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2025-06-23Merge 'v6.6.94'Francesco Dolcini
Merge 6.6.94 stable release
2025-06-19posix-cpu-timers: fix race between handle_posix_cpu_timers() and ↵Oleg Nesterov
posix_cpu_timer_del() commit f90fff1e152dedf52b932240ebbd670d83330eca upstream. If an exiting non-autoreaping task has already passed exit_notify() and calls handle_posix_cpu_timers() from IRQ, it can be reaped by its parent or debugger right after unlock_task_sighand(). If a concurrent posix_cpu_timer_del() runs at that moment, it won't be able to detect timer->it.cpu.firing != 0: cpu_timer_task_rcu() and/or lock_task_sighand() will fail. Add the tsk->exit_state check into run_posix_cpu_timers() to fix this. This fix is not needed if CONFIG_POSIX_CPU_TIMERS_TASK_WORK=y, because exit_task_work() is called before exit_notify(). But the check still makes sense, task_work_add(&tsk->posix_cputimers_work.work) will fail anyway in this case. Cc: stable@vger.kernel.org Reported-by: Benoît Sevens <bsevens@google.com> Fixes: 0bdd2ed4138e ("sched: run_posix_cpu_timers: Don't check ->exit_state, use lock_task_sighand()") Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-06-19perf: Ensure bpf_perf_link path is properly serializedPeter Zijlstra
[ Upstream commit 7ed9138a72829d2035ecbd8dbd35b1bc3c137c40 ] Ravi reported that the bpf_perf_link_attach() usage of perf_event_set_bpf_prog() is not serialized by ctx->mutex, unlike the PERF_EVENT_IOC_SET_BPF case. Reported-by: Ravi Bangoria <ravi.bangoria@amd.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Ravi Bangoria <ravi.bangoria@amd.com> Link: https://lkml.kernel.org/r/20250307193305.486326750@infradead.org Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-19bpf: Avoid __bpf_prog_ret0_warn when jit failsKaFai Wan
[ Upstream commit 86bc9c742426a16b52a10ef61f5b721aecca2344 ] syzkaller reported an issue: WARNING: CPU: 3 PID: 217 at kernel/bpf/core.c:2357 __bpf_prog_ret0_warn+0xa/0x20 kernel/bpf/core.c:2357 Modules linked in: CPU: 3 UID: 0 PID: 217 Comm: kworker/u32:6 Not tainted 6.15.0-rc4-syzkaller-00040-g8bac8898fe39 RIP: 0010:__bpf_prog_ret0_warn+0xa/0x20 kernel/bpf/core.c:2357 Call Trace: <TASK> bpf_dispatcher_nop_func include/linux/bpf.h:1316 [inline] __bpf_prog_run include/linux/filter.h:718 [inline] bpf_prog_run include/linux/filter.h:725 [inline] cls_bpf_classify+0x74a/0x1110 net/sched/cls_bpf.c:105 ... When creating bpf program, 'fp->jit_requested' depends on bpf_jit_enable. This issue is triggered because of CONFIG_BPF_JIT_ALWAYS_ON is not set and bpf_jit_enable is set to 1, causing the arch to attempt JIT the prog, but jit failed due to FAULT_INJECTION. As a result, incorrectly treats the program as valid, when the program runs it calls `__bpf_prog_ret0_warn` and triggers the WARN_ON_ONCE(1). Reported-by: syzbot+0903f6d7f285e41cdf10@syzkaller.appspotmail.com Closes: https://lore.kernel.org/bpf/6816e34e.a70a0220.254cdc.002c.GAE@google.com Fixes: fa9dd599b4da ("bpf: get rid of pure_initcall dependency to enable jits") Signed-off-by: KaFai Wan <mannkafai@gmail.com> Link: https://lore.kernel.org/r/20250526133358.2594176-1-mannkafai@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-19bpf: Fix WARN() in get_bpf_raw_tp_regsTao Chen
[ Upstream commit 3880cdbed1c4607e378f58fa924c5d6df900d1d3 ] syzkaller reported an issue: WARNING: CPU: 3 PID: 5971 at kernel/trace/bpf_trace.c:1861 get_bpf_raw_tp_regs+0xa4/0x100 kernel/trace/bpf_trace.c:1861 Modules linked in: CPU: 3 UID: 0 PID: 5971 Comm: syz-executor205 Not tainted 6.15.0-rc5-syzkaller-00038-g707df3375124 #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 RIP: 0010:get_bpf_raw_tp_regs+0xa4/0x100 kernel/trace/bpf_trace.c:1861 RSP: 0018:ffffc90003636fa8 EFLAGS: 00010293 RAX: 0000000000000000 RBX: 0000000000000003 RCX: ffffffff81c6bc4c RDX: ffff888032efc880 RSI: ffffffff81c6bc83 RDI: 0000000000000005 RBP: ffff88806a730860 R08: 0000000000000005 R09: 0000000000000003 R10: 0000000000000004 R11: 0000000000000000 R12: 0000000000000004 R13: 0000000000000001 R14: ffffc90003637008 R15: 0000000000000900 FS: 0000000000000000(0000) GS:ffff8880d6cdf000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7baee09130 CR3: 0000000029f5a000 CR4: 0000000000352ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> ____bpf_get_stack_raw_tp kernel/trace/bpf_trace.c:1934 [inline] bpf_get_stack_raw_tp+0x24/0x160 kernel/trace/bpf_trace.c:1931 bpf_prog_ec3b2eefa702d8d3+0x43/0x47 bpf_dispatcher_nop_func include/linux/bpf.h:1316 [inline] __bpf_prog_run include/linux/filter.h:718 [inline] bpf_prog_run include/linux/filter.h:725 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2363 [inline] bpf_trace_run3+0x23f/0x5a0 kernel/trace/bpf_trace.c:2405 __bpf_trace_mmap_lock_acquire_returned+0xfc/0x140 include/trace/events/mmap_lock.h:47 __traceiter_mmap_lock_acquire_returned+0x79/0xc0 include/trace/events/mmap_lock.h:47 __do_trace_mmap_lock_acquire_returned include/trace/events/mmap_lock.h:47 [inline] trace_mmap_lock_acquire_returned include/trace/events/mmap_lock.h:47 [inline] __mmap_lock_do_trace_acquire_returned+0x138/0x1f0 mm/mmap_lock.c:35 __mmap_lock_trace_acquire_returned include/linux/mmap_lock.h:36 [inline] mmap_read_trylock include/linux/mmap_lock.h:204 [inline] stack_map_get_build_id_offset+0x535/0x6f0 kernel/bpf/stackmap.c:157 __bpf_get_stack+0x307/0xa10 kernel/bpf/stackmap.c:483 ____bpf_get_stack kernel/bpf/stackmap.c:499 [inline] bpf_get_stack+0x32/0x40 kernel/bpf/stackmap.c:496 ____bpf_get_stack_raw_tp kernel/trace/bpf_trace.c:1941 [inline] bpf_get_stack_raw_tp+0x124/0x160 kernel/trace/bpf_trace.c:1931 bpf_prog_ec3b2eefa702d8d3+0x43/0x47 Tracepoint like trace_mmap_lock_acquire_returned may cause nested call as the corner case show above, which will be resolved with more general method in the future. As a result, WARN_ON_ONCE will be triggered. As Alexei suggested, remove the WARN_ON_ONCE first. Fixes: 9594dc3c7e71 ("bpf: fix nested bpf tracepoints with per-cpu data") Reported-by: syzbot+45b0c89a0fc7ae8dbadc@syzkaller.appspotmail.com Suggested-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Tao Chen <chen.dylane@linux.dev> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20250513042747.757042-1-chen.dylane@linux.dev Closes: https://lore.kernel.org/bpf/8bc2554d-1052-4922-8832-e0078a033e1d@gmail.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-19tracing: Fix error handling in event_trigger_parse()Miaoqian Lin
[ Upstream commit c5dd28e7fb4f63475b50df4f58311df92939d011 ] According to trigger_data_alloc() doc, trigger_data_free() should be used to free an event_trigger_data object. This fixes a mismatch introduced when kzalloc was replaced with trigger_data_alloc without updating the corresponding deallocation calls. Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Tom Zanussi <zanussi@kernel.org> Link: https://lore.kernel.org/20250507145455.944453325@goodmis.org Link: https://lore.kernel.org/20250318112737.4174-1-linmq006@gmail.com Fixes: e1f187d09e11 ("tracing: Have existing event_command.parse() implementations use helpers") Signed-off-by: Miaoqian Lin <linmq006@gmail.com> [ SDR: Changed event_trigger_alloc/free() to trigger_data_alloc/free() ] Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-19tracing: Rename event_trigger_alloc() to trigger_data_alloc()Steven Rostedt
[ Upstream commit f2947c4b7d0f235621c5daf78aecfbd6e22c05e5 ] The function event_trigger_alloc() creates an event_trigger_data descriptor and states that it needs to be freed via event_trigger_free(). This is incorrect, it needs to be freed by trigger_data_free() as event_trigger_free() adds ref counting. Rename event_trigger_alloc() to trigger_data_alloc() and state that it needs to be freed via trigger_data_free(). This naming convention was introducing bugs. Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Tom Zanussi <zanussi@kernel.org> Link: https://lore.kernel.org/20250507145455.776436410@goodmis.org Fixes: 86599dbe2c527 ("tracing: Add helper functions to simplify event_command.parse() callback handling") Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-19tracing: Move histogram trigger variables from stack to per CPU structureSteven Rostedt
[ Upstream commit 7ab0fc61ce73040f89b12d76a8279995ec283541 ] The histogram trigger has three somewhat large arrays on the kernel stack: unsigned long entries[HIST_STACKTRACE_DEPTH]; u64 var_ref_vals[TRACING_MAP_VARS_MAX]; char compound_key[HIST_KEY_SIZE_MAX]; Checking the function event_hist_trigger() stack frame size, it currently uses 816 bytes for its stack frame due to these variables! Instead, allocate a per CPU structure that holds these arrays for each context level (normal, softirq, irq and NMI). That is, each CPU will have 4 of these structures. This will be allocated when the first histogram trigger is enabled and freed when the last is disabled. When the histogram callback triggers, it will request this structure. The request will disable preemption, get the per CPU structure at the index of the per CPU variable, and increment that variable. The callback will use the arrays in this structure to perform its work and then release the structure. That in turn will simply decrement the per CPU index and enable preemption. Moving the variables from the kernel stack to the per CPU structure brings the stack frame of event_hist_trigger() down to just 112 bytes. Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Tom Zanussi <zanussi@kernel.org> Link: https://lore.kernel.org/20250407123851.74ea8d58@gandalf.local.home Fixes: 067fe038e70f6 ("tracing: Add variable reference handling to hist triggers") Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-19bpf: Allow XDP dev-bound programs to perform XDP_REDIRECT into mapsLorenzo Bianconi
[ Upstream commit 714070c4cb7a10ff57450a618a936775f3036245 ] In the current implementation if the program is dev-bound to a specific device, it will not be possible to perform XDP_REDIRECT into a DEVMAP or CPUMAP even if the program is running in the driver NAPI context and it is not attached to any map entry. This seems in contrast with the explanation available in bpf_prog_map_compatible routine. Fix the issue introducing __bpf_prog_map_compatible utility routine in order to avoid bpf_prog_is_dev_bound() check running bpf_check_tail_call() at program load time (bpf_prog_select_runtime()). Continue forbidding to attach a dev-bound program to XDP maps (BPF_MAP_TYPE_PROG_ARRAY, BPF_MAP_TYPE_DEVMAP and BPF_MAP_TYPE_CPUMAP). Fixes: 3d76a4d3d4e59 ("bpf: XDP metadata RX kfuncs") Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Acked-by: Stanislav Fomichev <sdf@fomichev.me> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-19PM: sleep: Print PM debug messages during hibernationRafael J. Wysocki
[ Upstream commit 1b17d4525bca3916644c41e01522df8fa0f8b90b ] Commit cdb8c100d8a4 ("include/linux/suspend.h: Only show pm_pr_dbg messages at suspend/resume") caused PM debug messages to only be printed during system-wide suspend and resume in progress, but it forgot about hibernation. Address this by adding a check for hibernation in progress to pm_debug_messages_should_print(). Fixes: cdb8c100d8a4 ("include/linux/suspend.h: Only show pm_pr_dbg messages at suspend/resume") Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Mario Limonciello <mario.limonciello@amd.com> Link: https://patch.msgid.link/4998903.GXAFRqVoOG@rjwysocki.net Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-19PM: wakeup: Delete space in the end of string shown by pm_show_wakelocks()Zijun Hu
[ Upstream commit f0050a3e214aa941b78ad4caf122a735a24d81a6 ] pm_show_wakelocks() is called to generate a string when showing attributes /sys/power/wake_(lock|unlock), but the string ends with an unwanted space that was added back by mistake by commit c9d967b2ce40 ("PM: wakeup: simplify the output logic of pm_show_wakelocks()"). Remove the unwanted space. Fixes: c9d967b2ce40 ("PM: wakeup: simplify the output logic of pm_show_wakelocks()") Signed-off-by: Zijun Hu <quic_zijuhu@quicinc.com> Link: https://patch.msgid.link/20250505-fix_power-v1-1-0f7f2c2f338c@quicinc.com [ rjw: Changelog edits ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-19rcu/cpu_stall_cputime: fix the hardirq count for x86 architectureYongliang Gao
[ Upstream commit da6b85598af30e9fec34d82882d7e1e39f3da769 ] When counting the number of hardirqs in the x86 architecture, it is essential to add arch_irq_stat_cpu to ensure accuracy. For example, a CPU loop within the rcu_read_lock function. Before: [ 70.910184] rcu: INFO: rcu_preempt self-detected stall on CPU [ 70.910436] rcu: 3-....: (4999 ticks this GP) idle=*** [ 70.910711] rcu: hardirqs softirqs csw/system [ 70.910870] rcu: number: 0 657 0 [ 70.911024] rcu: cputime: 0 0 2498 ==> 2498(ms) [ 70.911278] rcu: (t=5001 jiffies g=3677 q=29 ncpus=8) After: [ 68.046132] rcu: INFO: rcu_preempt self-detected stall on CPU [ 68.046354] rcu: 2-....: (4999 ticks this GP) idle=*** [ 68.046628] rcu: hardirqs softirqs csw/system [ 68.046793] rcu: number: 2498 663 0 [ 68.046951] rcu: cputime: 0 0 2496 ==> 2496(ms) [ 68.047244] rcu: (t=5000 jiffies g=3825 q=4 ncpus=8) Fixes: be42f00b73a0 ("rcu: Add RCU stall diagnosis information") Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202501090842.SfI6QPGS-lkp@intel.com/ Signed-off-by: Yongliang Gao <leonylgao@tencent.com> Reviewed-by: Neeraj Upadhyay <Neeraj.Upadhyay@amd.com> Link: https://lore.kernel.org/r/20250216084109.3109837-1-leonylgao@gmail.com Signed-off-by: Boqun Feng <boqun.feng@gmail.com> Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-19perf/core: Fix broken throttling when max_samples_per_tick=1Qing Wang
[ Upstream commit f51972e6f8b9a737b2b3eb588069acb538fa72de ] According to the throttling mechanism, the pmu interrupts number can not exceed the max_samples_per_tick in one tick. But this mechanism is ineffective when max_samples_per_tick=1, because the throttling check is skipped during the first interrupt and only performed when the second interrupt arrives. Perhaps this bug may cause little influence in one tick, but if in a larger time scale, the problem can not be underestimated. When max_samples_per_tick = 1: Allowed-interrupts-per-second max-samples-per-second default-HZ ARCH 200 100 100 X86 500 250 250 ARM64 ... Obviously, the pmu interrupt number far exceed the user's expect. Fixes: e050e3f0a71b ("perf: Fix broken interrupt rate throttling") Signed-off-by: Qing Wang <wangqing7171@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20250405141635.243786-3-wangqing7171@gmail.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-19tracing: Fix compilation warning on arm32Pan Taixi
commit 2fbdb6d8e03b70668c0876e635506540ae92ab05 upstream. On arm32, size_t is defined to be unsigned int, while PAGE_SIZE is unsigned long. This hence triggers a compilation warning as min() asserts the type of two operands to be equal. Casting PAGE_SIZE to size_t solves this issue and works on other target architectures as well. Compilation warning details: kernel/trace/trace.c: In function 'tracing_splice_read_pipe': ./include/linux/minmax.h:20:28: warning: comparison of distinct pointer types lacks a cast (!!(sizeof((typeof(x) *)1 == (typeof(y) *)1))) ^ ./include/linux/minmax.h:26:4: note: in expansion of macro '__typecheck' (__typecheck(x, y) && __no_side_effects(x, y)) ^~~~~~~~~~~ ... kernel/trace/trace.c:6771:8: note: in expansion of macro 'min' min((size_t)trace_seq_used(&iter->seq), ^~~ Cc: stable@vger.kernel.org Link: https://lore.kernel.org/20250526013731.1198030-1-pantaixi@huaweicloud.com Fixes: f5178c41bb43 ("tracing: Fix oob write in trace_seq_to_buffer()") Reviewed-by: Jeongjun Park <aha310510@gmail.com> Signed-off-by: Pan Taixi <pantaixi@huaweicloud.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-06-17Merge tag 'v6.6.93'Francesco Dolcini
Merge 6.6.93 stable release
2025-06-04hrtimers: Force migrate away hrtimers queued after CPUHP_AP_HRTIMERS_DYINGFrederic Weisbecker
commit 53dac345395c0d2493cbc2f4c85fe38aef5b63f5 upstream. hrtimers are migrated away from the dying CPU to any online target at the CPUHP_AP_HRTIMERS_DYING stage in order not to delay bandwidth timers handling tasks involved in the CPU hotplug forward progress. However wakeups can still be performed by the outgoing CPU after CPUHP_AP_HRTIMERS_DYING. Those can result again in bandwidth timers being armed. Depending on several considerations (crystal ball power management based election, earliest timer already enqueued, timer migration enabled or not), the target may eventually be the current CPU even if offline. If that happens, the timer is eventually ignored. The most notable example is RCU which had to deal with each and every of those wake-ups by deferring them to an online CPU, along with related workarounds: _ e787644caf76 (rcu: Defer RCU kthreads wakeup when CPU is dying) _ 9139f93209d1 (rcu/nocb: Fix RT throttling hrtimer armed from offline CPU) _ f7345ccc62a4 (rcu/nocb: Fix rcuog wake-up from offline softirq) The problem isn't confined to RCU though as the stop machine kthread (which runs CPUHP_AP_HRTIMERS_DYING) reports its completion at the end of its work through cpu_stop_signal_done() and performs a wake up that eventually arms the deadline server timer: WARNING: CPU: 94 PID: 588 at kernel/time/hrtimer.c:1086 hrtimer_start_range_ns+0x289/0x2d0 CPU: 94 UID: 0 PID: 588 Comm: migration/94 Not tainted Stopper: multi_cpu_stop+0x0/0x120 <- stop_machine_cpuslocked+0x66/0xc0 RIP: 0010:hrtimer_start_range_ns+0x289/0x2d0 Call Trace: <TASK> start_dl_timer enqueue_dl_entity dl_server_start enqueue_task_fair enqueue_task ttwu_do_activate try_to_wake_up complete cpu_stopper_thread Instead of providing yet another bandaid to work around the situation, fix it in the hrtimers infrastructure instead: always migrate away a timer to an online target whenever it is enqueued from an offline CPU. This will also allow to revert all the above RCU disgraceful hacks. Fixes: 5c0930ccaad5 ("hrtimers: Push pending hrtimers away from outgoing CPU earlier") Reported-by: Vlad Poenaru <vlad.wing@gmail.com> Reported-by: Usama Arif <usamaarif642@gmail.com> Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Tested-by: Paul E. McKenney <paulmck@kernel.org> Link: https://lore.kernel.org/all/20250117232433.24027-1-frederic@kernel.org Closes: 20241213203739.1519801-1-usamaarif642@gmail.com Signed-off-by: Zhaoyang Li <lizy04@hust.edu.cn> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-06-04padata: do not leak refcount in reorder_workDominik Grzegorzek
commit d6ebcde6d4ecf34f8495fb30516645db3aea8993 upstream. A recent patch that addressed a UAF introduced a reference count leak: the parallel_data refcount is incremented unconditionally, regardless of the return value of queue_work(). If the work item is already queued, the incremented refcount is never decremented. Fix this by checking the return value of queue_work() and decrementing the refcount when necessary. Resolves: Unreferenced object 0xffff9d9f421e3d80 (size 192): comm "cryptomgr_probe", pid 157, jiffies 4294694003 hex dump (first 32 bytes): 80 8b cf 41 9f 9d ff ff b8 97 e0 89 ff ff ff ff ...A............ d0 97 e0 89 ff ff ff ff 19 00 00 00 1f 88 23 00 ..............#. backtrace (crc 838fb36): __kmalloc_cache_noprof+0x284/0x320 padata_alloc_pd+0x20/0x1e0 padata_alloc_shell+0x3b/0xa0 0xffffffffc040a54d cryptomgr_probe+0x43/0xc0 kthread+0xf6/0x1f0 ret_from_fork+0x2f/0x50 ret_from_fork_asm+0x1a/0x30 Fixes: dd7d37ccf6b1 ("padata: avoid UAF for reorder_work") Cc: <stable@vger.kernel.org> Signed-off-by: Dominik Grzegorzek <dominik.grzegorzek@oracle.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-06-04kernel/fork: only call untrack_pfn_clear() on VMAs duplicated for fork()David Hildenbrand
[ Upstream commit e9f180d7cfde23b9f8eebd60272465176373ab2c ] Not intuitive, but vm_area_dup() located in kernel/fork.c is not only used for duplicating VMAs during fork(), but also for duplicating VMAs when splitting VMAs or when mremap()'ing them. VM_PFNMAP mappings can at least get ordinarily mremap()'ed (no change in size) and apparently also shrunk during mremap(), which implies duplicating the VMA in __split_vma() first. In case of ordinary mremap() (no change in size), we first duplicate the VMA in copy_vma_and_data()->copy_vma() to then call untrack_pfn_clear() on the old VMA: we effectively move the VM_PAT reservation. So the untrack_pfn_clear() call on the new VMA duplicating is wrong in that context. Splitting of VMAs seems problematic, because we don't duplicate/adjust the reservation when splitting the VMA. Instead, in memtype_erase() -- called during zapping/munmap -- we shrink a reservation in case only the end address matches: Assume we split a VMA into A and B, both would share a reservation until B is unmapped. So when unmapping B, the reservation would be updated to cover only A. When unmapping A, we would properly remove the now-shrunk reservation. That scenario describes the mremap() shrinking (old_size > new_size), where we split + unmap B, and the untrack_pfn_clear() on the new VMA when is wrong. What if we manage to split a VM_PFNMAP VMA into A and B and unmap A first? It would be broken because we would never free the reservation. Likely, there are ways to trigger such a VMA split outside of mremap(). Affecting other VMA duplication was not intended, vm_area_dup() being used outside of kernel/fork.c was an oversight. So let's fix that for; how to handle VMA splits better should be investigated separately. With a simple reproducer that uses mprotect() to split such a VMA I can trigger x86/PAT: pat_mremap:26448 freeing invalid memtype [mem 0x00000000-0x00000fff] Link: https://lkml.kernel.org/r/20250422144942.2871395-1-david@redhat.com Fixes: dc84bc2aba85 ("x86/mm/pat: Fix VM_PAT handling when fork() fails in copy_page_range()") Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Rik van Riel <riel@surriel.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-04perf: Avoid the read if the count is already updatedPeter Zijlstra (Intel)
[ Upstream commit 8ce939a0fa194939cc1f92dbd8bc1a7806e7d40a ] The event may have been updated in the PMU-specific implementation, e.g., Intel PEBS counters snapshotting. The common code should not read and overwrite the value. The PERF_SAMPLE_READ in the data->sample_type can be used to detect whether the PMU-specific value is available. If yes, avoid the pmu->read() in the common code. Add a new flag, skip_read, to track the case. Factor out a perf_pmu_read() to clean up the code. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20250121152303.3128733-3-kan.liang@linux.intel.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-04rcu: handle unstable rdp in rcu_read_unlock_strict()Ankur Arora
[ Upstream commit fcf0e25ad4c8d14d2faab4d9a17040f31efce205 ] rcu_read_unlock_strict() can be called with preemption enabled which can make for an unstable rdp and a racy norm value. Fix this by dropping the preempt-count in __rcu_read_unlock() after the call to rcu_read_unlock_strict(), adjusting the preempt-count check appropriately. Suggested-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Ankur Arora <ankur.a.arora@oracle.com> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Boqun Feng <boqun.feng@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-04rcu: handle quiescent states for PREEMPT_RCU=n, PREEMPT_COUNT=yAnkur Arora
[ Upstream commit 83b28cfe796464ebbde1cf7916c126da6d572685 ] With PREEMPT_RCU=n, cond_resched() provides urgently needed quiescent states for read-side critical sections via rcu_all_qs(). One reason why this was needed: lacking preempt-count, the tick handler has no way of knowing whether it is executing in a read-side critical section or not. With (PREEMPT_LAZY=y, PREEMPT_DYNAMIC=n), we get (PREEMPT_COUNT=y, PREEMPT_RCU=n). In this configuration cond_resched() is a stub and does not provide quiescent states via rcu_all_qs(). (PREEMPT_RCU=y provides this information via rcu_read_unlock() and its nesting counter.) So, use the availability of preempt_count() to report quiescent states in rcu_flavor_sched_clock_irq(). Suggested-by: Paul E. McKenney <paulmck@kernel.org> Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Ankur Arora <ankur.a.arora@oracle.com> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Boqun Feng <boqun.feng@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-04sched: Reduce the default slice to avoid tasks getting an extra tickzihan zhou
[ Upstream commit 2ae891b826958b60919ea21c727f77bcd6ffcc2c ] The old default value for slice is 0.75 msec * (1 + ilog(ncpus)) which means that we have a default slice of: 0.75 for 1 cpu 1.50 up to 3 cpus 2.25 up to 7 cpus 3.00 for 8 cpus and above. For HZ=250 and HZ=100, because of the tick accuracy, the runtime of tasks is far higher than their slice. For HZ=1000 with 8 cpus or more, the accuracy of tick is already satisfactory, but there is still an issue that tasks will get an extra tick because the tick often arrives a little faster than expected. In this case, the task can only wait until the next tick to consider that it has reached its deadline, and will run 1ms longer. vruntime + sysctl_sched_base_slice = deadline |-----------|-----------|-----------|-----------| 1ms 1ms 1ms 1ms ^ ^ ^ ^ tick1 tick2 tick3 tick4(nearly 4ms) There are two reasons for tick error: clockevent precision and the CONFIG_IRQ_TIME_ACCOUNTING/CONFIG_PARAVIRT_TIME_ACCOUNTING. with CONFIG_IRQ_TIME_ACCOUNTING every tick will be less than 1ms, but even without it, because of clockevent precision, tick still often less than 1ms. In order to make scheduling more precise, we changed 0.75 to 0.70, Using 0.70 instead of 0.75 should not change much for other configs and would fix this issue: 0.70 for 1 cpu 1.40 up to 3 cpus 2.10 up to 7 cpus 2.8 for 8 cpus and above. This does not guarantee that tasks can run the slice time accurately every time, but occasionally running an extra tick has little impact. Signed-off-by: zihan zhou <15645113830zzh@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org> Link: https://lkml.kernel.org/r/20250208075322.13139-1-15645113830zzh@gmail.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-04bpf: don't do clean_live_states when state->loop_entry->branches > 0Eduard Zingerman
[ Upstream commit 9e63fdb0cbdf3268c86638a8274f4d5549a82820 ] verifier.c:is_state_visited() uses RANGE_WITHIN states comparison rules for cached states that have loop_entry with non-zero branches count (meaning that loop_entry's verification is not yet done). The RANGE_WITHIN rules in regsafe()/stacksafe() require register and stack objects types to be identical in current and old states. verifier.c:clean_live_states() replaces registers and stack spills with NOT_INIT/STACK_INVALID marks, if these registers/stack spills are not read in any child state. This means that clean_live_states() works against loop convergence logic under some conditions. See selftest in the next patch for a specific example. Mitigate this by prohibiting clean_verifier_state() when state->loop_entry->branches > 0. This undoes negative verification performance impact of the copy_verifier_state() fix from the previous patch. Below is comparison between master and current patch. selftests: File Program Insns (A) Insns (B) Insns (DIFF) States (A) States (B) States (DIFF) ---------------------------------- ---------------------------- --------- --------- --------------- ---------- ---------- -------------- arena_htab.bpf.o arena_htab_llvm 717 423 -294 (-41.00%) 57 37 -20 (-35.09%) arena_htab_asm.bpf.o arena_htab_asm 597 445 -152 (-25.46%) 47 37 -10 (-21.28%) arena_list.bpf.o arena_list_add 1493 1822 +329 (+22.04%) 30 37 +7 (+23.33%) arena_list.bpf.o arena_list_del 309 261 -48 (-15.53%) 23 15 -8 (-34.78%) iters.bpf.o checkpoint_states_deletion 18125 22154 +4029 (+22.23%) 818 918 +100 (+12.22%) iters.bpf.o iter_nested_deeply_iters 593 367 -226 (-38.11%) 67 43 -24 (-35.82%) iters.bpf.o iter_nested_iters 813 772 -41 (-5.04%) 79 72 -7 (-8.86%) iters.bpf.o iter_subprog_check_stacksafe 155 135 -20 (-12.90%) 15 14 -1 (-6.67%) iters.bpf.o iter_subprog_iters 1094 808 -286 (-26.14%) 88 68 -20 (-22.73%) iters.bpf.o loop_state_deps2 479 356 -123 (-25.68%) 46 35 -11 (-23.91%) iters.bpf.o triple_continue 35 31 -4 (-11.43%) 3 3 +0 (+0.00%) kmem_cache_iter.bpf.o open_coded_iter 63 59 -4 (-6.35%) 7 6 -1 (-14.29%) mptcp_subflow.bpf.o _getsockopt_subflow 501 446 -55 (-10.98%) 25 23 -2 (-8.00%) pyperf600_iter.bpf.o on_event 12339 6379 -5960 (-48.30%) 441 286 -155 (-35.15%) verifier_bits_iter.bpf.o max_words 92 84 -8 (-8.70%) 8 7 -1 (-12.50%) verifier_iterating_callbacks.bpf.o cond_break2 113 192 +79 (+69.91%) 12 21 +9 (+75.00%) sched_ext: File Program Insns (A) Insns (B) Insns (DIFF) States (A) States (B) States (DIFF) ----------------- ---------------------- --------- --------- ----------------- ---------- ---------- ---------------- bpf.bpf.o layered_dispatch 11485 9039 -2446 (-21.30%) 848 662 -186 (-21.93%) bpf.bpf.o layered_dump 7422 5022 -2400 (-32.34%) 681 298 -383 (-56.24%) bpf.bpf.o layered_enqueue 16854 13753 -3101 (-18.40%) 1611 1308 -303 (-18.81%) bpf.bpf.o layered_init 1000001 5549 -994452 (-99.45%) 84672 523 -84149 (-99.38%) bpf.bpf.o layered_runnable 3149 1899 -1250 (-39.70%) 288 151 -137 (-47.57%) bpf.bpf.o p2dq_init 2343 1936 -407 (-17.37%) 201 170 -31 (-15.42%) bpf.bpf.o refresh_layer_cpumasks 16487 1285 -15202 (-92.21%) 1770 120 -1650 (-93.22%) bpf.bpf.o rusty_select_cpu 1937 1386 -551 (-28.45%) 177 125 -52 (-29.38%) scx_central.bpf.o central_dispatch 636 600 -36 (-5.66%) 63 59 -4 (-6.35%) scx_central.bpf.o central_init 913 632 -281 (-30.78%) 48 39 -9 (-18.75%) scx_nest.bpf.o nest_init 636 601 -35 (-5.50%) 60 58 -2 (-3.33%) scx_pair.bpf.o pair_dispatch 1000001 1914 -998087 (-99.81%) 58169 142 -58027 (-99.76%) scx_qmap.bpf.o qmap_dispatch 2393 2187 -206 (-8.61%) 196 174 -22 (-11.22%) scx_qmap.bpf.o qmap_init 16367 22777 +6410 (+39.16%) 603 768 +165 (+27.36%) 'layered_init' and 'pair_dispatch' hit 1M on master, but are verified ok with this patch. Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20250215110411.3236773-4-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-04perf/hw_breakpoint: Return EOPNOTSUPP for unsupported breakpoint typeSaket Kumar Bhaskar
[ Upstream commit 061c991697062f3bf87b72ed553d1d33a0e370dd ] Currently, __reserve_bp_slot() returns -ENOSPC for unsupported breakpoint types on the architecture. For example, powerpc does not support hardware instruction breakpoints. This causes the perf_skip BPF selftest to fail, as neither ENOENT nor EOPNOTSUPP is returned by perf_event_open for unsupported breakpoint types. As a result, the test that should be skipped for this arch is not correctly identified. To resolve this, hw_breakpoint_event_init() should exit early by checking for unsupported breakpoint types using hw_breakpoint_slots_cached() and return the appropriate error (-EOPNOTSUPP). Signed-off-by: Saket Kumar Bhaskar <skb99@linux.ibm.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Marco Elver <elver@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Ian Rogers <irogers@google.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Link: https://lore.kernel.org/r/20250303092451.1862862-1-skb99@linux.ibm.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-04printk: Check CON_SUSPEND when unblanking a consoleMarcos Paulo de Souza
[ Upstream commit 72c96a2dacc0fb056d13a5f02b0845c4c910fe54 ] The commit 9e70a5e109a4 ("printk: Add per-console suspended state") introduced the CON_SUSPENDED flag for consoles. The suspended consoles will stop receiving messages, so don't unblank suspended consoles because it won't be showing anything either way. Signed-off-by: Marcos Paulo de Souza <mpdesouza@suse.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Reviewed-by: John Ogness <john.ogness@linutronix.de> Link: https://lore.kernel.org/r/20250226-printk-renaming-v1-5-0b878577f2e6@suse.com Signed-off-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-04timer_list: Don't use %pK through printk()Thomas Weißschuh
[ Upstream commit a52067c24ccf6ee4c85acffa0f155e9714f9adce ] This reverts commit f590308536db ("timer debug: Hide kernel addresses via %pK in /proc/timer_list") The timer list helper SEQ_printf() uses either the real seq_printf() for procfs output or vprintk() to print to the kernel log, when invoked from SysRq-q. It uses %pK for printing pointers. In the past %pK was prefered over %p as it would not leak raw pointer values into the kernel log. Since commit ad67b74d2469 ("printk: hash addresses printed with %p") the regular %p has been improved to avoid this issue. Furthermore, restricted pointers ("%pK") were never meant to be used through printk(). They can still unintentionally leak raw pointers or acquire sleeping looks in atomic contexts. Switch to the regular pointer formatting which is safer, easier to reason about and sufficient here. Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/lkml/20250113171731-dc10e3c1-da64-4af0-b767-7c7070468023@linutronix.de/ Link: https://lore.kernel.org/all/20250311-restricted-pointers-timer-v1-1-6626b91e54ab@linutronix.de Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-04posix-timers: Add cond_resched() to posix_timer_add() search loopEric Dumazet
[ Upstream commit 5f2909c6cd13564a07ae692a95457f52295c4f22 ] With a large number of POSIX timers the search for a valid ID might cause a soft lockup on PREEMPT_NONE/VOLUNTARY kernels. Add cond_resched() to the loop to prevent that. [ tglx: Split out from Eric's series ] Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/all/20250214135911.2037402-2-edumazet@google.com Link: https://lore.kernel.org/all/20250308155623.635612865@linutronix.de Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-04bpf: Allow pre-ordering for bpf cgroup progsYonghong Song
[ Upstream commit 4b82b181a26cff8bf7adc3a85a88d121d92edeaf ] Currently for bpf progs in a cgroup hierarchy, the effective prog array is computed from bottom cgroup to upper cgroups (post-ordering). For example, the following cgroup hierarchy root cgroup: p1, p2 subcgroup: p3, p4 have BPF_F_ALLOW_MULTI for both cgroup levels. The effective cgroup array ordering looks like p3 p4 p1 p2 and at run time, progs will execute based on that order. But in some cases, it is desirable to have root prog executes earlier than children progs (pre-ordering). For example, - prog p1 intends to collect original pkt dest addresses. - prog p3 will modify original pkt dest addresses to a proxy address for security reason. The end result is that prog p1 gets proxy address which is not what it wants. Putting p1 to every child cgroup is not desirable either as it will duplicate itself in many child cgroups. And this is exactly a use case we are encountering in Meta. To fix this issue, let us introduce a flag BPF_F_PREORDER. If the flag is specified at attachment time, the prog has higher priority and the ordering with that flag will be from top to bottom (pre-ordering). For example, in the above example, root cgroup: p1, p2 subcgroup: p3, p4 Let us say p2 and p4 are marked with BPF_F_PREORDER. The final effective array ordering will be p2 p4 p3 p1 Suggested-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/r/20250224230116.283071-1-yonghong.song@linux.dev Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-04bpf: Return prog btf_id without capable checkMykyta Yatsenko
[ Upstream commit 07651ccda9ff10a8ca427670cdd06ce2c8e4269c ] Return prog's btf_id from bpf_prog_get_info_by_fd regardless of capable check. This patch enables scenario, when freplace program, running from user namespace, requires to query target prog's btf. Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/bpf/20250317174039.161275-3-mykyta.yatsenko5@gmail.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-04lockdep: Fix wait context check on softirq for PREEMPT_RTRyo Takakura
[ Upstream commit 61c39d8c83e2077f33e0a2c8980a76a7f323f0ce ] Since: 0c1d7a2c2d32 ("lockdep: Remove softirq accounting on PREEMPT_RT.") the wait context test for mutex usage within "in softirq context" fails as it references @softirq_context: | wait context tests | -------------------------------------------------------------------------- | rcu | raw | spin |mutex | -------------------------------------------------------------------------- in hardirq context: ok | ok | ok | ok | in hardirq context (not threaded): ok | ok | ok | ok | in softirq context: ok | ok | ok |FAILED| As a fix, add lockdep map for BH disabled section. This fixes the issue by letting us catch cases when local_bh_disable() gets called with preemption disabled where local_lock doesn't get acquired. In the case of "in softirq context" selftest, local_bh_disable() was being called with preemption disable as it's early in the boot. [ boqun: Move the lockdep annotations into __local_bh_*() to avoid false positives because of unpaired local_bh_disable() reported by Borislav Petkov and Peter Zijlstra, and make bh_lock_map only exist for PREEMPT_RT. ] [ mingo: Restored authorship and improved the bh_lock_map definition. ] Signed-off-by: Ryo Takakura <ryotkkr98@gmail.com> Signed-off-by: Boqun Feng <boqun.feng@gmail.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20250321143322.79651-1-boqun.feng@gmail.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-04tracing: Mark binary printing functions with __printf() attributeAndy Shevchenko
[ Upstream commit 196a062641fe68d9bfe0ad36b6cd7628c99ad22c ] Binary printing functions are using printf() type of format, and compiler is not happy about them as is: kernel/trace/trace.c:3292:9: error: function ‘trace_vbprintk’ might be a candidate for ‘gnu_printf’ format attribute [-Werror=suggest-attribute=format] kernel/trace/trace_seq.c:182:9: error: function ‘trace_seq_bprintf’ might be a candidate for ‘gnu_printf’ format attribute [-Werror=suggest-attribute=format] Fix the compilation errors by adding __printf() attribute. While at it, move existing __printf() attributes from the implementations to the declarations. IT also fixes incorrect attribute parameters that are used for trace_array_printk(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Kees Cook <kees@kernel.org> Reviewed-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20250321144822.324050-4-andriy.shevchenko@linux.intel.com Signed-off-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-04bpf: fix possible endless loop in BPF map iterationBrandon Kammerdiener
[ Upstream commit 75673fda0c557ae26078177dd14d4857afbf128d ] The _safe variant used here gets the next element before running the callback, avoiding the endless loop condition. Signed-off-by: Brandon Kammerdiener <brandon.kammerdiener@intel.com> Link: https://lore.kernel.org/r/20250424153246.141677-2-brandon.kammerdiener@intel.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Hou Tao <houtao1@huawei.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-04cgroup: Fix compilation issue due to cgroup_mutex not being exportedgaoxu
[ Upstream commit 87c259a7a359e73e6c52c68fcbec79988999b4e6 ] When adding folio_memcg function call in the zram module for Android16-6.12, the following error occurs during compilation: ERROR: modpost: "cgroup_mutex" [../soc-repo/zram.ko] undefined! This error is caused by the indirect call to lockdep_is_held(&cgroup_mutex) within folio_memcg. The export setting for cgroup_mutex is controlled by the CONFIG_PROVE_RCU macro. If CONFIG_LOCKDEP is enabled while CONFIG_PROVE_RCU is not, this compilation error will occur. To resolve this issue, add a parallel macro CONFIG_LOCKDEP control to ensure cgroup_mutex is properly exported when needed. Signed-off-by: gao xu <gaoxu2@honor.com> Acked-by: Michal Koutný <mkoutny@suse.com> Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-03Merge tag 'v6.6.87'Emanuele Ghidoli
Merge v6.6.87 stable release
2025-05-22ftrace: Fix preemption accounting for stacktrace filter commandpengdonglin
commit 11aff32439df6ca5b3b891b43032faf88f4a6a29 upstream. The preemption count of the stacktrace filter command to trace ksys_read is consistently incorrect: $ echo ksys_read:stacktrace > set_ftrace_filter <...>-453 [004] ...1. 38.308956: <stack trace> => ksys_read => do_syscall_64 => entry_SYSCALL_64_after_hwframe The root cause is that the trace framework disables preemption when invoking the filter command callback in function_trace_probe_call: preempt_disable_notrace(); probe_ops->func(ip, parent_ip, probe_opsbe->tr, probe_ops, probe->data); preempt_enable_notrace(); Use tracing_gen_ctx_dec() to account for the preempt_disable_notrace(), which will output the correct preemption count: $ echo ksys_read:stacktrace > set_ftrace_filter <...>-410 [006] ..... 31.420396: <stack trace> => ksys_read => do_syscall_64 => entry_SYSCALL_64_after_hwframe Cc: stable@vger.kernel.org Fixes: 36590c50b2d07 ("tracing: Merge irqflags + preempt counter.") Link: https://lore.kernel.org/20250512094246.1167956-2-dolinux.peng@gmail.com Signed-off-by: pengdonglin <dolinux.peng@gmail.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-05-22ftrace: Fix preemption accounting for stacktrace trigger commandpengdonglin
commit e333332657f615ac2b55aa35565c4a882018bbe9 upstream. When using the stacktrace trigger command to trace syscalls, the preemption count was consistently reported as 1 when the system call event itself had 0 ("."). For example: root@ubuntu22-vm:/sys/kernel/tracing/events/syscalls/sys_enter_read $ echo stacktrace > trigger $ echo 1 > enable sshd-416 [002] ..... 232.864910: sys_read(fd: a, buf: 556b1f3221d0, count: 8000) sshd-416 [002] ...1. 232.864913: <stack trace> => ftrace_syscall_enter => syscall_trace_enter => do_syscall_64 => entry_SYSCALL_64_after_hwframe The root cause is that the trace framework disables preemption in __DO_TRACE before invoking the trigger callback. Use the tracing_gen_ctx_dec() that will accommodate for the increase of the preemption count in __DO_TRACE when calling the callback. The result is the accurate reporting of: sshd-410 [004] ..... 210.117660: sys_read(fd: 4, buf: 559b725ba130, count: 40000) sshd-410 [004] ..... 210.117662: <stack trace> => ftrace_syscall_enter => syscall_trace_enter => do_syscall_64 => entry_SYSCALL_64_after_hwframe Cc: stable@vger.kernel.org Fixes: ce33c845b030c ("tracing: Dump stacktrace trigger to the corresponding instance") Link: https://lore.kernel.org/20250512094246.1167956-1-dolinux.peng@gmail.com Signed-off-by: pengdonglin <dolinux.peng@gmail.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-05-22tracing: probes: Fix a possible race in trace_probe_log APIsMasami Hiramatsu (Google)
[ Upstream commit fd837de3c9cb1a162c69bc1fb1f438467fe7f2f5 ] Since the shared trace_probe_log variable can be accessed and modified via probe event create operation of kprobe_events, uprobe_events, and dynamic_events, it should be protected. In the dynamic_events, all operations are serialized by `dyn_event_ops_mutex`. But kprobe_events and uprobe_events interfaces are not serialized. To solve this issue, introduces dyn_event_create(), which runs create() operation under the mutex, for kprobe_events and uprobe_events. This also uses lockdep to check the mutex is held when using trace_probe_log* APIs. Link: https://lore.kernel.org/all/174684868120.551552.3068655787654268804.stgit@devnote2/ Reported-by: Paul Cacheux <paulcacheux@gmail.com> Closes: https://lore.kernel.org/all/20250510074456.805a16872b591e2971a4d221@kernel.org/ Fixes: ab105a4fb894 ("tracing: Use tracing error_log with probe events") Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-05-22cgroup/cpuset: Extend kthread_is_per_cpu() check to all PF_NO_SETAFFINITY tasksWaiman Long
[ Upstream commit 39b5ef791d109dd54c7c2e6e87933edfcc0ad1ac ] Commit ec5fbdfb99d1 ("cgroup/cpuset: Enable update_tasks_cpumask() on top_cpuset") enabled us to pull CPUs dedicated to child partitions from tasks in top_cpuset by ignoring per cpu kthreads. However, there can be other kthreads that are not per cpu but have PF_NO_SETAFFINITY flag set to indicate that we shouldn't mess with their CPU affinity. For other kthreads, their affinity will be changed to skip CPUs dedicated to child partitions whether it is an isolating or a scheduling one. As all the per cpu kthreads have PF_NO_SETAFFINITY set, the PF_NO_SETAFFINITY tasks are essentially a superset of per cpu kthreads. Fix this issue by dropping the kthread_is_per_cpu() check and checking the PF_NO_SETAFFINITY flag instead. Fixes: ec5fbdfb99d1 ("cgroup/cpuset: Enable update_tasks_cpumask() on top_cpuset") Signed-off-by: Waiman Long <longman@redhat.com> Acked-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-05-18module: ensure that kobject_put() is safe for module type kobjectsDmitry Antipov
commit a6aeb739974ec73e5217c75a7c008a688d3d5cf1 upstream. In 'lookup_or_create_module_kobject()', an internal kobject is created using 'module_ktype'. So call to 'kobject_put()' on error handling path causes an attempt to use an uninitialized completion pointer in 'module_kobject_release()'. In this scenario, we just want to release kobject without an extra synchronization required for a regular module unloading process, so adding an extra check whether 'complete()' is actually required makes 'kobject_put()' safe. Reported-by: syzbot+7fb8a372e1f6add936dd@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=7fb8a372e1f6add936dd Fixes: 942e443127e9 ("module: Fix mod->mkobj.kobj potentially freed too early") Cc: stable@vger.kernel.org Suggested-by: Petr Pavlu <petr.pavlu@suse.com> Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru> Link: https://lore.kernel.org/r/20250507065044.86529-1-dmantipov@yandex.ru Signed-off-by: Petr Pavlu <petr.pavlu@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-05-09kernel: globalize lookup_or_create_module_kobject()Shyam Saini
[ Upstream commit 7c76c813cfc42a7376378a0c4b7250db2eebab81 ] lookup_or_create_module_kobject() is marked as static and __init, to make it global drop static keyword. Since this function can be called from non-init code, use __modinit instead of __init, __modinit marker will make it __init if CONFIG_MODULES is not defined. Suggested-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Shyam Saini <shyamsaini@linux.microsoft.com> Link: https://lore.kernel.org/r/20250227184930.34163-4-shyamsaini@linux.microsoft.com Signed-off-by: Petr Pavlu <petr.pavlu@suse.com> Stable-dep-of: f95bbfe18512 ("drivers: base: handle module_kobject creation") Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-05-09kernel: param: rename locate_module_kobjectShyam Saini
[ Upstream commit bbc9462f0cb0c8917a4908e856731708f0cee910 ] The locate_module_kobject() function looks up an existing module_kobject for a given module name. If it cannot find the corresponding module_kobject, it creates one for the given name. This commit renames locate_module_kobject() to lookup_or_create_module_kobject() to better describe its operations. This doesn't change anything functionality wise. Suggested-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Shyam Saini <shyamsaini@linux.microsoft.com> Link: https://lore.kernel.org/r/20250227184930.34163-2-shyamsaini@linux.microsoft.com Signed-off-by: Petr Pavlu <petr.pavlu@suse.com> Stable-dep-of: f95bbfe18512 ("drivers: base: handle module_kobject creation") Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-05-09bpf: fix null dereference when computing changes_pkt_data of prog w/o subprogsEduard Zingerman
commit ac6542ad92759cda383ad62b4e4cbfc28136abc1 upstream. bpf_prog_aux->func field might be NULL if program does not have subprograms except for main sub-program. The fixed commit does bpf_prog_aux->func access unconditionally, which might lead to null pointer dereference. The bug could be triggered by replacing the following BPF program: SEC("tc") int main_changes(struct __sk_buff *sk) { bpf_skb_pull_data(sk, 0); return 0; } With the following BPF program: SEC("freplace") long changes_pkt_data(struct __sk_buff *sk) { return bpf_skb_pull_data(sk, 0); } bpf_prog_aux instance itself represents the main sub-program, use this property to fix the bug. Fixes: 81f6d0530ba0 ("bpf: check changes_pkt_data property for extension programs") Reported-by: kernel test robot <lkp@intel.com> Reported-by: Dan Carpenter <dan.carpenter@linaro.org> Closes: https://lore.kernel.org/r/202412111822.qGw6tOyB-lkp@intel.com/ Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20241212070711.427443-1-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Shung-Hsi Yu <shung-hsi.yu@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-05-09bpf: check changes_pkt_data property for extension programsEduard Zingerman
commit 81f6d0530ba031b5f038a091619bf2ff29568852 upstream. When processing calls to global sub-programs, verifier decides whether to invalidate all packet pointers in current state depending on the changes_pkt_data property of the global sub-program. Because of this, an extension program replacing a global sub-program must be compatible with changes_pkt_data property of the sub-program being replaced. This commit: - adds changes_pkt_data flag to struct bpf_prog_aux: - this flag is set in check_cfg() for main sub-program; - in jit_subprogs() for other sub-programs; - modifies bpf_check_attach_btf_id() to check changes_pkt_data flag; - moves call to check_attach_btf_id() after the call to check_cfg(), because it needs changes_pkt_data flag to be set: bpf_check: ... ... - check_attach_btf_id resolve_pseudo_ldimm64 resolve_pseudo_ldimm64 --> bpf_prog_is_offloaded bpf_prog_is_offloaded check_cfg check_cfg + check_attach_btf_id ... ... The following fields are set by check_attach_btf_id(): - env->ops - prog->aux->attach_btf_trace - prog->aux->attach_func_name - prog->aux->attach_func_proto - prog->aux->dst_trampoline - prog->aux->mod - prog->aux->saved_dst_attach_type - prog->aux->saved_dst_prog_type - prog->expected_attach_type Neither of these fields are used by resolve_pseudo_ldimm64() or bpf_prog_offload_verifier_prep() (for netronome and netdevsim drivers), so the reordering is safe. Suggested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com> Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20241210041100.1898468-6-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> [ shung-hsi.yu: adapt to missing fields in "struct bpf_prog_aux". Context difference in jit_subprogs() because BPF Exception is not supported. Context difference in bpf_check() because commit 5b5f51bff1b6 "bpf: no_caller_saved_registers attribute for helper calls" is not present. ] Signed-off-by: Shung-Hsi Yu <shung-hsi.yu@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-05-09bpf: track changes_pkt_data property for global functionsEduard Zingerman
commit 51081a3f25c742da5a659d7fc6fd77ebfdd555be upstream. When processing calls to certain helpers, verifier invalidates all packet pointers in a current state. For example, consider the following program: __attribute__((__noinline__)) long skb_pull_data(struct __sk_buff *sk, __u32 len) { return bpf_skb_pull_data(sk, len); } SEC("tc") int test_invalidate_checks(struct __sk_buff *sk) { int *p = (void *)(long)sk->data; if ((void *)(p + 1) > (void *)(long)sk->data_end) return TCX_DROP; skb_pull_data(sk, 0); *p = 42; return TCX_PASS; } After a call to bpf_skb_pull_data() the pointer 'p' can't be used safely. See function filter.c:bpf_helper_changes_pkt_data() for a list of such helpers. At the moment verifier invalidates packet pointers when processing helper function calls, and does not traverse global sub-programs when processing calls to global sub-programs. This means that calls to helpers done from global sub-programs do not invalidate pointers in the caller state. E.g. the program above is unsafe, but is not rejected by verifier. This commit fixes the omission by computing field bpf_subprog_info->changes_pkt_data for each sub-program before main verification pass. changes_pkt_data should be set if: - subprogram calls helper for which bpf_helper_changes_pkt_data returns true; - subprogram calls a global function, for which bpf_subprog_info->changes_pkt_data should be set. The verifier.c:check_cfg() pass is modified to compute this information. The commit relies on depth first instruction traversal done by check_cfg() and absence of recursive function calls: - check_cfg() would eventually visit every call to subprogram S in a state when S is fully explored; - when S is fully explored: - every direct helper call within S is explored (and thus changes_pkt_data is set if needed); - every call to subprogram S1 called by S was visited with S1 fully explored (and thus S inherits changes_pkt_data from S1). The downside of such approach is that dead code elimination is not taken into account: if a helper call inside global function is dead because of current configuration, verifier would conservatively assume that the call occurs for the purpose of the changes_pkt_data computation. Reported-by: Nick Zavaritsky <mejedi@gmail.com> Closes: https://lore.kernel.org/bpf/0498CA22-5779-4767-9C0C-A9515CEA711F@gmail.com/ Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20241210041100.1898468-4-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> [shung-hsi.yu: do not use bitfield in "struct bpf_subprog_info" because commit 406a6fa44bfb ("bpf: use bitfields for simple per-subprog bool flags") is not present and minor context difference in check_func_call() because commit 491dd8edecbc ("bpf: Emit global subprog name in verifier logs") is not present. ] Signed-off-by: Shung-Hsi Yu <shung-hsi.yu@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-05-09bpf: refactor bpf_helper_changes_pkt_data to use helper numberEduard Zingerman
commit b238e187b4a2d3b54d80aec05a9cab6466b79dde upstream. Use BPF helper number instead of function pointer in bpf_helper_changes_pkt_data(). This would simplify usage of this function in verifier.c:check_cfg() (in a follow-up patch), where only helper number is easily available and there is no real need to lookup helper proto. Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20241210041100.1898468-3-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Shung-Hsi Yu <shung-hsi.yu@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-05-09bpf: add find_containing_subprog() utility functionEduard Zingerman
commit 27e88bc4df1d80888fe1aaca786a7cc6e69587e2 upstream. Add a utility function, looking for a subprogram containing a given instruction index, rewrite find_subprog() to use this function. Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20241210041100.1898468-2-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Shung-Hsi Yu <shung-hsi.yu@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-05-09tracing: Fix oob write in trace_seq_to_buffer()Jeongjun Park
commit f5178c41bb43444a6008150fe6094497135d07cb upstream. syzbot reported this bug: ================================================================== BUG: KASAN: slab-out-of-bounds in trace_seq_to_buffer kernel/trace/trace.c:1830 [inline] BUG: KASAN: slab-out-of-bounds in tracing_splice_read_pipe+0x6be/0xdd0 kernel/trace/trace.c:6822 Write of size 4507 at addr ffff888032b6b000 by task syz.2.320/7260 CPU: 1 UID: 0 PID: 7260 Comm: syz.2.320 Not tainted 6.15.0-rc1-syzkaller-00301-g3bde70a2c827 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0xc3/0x670 mm/kasan/report.c:521 kasan_report+0xe0/0x110 mm/kasan/report.c:634 check_region_inline mm/kasan/generic.c:183 [inline] kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189 __asan_memcpy+0x3c/0x60 mm/kasan/shadow.c:106 trace_seq_to_buffer kernel/trace/trace.c:1830 [inline] tracing_splice_read_pipe+0x6be/0xdd0 kernel/trace/trace.c:6822 .... ================================================================== It has been reported that trace_seq_to_buffer() tries to copy more data than PAGE_SIZE to buf. Therefore, to prevent this, we should use the smaller of trace_seq_used(&iter->seq) and PAGE_SIZE as an argument. Link: https://lore.kernel.org/20250422113026.13308-1-aha310510@gmail.com Reported-by: syzbot+c8cd2d2c412b868263fb@syzkaller.appspotmail.com Fixes: 3c56819b14b0 ("tracing: splice support for tracing_pipe") Suggested-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Jeongjun Park <aha310510@gmail.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-05-09tracing: Do not take trace_event_sem in print_event_fields()Steven Rostedt
commit 0a8f11f8569e7ed16cbcedeb28c4350f6378fea6 upstream. On some paths in print_event_fields() it takes the trace_event_sem for read, even though it should always be held when the function is called. Remove the taking of that mutex and add a lockdep_assert_held_read() to make sure the trace_event_sem is held when print_event_fields() is called. Cc: stable@vger.kernel.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Link: https://lore.kernel.org/20250501224128.0b1f0571@batman.local.home Fixes: 80a76994b2d88 ("tracing: Add "fields" option to show raw trace event fields") Reported-by: syzbot+441582c1592938fccf09@syzkaller.appspotmail.com Closes: https://lore.kernel.org/all/6813ff5e.050a0220.14dd7d.001b.GAE@google.com/ Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-05-02timekeeping: Add a lockdep override in tick_freeze()Sebastian Andrzej Siewior
[ Upstream commit 92e250c624ea37fde64bfd624fd2556f0d846f18 ] tick_freeze() acquires a raw spinlock (tick_freeze_lock). Later in the callchain (timekeeping_suspend() -> mc146818_avoid_UIP()) the RTC driver acquires a spinlock which becomes a sleeping lock on PREEMPT_RT. Lockdep complains about this lock nesting. Add a lockdep override for this special case and a comment explaining why it is okay. Reported-by: Borislav Petkov <bp@alien8.de> Reported-by: Chris Bainbridge <chris.bainbridge@gmail.com> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/all/20250404133429.pnAzf-eF@linutronix.de Closes: https://lore.kernel.org/all/20250330113202.GAZ-krsjAnurOlTcp-@fat_crate.local/ Closes: https://lore.kernel.org/all/CAP-bSRZ0CWyZZsMtx046YV8L28LhY0fson2g4EqcwRAVN1Jk+Q@mail.gmail.com/ Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-05-02perf/core: Fix WARN_ON(!ctx) in __free_event() for partial initGabriel Shahrouzi
[ Upstream commit 0ba3a4ab76fd3367b9cb680cad70182c896c795c ] Move the get_ctx(child_ctx) call and the child_event->ctx assignment to occur immediately after the child event is allocated. Ensure that child_event->ctx is non-NULL before any subsequent error path within inherit_event calls free_event(), satisfying the assumptions of the cleanup code. Details: There's no clear Fixes tag, because this bug is a side-effect of multiple interacting commits over time (up to 15 years old), not a single regression. The code initially incremented refcount then assigned context immediately after the child_event was created. Later, an early validity check for child_event was added before the refcount/assignment. Even later, a WARN_ON_ONCE() cleanup check was added, assuming event->ctx is valid if the pmu_ctx is valid. The problem is that the WARN_ON_ONCE() could trigger after the initial check passed but before child_event->ctx was assigned, violating its precondition. The solution is to assign child_event->ctx right after its initial validation. This ensures the context exists for any subsequent checks or cleanup routines, resolving the WARN_ON_ONCE(). To resolve it, defer the refcount update and child_event->ctx assignment directly after child_event->pmu_ctx is set but before checking if the parent event is orphaned. The cleanup routine depends on event->pmu_ctx being non-NULL before it verifies event->ctx is non-NULL. This also maintains the author's original intent of passing in child_ctx to find_get_pmu_context before its refcount/assignment. [ mingo: Expanded the changelog from another email by Gabriel Shahrouzi. ] Reported-by: syzbot+ff3aa851d46ab82953a3@syzkaller.appspotmail.com Signed-off-by: Gabriel Shahrouzi <gshahrouzi@gmail.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Bangoria <ravi.bangoria@amd.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Link: https://lore.kernel.org/r/20250405203036.582721-1-gshahrouzi@gmail.com Closes: https://syzkaller.appspot.com/bug?extid=ff3aa851d46ab82953a3 Signed-off-by: Sasha Levin <sashal@kernel.org>