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2026-09-06Merge tag 'trace-v7.3-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fixes from Steven Rostedt: - Fix several tracefs files that did not take the trace_array reference A trace instance can be created and destroyed in the tracefs "instances" directory via mkdir and rmdir respectively. The instance is represented by a trace_array descriptor. Most tracefs files pass the trace_array as the private data of the inode to the open/read/write functions. Since there is no locking between the time a task opens a file and the deletion of the instance (and the freeing of the trace_array), each open needs to get a reference to the trace_array and each close must remove it. An instance can't be removed if there's any reference taken on its trace_array. The open function uses trace_array_get() that takes a lock (preventing removal of instances) and iterates the list of all existing trace_arrays and if it finds a match, it takes the reference and releases the lock. If it doesn't find a match, it causes the open to return -ENODEV. There were some added files that did not take the trace_array reference on open that needed to be fixed. Sashiko also correctly pointed out that there were some files that took an address of an field or element of the trace_array which had a pointer back to the trace_array to take its reference on open. But this leaves a slight race between referencing this element to get the trace_array as the element itself could be freed. To solve this, some helper functions were created to look for trace_arrays with this field or element in the search so that the element did not have to be dereferenced before the trace_array's reference was taken. - Add a lock around ftrace_ops initialization When a ftrace_ops is first used by ftrace, some internal initialization is performed on the ops. But if multiple tasks were calling functions that did this initialization, it could race and perform doing the initialization more than once, corrupting the internal data. Add a lock in the initialization code to prevent this from happening. - Fix splice reads on mmapped buffers The logic in the ring buffer splice code for mmapped buffers is supposed to do a copy of the memory as the mapped buffers can't be given to splice. But there was an if statement within the copy code that would return a -1 if a request for a full page was done and it wasn't a partial read. This is because this logic was written before mmapped buffers existed and this case didn't make sense at the time. For mmapped buffers it makes perfect sense and by returning early can drop a lot of pages unnecessarily. - Have the persistent ring buffer validation check nr_subbufs Sashiko reported that the validation code was relying on the saved nr_subbufs to match the calculated nr_pages + 1 and if they were off, that the code could cause corruption. Sashiko is correct, and the saved nr_subbufs should be validated before assuming it is correct. - Do not allow more than one instance with the same name on cmdline If an admin were to add more than one trace instances with the same name they all would be created, but only the first one would be accessible via tracefs. This used to not be allowed but some restructuring of code has since made it possible. - Fix the race between subbuf resize and trace_pipe_raw readers If a task was reading trace_pipe_raw while another task was changing the ring buffer subbuf size, it could crash the reader. The trace_pipe_raw readers do get their own copy of the page from the buffer, but the code needs some restructuring to not have the resize of the subbuffers cause issues. - Cap the size of the mapped (static) ring buffer nr_pages The meta data used for ring buffer mapped buffers is 32 bit in size. A normal ring buffer could (in theory) have more than 4 billion pages. But this is not allowed by mapped buffers, so enforce it. * tag 'trace-v7.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: ring-buffer: Use a macro for static buffer bits tracing: Fix comment in tracing_buffers_splice_read() ring-buffer: Prevent truncation of nr_pages / nr_subbufs ring-buffer: Cap static ring buffer nr_pages tracing: Fix subbuf resize races with trace_pipe_raw readers tracing: Fix to avoid creating trace instances with duplicate names ring-buffer: Add checking nr_subbufs to persistent ring buffer validation ring-buffer: Allow splice reads on static buffers tracing: Take trace_array reference when opening options file ftrace: Synchronize the initialization of ftrace_ops ftrace: Take trace_array reference before accessing its ftrace_ops tracing: Have show_event_filters/triggers files take trace array ref
2026-09-06Merge tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpfLinus Torvalds
Pull bpf fixes from Alexei Starovoitov: "This mainly contains verifier fixes that address bugs reported by Nicholas Carlini. - Fix incorrect non-NULL inference in pointer comparisons: pointer types that may be NULL at runtime, pointers with unbounded offsets, JMP32 comparisons with zero, and imprecise zero registers (Eduard Zingerman) - Fix precision tracking for half-dead zero spills, ld_abs/ld_ind implicit subprog exit, bpf_loop() callbacks, linked scalar ids and NULL call arguments (Eduard Zingerman) - Reject BPF_PSEUDO_FUNC reference to the main program, fix zero extension of arena 32-bit cmpxchg, don't rewrite bpf_fastcall patterns entered by a jump (Eduard Zingerman) - Fix percpu map update and BPF_F_CPU validation with sparse CPU IDs (Hui Su) - Fix NULL-ptr-derefs in bpf_snprintf_btf() for void and VAR types, and reject key-less BTF for hash maps (Jiayuan Chen) - Various fixes (Kumar Kartikeya Dwivedi): - Fix out-of-bounds access in disassembler on invalid LDSX instruction - mark siginfo of signal tracepoints as scalar and sched_process_wait argument as nullable - mark faultable stack helpers as sleepable - reject tail calls and legacy packet loads from callbacks - enforce rbtree callback lock restrictions for resilient locks - require MEM_PERCPU for percpu kptr stores - clear NON_OWN_REF after RCU protection ends - mark NULL kptr stores precise - preserve inner map identity in callback frames - reject non-scalar bpf_loop() iteration counts - Fix trampoline allocation slowdown on x86 by using EXECMEM_MODULE_DATA (Mike Rapoport) - Keep bpf_refcount_acquire() nullable for borrowed RCU kptrs and reject untrusted allocated-object pointers (Ning Ding) - Fix special fields handling in recycled rhtab elements (Nuoqi Gui, Yuan Chen)" * tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf: (86 commits) bpf, riscv: Make arena support depend on ZACAS selftests/bpf: Test pointer bpf_loop iteration count rejection bpf: Reject non-scalar bpf_loop iteration counts bpf: use mark_arg_precision() in check_mem_size_reg() bpf: propagate mark_chain_precision() errors out of loop_flag_is_zero() selftests/bpf: precision of a NULL global subprogram BTF_ID argument bpf: mark a NULL BTF_ID argument of a global subprogram precise selftests/bpf: precision of a NULL kfunc argument bpf: mark a NULL kfunc argument precise selftests/bpf: precision of a NULL global subprogram memory argument bpf: mark a NULL memory argument of a call precise selftests/bpf: precision of a NULL helper argument bpf: mark a NULL call argument precise selftests/bpf: Test inner map identities in callbacks bpf: Preserve inner map identity in callback frames selftests/bpf: Test imprecise scalar kptr stores bpf: Mark NULL kptr stores precise selftests/bpf: Test rhtab kptr cancellation semantics bpf: Cancel special fields when recycling rhtab elements selftests/bpf: Test timer field on recycled rhtab element ...
2026-09-06Merge tag 'locking-urgent-2026-09-06' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking fixes from Ingo Molnar: - Fix a softirq processing delay bug in local_interrupt_disable(), which should mostly only affect the Rust runtime (Boqun Feng) - Remove the hardirq_disable_count() function which caused the previous bug and is now unused & unnecessary (Boqun Feng) - lockdep: Invalidate stale class_cache entries for zapped classes (Eric Dumazet) - Fix rt_mutex specific futex scheduling helpers (Sebastian Andrzej Siewior) - Fix rcuwait use-after-free race during futex requeue PI (Yao Kai) * tag 'locking-urgent-2026-09-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: futex: Prevent rcuwait use-after-free during requeue PI futex: Provide rt_mutex_.*_schedule() equivalents for futex scheduling locking/lockdep: Invalidate stale class_cache entries for zapped classes preempt: Remove hardirq_disable_count() interrupt: Disable interrupt before modifying hardirq_disable counter
2026-09-06Merge tag 'irq-urgent-2026-09-06' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull IRQ subsystem fixes from Ingo Molnar: - Revert a commit to the mbigen irqchip driver that caused a regression on two-port Hi1616 chips (Caina) - Fix a too-long-preemption-off bug in the stm32mp-exti irqchip driver, caused by a time unit ambiguity & mismatch (Ju Nan) - Remove the now completely unused irq_domain_add_linear() inline function (Jiri Slaby) * tag 'irq-urgent-2026-09-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: irqchip/stm32mp-exti: Fix the unit of the hwspinlock timeout Revert "irqchip/mbigen: Fix mbigen node address layout" irqdomain: Delete irq_domain_add_linear()
2026-09-05bpf: Reject non-scalar bpf_loop iteration countsKumar Kartikeya Dwivedi
bpf_loop() declares its nr_loops argument as ARG_ANYTHING. Privileged programs may pass pointer values to such arguments, so check_func_arg() lets a pointer-valued R1 reach the helper-specific checks. Since commit bb124da69c47 ("bpf: keep track of max number of bpf_loop callback iterations"), the verifier marks R1 precise and reads its upper bound to limit callback simulation. Precision backtracking only accepts scalar registers, so passing a pointer instead triggers the "backtracking misuse" verifier warning. Kernels with panic_on_warn enabled subsequently panic. Introduce ARG_SCALAR for helper arguments that only accept scalar values and use it for bpf_loop() nr_loops. Generic helper argument validation then rejects pointers before loop inlining and precision processing. Fixes: bb124da69c47 ("bpf: keep track of max number of bpf_loop callback iterations") Reported-by: syzbot+7b47f87674e9a1569110@syzkaller.appspotmail.com Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Link: https://patch.msgid.link/20260905014735.1452988-2-memxor@gmail.com Closes: https://lore.kernel.org/bpf/6a9ad24c.b5d4176b.238c3e.0001.GAE@google.com/ Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
2026-09-05Merge tag 'driver-core-7.3-rc2' of ↵graftedLinus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core Pull driver core fixes from Danilo Krummrich: - Fix kernfs listxattr() not returning security xattr names (e.g. SELinux labels) when the kernfs node has no allocated kernfs_iattrs - Fix silent truncation of IRQ vector indices in the Rust PCI abstractions - Don't select OF from DRIVER_PE_KUNIT_TEST; skip the test when OF is disabled instead of silently enabling extra kernel functionality - Russ Weight is retiring from kernel development; update the Firmware Loader sysfs contact to the driver-core mailing list, add a CREDITS entry for Firmware Upload, and update MAINTAINERS accordingly * tag 'driver-core-7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core: MAINTAINERS: Remove Russ Weight from Firmware Loader CREDITS: Add CREDITS entry for Firmware Upload firmware_loader: Change contact for sysfs nodes rust: pci: reject IRQ vector indices that do not fit in u32 kernfs: preserve security xattrs without allocating iattrs drivers: base: test: DRIVER_PE_KUNIT_TEST should not select OF
2026-09-04tracing: Fix subbuf resize races with trace_pipe_raw readersVincent Donnefort
Concurrent subbuffer resizes may crash trace_pipe_raw readers or leak uninitialized memory to userspace due to stale size values. Modify ring_buffer_alloc_read_page() to handle the resizing of an existing buffer_data_read_page if necessary and add a new ring_buffer_read_page_size(). This new function enables ring-buffer buffer_data_read_page users to not call the racy ring_buffer_subbuf_size_get(). This makes the spare_size member of ftrace_buffer_info redundant. Finally, handle buffer_data_read_page/reader_page order discrepancy in ring_buffer_read_page(). On a mismatch simply copy manually the data to the buffer_data_read_page. Link: https://lore.kernel.org/all/20260817140812.2C7D41F00A3A@smtp.kernel.org/ Link: https://patch.msgid.link/20260904164450.1345852-3-vdonnefort@google.com Fixes: bce761d75745 ("ring-buffer: Read and write to ring buffers with custom sub buffer size") Signed-off-by: Vincent Donnefort <vdonnefort@google.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-09-04bpf: Reject untrusted allocated-object pointersNing Ding
When the final RCU read-side critical section ends, a local kptr is demoted to PTR_UNTRUSTED but retains MEM_ALLOC. The pointer may be NULL or may refer to an object whose lifetime is no longer protected. type_is_ptr_alloc_obj() nevertheless recognizes any PTR_TO_BTF_ID with MEM_ALLOC as a live allocated object. In particular, a refcount-only local kptr never carries NON_OWN_REF, so it still passes the bpf_refcount_acquire() argument check after RCU protection ends. The kfunc can then dereference NULL or stale memory. Make type_is_ptr_alloc_obj() reject PTR_UNTRUSTED pointers. Since type_is_non_owning_ref() is based on the same predicate, graph kfunc arguments obey the same live-object requirement. Fault-protected reads of the demoted pointer remain valid: writes are already rejected, and read fixups use bpf_may_fault_on_deref() rather than this predicate. Fixes: 1b12171533a9 ("bpf: Mark direct ld of stashed bpf_{rb,list}_node as non-owning ref") Reported-by: Nicholas Carlini <npc@anthropic.com> Suggested-by: Nicholas Carlini <npc@anthropic.com> Signed-off-by: Ning Ding <dingning04@gmail.com> [ kkd: Rewrote commit log ] Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Link: https://lore.kernel.org/r/20260904084325.52250-8-memxor@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-09-04selftests/bpf: Reject graph kptr use after RCU unlockgraftedKumar Kartikeya Dwivedi
Add a sleepable verifier test that loads a graph-node local kptr in an explicit RCU read-side critical section, then passes its node to bpf_rbtree_remove() after the section ends. Before the verifier fix, the stale NON_OWN_REF flag makes the node look like a live borrowed reference and the program is accepted. After the fix, the pointer is demoted without NON_OWN_REF and the graph kfunc argument is rejected. Also exercise a graph kptr loaded while a spin lock provides implicit RCU protection. The pointer must be invalidated when the lock is released, which guards the required ordering between non-owning-reference invalidation and RCU demotion. Update the existing fault-protected load test state description. The post-unlock pointer no longer carries NON_OWN_REF, but remains readable because the load is rewritten to use BPF_PROBE_MEM. Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Link: https://lore.kernel.org/r/20260904084325.52250-7-memxor@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-09-04irqdomain: Delete irq_domain_add_linear()Jiri Slaby (SUSE)
7.3-rc1 is free of calls to irq_domain_add_linear(), so it can be finally deleted. According to Dongliang Mu, the related paragraph in the Chinese docs is now obsolete. So drop it completely. Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org> Signed-off-by: Thomas Gleixner <tglx@kernel.org> Reviewed-by: Dongliang Mu <dzm91@hust.edu.cn> Reviewed-by: Yanteng Si <si.yanteng@linux.dev> Link: https://patch.msgid.link/20260901070450.255507-1-jirislaby@kernel.org
2026-09-04futex: Provide rt_mutex_.*_schedule() equivalents for futex schedulingSebastian Andrzej Siewior
There is rt_mutex_{pre|post}_schedule() around rt_mutex_wait_proxy_lock() to ensure that sched_submit_work()/ sched_update_worker() is invoked before we schedule out and block on rt_mutex while waiting for it become available. The reason is that blocking on rt_mutex assigns a pi_waiter for the PI chain and sched_submit_work() will also assign a pi_waiter if it blocks on lock but a this point we already have a waiter assigned. We can't skip sched_submit_work() entirely because I/O relies on the fact that I/O queue is flushed while it blocks on a sleeping lock. Therefore sched_submit_work() is moved before we block on the lock. Sleeping lock in this context means mutex or rw_semaphore not spinlock_t on PREEMPT_RT. Because the mutex abstraction on PREEMPT_RT uses the same abstraction as the futex proxy lock, the futex code ended up using rt_mutex_{pre|post}_schedule(), too. Using it is/ was just to keep the task_struct::sched_rt_mutex assertion happy. Futex proxy lock is used only in the syscall context of a task. At this point it never got any I/O that needs to be flushed and it can't be a workqueue that needs to notify that it will be scheduled out. Therefore sched_submit_work() does nothing here. By mistake futex_wait_requeue_pi() -> rt_mutex_wait_proxy_lock() did not get the rt_mutex_{pre|post}_schedule() annotation. This was not noticed because in this callchain the lock is (usually) not contended and so rt_mutex_slowlock_block() does not schedule, triggering the assert. Adding rt_mutex_pre_schedule() here looks wrong (as noted by PeterZ) because at this point there is a pi_waiter recorded and invoking sched_submit_work() with a possible lock contention would be wrong. Add rt_mutex_futex_{pre|post}_schedule() which toggles the sched_rt_mutex assert and does not involve sched_submit_work(). Add asserts here to ensure that sched_submit_work() would do nothing. Use it only in futex proxy lock case which is rt_mutex_wait_proxy_lock(). Remove it from futex_lock_pi(). Fixes: d14f9e930b90 ("locking/rtmutex: Use rt_mutex specific scheduler helpers") Reported-by: Yao Kai <yaokai34@huawei.com> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@kernel.org> Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260901135453.3121948-2-bigeasy@linutronix.de Closes: https://lore.kernel.org/all/20260717084922.4153317-2-yaokai34@huawei.com
2026-09-02ftrace: Synchronize the initialization of ftrace_opsgraftedSteven Rostedt
There's some internal state that ftrace_ops needs to have set, but since it can be declared outside of the ftrace.c code, it calls ftrace_ops_init() on the ops in every global function. The issue is that if two tasks call it on the same ops at the same time it is possible to have the initialization of one corrupt the initialization of the other call. Create a ops_mutex to use to synchronize every initialization of the ftrace_ops. The mutex is taken within checking the ftrace_ops flag that states it was initializied but the flag is checked again after the mutex has been taken. Checking first outside the mutex allows it to shortcut having to take the mutex. But then the check needs to be done again after the mute is taken in case of races. Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260902095501.6b59af20@gandalf.local.home Fixes: f04f24fb7e48d ("ftrace, kprobes: Fix a deadlock on ftrace_regex_lock") Reported-by: sashiko-bot@kernel.org Close: https://lore.kernel.org/all/20260829025528.49A831F000E9@smtp.kernel.org/ Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-08-30preempt: Remove hardirq_disable_count()Boqun Feng
It turns out the previous usage of hardirq_disable_count() in __irq_exit_rcu() would cause softirq pending issues. Without that usage, hardirq_disable_count() doesn't need to exist, so remove it. Also move hardirq_disable_enter/exit() into the Rust specific interrupt_rc header. [ tglx: Move the helpers over ] Signed-off-by: Boqun Feng <boqun@kernel.org> Signed-off-by: Thomas Gleixner <tglx@kernel.org> Link: https://patch.msgid.link/20260827194835.38968-1-boqun@kernel.org
2026-08-30Merge tag 'locking-urgent-2026-08-30' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 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 ↵graftedLinus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace 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 Feng
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/
2026-08-24locking: Revert switching guards to _irq_{disable,enable}()Peter Zijlstra
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 'rcu.2026.08.18a' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rcu/linux 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 'i3c/for-7.3' of ↵graftedLinus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux Pull I3C updates from Alexandre Belloni: "A new driver this cycle, for the AMD AXI I3C controller. There are also new features such as IBI wakeup support, SETAASA device discovery and ACPI support for the the DAA methods, meaning we can now communicate with the SPD devices on DDR5 modules. New driver: - AMD AXI I3C master controller Subsystem: - I3C Common Command Code (CCC) handling improvements, especially around GET CCCs - SETAASA device discovery support - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as well as I2C devices on I3C bus - IBI-based wakeup support Drivers: - dw: SETAASA support - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C controller support, PIO queue management support for HCI v1.2 - renesas: improve suspend to RAM support, add runtime PM support" * tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits) i3c: dw: reduce do_daa time if there's no client i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2 i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode i3c: dw: rename "pclk" to "apb" to match dt-binding i3c: dw: make struct dw_i3c_cmd smaller i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding i3c: renesas: Don't register devices when ENTDAA times out i3c: master: dw-i3c-master: fix OD timing for first broadcast i3c: mipi-i3c-hci: Advertise IBI wakeup capability i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev() i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI i3c: master: Reject IBI requests from non-IBI-capable devices i3c: master: Add helper to query bus wakeup requirements i3c: master: Report wakeup events for IBIs i3c: master: Support IBI-based wakeup capability i3c: master: Fix potential UAF in i3c_device_match() i3c: master: Fix potential UAF in i3c_device_uevent() i3c: Make dev->desc locking assumptions explicit i3c: master: Fix use-after-free of master->this ...
2026-08-14Merge branches 'expcb.2026.07.24a', 'misc.2026.07.30a', ↵graftedPaul E. McKenney
'rcu-tasks.2026.07.30a', 'srcu.2026.08.11a' and 'torture.2026.08.14a' into HEAD Changes: 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.