cma=0:4G reserves nothing at all. dma_numa_cma_reserve() copies the requested size into a local int before handing it to cma_declare_contiguous_nid(), so 0x100000000 truncates to zero and the loop skips the node silently. Both parameters are documented in kernel-parameters.txt as nn[MG], so that is the syntax the documentation invites. Which bits survive decides what a request turns into: 4G, 8G and 16G reserve nothing, 2G, 3G and 6G sign-extend into a size the allocator rejects with a warning, and 5G quietly reserves 1G. It reaches further than those parameters. On a CMA_SIZE_PERNUMA kernel with no per-node parameter, dma_numa_cma_reserve() takes the per-node size from the default area, so a plain cma=4G on a multi-node machine feeds that size through the same local and loses every per-node area. numa_cma_size[] and pernuma_size_bytes are both phys_addr_t, so use it for the local too, and give early_numa_cma() separate variables for the node id and the size while in there. Fixes: d5cae2261b86 ("dma-contiguous: simplify numa cma area handling") Cc: stable@vger.kernel.org Assisted-by: Kiro:claude-opus-5 Signed-off-by: Alexander Graf <graf@amazon.com> Reviewed-by: Feng Tang <feng.tang@linux.alibaba.com> Link: https://lore.kernel.org/r/20260821224252.70640-1-graf@amazon.com Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2026-08-24printk: Don't WARN on kthread_run failure.Tetsuo Handa2-2/+2
Since __kthread_create_on_node() returns -EINTR upon SIGKILL, we should not use WARN_ON() in order to catch kthread_run() failure. Reported-by: syzbot+1ebbc20f223b99446034@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=1ebbc20f223b99446034 Fixes: 5f53ca3ff83b ("printk: Implement legacy printer kthread for PREEMPT_RT") Fixes: 76f258bf3f2a ("printk: nbcon: Introduce printer kthreads") Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Reviewed-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Petr Mladek <pmladek@suse.com> Link: https://patch.msgid.link/76bb4c1c-5d85-4635-b3bb-fc06f292c59e@I-love.SAKURA.ne.jp Signed-off-by: Petr Mladek <pmladek@suse.com>
2026-08-24locking: Revert switching guards to _irq_{disable,enable}()Peter Zijlstra1-6/+6
Revert commit 1b0866874833 ("locking: Switch to _irq_{disable,enable}() variants in cleanup guards"). While the guards are properly nested, not all wrapped code is nice, as already highlighted by that fair.c hunk. Syzbot found another instance of this pattern in posix_timer_delete(), which does spin_unlock_irq()+spin_lock_irq() inside scoped_guard(spinlock_irq). Combined with this patch, that goes sideways most spectacular. Undo this until we've developed stronger tools / debug for such issues. Fixes: 1b0866874833 ("locking: Switch to _irq_{disable,enable}() variants in cleanup guards") Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://patch.msgid.link/20260824105523.GA4121620%40noisy.programming.kicks-ass.net
2026-08-23Merge tag 'scftorture.2026.08.18a' of git://git.kernel.org/pub/scm/linux/kernel/git/rcu/linuxLinus Torvalds1-1/+2
Pull smp_call_function() torture-test updates from Paul McKenney: - Count single_rpc offline failures in statistics output - Make invoker threads actually wait for all threads to start * tag 'scftorture.2026.08.18a' of git://git.kernel.org/pub/scm/linux/kernel/git/rcu/linux: scftorture: Make invoker threads actually wait for all threads to start scftorture: Count single_rpc offline failures in statistics output
2026-08-23Merge tag 'rcu.2026.08.18a' of git://git.kernel.org/pub/scm/linux/kernel/git/rcu/linuxLinus Torvalds17-402/+884
Pull RCU updates from Paul McKenney: "Make expedited grace periods expedite normal RCU callbacks Miscellaneous fixes: - Improve diagnostic output with character task states - Mark accesses to inform KCSAN of concurrency design - Move from kmalloc() to kmalloc_obj() - Documentation updates - Improve handling of RCU deferred quiescent states - Clean up unused function arguments and structure fields - Reduce show_rcu_gp_kthreads() stack space Tasks RCU updates: - Clean up after SRCU re-implementation of Tasks Trace RCU - Mark accesses to inform KCSAN of concurrency design - Add ->lazy_timer status to diagnostic output - Remove an unnecessary memory barrier - Fix a data race, courtesy of KCSAN - Documentation updates - Convert cond_resched_tasks_rcu_qs() from macro to static inline function SRCU updates: - Add Rust helpers for SRCU - Avoid losing queued work at cleanup_srcu_struct() time Torture-test updates: - Preparation work for immediate RCU priority deboosting - Test RCU readers from real interrupt handlers (as opposed to softirq) - Simplify code through use of cpumask_next_wrap() - Improve diagnostic output with character task states - Add rcutorture.nwriters parameter to allow lightweight stall testing, and rcutorture.stall_only to make doing so easier - Test an RCU Tasks Trace grace period implying an RCU grace period - Make RCU Tasks Trace torturing track reader batches - Fix a data race, courtesy of KCSAN - Plug a shuffle_tmp_mask memory leak on kthread spawn failure" * tag 'rcu.2026.08.18a' of git://git.kernel.org/pub/scm/linux/kernel/git/rcu/linux: (59 commits) rcu: Add closing parenthesis in comment in rcu_read_unlock_strict() rcutorture: Make {,s}rcu_read_delay() better handle forward-progress testing rcutorture: Announce declining to forward-progress test torture: Don't leak shuffle_tmp_mask when shuffler kthread fails to start rcutorture: Use this_cpu_inc() for rcu_torture_count[] and rcu_torture_batch[] rcutorture: Make RCU Tasks Trace track Reader Batches rcutorture: Test RCU Tasks Trace GP implying RCU GP rcutorture: Add a stall_only module parameter rcutorture: Add nwriters module parameter rcutorture: Use task_state_to_char() for task-state reporting rcutorture: Use cpumask_next_wrap() in rcu_torture_preempt() rcutorture: Test RCU readers from hardware interrupt handlers rcutorture: Check for immediate deboosting at reader end srcu: Queue sdp->work when the delay timer is successfully deleted rcu-tasks: Convert cond_resched_tasks_rcu_qs() to static inline rcu-tasks: Fix some comments for call_rcu_tasks() and call_rcu_tasks_rude() rcu-tasks: Rename tasks_rcu_exit_srcu_stall_timer to tasks_rcu_exit_stall_timer rcu: Mark interrupts-enabled accesses to rdp->cpu_no_qs.s rcu: Reduce stack usage in show_rcu_gp_kthreads() rcu: Mark accesses to ->rcu_urgent_qs and ->rcu_need_heavy_qs ...
2026-08-23Merge tag 's390-7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linuxLinus Torvalds1-4/+3
Pull s390 updates from Vasily Gorbik: - Add a cpuidle driver with polling and enabled wait states using the existing CPU idle infrastructure and idle governor to improve latency for frequent sleep/wakeup cycles. Remove the obsolete tick delay heuristic and generic arch_needs_cpu() hook. Add the corresponding driver entry to MAINTAINERS - Add kCFI support using the generic support provided by Clang - Enable Clang CONTEXT_ANALYSIS for various architecture code and for char, PCI, CIO and virtio drivers. Add required lock annotations, exclude unsupported mm helpers and remove conditional PCI locking - Fix secure storage access exception handling and reintroduce DCACHE_WORD_ACCESS previously removed as a workaround - Fix cpum_cf perf crashes when CPUs are brought online while per-task events are active. Allocate and remove per-CPU counter data from CPU hotplug callbacks - Fix a deadlock when an s390dbf debug area is unregistered while one of its debugfs files is being written to - Fix MVIY_PERCPU() with binutils older than 2.39, where an assembler macro silently omitted an instruction needed to repair interrupted operations after CPU migration - Remove/replace cond_resched() calls which are no-ops with the supported s390 preemption models - Fix AP queue depth and maximum message length decoding according to the architecture. Current hardware is not affected, but future hardware could report values which were handled incorrectly - Reflect the configured CPU state in cpu_enabled_mask so deconfigured CPUs are not presented as available for onlining - Restore the vDSO GNU_EH_FRAME program header which was lost when the build switched to direct linker invocation, and mark it read-only - Add SCLP action qualifiers used by Spyre for card initialization, recoverable error and telemetry reporting - Move KMSAN interrupt flag helpers out of line to fix -Wstatic-in-inline build warnings - Use level-specific page table entry accessors for hugetlb entries and ptep_get() when accessing crashed kernel memory in kdump - Make forced AP bus rescans killable so that a user process blocked behind an ongoing scan can still be terminated with SIGKILL - Rework pkey ioctl error paths to remove duplicated cleanup code and avoid freeing error pointers - Allow the protected guest SWIOTLB buffer to be allocated outside the first 2GB. Also enable dynamic SWIOTLB growth and the coherent atomic pool fallback to improve I/O behavior when the initial pool is exhausted - Add program check statistics and spinlock contention tracepoints. Increase the lockdep chain capacity to keep lockdep enabled for complex code paths such as btrfs - Simplify IPL, trap and syscall code and remove the obsolete unistd_32.h generation entry * tag 's390-7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (59 commits) s390/percpu: Fix MVIY_PERCPU() with older binutils s390/debug: Fix deadlock during unregister s390/cpum_cf: Handle CPU hotplug via prepare/dead callbacks s390: Enable CONTEXT_ANALYSIS for various directories s390/mm: Add __context_unsafe() attribute to gmap helper functions s390/mm: Add __context_unsafe() attribute to do_secure_storage_access() s390/sysinfo: Add context analysis attributes s390/irqflags: Add out-of-line definitions of arch_local_irq_*() for KMSAN s390/virtio: Enable CONTEXT_ANALYSIS s390/cio: Enable CONTEXT_ANALYSIS s390/vfio_ccw: Add __must_hold() attribute to vfio_ccw_sch_quiesce() s390/pci: Enable CONTEXT_ANALYSIS s390/pci: Rework __zpci_event_availability() to remove conditional locking s390/pci: Rework __zpci_event_error() to remove conditional locking s390/char: Enable CONTEXT_ANALYSIS s390/con3215: Add __must_hold() attribute to raw3215_make_room() s390/ap: Fix MAPML computation s390/cio: Remove cond_resched() calls s390: Remove cond_resched() calls KVM: s390: Remove cond_resched() calls ...
2026-08-23Merge tag 'liveupdate-v7.3-rc1-20260823' of git://git.kernel.org/pub/scm/linux/kernel/git/liveupdate/linuxLinus Torvalds4-146/+414
Pull more liveupdate updates from Mike Rapoport: "Make boot time huge page allocation work nicely with kexec handover. Today allocation of gigantic pages in HugeTLB cannot work reliably with kexec handover (KHO): - HugeTLB allocates gigantic pages using memblock and autoscaling of KHO scratch accounts for these allocations. When gigantic pages occupy half of the memory of more, KHO fails to allocate its scratch memory. - After kexec handover, memblock allocations exclusively use KHO scratch that is not supposed to contain preserved memory. This essentially blocks preservation of HugeTLB with gigantic pages. Extend early memory pools available for KHO kernel with areas that are guaranteed not to contain preserved memory" * tag 'liveupdate-v7.3-rc1-20260823' of git://git.kernel.org/pub/scm/linux/kernel/git/liveupdate/linux: (21 commits) kho: exclude hugetlb memory from scratch size calculation memblock: add memblock_reserved_hugetlb_size() memblock: make HugeTLB bootmem allocation work with KHO memblock: always include KHO headers kho: extend scratch mm/mm_init: don't rely on memblock to get KHO scratch migratetype kho: initialize preserved memory map radix tree earlier kho: initialize kho_scratch pointer earlier in boot kho: expose kho_scratch_overlap() to kexec_handover.h kho: add kho_radix_init_tree() kho: allow destroying KHO radix tree kho: allow early-boot usage of the KHO radix tree kho: add data argument to radix walk callback kho: add callback for table pages kho: add a struct for radix callbacks kho: move all memory retrieval logic to kho_mem_retrieve() kho: store incoming radix tree in kho_in kho: disallow wide keys in radix tree kho: make radix max key width more obvious kho: generalize radix tree APIs ...
2026-08-23Merge tag 'mm-nonmm-stable-2026-08-22-16-57' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mmLinus Torvalds8-129/+108
Pull non-MM updates from Andrew Morton: - "ocfs2/dlm: bound peer-controlled lengths in the o2dlm" (Bryam Vargas) Validate and bound all input lengths and count fields in the o2dlm migration and recovery receive handlers to prevent memory corruption and kernel panics from malformed cluster messages - "ocfs2: validate xattr entry bounds" (Cen Zhang) Validate OCFS2 extended attribute entry name and value bounds during metadata reads to prevent out-of-range memory accesses during retrieval or listing operations. - "taskstats: fix cgroupstats invalid fd handling and add selftests" (Yiyang Chen) Return -EBADF when cgroupstats receives an invalid file descriptor to prevent caller hangs and misleading success ACKs. Add a kselftest to validate valid cgroup v1 queries and verify proper error handling across different Netlink flag combinations. - "misc lib/raid/ improvements v2" (Christoph Hellwig) Improve benchmark-based algorithm selection for the XOR and RAID6 libraries, add KUnit benchmark tests, and cleanup minor implementation details. - "ocfs2: cluster: o2hb_region_pin() fixes" (Joseph Qi) Fix sleeping-in-atomic, lock order inversion and error-path cleanup bugs in o2hb_region_pin() by releasing o2hb_live_lock across sleeping configfs_depend_item() calls and using unlocked variants from callback context. Ensure failed pin attempts properly decrement user counts and unpin partially initialized heartbeat regions to prevent memory leaks and unprotected states. - "lib/ucs2_string.c: fix out-of-bounds read in ucs2_strnlen()" (Vincent Mailhol) Fix an off-by-one which could cause an out-of-bounds read. - "ocfs2: harden heartbeat teardown races" (Cen Zhang) Fix two OCFS2 heartbeat/o2net teardown races found by KASAN. - "taskstats: tidy up the cpumask command path" *Bradley Morgan) make two small cleanups in kernel/taskstats.c. - "ocfs2: validate active orphan slots during inode read" (ZhengYuan Huang) Validate active ordinary and append-DIO orphan slots read from OCFS2 dinodes at the metadata boundary to prevent corrupted slot indices from causing out-of-bounds array accesses. - "ocfs2: bound-check both readdir re-validation scans" (Zhan Xusheng) Enforce strict boundary checks on directory entry record lengths and offset calculations during OCFS2 directory re-scans to prevent out-of-bounds memory reads and directory position corruption. * tag 'mm-nonmm-stable-2026-08-22-16-57' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (95 commits) mailmap: fix bouncing address for Taniya Das ocfs2: bound-check dir entries in the inline-data re-validation scan ocfs2: bound-check dir entries in the readdir re-validation scan squashfs: avoid thundering-herd cache wakeups prctl: fix PR_SET_MM_AUXV losing the forced AT_NULL terminator mailmap: update email address for Linfeng Sun lib/interval_tree: fix allocation warning messages checkpatch: add NOKPROBE_SYMBOL to the whitelist of lines that can occur immediately after functions Squashfs: check block offset is not negative signal: factor out the kernel reserved si_code check ocfs2: fix readdir position truncation on 32-bit kernels ocfs2: fix cached cluster count after suballocator reclaim ocfs2: fix circular locking dependency in ocfs2_init_acl() ocfs2: validate DIO orphan slot during inode read ocfs2: validate orphan slot during inode read selftests/prctl: fix non-anonymous VMA mapping in set-anon-vma-name test MAINTAINERS: add IRC and patchwork for LTP include/linux/list.h: mark list_add and __list_add as __always_inline tools/mm: prevent page_owner_sort from truncating input hung_task: update DETECT_HUNG_TASK_BLOCKER Kconfig help ...
2026-08-22Merge tag 'sched-urgent-2026-08-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-1/+6
Pull scheduler fixes from Ingo Molnar: - Add missing cpus_read_lock locking to rebuild_sched_domains() (Sebastian Andrzej Siewior) - Fix division by zero bug in tg_cpus() that can be triggered with empty cpusets (Jake Steinman) * tag 'sched-urgent-2026-08-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/fair: Floor tg_cpus() at 1 sched/topology: Add a cpus_read_lock to rebuild_sched_domains()
2026-08-22Merge tag 'locking-urgent-2026-08-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds6-70/+196
Pull futex fixes from Ingo Molnar: - Enforce that the private futex owner shares the mm when attaching (Kyle Zeng, Thomas Gleixner) - Fix race on the initial mm->futex.phash.ref allocation (Hyunwoo Kim) - Fix might_sleep() warning in futex_pivot_pending() (Peter Zijlstra) * tag 'locking-urgent-2026-08-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: futex: Fix might_sleep() warning in futex_pivot_pending() futex: Fix race on the initial mm->futex.phash.ref allocation futex: Clean up the redundant exit/exec functions futex/pi: Plug private futex exec() race futex: Sanitize and document task_struct::futex::state transitions futex/pi: Reject cross-mm private futex owners
2026-08-22Merge tags 'core-urgent-2026-08-22' and 'timers-urgent-2026-08-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-0/+1
Pull timer fixes from Ingo Molnar: - Fix timer debugobjects state corruption on CPU offlining (Thomas Gleixner) - Fix ARM get_cycles() regression causing boot hangs on certain ARM configs (Nathan Chancellor) * tag 'core-urgent-2026-08-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: timer: Keep debugobjects state consistent in migrate_timer_list() * tag 'timers-urgent-2026-08-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: ARM: Fix get_cycles() after delay_read_timer() conversion
2026-08-22tracing: Fix use-after-free in trace_pipe read on sub-buffer order changeDeepanshu Kartikey1-0/+3
Writing to buffer_subbuf_size_kb calls ring_buffer_subbuf_order_set(), which frees every sub-buffer of the ring buffer, including the reader page, and replaces them with newly allocated ones. Readers of trace_pipe hold pointers into those pages. ring_buffer_peek() looks up an event under cpu_buffer->reader_lock but returns the event pointer after dropping the lock, and peek_next_entry() then calls ring_buffer_event_length() and ring_buffer_event_data() on it. If the sub-buffer order is changed in that window, the reader dereferences freed memory: BUG: KASAN: use-after-free in ring_buffer_peek+0x3e0/0x430 Read of size 1 at addr ffff88802a4cf010 by task syz-executor989/6002 Freed by: free_buffer_page kernel/trace/ring_buffer.c:398 [inline] ring_buffer_subbuf_order_set+0x1325/0x18e0 kernel/trace/ring_buffer.c:7444 buffer_subbuf_size_write+0x182/0x280 kernel/trace/trace.c:8221 Take trace_access_lock(RING_BUFFER_ALL_CPUS) around the order change. This is the lock trace_pipe readers already hold across their entire peek-and-print loop, so the swap can no longer race with a reader that is dereferencing a peeked event. Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260817140655.5694-1-kartikey406@gmail.com Fixes: f9b94daa542a ("ring-buffer: Set new size of the ring buffer sub page") Reported-by: syzbot+685955db58555575fdd2@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=685955db58555575fdd2 Tested-by: syzbot+685955db58555575fdd2@syzkaller.appspotmail.com Reviewed-by: Bradley Morgan <include@grrlz.net> Signed-off-by: Deepanshu Kartikey <kartikey406@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-08-22tracing: Fix crash passing ERR_PTR to kthread_stop()Hui Su1-0/+2
event_test_stuff() calls kthread_run() and unconditionally passes the returned task_struct pointer to kthread_stop(). kthread_run() returns an error pointer such as ERR_PTR(-ENOMEM) when kthread creation fails, for example under memory pressure during the boot-time event self-test. kthread_stop() then dereferences the invalid pointer, crashing the kernel. Check the result of kthread_run() before passing it to kthread_stop(). Use WARN_ON() so that a failure to create the self-test thread does not go unnoticed, matching the ring-buffer self-test fix in commit 91542863abad ("ring-buffer: Fix crash passing ERR_PTR to kthread_stop()"). Cc: stable@vger.kernel.org Fixes: e6187007d6c3 ("tracing/events: add startup tests for events") Link: https://patch.msgid.link/20260817120642.668375-3-sh_def@163.com Signed-off-by: Hui Su <sh_def@163.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-08-22tracing: Fix use-after-free with same-name named triggersHui Su1-1/+3
When two hist triggers on different events are registered with the same name=, the second one reuses the first as named_data. Both are added to tr->hist_vars by save_hist_vars() during event_hist_trigger_parse(), because save_hist_vars() is called before event_trigger_register() while the named reuse is only detected later, in hist_register_trigger(). In the named-data branch hist_register_trigger() then frees the second histogram's hist_data via destroy_hist_data(), but never removes its tr->hist_vars list entry, leaving a dangling pointer and leaking the trace_array reference it holds. A later hist trigger that references a variable makes find_var_file() walk tr->hist_vars and dereference the freed hist_data. The bug is reproducible from userspace by writing three hist triggers to tracefs: cd /sys/kernel/tracing echo 'hist:keys=common_pid:x=common_pid:name=mh' > events/sched/sched_switch/trigger echo 'hist:keys=common_pid:x=common_pid:name=mh' > events/sched/sched_process_fork/trigger echo 'hist:keys=common_pid:vals=$x' > events/sched/sched_process_exit/trigger The third write panics the kernel: BUG: KASAN: slab-use-after-free in find_var_file.part.0+0x272/0x290 Read of size 8 at addr ffff888001f8a0e0 by task sh/1 CPU: 1 UID: 0 PID: 1 Comm: sh Tainted: G D N Call Trace: find_var_file.part.0 find_event_var parse_atom parse_expr __create_val_field event_hist_trigger_parse trigger_process_regex event_trigger_write vfs_write ksys_write do_syscall_64 entry_SYSCALL_64_after_hwframe Allocated by task 1: event_hist_trigger_parse Freed by task 1: hist_register_trigger+0x618/0xa30 event_hist_trigger_parse The buggy address belongs to freed 2048-byte region Oops: general protection fault ... RIP: find_var_file.part.0 Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b Fix by removing the hist_data from tr->hist_vars and releasing the trace_array reference in the named-data branch of hist_register_trigger() before freeing the hist_data. Cc: stable@vger.kernel.org Fixes: 6f86bdeab633 ("tracing: Fix bad hist from corrupting named_triggers list") Link: https://patch.msgid.link/20260816100427.33642-3-sh_def@163.com Signed-off-by: Hui Su <sh_def@163.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-08-22sched_ext: Fix spurious aborts in scx_bpf_dsq_move() on ownership change racesTejun Heo1-8/+13
scx_dsq_move() verifies that the task belongs to the calling scheduler before taking any locks and aborts the scheduler on mismatch. The task can lose the sched association at any point: It can run and fully exit, which clears the association, or get rehomed to a different sub-sched. Both are benign races, but the early ownership check escalates them into scheduler aborts. Move the ownership check below the cursor-lost check. Every ownership change dequeues the task first, so a task that is still on the iterated DSQ under the lock while owned elsewhere indicates a genuine violation and should abort. Also fix two stale comments still referencing sched_ext_free(), which has been renamed to sched_ext_dead(). Fixes: bb4d9fd55158 ("sched_ext: scx_dsq_move() should validate the task belongs to the right scheduler") Signed-off-by: Tejun Heo <tj@kernel.org>
2026-08-22tracing: Fix logged instance name on creation failureVincent Donnefort1-1/+2
When boot instance creation fails, the kernel incorrectly logs "(null)" as the instance name because strsep() consumes curr_str entirely during parsing. Print the properly parsed name variable instead. And while at it log the error code. Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260807085423.4175161-1-vdonnefort@google.com Fixes: cb1f98c5e574 ("tracing: Add creation of instances at boot command line") Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Vincent Donnefort <vdonnefort@google.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-08-21Merge tag 'livepatching-for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/livepatching/livepatchingLinus Torvalds1-12/+22
Pull livepatching updates from Petr Mladek: - Move consistency checks to catch missing func->old_name before the first access - Allow to run livepatching selftests from top-level directory * tag 'livepatching-for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/livepatching/livepatching: kbuild: unset sub_make_done before calling kselftest build system livepatch: Fix NULL pointer dereference in klp_find_func()
2026-08-21Merge tag 'modules-7.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/modules/linuxLinus Torvalds6-117/+125
Pull module updates from Petr Pavlu: - Remove unnecessary module::args. Nowadays, no parameter-handling code points into the module::args buffer. The last user of module::args in xtensa/simdisk is updated and the data is then removed - Add Rust support for boolean parameters. This will initially be used by the Rust null block driver - Fix clearing the current charp parameter value when setting a new one fails due to an allocation failure - Improve the debugging code for kmod (request_module()) duplicates. Fix a potential use-after-free when waiting on a duplicate request and make several general improvements to the code - Fix the symbol size returned when looking up a data symbol through kallsyms - Smaller fixes and cleanups * tag 'modules-7.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/modules/linux: params: fix charp corruption on allocation failure module: validate string table section types module/dups: Clean up includes module/dups: Use strcmp() to compare module names module/dups: Use scope-based cleanup helpers module/dups: Avoid unnecessary kmod_dup_req allocations module/dups: Fix use-after-free in kmod_dup_req lifetime handling module/dups: Inform duplicate requests about the result directly rust: module_param: support bool parameters rust: module_param: return value by copy from `value` module: Remove unnecessary module::args xtensa/simdisk: Avoid referring to module::args module: Remove unused DISCARD_EH_FRAME definition from module.lds.S module: procfs: use matching type for accumulator in module_total_size() module: use strscpy() to copy module names in stats and dup tracking params: fix path of /sys/module/XYZ/parameters/ in comment module/kallsyms: fix nextval for data symbol lookup
2026-08-21Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdmaLinus Torvalds1-12/+59
Pull RDMA updates from Jason Gunthorpe: "About the normal size, still a lot of AI bug fixes and so on, but some interesting new functionality too: - Assorted locking, bounds-checking, cleanup, and error-path fixes across UCMA/CMA, bng_re, bnxt_re, cxgb4, EFA, ERDMA, HFI1, HNS, ionic, iRDMA, mlx4/mlx5, RXE, SIW, SRP/SRPT, and iSER target. - netlink report for max # of supported resources - get_zeroed_page()/etc removal - Robust udata for ionic - Allow unique RDMA device names per network namespace - Completion counters and v2 admit queue support for EFA - UC QP support for MANA - Completion timestamps for ionic - Harden uverbs data validation and resource lifetime handling, fixing several core use-after-free conditions. - bnxt_re toggle-page ownership and lifetime bug fixes - dmabuf SRQ support for mlx5" * tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: (160 commits) RDMA/ucma: Allow path records to exactly fit the output buffer RDMA/uverbs: Guard legacy bundles without method_elm RDMA/efa: Add support for 128B admin v2 SQ entry RDMA/efa: Generalize the admin SQ RDMA/efa: Decouple admin command payload from admin header RDMA/rxe: Fix OOB in free_rd_atomic_resources() RDMA/cma: Fix WARNING in res_to_rt RDMA/cxgb4: Free debugfs on registration failure RDMA/cxgb4: Cancel reg_work before freeing device on remove RDMA/ucma: Lock the handler in ucma_set_ib_path() RDMA/ucma: Lock the handler in ucma_write_cm_event() RDMA/erdma: restrict the driver to little-endian systems RDMA/ionic: Embed counter driver data in rdma_counter allocation RDMA/ionic: Cap eq_count to the eth driver's interrupt vector budget RDMA/siw: Fix use-after-free in siw_accept() IB/isert: post the full-feature receive buffers after session registration IB/isert: delay the final Login Response until the session is registered RDMA/srp: fix heap information leak on a truncated SRP_CRED_REQ RDMA/erdma: Hold QP references for AE and CM processing RDMA/erdma: Hold CQ references when processing EQ events ...