From 2c223f7239f376a90d71903ec474ba887cf21d94 Mon Sep 17 00:00:00 2001 From: Oreoluwa Babatunde Date: Wed, 6 Aug 2025 10:24:21 -0700 Subject: of: reserved_mem: Restructure call site for dma_contiguous_early_fixup() Restructure the call site for dma_contiguous_early_fixup() to where the reserved_mem nodes are being parsed from the DT so that dma_mmu_remap[] is populated before dma_contiguous_remap() is called. Fixes: 8a6e02d0c00e ("of: reserved_mem: Restructure how the reserved memory regions are processed") Signed-off-by: Oreoluwa Babatunde Tested-by: William Zhang Signed-off-by: Marek Szyprowski Link: https://lore.kernel.org/r/20250806172421.2748302-1-oreoluwa.babatunde@oss.qualcomm.com --- kernel/dma/contiguous.c | 2 -- 1 file changed, 2 deletions(-) (limited to 'kernel') diff --git a/kernel/dma/contiguous.c b/kernel/dma/contiguous.c index 67af8a55185d..d9b9dcba6ff7 100644 --- a/kernel/dma/contiguous.c +++ b/kernel/dma/contiguous.c @@ -483,8 +483,6 @@ static int __init rmem_cma_setup(struct reserved_mem *rmem) pr_err("Reserved memory: unable to setup CMA region\n"); return err; } - /* Architecture specific contiguous memory fixup. */ - dma_contiguous_early_fixup(rmem->base, rmem->size); if (default_cma) dma_contiguous_default_area = cma; -- cgit v1.2.3 From 89a2d212bdb4bc29bed8e7077abe054b801137ea Mon Sep 17 00:00:00 2001 From: Shanker Donthineni Date: Mon, 11 Aug 2025 13:17:59 -0500 Subject: dma/pool: Ensure DMA_DIRECT_REMAP allocations are decrypted When CONFIG_DMA_DIRECT_REMAP is enabled, atomic pool pages are remapped via dma_common_contiguous_remap() using the supplied pgprot. Currently, the mapping uses pgprot_dmacoherent(PAGE_KERNEL), which leaves the memory encrypted on systems with memory encryption enabled (e.g., ARM CCA Realms). This can cause the DMA layer to fail or crash when accessing the memory, as the underlying physical pages are not configured as expected. Fix this by requesting a decrypted mapping in the vmap() call: pgprot_decrypted(pgprot_dmacoherent(PAGE_KERNEL)) This ensures that atomic pool memory is consistently mapped unencrypted. Cc: stable@vger.kernel.org Signed-off-by: Shanker Donthineni Reviewed-by: Catalin Marinas Signed-off-by: Marek Szyprowski Link: https://lore.kernel.org/r/20250811181759.998805-1-sdonthineni@nvidia.com --- kernel/dma/pool.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'kernel') diff --git a/kernel/dma/pool.c b/kernel/dma/pool.c index 7b04f7575796..ee45dee33d49 100644 --- a/kernel/dma/pool.c +++ b/kernel/dma/pool.c @@ -102,8 +102,8 @@ static int atomic_pool_expand(struct gen_pool *pool, size_t pool_size, #ifdef CONFIG_DMA_DIRECT_REMAP addr = dma_common_contiguous_remap(page, pool_size, - pgprot_dmacoherent(PAGE_KERNEL), - __builtin_return_address(0)); + pgprot_decrypted(pgprot_dmacoherent(PAGE_KERNEL)), + __builtin_return_address(0)); if (!addr) goto free_page; #else -- cgit v1.2.3 From 2b986b9e917bc88f81aa1ed386af63b26c983f1d Mon Sep 17 00:00:00 2001 From: Jesper Dangaard Brouer Date: Thu, 14 Aug 2025 20:24:37 +0200 Subject: bpf, cpumap: Disable page_pool direct xdp_return need larger scope When running an XDP bpf_prog on the remote CPU in cpumap code then we must disable the direct return optimization that xdp_return can perform for mem_type page_pool. This optimization assumes code is still executing under RX-NAPI of the original receiving CPU, which isn't true on this remote CPU. The cpumap code already disabled this via helpers xdp_set_return_frame_no_direct() and xdp_clear_return_frame_no_direct(), but the scope didn't include xdp_do_flush(). When doing XDP_REDIRECT towards e.g devmap this causes the function bq_xmit_all() to run with direct return optimization enabled. This can lead to hard to find bugs. The issue only happens when bq_xmit_all() cannot ndo_xdp_xmit all frames and them frees them via xdp_return_frame_rx_napi(). Fix by expanding scope to include xdp_do_flush(). This was found by Dragos Tatulea. Fixes: 11941f8a8536 ("bpf: cpumap: Implement generic cpumap") Reported-by: Dragos Tatulea Reported-by: Chris Arges Signed-off-by: Jesper Dangaard Brouer Signed-off-by: Martin KaFai Lau Signed-off-by: Daniel Borkmann Tested-by: Chris Arges Link: https://patch.msgid.link/175519587755.3008742.1088294435150406835.stgit@firesoul --- kernel/bpf/cpumap.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'kernel') diff --git a/kernel/bpf/cpumap.c b/kernel/bpf/cpumap.c index b2b7b8ec2c2a..c46360b27871 100644 --- a/kernel/bpf/cpumap.c +++ b/kernel/bpf/cpumap.c @@ -186,7 +186,6 @@ static int cpu_map_bpf_prog_run_xdp(struct bpf_cpu_map_entry *rcpu, struct xdp_buff xdp; int i, nframes = 0; - xdp_set_return_frame_no_direct(); xdp.rxq = &rxq; for (i = 0; i < n; i++) { @@ -231,7 +230,6 @@ static int cpu_map_bpf_prog_run_xdp(struct bpf_cpu_map_entry *rcpu, } } - xdp_clear_return_frame_no_direct(); stats->pass += nframes; return nframes; @@ -255,6 +253,7 @@ static void cpu_map_bpf_prog_run(struct bpf_cpu_map_entry *rcpu, void **frames, rcu_read_lock(); bpf_net_ctx = bpf_net_ctx_set(&__bpf_net_ctx); + xdp_set_return_frame_no_direct(); ret->xdp_n = cpu_map_bpf_prog_run_xdp(rcpu, frames, ret->xdp_n, stats); if (unlikely(ret->skb_n)) @@ -264,6 +263,7 @@ static void cpu_map_bpf_prog_run(struct bpf_cpu_map_entry *rcpu, void **frames, if (stats->redirect) xdp_do_flush(); + xdp_clear_return_frame_no_direct(); bpf_net_ctx_clear(bpf_net_ctx); rcu_read_unlock(); -- cgit v1.2.3 From e4414b01c1cd9887bbde92f946c1ba94e40d6d64 Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Thu, 14 Aug 2025 22:06:55 +0200 Subject: bpf: Check the helper function is valid in get_helper_proto kernel test robot reported verifier bug [1] where the helper func pointer could be NULL due to disabled config option. As Alexei suggested we could check on that in get_helper_proto directly. Marking tail_call helper func with BPF_PTR_POISON, because it is unused by design. [1] https://lore.kernel.org/oe-lkp/202507160818.68358831-lkp@intel.com Reported-by: kernel test robot Reported-by: syzbot+a9ed3d9132939852d0df@syzkaller.appspotmail.com Suggested-by: Alexei Starovoitov Signed-off-by: Jiri Olsa Signed-off-by: Daniel Borkmann Acked-by: Paul Chaignon Acked-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20250814200655.945632-1-jolsa@kernel.org Closes: https://lore.kernel.org/oe-lkp/202507160818.68358831-lkp@intel.com --- kernel/bpf/core.c | 5 ++++- kernel/bpf/verifier.c | 2 +- 2 files changed, 5 insertions(+), 2 deletions(-) (limited to 'kernel') diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index 5d1650af899d..f8ac77d08ca7 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -3024,7 +3024,10 @@ EXPORT_SYMBOL_GPL(bpf_event_output); /* Always built-in helper functions. */ const struct bpf_func_proto bpf_tail_call_proto = { - .func = NULL, + /* func is unused for tail_call, we set it to pass the + * get_helper_proto check + */ + .func = BPF_PTR_POISON, .gpl_only = false, .ret_type = RET_VOID, .arg1_type = ARG_PTR_TO_CTX, diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index c4f69a9e9af6..c89e2b1bc644 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -11354,7 +11354,7 @@ static int get_helper_proto(struct bpf_verifier_env *env, int func_id, return -EINVAL; *ptr = env->ops->get_func_proto(func_id, env->prog); - return *ptr ? 0 : -EINVAL; + return *ptr && (*ptr)->func ? 0 : -EINVAL; } static int check_helper_call(struct bpf_verifier_env *env, struct bpf_insn *insn, -- cgit v1.2.3 From 4717432dfd99bbd015b6782adca216c6f9340038 Mon Sep 17 00:00:00 2001 From: Huacai Chen Date: Sat, 9 Aug 2025 21:04:19 +0800 Subject: sched/deadline: Fix dl_server_stopped() Commit cccb45d7c429 ("sched/deadline: Less agressive dl_server handling") introduces dl_server_stopped(). But it is obvious that dl_server_stopped() should return true if dl_se->dl_server_active is 0. Fixes: cccb45d7c429 ("sched/deadline: Less agressive dl_server handling") Signed-off-by: Huacai Chen Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/20250809130419.1980742-1-chenhuacai@loongson.cn --- kernel/sched/deadline.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel') diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c index e2d51f4306b3..bb813afe5b08 100644 --- a/kernel/sched/deadline.c +++ b/kernel/sched/deadline.c @@ -1611,7 +1611,7 @@ void dl_server_stop(struct sched_dl_entity *dl_se) static bool dl_server_stopped(struct sched_dl_entity *dl_se) { if (!dl_se->dl_server_active) - return false; + return true; if (dl_se->dl_server_idle) { dl_server_stop(dl_se); -- cgit v1.2.3 From bb4700adc3abec34c0a38b64f66258e4e233fc16 Mon Sep 17 00:00:00 2001 From: Juri Lelli Date: Mon, 21 Jul 2025 15:01:42 +0200 Subject: sched/deadline: Always stop dl-server before changing parameters Commit cccb45d7c4295 ("sched/deadline: Less agressive dl_server handling") reduced dl-server overhead by delaying disabling servers only after there are no fair task around for a whole period, which means that deadline entities are not dequeued right away on a server stop event. However, the delay opens up a window in which a request for changing server parameters can break per-runqueue running_bw tracking, as reported by Yuri. Close the problematic window by unconditionally calling dl_server_stop() before applying the new parameters (ensuring deadline entities go through an actual dequeue). Fixes: cccb45d7c4295 ("sched/deadline: Less agressive dl_server handling") Reported-by: Yuri Andriaccio Signed-off-by: Juri Lelli Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Valentin Schneider Link: https://lore.kernel.org/r/20250721-upstream-fix-dlserver-lessaggressive-b4-v1-1-4ebc10c87e40@redhat.com --- kernel/sched/debug.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) (limited to 'kernel') diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c index 3f06ab84d53f..02e16b70a790 100644 --- a/kernel/sched/debug.c +++ b/kernel/sched/debug.c @@ -376,10 +376,8 @@ static ssize_t sched_fair_server_write(struct file *filp, const char __user *ubu return -EINVAL; } - if (rq->cfs.h_nr_queued) { - update_rq_clock(rq); - dl_server_stop(&rq->fair_server); - } + update_rq_clock(rq); + dl_server_stop(&rq->fair_server); retval = dl_server_apply_params(&rq->fair_server, runtime, period, 0); if (retval) -- cgit v1.2.3 From 421fc59cf58c64f898cafbbbbda0bc705837e7df Mon Sep 17 00:00:00 2001 From: kuyo chang Date: Sun, 15 Jun 2025 21:10:56 +0800 Subject: sched/deadline: Fix RT task potential starvation when expiry time passed [Symptom] The fair server mechanism, which is intended to prevent fair starvation when higher-priority tasks monopolize the CPU. Specifically, RT tasks on the runqueue may not be scheduled as expected. [Analysis] The log "sched: DL replenish lagged too much" triggered. By memory dump of dl_server: curr = 0xFFFFFF80D6A0AC00 ( dl_server = 0xFFFFFF83CD5B1470( dl_runtime = 0x02FAF080, dl_deadline = 0x3B9ACA00, dl_period = 0x3B9ACA00, dl_bw = 0xCCCC, dl_density = 0xCCCC, runtime = 0x02FAF080, deadline = 0x0000082031EB0E80, flags = 0x0, dl_throttled = 0x0, dl_yielded = 0x0, dl_non_contending = 0x0, dl_overrun = 0x0, dl_server = 0x1, dl_server_active = 0x1, dl_defer = 0x1, dl_defer_armed = 0x0, dl_defer_running = 0x1, dl_timer = ( node = ( expires = 0x000008199756E700), _softexpires = 0x000008199756E700, function = 0xFFFFFFDB9AF44D30 = dl_task_timer, base = 0xFFFFFF83CD5A12C0, state = 0x0, is_rel = 0x0, is_soft = 0x0, clock_update_flags = 0x4, clock = 0x000008204A496900, - The timer expiration time (rq->curr->dl_server->dl_timer->expires) is already in the past, indicating the timer has expired. - The timer state (rq->curr->dl_server->dl_timer->state) is 0. [Suspected Root Cause] The relevant code flow in the throttle path of update_curr_dl_se() as follows: dequeue_dl_entity(dl_se, 0); // the DL entity is dequeued if (unlikely(is_dl_boosted(dl_se) || !start_dl_timer(dl_se))) { if (dl_server(dl_se)) // timer registration fails enqueue_dl_entity(dl_se, ENQUEUE_REPLENISH);//enqueue immediately ... } The failure of `start_dl_timer` is caused by attempting to register a timer with an expiration time that is already in the past. When this situation persists, the code repeatedly re-enqueues the DL entity without properly replenishing or restarting the timer, resulting in RT task may not be scheduled as expected. [Proposed Solution]: Instead of immediately re-enqueuing the DL entity on timer registration failure, this change ensures the DL entity is properly replenished and the timer is restarted, preventing RT potential starvation. Fixes: 63ba8422f876 ("sched/deadline: Introduce deadline servers") Signed-off-by: kuyo chang Signed-off-by: Peter Zijlstra (Intel) Closes: https://lore.kernel.org/CAMuHMdXn4z1pioTtBGMfQM0jsLviqS2jwysaWXpoLxWYoGa82w@mail.gmail.com Tested-by: Geert Uytterhoeven Tested-by: Jiri Slaby Tested-by: Diederik de Haas Link: https://lkml.kernel.org/r/20250615131129.954975-1-kuyo.chang@mediatek.com --- kernel/sched/deadline.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) (limited to 'kernel') diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c index bb813afe5b08..88c3bd64a8a0 100644 --- a/kernel/sched/deadline.c +++ b/kernel/sched/deadline.c @@ -1496,10 +1496,12 @@ throttle: } if (unlikely(is_dl_boosted(dl_se) || !start_dl_timer(dl_se))) { - if (dl_server(dl_se)) - enqueue_dl_entity(dl_se, ENQUEUE_REPLENISH); - else + if (dl_server(dl_se)) { + replenish_dl_new_period(dl_se, rq); + start_dl_timer(dl_se); + } else { enqueue_task_dl(rq, dl_task_of(dl_se), ENQUEUE_REPLENISH); + } } if (!is_leftmost(dl_se, &rq->dl)) -- cgit v1.2.3 From 52d15521eb75f9b521744db675bee61025d2fa52 Mon Sep 17 00:00:00 2001 From: Yicong Yang Date: Fri, 27 Jun 2025 11:54:20 +0800 Subject: sched/deadline: Don't count nr_running for dl_server proxy tasks On CPU offline the kernel stalled with below call trace: INFO: task kworker/0:1:11 blocked for more than 120 seconds. cpuhp hold the cpu hotplug lock endless and stalled vmstat_shepherd. This is because we count nr_running twice on cpuhp enqueuing and failed the wait condition of cpuhp: enqueue_task_fair() // pick cpuhp from idle, rq->nr_running = 0 dl_server_start() [...] add_nr_running() // rq->nr_running = 1 add_nr_running() // rq->nr_running = 2 [switch to cpuhp, waiting on balance_hotplug_wait()] rcuwait_wait_event(rq->nr_running == 1 && ...) // failed, rq->nr_running=2 schedule() // wait again It doesn't make sense to count the dl_server towards runnable tasks, since it runs other tasks. Fixes: 63ba8422f876 ("sched/deadline: Introduce deadline servers") Signed-off-by: Yicong Yang Signed-off-by: Peter Zijlstra (Intel) Link: https://lore.kernel.org/r/20250627035420.37712-1-yangyicong@huawei.com --- kernel/sched/deadline.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) (limited to 'kernel') diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c index 88c3bd64a8a0..f25301267e47 100644 --- a/kernel/sched/deadline.c +++ b/kernel/sched/deadline.c @@ -1851,7 +1851,9 @@ void inc_dl_tasks(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq) u64 deadline = dl_se->deadline; dl_rq->dl_nr_running++; - add_nr_running(rq_of_dl_rq(dl_rq), 1); + + if (!dl_server(dl_se)) + add_nr_running(rq_of_dl_rq(dl_rq), 1); inc_dl_deadline(dl_rq, deadline); } @@ -1861,7 +1863,9 @@ void dec_dl_tasks(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq) { WARN_ON(!dl_rq->dl_nr_running); dl_rq->dl_nr_running--; - sub_nr_running(rq_of_dl_rq(dl_rq), 1); + + if (!dl_server(dl_se)) + sub_nr_running(rq_of_dl_rq(dl_rq), 1); dec_dl_deadline(dl_rq, dl_se->deadline); } -- cgit v1.2.3 From d9b05321e21e4b218de4ce8a590bf375f58b6346 Mon Sep 17 00:00:00 2001 From: Sebastian Andrzej Siewior Date: Fri, 22 Aug 2025 16:12:38 +0200 Subject: futex: Move futex_hash_free() back to __mmput() To avoid a memory leak via mm_alloc() + mmdrop() the futex cleanup code has been moved to __mmdrop(). This resulted in a warnings if the futex hash table has been allocated via vmalloc() the mmdrop() was invoked from atomic context. The free path must stay in __mmput() to ensure it is invoked from preemptible context. In order to avoid the memory leak, delay the allocation of mm_struct::mm->futex_ref to futex_hash_allocate(). This works because neither the per-CPU counter nor the private hash has been allocated and therefore - futex_private_hash() callers (such as exit_pi_state_list()) don't acquire reference if there is no private hash yet. There is also no reference put. - Regular callers (futex_hash()) fallback to global hash. No reference counting here. The futex_ref member can be allocated in futex_hash_allocate() before the private hash itself is allocated. This happens either while the first thread is created or on request. In both cases the process has just a single thread so there can be either futex operation in progress or the request to create a private hash. Move futex_hash_free() back to __mmput(); Move the allocation of mm_struct::futex_ref to futex_hash_allocate(). [ bp: Fold a follow-up fix to prevent a use-after-free: https://lore.kernel.org/r/20250830213806.sEKuuGSm@linutronix.de ] Fixes: e703b7e247503 ("futex: Move futex cleanup to __mmdrop()") Closes: https://lore.kernel.org/all/20250821102721.6deae493@kernel.org/ Reported-by: Jakub Kicinski Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Borislav Petkov (AMD) Link: https://lkml.kernel.org/r/20250822141238.PfnkTjFb@linutronix.de --- kernel/fork.c | 2 +- kernel/futex/core.c | 16 ++++++++++++---- 2 files changed, 13 insertions(+), 5 deletions(-) (limited to 'kernel') diff --git a/kernel/fork.c b/kernel/fork.c index af673856499d..c4ada32598bd 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -689,7 +689,6 @@ void __mmdrop(struct mm_struct *mm) mm_pasid_drop(mm); mm_destroy_cid(mm); percpu_counter_destroy_many(mm->rss_stat, NR_MM_COUNTERS); - futex_hash_free(mm); free_mm(mm); } @@ -1138,6 +1137,7 @@ static inline void __mmput(struct mm_struct *mm) if (mm->binfmt) module_put(mm->binfmt->module); lru_gen_del_mm(mm); + futex_hash_free(mm); mmdrop(mm); } diff --git a/kernel/futex/core.c b/kernel/futex/core.c index d9bb5567af0c..125804fbb5cb 100644 --- a/kernel/futex/core.c +++ b/kernel/futex/core.c @@ -1722,12 +1722,9 @@ int futex_mm_init(struct mm_struct *mm) RCU_INIT_POINTER(mm->futex_phash, NULL); mm->futex_phash_new = NULL; /* futex-ref */ + mm->futex_ref = NULL; atomic_long_set(&mm->futex_atomic, 0); mm->futex_batches = get_state_synchronize_rcu(); - mm->futex_ref = alloc_percpu(unsigned int); - if (!mm->futex_ref) - return -ENOMEM; - this_cpu_inc(*mm->futex_ref); /* 0 -> 1 */ return 0; } @@ -1801,6 +1798,17 @@ static int futex_hash_allocate(unsigned int hash_slots, unsigned int flags) } } + if (!mm->futex_ref) { + /* + * This will always be allocated by the first thread and + * therefore requires no locking. + */ + mm->futex_ref = alloc_percpu(unsigned int); + if (!mm->futex_ref) + return -ENOMEM; + this_cpu_inc(*mm->futex_ref); /* 0 -> 1 */ + } + fph = kvzalloc(struct_size(fph, queues, hash_slots), GFP_KERNEL_ACCOUNT | __GFP_NOWARN); if (!fph) -- cgit v1.2.3 From 7e2368a21741e2db542330b32aa6fdd8908e7cff Mon Sep 17 00:00:00 2001 From: Baochen Qiang Date: Thu, 28 Aug 2025 16:17:33 +0800 Subject: dma-debug: don't enforce dma mapping check on noncoherent allocations As discussed in [1], there is no need to enforce dma mapping check on noncoherent allocations, a simple test on the returned CPU address is good enough. Add a new pair of debug helpers and use them for noncoherent alloc/free to fix this issue. Fixes: efa70f2fdc84 ("dma-mapping: add a new dma_alloc_pages API") Link: https://lore.kernel.org/all/ff6c1fe6-820f-4e58-8395-df06aa91706c@oss.qualcomm.com # 1 Signed-off-by: Baochen Qiang Signed-off-by: Marek Szyprowski Link: https://lore.kernel.org/r/20250828-dma-debug-fix-noncoherent-dma-check-v1-1-76e9be0dd7fc@oss.qualcomm.com --- kernel/dma/debug.c | 48 +++++++++++++++++++++++++++++++++++++++++++++++- kernel/dma/debug.h | 20 ++++++++++++++++++++ kernel/dma/mapping.c | 4 ++-- 3 files changed, 69 insertions(+), 3 deletions(-) (limited to 'kernel') diff --git a/kernel/dma/debug.c b/kernel/dma/debug.c index e43c6de2bce4..b82399437db0 100644 --- a/kernel/dma/debug.c +++ b/kernel/dma/debug.c @@ -39,6 +39,7 @@ enum { dma_debug_sg, dma_debug_coherent, dma_debug_resource, + dma_debug_noncoherent, }; enum map_err_types { @@ -141,6 +142,7 @@ static const char *type2name[] = { [dma_debug_sg] = "scatter-gather", [dma_debug_coherent] = "coherent", [dma_debug_resource] = "resource", + [dma_debug_noncoherent] = "noncoherent", }; static const char *dir2name[] = { @@ -993,7 +995,8 @@ static void check_unmap(struct dma_debug_entry *ref) "[mapped as %s] [unmapped as %s]\n", ref->dev_addr, ref->size, type2name[entry->type], type2name[ref->type]); - } else if (entry->type == dma_debug_coherent && + } else if ((entry->type == dma_debug_coherent || + entry->type == dma_debug_noncoherent) && ref->paddr != entry->paddr) { err_printk(ref->dev, entry, "device driver frees " "DMA memory with different CPU address " @@ -1581,6 +1584,49 @@ void debug_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg, } } +void debug_dma_alloc_pages(struct device *dev, struct page *page, + size_t size, int direction, + dma_addr_t dma_addr, + unsigned long attrs) +{ + struct dma_debug_entry *entry; + + if (unlikely(dma_debug_disabled())) + return; + + entry = dma_entry_alloc(); + if (!entry) + return; + + entry->type = dma_debug_noncoherent; + entry->dev = dev; + entry->paddr = page_to_phys(page); + entry->size = size; + entry->dev_addr = dma_addr; + entry->direction = direction; + + add_dma_entry(entry, attrs); +} + +void debug_dma_free_pages(struct device *dev, struct page *page, + size_t size, int direction, + dma_addr_t dma_addr) +{ + struct dma_debug_entry ref = { + .type = dma_debug_noncoherent, + .dev = dev, + .paddr = page_to_phys(page), + .dev_addr = dma_addr, + .size = size, + .direction = direction, + }; + + if (unlikely(dma_debug_disabled())) + return; + + check_unmap(&ref); +} + static int __init dma_debug_driver_setup(char *str) { int i; diff --git a/kernel/dma/debug.h b/kernel/dma/debug.h index f525197d3cae..48757ca13f31 100644 --- a/kernel/dma/debug.h +++ b/kernel/dma/debug.h @@ -54,6 +54,13 @@ extern void debug_dma_sync_sg_for_cpu(struct device *dev, extern void debug_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg, int nelems, int direction); +extern void debug_dma_alloc_pages(struct device *dev, struct page *page, + size_t size, int direction, + dma_addr_t dma_addr, + unsigned long attrs); +extern void debug_dma_free_pages(struct device *dev, struct page *page, + size_t size, int direction, + dma_addr_t dma_addr); #else /* CONFIG_DMA_API_DEBUG */ static inline void debug_dma_map_page(struct device *dev, struct page *page, size_t offset, size_t size, @@ -126,5 +133,18 @@ static inline void debug_dma_sync_sg_for_device(struct device *dev, int nelems, int direction) { } + +static inline void debug_dma_alloc_pages(struct device *dev, struct page *page, + size_t size, int direction, + dma_addr_t dma_addr, + unsigned long attrs) +{ +} + +static inline void debug_dma_free_pages(struct device *dev, struct page *page, + size_t size, int direction, + dma_addr_t dma_addr) +{ +} #endif /* CONFIG_DMA_API_DEBUG */ #endif /* _KERNEL_DMA_DEBUG_H */ diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c index 107e4a4d251d..56de28a3b179 100644 --- a/kernel/dma/mapping.c +++ b/kernel/dma/mapping.c @@ -712,7 +712,7 @@ struct page *dma_alloc_pages(struct device *dev, size_t size, if (page) { trace_dma_alloc_pages(dev, page_to_virt(page), *dma_handle, size, dir, gfp, 0); - debug_dma_map_page(dev, page, 0, size, dir, *dma_handle, 0); + debug_dma_alloc_pages(dev, page, size, dir, *dma_handle, 0); } else { trace_dma_alloc_pages(dev, NULL, 0, size, dir, gfp, 0); } @@ -738,7 +738,7 @@ void dma_free_pages(struct device *dev, size_t size, struct page *page, dma_addr_t dma_handle, enum dma_data_direction dir) { trace_dma_free_pages(dev, page_to_virt(page), dma_handle, size, dir, 0); - debug_dma_unmap_page(dev, dma_handle, size, dir); + debug_dma_free_pages(dev, page, size, dir, dma_handle); __dma_free_pages(dev, size, page, dma_handle, dir); } EXPORT_SYMBOL_GPL(dma_free_pages); -- cgit v1.2.3 From 81ac63321eb936b1a1f7045b37674661f8ffb4a5 Mon Sep 17 00:00:00 2001 From: Qianfeng Rong Date: Tue, 5 Aug 2025 10:36:29 +0800 Subject: trace: Remove redundant __GFP_NOWARN Commit 16f5dfbc851b ("gfp: include __GFP_NOWARN in GFP_NOWAIT") made GFP_NOWAIT implicitly include __GFP_NOWARN. Therefore, explicit __GFP_NOWARN combined with GFP_NOWAIT (e.g., `GFP_NOWAIT | __GFP_NOWARN`) is now redundant. Let's clean up these redundant flags across subsystems. No functional changes. Cc: Masami Hiramatsu Cc: Mathieu Desnoyers Link: https://lore.kernel.org/20250805023630.335719-1-rongqianfeng@vivo.com Signed-off-by: Qianfeng Rong Signed-off-by: Steven Rostedt (Google) --- kernel/trace/trace_events_user.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel') diff --git a/kernel/trace/trace_events_user.c b/kernel/trace/trace_events_user.c index af42aaa3d172..2ab283fd3032 100644 --- a/kernel/trace/trace_events_user.c +++ b/kernel/trace/trace_events_user.c @@ -496,7 +496,7 @@ static bool user_event_enabler_queue_fault(struct user_event_mm *mm, { struct user_event_enabler_fault *fault; - fault = kmem_cache_zalloc(fault_cache, GFP_NOWAIT | __GFP_NOWARN); + fault = kmem_cache_zalloc(fault_cache, GFP_NOWAIT); if (!fault) return false; -- cgit v1.2.3 From 3d62ab32df065e4a7797204a918f6489ddb8a237 Mon Sep 17 00:00:00 2001 From: Luo Gengkun Date: Tue, 19 Aug 2025 10:51:52 +0000 Subject: tracing: Fix tracing_marker may trigger page fault during preempt_disable Both tracing_mark_write and tracing_mark_raw_write call __copy_from_user_inatomic during preempt_disable. But in some case, __copy_from_user_inatomic may trigger page fault, and will call schedule() subtly. And if a task is migrated to other cpu, the following warning will be trigger: if (RB_WARN_ON(cpu_buffer, !local_read(&cpu_buffer->committing))) An example can illustrate this issue: process flow CPU --------------------------------------------------------------------- tracing_mark_raw_write(): cpu:0 ... ring_buffer_lock_reserve(): cpu:0 ... cpu = raw_smp_processor_id() cpu:0 cpu_buffer = buffer->buffers[cpu] cpu:0 ... ... __copy_from_user_inatomic(): cpu:0 ... # page fault do_mem_abort(): cpu:0 ... # Call schedule schedule() cpu:0 ... # the task schedule to cpu1 __buffer_unlock_commit(): cpu:1 ... ring_buffer_unlock_commit(): cpu:1 ... cpu = raw_smp_processor_id() cpu:1 cpu_buffer = buffer->buffers[cpu] cpu:1 As shown above, the process will acquire cpuid twice and the return values are not the same. To fix this problem using copy_from_user_nofault instead of __copy_from_user_inatomic, as the former performs 'access_ok' before copying. Link: https://lore.kernel.org/20250819105152.2766363-1-luogengkun@huaweicloud.com Fixes: 656c7f0d2d2b ("tracing: Replace kmap with copy_from_user() in trace_marker writing") Signed-off-by: Luo Gengkun Reviewed-by: Masami Hiramatsu (Google) Signed-off-by: Steven Rostedt (Google) --- kernel/trace/trace.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'kernel') diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 1b7db732c0b1..2f1ae6c0ee81 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -7209,7 +7209,7 @@ static ssize_t write_marker_to_buffer(struct trace_array *tr, const char __user entry = ring_buffer_event_data(event); entry->ip = ip; - len = __copy_from_user_inatomic(&entry->buf, ubuf, cnt); + len = copy_from_user_nofault(&entry->buf, ubuf, cnt); if (len) { memcpy(&entry->buf, FAULTED_STR, FAULTED_SIZE); cnt = FAULTED_SIZE; @@ -7306,7 +7306,7 @@ static ssize_t write_raw_marker_to_buffer(struct trace_array *tr, entry = ring_buffer_event_data(event); - len = __copy_from_user_inatomic(&entry->id, ubuf, cnt); + len = copy_from_user_nofault(&entry->id, ubuf, cnt); if (len) { entry->id = -1; memcpy(&entry->buf, FAULTED_STR, FAULTED_SIZE); -- cgit v1.2.3 From 18dbcbfabfffc4a5d3ea10290c5ad27f22b0d240 Mon Sep 17 00:00:00 2001 From: Kan Liang Date: Mon, 11 Aug 2025 11:26:44 -0700 Subject: perf: Fix the POLL_HUP delivery breakage The event_limit can be set by the PERF_EVENT_IOC_REFRESH to limit the number of events. When the event_limit reaches 0, the POLL_HUP signal should be sent. But it's missed. The corresponding counter should be stopped when the event_limit reaches 0. It was implemented in the ARCH-specific code. However, since the commit 9734e25fbf5a ("perf: Fix the throttle logic for a group"), all the ARCH-specific code has been moved to the generic code. The code to handle the event_limit was lost. Add the event->pmu->stop(event, 0); back. Fixes: 9734e25fbf5a ("perf: Fix the throttle logic for a group") Closes: https://lore.kernel.org/lkml/aICYAqM5EQUlTqtX@li-2b55cdcc-350b-11b2-a85c-a78bff51fc11.ibm.com/ Reported-by: Sumanth Korikkar Signed-off-by: Kan Liang Signed-off-by: Peter Zijlstra (Intel) Tested-by: Sumanth Korikkar Link: https://lkml.kernel.org/r/20250811182644.1305952-1-kan.liang@linux.intel.com --- kernel/events/core.c | 1 + 1 file changed, 1 insertion(+) (limited to 'kernel') diff --git a/kernel/events/core.c b/kernel/events/core.c index 872122e074e5..820127536e62 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -10330,6 +10330,7 @@ static int __perf_event_overflow(struct perf_event *event, ret = 1; event->pending_kill = POLL_HUP; perf_event_disable_inatomic(event); + event->pmu->stop(event, 0); } if (event->attr.sigtrap) { -- cgit v1.2.3 From 762af5a2aa0ad18da1316666dae30d369268d44c Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Thomas=20Wei=C3=9Fschuh?= Date: Mon, 25 Aug 2025 15:26:35 +0200 Subject: vdso/vsyscall: Avoid slow division loop in auxiliary clock update MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The call to __iter_div_u64_rem() in vdso_time_update_aux() is a wrapper around subtraction. It cannot be used to divide large numbers, as that introduces long, computationally expensive delays. A regular u64 division is also not possible in the timekeeper update path as it can be too slow. Instead of splitting the ktime_t offset into into second and subsecond components during the timekeeper update fast-path, do it together with the adjustment of tk->offs_aux in the slow-path. Equivalent to the handling of offs_boot and monotonic_to_boot. Reuse the storage of monotonic_to_boot for the new field, as it is not used by auxiliary timekeepers. Fixes: 380b84e168e5 ("vdso/vsyscall: Update auxiliary clock data in the datapage") Reported-by: Miroslav Lichvar Signed-off-by: Thomas Weißschuh Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/all/20250825-vdso-auxclock-division-v1-1-a1d32a16a313@linutronix.de Closes: https://lore.kernel.org/lkml/aKwsNNWsHJg8IKzj@localhost/ --- kernel/time/timekeeping.c | 10 ++++++++-- kernel/time/vsyscall.c | 4 ++-- 2 files changed, 10 insertions(+), 4 deletions(-) (limited to 'kernel') diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 059fa8b79be6..b6974fce800c 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -83,6 +83,12 @@ static inline bool tk_is_aux(const struct timekeeper *tk) } #endif +static inline void tk_update_aux_offs(struct timekeeper *tk, ktime_t offs) +{ + tk->offs_aux = offs; + tk->monotonic_to_aux = ktime_to_timespec64(offs); +} + /* flag for if timekeeping is suspended */ int __read_mostly timekeeping_suspended; @@ -1506,7 +1512,7 @@ static int __timekeeping_inject_offset(struct tk_data *tkd, const struct timespe timekeeping_restore_shadow(tkd); return -EINVAL; } - tks->offs_aux = offs; + tk_update_aux_offs(tks, offs); } timekeeping_update_from_shadow(tkd, TK_UPDATE_ALL); @@ -2937,7 +2943,7 @@ static int aux_clock_set(const clockid_t id, const struct timespec64 *tnew) * xtime ("realtime") is not applicable for auxiliary clocks and * kept in sync with "monotonic". */ - aux_tks->offs_aux = ktime_sub(timespec64_to_ktime(*tnew), tnow); + tk_update_aux_offs(aux_tks, ktime_sub(timespec64_to_ktime(*tnew), tnow)); timekeeping_update_from_shadow(aux_tkd, TK_UPDATE_ALL); return 0; diff --git a/kernel/time/vsyscall.c b/kernel/time/vsyscall.c index 8ba8b0d8a387..aa59919b8f2c 100644 --- a/kernel/time/vsyscall.c +++ b/kernel/time/vsyscall.c @@ -159,10 +159,10 @@ void vdso_time_update_aux(struct timekeeper *tk) if (clock_mode != VDSO_CLOCKMODE_NONE) { fill_clock_configuration(vc, &tk->tkr_mono); - vdso_ts->sec = tk->xtime_sec; + vdso_ts->sec = tk->xtime_sec + tk->monotonic_to_aux.tv_sec; nsec = tk->tkr_mono.xtime_nsec >> tk->tkr_mono.shift; - nsec += tk->offs_aux; + nsec += tk->monotonic_to_aux.tv_nsec; vdso_ts->sec += __iter_div_u64_rem(nsec, NSEC_PER_SEC, &nsec); nsec = nsec << tk->tkr_mono.shift; vdso_ts->nsec = nsec; -- cgit v1.2.3 From 5ebf512f335053a42482ebff91e46c6dc156bf8c Mon Sep 17 00:00:00 2001 From: Christian Loehle Date: Wed, 3 Sep 2025 16:48:32 +0100 Subject: sched: Fix sched_numa_find_nth_cpu() if mask offline sched_numa_find_nth_cpu() uses a bsearch to look for the 'closest' CPU in sched_domains_numa_masks and given cpus mask. However they might not intersect if all CPUs in the cpus mask are offline. bsearch will return NULL in that case, bail out instead of dereferencing a bogus pointer. The previous behaviour lead to this bug when using maxcpus=4 on an rk3399 (LLLLbb) (i.e. booting with all big CPUs offline): [ 1.422922] Unable to handle kernel paging request at virtual address ffffff8000000000 [ 1.423635] Mem abort info: [ 1.423889] ESR = 0x0000000096000006 [ 1.424227] EC = 0x25: DABT (current EL), IL = 32 bits [ 1.424715] SET = 0, FnV = 0 [ 1.424995] EA = 0, S1PTW = 0 [ 1.425279] FSC = 0x06: level 2 translation fault [ 1.425735] Data abort info: [ 1.425998] ISV = 0, ISS = 0x00000006, ISS2 = 0x00000000 [ 1.426499] CM = 0, WnR = 0, TnD = 0, TagAccess = 0 [ 1.426952] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 [ 1.427428] swapper pgtable: 4k pages, 39-bit VAs, pgdp=0000000004a9f000 [ 1.428038] [ffffff8000000000] pgd=18000000f7fff403, p4d=18000000f7fff403, pud=18000000f7fff403, pmd=0000000000000000 [ 1.429014] Internal error: Oops: 0000000096000006 [#1] SMP [ 1.429525] Modules linked in: [ 1.429813] CPU: 3 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.17.0-rc4-dirty #343 PREEMPT [ 1.430559] Hardware name: Pine64 RockPro64 v2.1 (DT) [ 1.431012] pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 1.431634] pc : sched_numa_find_nth_cpu+0x2a0/0x488 [ 1.432094] lr : sched_numa_find_nth_cpu+0x284/0x488 [ 1.432543] sp : ffffffc084e1b960 [ 1.432843] x29: ffffffc084e1b960 x28: ffffff80078a8800 x27: ffffffc0846eb1d0 [ 1.433495] x26: 0000000000000000 x25: 0000000000000000 x24: 0000000000000000 [ 1.434144] x23: 0000000000000000 x22: fffffffffff7f093 x21: ffffffc081de6378 [ 1.434792] x20: 0000000000000000 x19: 0000000ffff7f093 x18: 00000000ffffffff [ 1.435441] x17: 3030303866666666 x16: 66663d736b73616d x15: ffffffc104e1b5b7 [ 1.436091] x14: 0000000000000000 x13: ffffffc084712860 x12: 0000000000000372 [ 1.436739] x11: 0000000000000126 x10: ffffffc08476a860 x9 : ffffffc084712860 [ 1.437389] x8 : 00000000ffffefff x7 : ffffffc08476a860 x6 : 0000000000000000 [ 1.438036] x5 : 000000000000bff4 x4 : 0000000000000000 x3 : 0000000000000000 [ 1.438683] x2 : 0000000000000000 x1 : ffffffc0846eb000 x0 : ffffff8000407b68 [ 1.439332] Call trace: [ 1.439559] sched_numa_find_nth_cpu+0x2a0/0x488 (P) [ 1.440016] smp_call_function_any+0xc8/0xd0 [ 1.440416] armv8_pmu_init+0x58/0x27c [ 1.440770] armv8_cortex_a72_pmu_init+0x20/0x2c [ 1.441199] arm_pmu_device_probe+0x1e4/0x5e8 [ 1.441603] armv8_pmu_device_probe+0x1c/0x28 [ 1.442007] platform_probe+0x5c/0xac [ 1.442347] really_probe+0xbc/0x298 [ 1.442683] __driver_probe_device+0x78/0x12c [ 1.443087] driver_probe_device+0xdc/0x160 [ 1.443475] __driver_attach+0x94/0x19c [ 1.443833] bus_for_each_dev+0x74/0xd4 [ 1.444190] driver_attach+0x24/0x30 [ 1.444525] bus_add_driver+0xe4/0x208 [ 1.444874] driver_register+0x60/0x128 [ 1.445233] __platform_driver_register+0x24/0x30 [ 1.445662] armv8_pmu_driver_init+0x28/0x4c [ 1.446059] do_one_initcall+0x44/0x25c [ 1.446416] kernel_init_freeable+0x1dc/0x3bc [ 1.446820] kernel_init+0x20/0x1d8 [ 1.447151] ret_from_fork+0x10/0x20 [ 1.447493] Code: 90022e21 f000e5f5 910de2b5 2a1703e2 (f8767803) [ 1.448040] ---[ end trace 0000000000000000 ]--- [ 1.448483] note: swapper/0[1] exited with preempt_count 1 [ 1.449047] Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b [ 1.449741] SMP: stopping secondary CPUs [ 1.450105] Kernel Offset: disabled [ 1.450419] CPU features: 0x000000,00080000,20002001,0400421b [ 1.450935] Memory Limit: none [ 1.451217] ---[ end Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b ]--- Yury: with the fix, the function returns cpu == nr_cpu_ids, and later in smp_call_function_any -> smp_call_function_single -> generic_exec_single we test the cpu for '>= nr_cpu_ids' and return -ENXIO. So everything is handled correctly. Fixes: cd7f55359c90 ("sched: add sched_numa_find_nth_cpu()") Cc: stable@vger.kernel.org Signed-off-by: Christian Loehle Signed-off-by: Yury Norov (NVIDIA) --- kernel/sched/topology.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'kernel') diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c index 977e133bb8a4..6e2f54169e66 100644 --- a/kernel/sched/topology.c +++ b/kernel/sched/topology.c @@ -2201,6 +2201,8 @@ int sched_numa_find_nth_cpu(const struct cpumask *cpus, int cpu, int node) goto unlock; hop_masks = bsearch(&k, k.masks, sched_domains_numa_levels, sizeof(k.masks[0]), hop_cmp); + if (!hop_masks) + goto unlock; hop = hop_masks - k.masks; ret = hop ? -- cgit v1.2.3 From 4540f1d23e7f387880ce46d11b5cd3f27248bf8d Mon Sep 17 00:00:00 2001 From: Stanislav Fort Date: Tue, 2 Sep 2025 14:00:49 +0300 Subject: audit: fix out-of-bounds read in audit_compare_dname_path() When a watch on dir=/ is combined with an fsnotify event for a single-character name directly under / (e.g., creating /a), an out-of-bounds read can occur in audit_compare_dname_path(). The helper parent_len() returns 1 for "/". In audit_compare_dname_path(), when parentlen equals the full path length (1), the code sets p = path + 1 and pathlen = 1 - 1 = 0. The subsequent loop then dereferences p[pathlen - 1] (i.e., p[-1]), causing an out-of-bounds read. Fix this by adding a pathlen > 0 check to the while loop condition to prevent the out-of-bounds access. Cc: stable@vger.kernel.org Fixes: e92eebb0d611 ("audit: fix suffixed '/' filename matching") Reported-by: Stanislav Fort Suggested-by: Linus Torvalds Signed-off-by: Stanislav Fort [PM: subject tweak, sign-off email fixes] Signed-off-by: Paul Moore --- kernel/auditfilter.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel') diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c index e3f42018ed46..f7708fe2c457 100644 --- a/kernel/auditfilter.c +++ b/kernel/auditfilter.c @@ -1326,7 +1326,7 @@ int audit_compare_dname_path(const struct qstr *dname, const char *path, int par /* handle trailing slashes */ pathlen -= parentlen; - while (p[pathlen - 1] == '/') + while (pathlen > 0 && p[pathlen - 1] == '/') pathlen--; if (pathlen != dlen) -- cgit v1.2.3 From ab1396af7595e7d49a3850481b24d7fe7cbdfd31 Mon Sep 17 00:00:00 2001 From: Guenter Roeck Date: Fri, 5 Sep 2025 22:06:18 -0700 Subject: trace/fgraph: Fix error handling Commit edede7a6dcd7 ("trace/fgraph: Fix the warning caused by missing unregister notifier") added a call to unregister the PM notifier if register_ftrace_graph() failed. It does so unconditionally. However, the PM notifier is only registered with the first call to register_ftrace_graph(). If the first registration was successful and a subsequent registration failed, the notifier is now unregistered even if ftrace graphs are still registered. Fix the problem by only unregistering the PM notifier during error handling if there are no active fgraph registrations. Fixes: edede7a6dcd7 ("trace/fgraph: Fix the warning caused by missing unregister notifier") Closes: https://lore.kernel.org/all/63b0ba5a-a928-438e-84f9-93028dd72e54@roeck-us.net/ Cc: Ye Weihua Cc: Masami Hiramatsu Cc: Mark Rutland Cc: Mathieu Desnoyers Link: https://lore.kernel.org/20250906050618.2634078-1-linux@roeck-us.net Signed-off-by: Guenter Roeck Signed-off-by: Steven Rostedt (Google) --- kernel/trace/fgraph.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'kernel') diff --git a/kernel/trace/fgraph.c b/kernel/trace/fgraph.c index 2a42c1036ea8..1e3b32b1e82c 100644 --- a/kernel/trace/fgraph.c +++ b/kernel/trace/fgraph.c @@ -1397,7 +1397,8 @@ error: ftrace_graph_active--; gops->saved_func = NULL; fgraph_lru_release_index(i); - unregister_pm_notifier(&ftrace_suspend_notifier); + if (!ftrace_graph_active) + unregister_pm_notifier(&ftrace_suspend_notifier); } return ret; } -- cgit v1.2.3 From c1628c00c4351dd0727ef7f670694f68d9e663d8 Mon Sep 17 00:00:00 2001 From: Wang Liang Date: Sat, 6 Sep 2025 11:56:10 +0800 Subject: tracing/osnoise: Fix null-ptr-deref in bitmap_parselist() A crash was observed with the following output: BUG: kernel NULL pointer dereference, address: 0000000000000010 Oops: Oops: 0000 [#1] SMP NOPTI CPU: 2 UID: 0 PID: 92 Comm: osnoise_cpus Not tainted 6.17.0-rc4-00201-gd69eb204c255 #138 PREEMPT(voluntary) RIP: 0010:bitmap_parselist+0x53/0x3e0 Call Trace: osnoise_cpus_write+0x7a/0x190 vfs_write+0xf8/0x410 ? do_sys_openat2+0x88/0xd0 ksys_write+0x60/0xd0 do_syscall_64+0xa4/0x260 entry_SYSCALL_64_after_hwframe+0x77/0x7f This issue can be reproduced by below code: fd=open("/sys/kernel/debug/tracing/osnoise/cpus", O_WRONLY); write(fd, "0-2", 0); When user pass 'count=0' to osnoise_cpus_write(), kmalloc() will return ZERO_SIZE_PTR (16) and cpulist_parse() treat it as a normal value, which trigger the null pointer dereference. Add check for the parameter 'count'. Cc: Cc: Cc: Link: https://lore.kernel.org/20250906035610.3880282-1-wangliang74@huawei.com Fixes: 17f89102fe23 ("tracing/osnoise: Allow arbitrarily long CPU string") Signed-off-by: Wang Liang Signed-off-by: Steven Rostedt (Google) --- kernel/trace/trace_osnoise.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'kernel') diff --git a/kernel/trace/trace_osnoise.c b/kernel/trace/trace_osnoise.c index fd259da0aa64..337bc0eb5d71 100644 --- a/kernel/trace/trace_osnoise.c +++ b/kernel/trace/trace_osnoise.c @@ -2322,6 +2322,9 @@ osnoise_cpus_write(struct file *filp, const char __user *ubuf, size_t count, int running, err; char *buf __free(kfree) = NULL; + if (count < 1) + return 0; + buf = kmalloc(count, GFP_KERNEL); if (!buf) return -ENOMEM; -- cgit v1.2.3 From cd4453c5e983cf1fd5757e9acb915adb1e4602b6 Mon Sep 17 00:00:00 2001 From: Pu Lehui Date: Mon, 8 Sep 2025 02:46:58 +0000 Subject: tracing: Silence warning when chunk allocation fails in trace_pid_write Syzkaller trigger a fault injection warning: WARNING: CPU: 1 PID: 12326 at tracepoint_add_func+0xbfc/0xeb0 Modules linked in: CPU: 1 UID: 0 PID: 12326 Comm: syz.6.10325 Tainted: G U 6.14.0-rc5-syzkaller #0 Tainted: [U]=USER Hardware name: Google Compute Engine/Google Compute Engine RIP: 0010:tracepoint_add_func+0xbfc/0xeb0 kernel/tracepoint.c:294 Code: 09 fe ff 90 0f 0b 90 0f b6 74 24 43 31 ff 41 bc ea ff ff ff RSP: 0018:ffffc9000414fb48 EFLAGS: 00010283 RAX: 00000000000012a1 RBX: ffffffff8e240ae0 RCX: ffffc90014b78000 RDX: 0000000000080000 RSI: ffffffff81bbd78b RDI: 0000000000000001 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: ffffffffffffffef R13: 0000000000000000 R14: dffffc0000000000 R15: ffffffff81c264f0 FS: 00007f27217f66c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2e80dff8 CR3: 00000000268f8000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: tracepoint_probe_register_prio+0xc0/0x110 kernel/tracepoint.c:464 register_trace_prio_sched_switch include/trace/events/sched.h:222 [inline] register_pid_events kernel/trace/trace_events.c:2354 [inline] event_pid_write.isra.0+0x439/0x7a0 kernel/trace/trace_events.c:2425 vfs_write+0x24c/0x1150 fs/read_write.c:677 ksys_write+0x12b/0x250 fs/read_write.c:731 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f We can reproduce the warning by following the steps below: 1. echo 8 >> set_event_notrace_pid. Let tr->filtered_pids owns one pid and register sched_switch tracepoint. 2. echo ' ' >> set_event_pid, and perform fault injection during chunk allocation of trace_pid_list_alloc. Let pid_list with no pid and assign to tr->filtered_pids. 3. echo ' ' >> set_event_pid. Let pid_list is NULL and assign to tr->filtered_pids. 4. echo 9 >> set_event_pid, will trigger the double register sched_switch tracepoint warning. The reason is that syzkaller injects a fault into the chunk allocation in trace_pid_list_alloc, causing a failure in trace_pid_list_set, which may trigger double register of the same tracepoint. This only occurs when the system is about to crash, but to suppress this warning, let's add failure handling logic to trace_pid_list_set. Link: https://lore.kernel.org/20250908024658.2390398-1-pulehui@huaweicloud.com Fixes: 8d6e90983ade ("tracing: Create a sparse bitmask for pid filtering") Reported-by: syzbot+161412ccaeff20ce4dde@syzkaller.appspotmail.com Closes: https://lore.kernel.org/all/67cb890e.050a0220.d8275.022e.GAE@google.com Signed-off-by: Pu Lehui Signed-off-by: Steven Rostedt (Google) --- kernel/trace/trace.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'kernel') diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 2f1ae6c0ee81..b3c94fbaf002 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -834,7 +834,10 @@ int trace_pid_write(struct trace_pid_list *filtered_pids, /* copy the current bits to the new max */ ret = trace_pid_list_first(filtered_pids, &pid); while (!ret) { - trace_pid_list_set(pid_list, pid); + ret = trace_pid_list_set(pid_list, pid); + if (ret < 0) + goto out; + ret = trace_pid_list_next(filtered_pids, pid + 1, &pid); nr_pids++; } @@ -871,6 +874,7 @@ int trace_pid_write(struct trace_pid_list *filtered_pids, trace_parser_clear(&parser); ret = 0; } + out: trace_parser_put(&parser); if (ret < 0) { -- cgit v1.2.3 From e895f8e29119c8c966ea794af9e9100b10becb88 Mon Sep 17 00:00:00 2001 From: Xiongfeng Wang Date: Tue, 5 Aug 2025 16:10:25 +0800 Subject: hrtimers: Unconditionally update target CPU base after offline timer migration When testing softirq based hrtimers on an ARM32 board, with high resolution mode and NOHZ inactive, softirq based hrtimers fail to expire after being moved away from an offline CPU: CPU0 CPU1 hrtimer_start(..., HRTIMER_MODE_SOFT); cpu_down(CPU1) ... hrtimers_cpu_dying() // Migrate timers to CPU0 smp_call_function_single(CPU0, returgger_next_event); retrigger_next_event() if (!highres && !nohz) return; As retrigger_next_event() is a NOOP when both high resolution timers and NOHZ are inactive CPU0's hrtimer_cpu_base::softirq_expires_next is not updated and the migrated softirq timers never expire unless there is a softirq based hrtimer queued on CPU0 later. Fix this by removing the hrtimer_hres_active() and tick_nohz_active() check in retrigger_next_event(), which enforces a full update of the CPU base. As this is not a fast path the extra cost does not matter. [ tglx: Massaged change log ] Fixes: 5c0930ccaad5 ("hrtimers: Push pending hrtimers away from outgoing CPU earlier") Co-developed-by: Frederic Weisbecker Signed-off-by: Frederic Weisbecker Signed-off-by: Xiongfeng Wang Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/all/20250805081025.54235-1-wangxiongfeng2@huawei.com --- kernel/time/hrtimer.c | 11 +++-------- 1 file changed, 3 insertions(+), 8 deletions(-) (limited to 'kernel') diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c index 30899a8cc52c..e8c479329282 100644 --- a/kernel/time/hrtimer.c +++ b/kernel/time/hrtimer.c @@ -787,10 +787,10 @@ static void retrigger_next_event(void *arg) * of the next expiring timer is enough. The return from the SMP * function call will take care of the reprogramming in case the * CPU was in a NOHZ idle sleep. + * + * In periodic low resolution mode, the next softirq expiration + * must also be updated. */ - if (!hrtimer_hres_active(base) && !tick_nohz_active) - return; - raw_spin_lock(&base->lock); hrtimer_update_base(base); if (hrtimer_hres_active(base)) @@ -2295,11 +2295,6 @@ int hrtimers_cpu_dying(unsigned int dying_cpu) &new_base->clock_base[i]); } - /* - * The migration might have changed the first expiring softirq - * timer on this CPU. Update it. - */ - __hrtimer_get_next_event(new_base, HRTIMER_ACTIVE_SOFT); /* Tell the other CPU to retrigger the next event */ smp_call_function_single(ncpu, retrigger_next_event, NULL, 0); -- cgit v1.2.3 From f9bb6ffa7f5ad0f8ee0f53fc4a10655872ee4a14 Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Fri, 29 Aug 2025 16:36:56 +0200 Subject: bpf: Fix out-of-bounds dynptr write in bpf_crypto_crypt Stanislav reported that in bpf_crypto_crypt() the destination dynptr's size is not validated to be at least as large as the source dynptr's size before calling into the crypto backend with 'len = src_len'. This can result in an OOB write when the destination is smaller than the source. Concretely, in mentioned function, psrc and pdst are both linear buffers fetched from each dynptr: psrc = __bpf_dynptr_data(src, src_len); [...] pdst = __bpf_dynptr_data_rw(dst, dst_len); [...] err = decrypt ? ctx->type->decrypt(ctx->tfm, psrc, pdst, src_len, piv) : ctx->type->encrypt(ctx->tfm, psrc, pdst, src_len, piv); The crypto backend expects pdst to be large enough with a src_len length that can be written. Add an additional src_len > dst_len check and bail out if it's the case. Note that these kfuncs are accessible under root privileges only. Fixes: 3e1c6f35409f ("bpf: make common crypto API for TC/XDP programs") Reported-by: Stanislav Fort Signed-off-by: Daniel Borkmann Cc: Vadim Fedorenko Reviewed-by: Vadim Fedorenko Link: https://lore.kernel.org/r/20250829143657.318524-1-daniel@iogearbox.net Signed-off-by: Alexei Starovoitov --- kernel/bpf/crypto.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel') diff --git a/kernel/bpf/crypto.c b/kernel/bpf/crypto.c index 94854cd9c4cc..83c4d9943084 100644 --- a/kernel/bpf/crypto.c +++ b/kernel/bpf/crypto.c @@ -278,7 +278,7 @@ static int bpf_crypto_crypt(const struct bpf_crypto_ctx *ctx, siv_len = siv ? __bpf_dynptr_size(siv) : 0; src_len = __bpf_dynptr_size(src); dst_len = __bpf_dynptr_size(dst); - if (!src_len || !dst_len) + if (!src_len || !dst_len || src_len > dst_len) return -EINVAL; if (siv_len != ctx->siv_len) -- cgit v1.2.3 From 7edfc024708258d75f65fadffd7e5f6ac46810b6 Mon Sep 17 00:00:00 2001 From: Rong Tao Date: Sat, 30 Aug 2025 00:31:58 +0800 Subject: bpf: Fix bpf_strnstr() to handle suffix match cases better bpf_strnstr() should not treat the ending '\0' of s2 as a matching character if the parameter 'len' equal to s2 string length, for example: 1. bpf_strnstr("openat", "open", 4) = -ENOENT 2. bpf_strnstr("openat", "open", 5) = 0 This patch makes (1) return 0, fix just the `len == strlen(s2)` case. And fix a more general case when s2 is a suffix of the first len characters of s1. Fixes: e91370550f1f ("bpf: Add kfuncs for read-only string operations") Signed-off-by: Rong Tao Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/tencent_17DC57B9D16BC443837021BEACE84B7C1507@qq.com Signed-off-by: Alexei Starovoitov --- kernel/bpf/helpers.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) (limited to 'kernel') diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c index 6b4877e85a68..b9b0c5fe33f6 100644 --- a/kernel/bpf/helpers.c +++ b/kernel/bpf/helpers.c @@ -3664,10 +3664,17 @@ __bpf_kfunc int bpf_strnstr(const char *s1__ign, const char *s2__ign, size_t len guard(pagefault)(); for (i = 0; i < XATTR_SIZE_MAX; i++) { - for (j = 0; i + j < len && j < XATTR_SIZE_MAX; j++) { + for (j = 0; i + j <= len && j < XATTR_SIZE_MAX; j++) { __get_kernel_nofault(&c2, s2__ign + j, char, err_out); if (c2 == '\0') return i; + /* + * We allow reading an extra byte from s2 (note the + * `i + j <= len` above) to cover the case when s2 is + * a suffix of the first len chars of s1. + */ + if (i + j == len) + break; __get_kernel_nofault(&c1, s1__ign + j, char, err_out); if (c1 == '\0') return -ENOENT; -- cgit v1.2.3 From 0d80e7f951be1bdd08d328fd87694be0d6e8aaa8 Mon Sep 17 00:00:00 2001 From: Kumar Kartikeya Dwivedi Date: Tue, 9 Sep 2025 18:49:59 +0000 Subject: rqspinlock: Choose trylock fallback for NMI waiters Currently, out of all 3 types of waiters in the rqspinlock slow path (i.e., pending bit waiter, wait queue head waiter, and wait queue non-head waiter), only the pending bit waiter and wait queue head waiters apply deadlock checks and a timeout on their waiting loop. The assumption here was that the wait queue head's forward progress would be sufficient to identify cases where the lock owner or pending bit waiter is stuck, and non-head waiters relying on the head waiter would prove to be sufficient for their own forward progress. However, the head waiter itself can be preempted by a non-head waiter for the same lock (AA) or a different lock (ABBA) in a manner that impedes its forward progress. In such a case, non-head waiters not performing deadlock and timeout checks becomes insufficient, and the system can enter a state of lockup. This is typically not a concern with non-NMI lock acquisitions, as lock holders which in run in different contexts (IRQ, non-IRQ) use "irqsave" variants of the lock APIs, which naturally excludes such lock holders from preempting one another on the same CPU. It might seem likely that a similar case may occur for rqspinlock when programs are attached to contention tracepoints (begin, end), however, these tracepoints either precede the enqueue into the wait queue, or succeed it, therefore cannot be used to preempt a head waiter's waiting loop. We must still be careful against nested kprobe and fentry programs that may attach to the middle of the head's waiting loop to stall forward progress and invoke another rqspinlock acquisition that proceeds as a non-head waiter. To this end, drop CC_FLAGS_FTRACE from the rqspinlock.o object file. For now, this issue is resolved by falling back to a repeated trylock on the lock word from NMI context, while performing the deadlock checks to break out early in case forward progress is impossible, and use the timeout as a final fallback. A more involved fix to terminate the queue when such a condition occurs will be made as a follow up. A selftest to stress this aspect of nested NMI/non-NMI locking attempts will be added in a subsequent patch to the bpf-next tree when this fix lands and trees are synchronized. Reported-by: Josef Bacik Fixes: 164c246571e9 ("rqspinlock: Protect waiters in queue from stalls") Signed-off-by: Kumar Kartikeya Dwivedi Link: https://lore.kernel.org/r/20250909184959.3509085-1-memxor@gmail.com Signed-off-by: Alexei Starovoitov --- kernel/bpf/Makefile | 1 + kernel/bpf/rqspinlock.c | 2 +- 2 files changed, 2 insertions(+), 1 deletion(-) (limited to 'kernel') diff --git a/kernel/bpf/Makefile b/kernel/bpf/Makefile index 269c04a24664..f6cf8c2af5f7 100644 --- a/kernel/bpf/Makefile +++ b/kernel/bpf/Makefile @@ -62,3 +62,4 @@ CFLAGS_REMOVE_bpf_lru_list.o = $(CC_FLAGS_FTRACE) CFLAGS_REMOVE_queue_stack_maps.o = $(CC_FLAGS_FTRACE) CFLAGS_REMOVE_lpm_trie.o = $(CC_FLAGS_FTRACE) CFLAGS_REMOVE_ringbuf.o = $(CC_FLAGS_FTRACE) +CFLAGS_REMOVE_rqspinlock.o = $(CC_FLAGS_FTRACE) diff --git a/kernel/bpf/rqspinlock.c b/kernel/bpf/rqspinlock.c index 5ab354d55d82..a00561b1d3e5 100644 --- a/kernel/bpf/rqspinlock.c +++ b/kernel/bpf/rqspinlock.c @@ -471,7 +471,7 @@ queue: * any MCS node. This is not the most elegant solution, but is * simple enough. */ - if (unlikely(idx >= _Q_MAX_NODES)) { + if (unlikely(idx >= _Q_MAX_NODES || in_nmi())) { lockevent_inc(lock_no_node); RES_RESET_TIMEOUT(ts, RES_DEF_TIMEOUT); while (!queued_spin_trylock(lock)) { -- cgit v1.2.3 From df0cb5cb50bd54d3cd4d0d83417ceec6a66404aa Mon Sep 17 00:00:00 2001 From: KaFai Wan Date: Tue, 9 Sep 2025 22:46:14 +0800 Subject: bpf: Allow fall back to interpreter for programs with stack size <= 512 OpenWRT users reported regression on ARMv6 devices after updating to latest HEAD, where tcpdump filter: tcpdump "not ether host 3c37121a2b3c and not ether host 184ecbca2a3a \ and not ether host 14130b4d3f47 and not ether host f0f61cf440b7 \ and not ether host a84b4dedf471 and not ether host d022be17e1d7 \ and not ether host 5c497967208b and not ether host 706655784d5b" fails with warning: "Kernel filter failed: No error information" when using config: # CONFIG_BPF_JIT_ALWAYS_ON is not set CONFIG_BPF_JIT_DEFAULT_ON=y The issue arises because commits: 1. "bpf: Fix array bounds error with may_goto" changed default runtime to __bpf_prog_ret0_warn when jit_requested = 1 2. "bpf: Avoid __bpf_prog_ret0_warn when jit fails" returns error when jit_requested = 1 but jit fails This change restores interpreter fallback capability for BPF programs with stack size <= 512 bytes when jit fails. Reported-by: Felix Fietkau Closes: https://lore.kernel.org/bpf/2e267b4b-0540-45d8-9310-e127bf95fc63@nbd.name/ Fixes: 6ebc5030e0c5 ("bpf: Fix array bounds error with may_goto") Signed-off-by: KaFai Wan Acked-by: Eduard Zingerman Link: https://lore.kernel.org/r/20250909144614.2991253-1-kafai.wan@linux.dev Signed-off-by: Alexei Starovoitov --- kernel/bpf/core.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-) (limited to 'kernel') diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index f8ac77d08ca7..e4568d44e827 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -2366,8 +2366,7 @@ static unsigned int __bpf_prog_ret0_warn(const void *ctx, const struct bpf_insn *insn) { /* If this handler ever gets executed, then BPF_JIT_ALWAYS_ON - * is not working properly, or interpreter is being used when - * prog->jit_requested is not 0, so warn about it! + * is not working properly, so warn about it! */ WARN_ON_ONCE(1); return 0; @@ -2468,8 +2467,9 @@ out: return ret; } -static void bpf_prog_select_func(struct bpf_prog *fp) +static bool bpf_prog_select_interpreter(struct bpf_prog *fp) { + bool select_interpreter = false; #ifndef CONFIG_BPF_JIT_ALWAYS_ON u32 stack_depth = max_t(u32, fp->aux->stack_depth, 1); u32 idx = (round_up(stack_depth, 32) / 32) - 1; @@ -2478,15 +2478,16 @@ static void bpf_prog_select_func(struct bpf_prog *fp) * But for non-JITed programs, we don't need bpf_func, so no bounds * check needed. */ - if (!fp->jit_requested && - !WARN_ON_ONCE(idx >= ARRAY_SIZE(interpreters))) { + if (idx < ARRAY_SIZE(interpreters)) { fp->bpf_func = interpreters[idx]; + select_interpreter = true; } else { fp->bpf_func = __bpf_prog_ret0_warn; } #else fp->bpf_func = __bpf_prog_ret0_warn; #endif + return select_interpreter; } /** @@ -2505,7 +2506,7 @@ struct bpf_prog *bpf_prog_select_runtime(struct bpf_prog *fp, int *err) /* In case of BPF to BPF calls, verifier did all the prep * work with regards to JITing, etc. */ - bool jit_needed = fp->jit_requested; + bool jit_needed = false; if (fp->bpf_func) goto finalize; @@ -2514,7 +2515,8 @@ struct bpf_prog *bpf_prog_select_runtime(struct bpf_prog *fp, int *err) bpf_prog_has_kfunc_call(fp)) jit_needed = true; - bpf_prog_select_func(fp); + if (!bpf_prog_select_interpreter(fp)) + jit_needed = true; /* eBPF JITs can rewrite the program in case constant * blinding is active. However, in case of error during -- cgit v1.2.3 From 6d78b4473cdb08b74662355a9e8510bde09c511e Mon Sep 17 00:00:00 2001 From: Peilin Ye Date: Tue, 9 Sep 2025 09:52:20 +0000 Subject: bpf: Tell memcg to use allow_spinning=false path in bpf_timer_init() Currently, calling bpf_map_kmalloc_node() from __bpf_async_init() can cause various locking issues; see the following stack trace (edited for style) as one example: ... [10.011566] do_raw_spin_lock.cold [10.011570] try_to_wake_up (5) double-acquiring the same [10.011575] kick_pool rq_lock, causing a hardlockup [10.011579] __queue_work [10.011582] queue_work_on [10.011585] kernfs_notify [10.011589] cgroup_file_notify [10.011593] try_charge_memcg (4) memcg accounting raises an [10.011597] obj_cgroup_charge_pages MEMCG_MAX event [10.011599] obj_cgroup_charge_account [10.011600] __memcg_slab_post_alloc_hook [10.011603] __kmalloc_node_noprof ... [10.011611] bpf_map_kmalloc_node [10.011612] __bpf_async_init [10.011615] bpf_timer_init (3) BPF calls bpf_timer_init() [10.011617] bpf_prog_xxxxxxxxxxxxxxxx_fcg_runnable [10.011619] bpf__sched_ext_ops_runnable [10.011620] enqueue_task_scx (2) BPF runs with rq_lock held [10.011622] enqueue_task [10.011626] ttwu_do_activate [10.011629] sched_ttwu_pending (1) grabs rq_lock ... The above was reproduced on bpf-next (b338cf849ec8) by modifying ./tools/sched_ext/scx_flatcg.bpf.c to call bpf_timer_init() during ops.runnable(), and hacking the memcg accounting code a bit to make a bpf_timer_init() call more likely to raise an MEMCG_MAX event. We have also run into other similar variants (both internally and on bpf-next), including double-acquiring cgroup_file_kn_lock, the same worker_pool::lock, etc. As suggested by Shakeel, fix this by using __GFP_HIGH instead of GFP_ATOMIC in __bpf_async_init(), so that e.g. if try_charge_memcg() raises an MEMCG_MAX event, we call __memcg_memory_event() with @allow_spinning=false and avoid calling cgroup_file_notify() there. Depends on mm patch "memcg: skip cgroup_file_notify if spinning is not allowed": https://lore.kernel.org/bpf/20250905201606.66198-1-shakeel.butt@linux.dev/ v0 approach s/bpf_map_kmalloc_node/bpf_mem_alloc/ https://lore.kernel.org/bpf/20250905061919.439648-1-yepeilin@google.com/ v1 approach: https://lore.kernel.org/bpf/20250905234547.862249-1-yepeilin@google.com/ Fixes: b00628b1c7d5 ("bpf: Introduce bpf timers.") Suggested-by: Shakeel Butt Signed-off-by: Peilin Ye Link: https://lore.kernel.org/r/20250909095222.2121438-1-yepeilin@google.com Signed-off-by: Alexei Starovoitov --- kernel/bpf/helpers.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'kernel') diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c index b9b0c5fe33f6..8af62cb243d9 100644 --- a/kernel/bpf/helpers.c +++ b/kernel/bpf/helpers.c @@ -1274,8 +1274,11 @@ static int __bpf_async_init(struct bpf_async_kern *async, struct bpf_map *map, u goto out; } - /* allocate hrtimer via map_kmalloc to use memcg accounting */ - cb = bpf_map_kmalloc_node(map, size, GFP_ATOMIC, map->numa_node); + /* Allocate via bpf_map_kmalloc_node() for memcg accounting. Until + * kmalloc_nolock() is available, avoid locking issues by using + * __GFP_HIGH (GFP_ATOMIC & ~__GFP_RECLAIM). + */ + cb = bpf_map_kmalloc_node(map, size, __GFP_HIGH, map->numa_node); if (!cb) { ret = -ENOMEM; goto out; -- cgit v1.2.3 From e0423541477dfb684fbc6e6b5386054bc650f264 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Fri, 5 Sep 2025 15:44:45 +0200 Subject: PM: EM: Add function for registering a PD without capacity update The intel_pstate driver manages CPU capacity changes itself and it does not need an update of the capacity of all CPUs in the system to be carried out after registering a PD. Moreover, in some configurations (for instance, an SMT-capable hybrid x86 system booted with nosmt in the kernel command line) the em_check_capacity_update() call at the end of em_dev_register_perf_domain() always fails and reschedules itself to run once again in 1 s, so effectively it runs in vain every 1 s forever. To address this, introduce a new variant of em_dev_register_perf_domain(), called em_dev_register_pd_no_update(), that does not invoke em_check_capacity_update(), and make intel_pstate use it instead of the original. Fixes: 7b010f9b9061 ("cpufreq: intel_pstate: EAS support for hybrid platforms") Closes: https://lore.kernel.org/linux-pm/40212796-734c-4140-8a85-854f72b8144d@panix.com/ Reported-by: Kenneth R. Crudup Tested-by: Kenneth R. Crudup Cc: 6.16+ # 6.16+ Signed-off-by: Rafael J. Wysocki --- kernel/power/energy_model.c | 29 +++++++++++++++++++++++++---- 1 file changed, 25 insertions(+), 4 deletions(-) (limited to 'kernel') diff --git a/kernel/power/energy_model.c b/kernel/power/energy_model.c index ea7995a25780..8df55397414a 100644 --- a/kernel/power/energy_model.c +++ b/kernel/power/energy_model.c @@ -552,6 +552,30 @@ EXPORT_SYMBOL_GPL(em_cpu_get); int em_dev_register_perf_domain(struct device *dev, unsigned int nr_states, const struct em_data_callback *cb, const cpumask_t *cpus, bool microwatts) +{ + int ret = em_dev_register_pd_no_update(dev, nr_states, cb, cpus, microwatts); + + if (_is_cpu_device(dev)) + em_check_capacity_update(); + + return ret; +} +EXPORT_SYMBOL_GPL(em_dev_register_perf_domain); + +/** + * em_dev_register_pd_no_update() - Register a perf domain for a device + * @dev : Device to register the PD for + * @nr_states : Number of performance states in the new PD + * @cb : Callback functions for populating the energy model + * @cpus : CPUs to include in the new PD (mandatory if @dev is a CPU device) + * @microwatts : Whether or not the power values in the EM will be in uW + * + * Like em_dev_register_perf_domain(), but does not trigger a CPU capacity + * update after registering the PD, even if @dev is a CPU device. + */ +int em_dev_register_pd_no_update(struct device *dev, unsigned int nr_states, + const struct em_data_callback *cb, + const cpumask_t *cpus, bool microwatts) { struct em_perf_table *em_table; unsigned long cap, prev_cap = 0; @@ -636,12 +660,9 @@ int em_dev_register_perf_domain(struct device *dev, unsigned int nr_states, unlock: mutex_unlock(&em_pd_mutex); - if (_is_cpu_device(dev)) - em_check_capacity_update(); - return ret; } -EXPORT_SYMBOL_GPL(em_dev_register_perf_domain); +EXPORT_SYMBOL_GPL(em_dev_register_pd_no_update); /** * em_dev_unregister_perf_domain() - Unregister Energy Model (EM) for a device -- cgit v1.2.3 From 449c9c02537a146ac97ef962327a221e21c9cab3 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 10 Sep 2025 11:41:59 +0200 Subject: PM: hibernate: Restrict GFP mask in hibernation_snapshot() Commit 12ffc3b1513e ("PM: Restrict swap use to later in the suspend sequence") incorrectly removed a pm_restrict_gfp_mask() call from hibernation_snapshot(), so memory allocations involving swap are not prevented from being carried out in this code path any more which may lead to serious breakage. The symptoms of such breakage have become visible after adding a shrink_shmem_memory() call to hibernation_snapshot() in commit 2640e819474f ("PM: hibernate: shrink shmem pages after dev_pm_ops.prepare()") which caused this problem to be much more likely to manifest itself. However, since commit 2640e819474f was initially present in the DRM tree that did not include commit 12ffc3b1513e, the symptoms of this issue were not visible until merge commit 260f6f4fda93 ("Merge tag 'drm-next-2025-07-30' of https://gitlab.freedesktop.org/drm/kernel") that exposed it through an entirely reasonable merge conflict resolution. Fixes: 12ffc3b1513e ("PM: Restrict swap use to later in the suspend sequence") Closes: https://bugzilla.kernel.org/show_bug.cgi?id=220555 Reported-by: Todd Brandt Tested-by: Todd Brandt Cc: 6.16+ # 6.16+ Signed-off-by: Rafael J. Wysocki Reviewed-by: Mario Limonciello (AMD) --- kernel/power/hibernate.c | 1 + 1 file changed, 1 insertion(+) (limited to 'kernel') diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index 1f1f30cca573..2f66ab453823 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -449,6 +449,7 @@ int hibernation_snapshot(int platform_mode) shrink_shmem_memory(); console_suspend_all(); + pm_restrict_gfp_mask(); error = dpm_suspend(PMSG_FREEZE); -- cgit v1.2.3 From e25ddfb388c8b7e5f20e3bf38d627fb485003781 Mon Sep 17 00:00:00 2001 From: Leon Hwang Date: Wed, 10 Sep 2025 20:57:39 +0800 Subject: bpf: Reject bpf_timer for PREEMPT_RT When enable CONFIG_PREEMPT_RT, the kernel will warn when run timer selftests by './test_progs -t timer': BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:48 In order to avoid such warning, reject bpf_timer in verifier when PREEMPT_RT is enabled. Signed-off-by: Leon Hwang Link: https://lore.kernel.org/r/20250910125740.52172-2-leon.hwang@linux.dev Signed-off-by: Alexei Starovoitov --- kernel/bpf/verifier.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'kernel') diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index c89e2b1bc644..9fb1f957a093 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -8547,6 +8547,10 @@ static int process_timer_func(struct bpf_verifier_env *env, int regno, verifier_bug(env, "Two map pointers in a timer helper"); return -EFAULT; } + if (IS_ENABLED(CONFIG_PREEMPT_RT)) { + verbose(env, "bpf_timer cannot be used for PREEMPT_RT.\n"); + return -EOPNOTSUPP; + } meta->map_uid = reg->map_uid; meta->map_ptr = map; return 0; -- cgit v1.2.3