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2025-02-21locking/mutex: Add MUTEX_WARN_ON() into fast pathYunhui Cui
Scenario: In platform_device_register, the driver misuses struct device as platform_data, making kmemdup duplicate a device. Accessing the duplicate may cause list corruption due to its mutex magic or list holding old content. It recurs randomly as the first mutex - getting process skips the slow path and mutex check. Adding MUTEX_WARN_ON(lock->magic!= lock) in __mutex_trylock_fast() makes it always happen. Signed-off-by: Yunhui Cui <cuiyunhui@bytedance.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20250126033243.53069-1-cuiyunhui@bytedance.com
2025-02-21irqchip: Have CONFIG_IRQ_MSI_IOMMU be selected by irqchips that need itJason Gunthorpe
Currently, IRQ_MSI_IOMMU is selected if DMA_IOMMU is available to provide an implementation for iommu_dma_prepare/compose_msi_msg(). However, it'll make more sense for irqchips that call prepare/compose to select it, and that will trigger all the additional code and data to be compiled into the kernel. If IRQ_MSI_IOMMU is selected with no IOMMU side implementation, then the prepare/compose() will be NOP stubs. If IRQ_MSI_IOMMU is not selected by an irqchip, then the related code on the iommu side is compiled out. Link: https://patch.msgid.link/r/a2620f67002c5cdf974e89ca3bf905f5c0817be6.1740014950.git.nicolinc@nvidia.com Signed-off-by: Nicolin Chen <nicolinc@nvidia.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2025-02-21tracing: Fix memory leak when reading set_event fileAdrian Huang
kmemleak reports the following memory leak after reading set_event file: # cat /sys/kernel/tracing/set_event # cat /sys/kernel/debug/kmemleak unreferenced object 0xff110001234449e0 (size 16): comm "cat", pid 13645, jiffies 4294981880 hex dump (first 16 bytes): 01 00 00 00 00 00 00 00 a8 71 e7 84 ff ff ff ff .........q...... backtrace (crc c43abbc): __kmalloc_cache_noprof+0x3ca/0x4b0 s_start+0x72/0x2d0 seq_read_iter+0x265/0x1080 seq_read+0x2c9/0x420 vfs_read+0x166/0xc30 ksys_read+0xf4/0x1d0 do_syscall_64+0x79/0x150 entry_SYSCALL_64_after_hwframe+0x76/0x7e The issue can be reproduced regardless of whether set_event is empty or not. Here is an example about the valid content of set_event. # cat /sys/kernel/tracing/set_event sched:sched_process_fork sched:sched_switch sched:sched_wakeup *:*:mod:trace_events_sample The root cause is that s_next() returns NULL when nothing is found. This results in s_stop() attempting to free a NULL pointer because its parameter is NULL. Fix the issue by freeing the memory appropriately when s_next() fails to find anything. Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Link: https://lore.kernel.org/20250220031528.7373-1-ahuang12@lenovo.com Fixes: b355247df104 ("tracing: Cache ":mod:" events for modules not loaded yet") Signed-off-by: Adrian Huang <ahuang12@lenovo.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-02-21ftrace: Correct preemption accounting for function tracing.Sebastian Andrzej Siewior
The function tracer should record the preemption level at the point when the function is invoked. If the tracing subsystem decrement the preemption counter it needs to correct this before feeding the data into the trace buffer. This was broken in the commit cited below while shifting the preempt-disabled section. Use tracing_gen_ctx_dec() which properly subtracts one from the preemption counter on a preemptible kernel. Cc: stable@vger.kernel.org Cc: Wander Lairson Costa <wander@redhat.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/20250220140749.pfw8qoNZ@linutronix.de Fixes: ce5e48036c9e7 ("ftrace: disable preemption when recursion locked") Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Tested-by: Wander Lairson Costa <wander@redhat.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-02-21fprobe: Fix accounting of when to unregister from function graphSteven Rostedt
When adding a new fprobe, it will update the function hash to the functions the fprobe is attached to and register with function graph to have it call the registered functions. The fprobe_graph_active variable keeps track of the number of fprobes that are using function graph. If two fprobes attach to the same function, it increments the fprobe_graph_active for each of them. But when they are removed, the first fprobe to be removed will see that the function it is attached to is also used by another fprobe and it will not remove that function from function_graph. The logic will skip decrementing the fprobe_graph_active variable. This causes the fprobe_graph_active variable to not go to zero when all fprobes are removed, and in doing so it does not unregister from function graph. As the fgraph ops hash will now be empty, and an empty filter hash means all functions are enabled, this triggers function graph to add a callback to the fprobe infrastructure for every function! # echo "f:myevent1 kernel_clone" >> /sys/kernel/tracing/dynamic_events # echo "f:myevent2 kernel_clone%return" >> /sys/kernel/tracing/dynamic_events # cat /sys/kernel/tracing/enabled_functions kernel_clone (1) tramp: 0xffffffffc0024000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60 # > /sys/kernel/tracing/dynamic_events # cat /sys/kernel/tracing/enabled_functions trace_initcall_start_cb (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170 run_init_process (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170 try_to_run_init_process (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170 x86_pmu_show_pmu_cap (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170 cleanup_rapl_pmus (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170 uncore_free_pcibus_map (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170 uncore_types_exit (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170 uncore_pci_exit.part.0 (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170 kvm_shutdown (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170 vmx_dump_msrs (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170 [..] # cat /sys/kernel/tracing/enabled_functions | wc -l 54702 If a fprobe is being removed and all its functions are also traced by other fprobes, still decrement the fprobe_graph_active counter. Cc: stable@vger.kernel.org Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Link: https://lore.kernel.org/20250220202055.565129766@goodmis.org Fixes: 4346ba1604093 ("fprobe: Rewrite fprobe on function-graph tracer") Closes: https://lore.kernel.org/all/20250217114918.10397-A-hca@linux.ibm.com/ Reported-by: Heiko Carstens <hca@linux.ibm.com> Tested-by: Heiko Carstens <hca@linux.ibm.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-02-21fprobe: Always unregister fgraph function from opsSteven Rostedt
When the last fprobe is removed, it calls unregister_ftrace_graph() to remove the graph_ops from function graph. The issue is when it does so, it calls return before removing the function from its graph ops via ftrace_set_filter_ips(). This leaves the last function lingering in the fprobe's fgraph ops and if a probe is added it also enables that last function (even though the callback will just drop it, it does add unneeded overhead to make that call). # echo "f:myevent1 kernel_clone" >> /sys/kernel/tracing/dynamic_events # cat /sys/kernel/tracing/enabled_functions kernel_clone (1) tramp: 0xffffffffc02f3000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60 # echo "f:myevent2 schedule_timeout" >> /sys/kernel/tracing/dynamic_events # cat /sys/kernel/tracing/enabled_functions kernel_clone (1) tramp: 0xffffffffc02f3000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60 schedule_timeout (1) tramp: 0xffffffffc02f3000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60 # > /sys/kernel/tracing/dynamic_events # cat /sys/kernel/tracing/enabled_functions # echo "f:myevent3 kmem_cache_free" >> /sys/kernel/tracing/dynamic_events # cat /sys/kernel/tracing/enabled_functions kmem_cache_free (1) tramp: 0xffffffffc0219000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60 schedule_timeout (1) tramp: 0xffffffffc0219000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60 The above enabled a fprobe on kernel_clone, and then on schedule_timeout. The content of the enabled_functions shows the functions that have a callback attached to them. The fprobe attached to those functions properly. Then the fprobes were cleared, and enabled_functions was empty after that. But after adding a fprobe on kmem_cache_free, the enabled_functions shows that the schedule_timeout was attached again. This is because it was still left in the fprobe ops that is used to tell function graph what functions it wants callbacks from. Cc: stable@vger.kernel.org Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Link: https://lore.kernel.org/20250220202055.393254452@goodmis.org Fixes: 4346ba1604093 ("fprobe: Rewrite fprobe on function-graph tracer") Tested-by: Heiko Carstens <hca@linux.ibm.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-02-21ftrace: Do not add duplicate entries in subops manager opsSteven Rostedt
Check if a function is already in the manager ops of a subops. A manager ops contains multiple subops, and if two or more subops are tracing the same function, the manager ops only needs a single entry in its hash. Cc: stable@vger.kernel.org Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Link: https://lore.kernel.org/20250220202055.226762894@goodmis.org Fixes: 4f554e955614f ("ftrace: Add ftrace_set_filter_ips function") Tested-by: Heiko Carstens <hca@linux.ibm.com> Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-02-21ftrace: Fix accounting of adding subops to a manager opsSteven Rostedt
Function graph uses a subops and manager ops mechanism to attach to ftrace. The manager ops connects to ftrace and the functions it connects to is defined by a list of subops that it manages. The function hash that defines what the above ops attaches to limits the functions to attach if the hash has any content. If the hash is empty, it means to trace all functions. The creation of the manager ops hash is done by iterating over all the subops hashes. If any of the subops hashes is empty, it means that the manager ops hash must trace all functions as well. The issue is in the creation of the manager ops. When a second subops is attached, a new hash is created by starting it as NULL and adding the subops one at a time. But the NULL ops is mistaken as an empty hash, and once an empty hash is found, it stops the loop of subops and just enables all functions. # echo "f:myevent1 kernel_clone" >> /sys/kernel/tracing/dynamic_events # cat /sys/kernel/tracing/enabled_functions kernel_clone (1) tramp: 0xffffffffc0309000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60 # echo "f:myevent2 schedule_timeout" >> /sys/kernel/tracing/dynamic_events # cat /sys/kernel/tracing/enabled_functions trace_initcall_start_cb (1) tramp: 0xffffffffc0309000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60 run_init_process (1) tramp: 0xffffffffc0309000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60 try_to_run_init_process (1) tramp: 0xffffffffc0309000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60 x86_pmu_show_pmu_cap (1) tramp: 0xffffffffc0309000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60 cleanup_rapl_pmus (1) tramp: 0xffffffffc0309000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60 uncore_free_pcibus_map (1) tramp: 0xffffffffc0309000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60 uncore_types_exit (1) tramp: 0xffffffffc0309000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60 uncore_pci_exit.part.0 (1) tramp: 0xffffffffc0309000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60 kvm_shutdown (1) tramp: 0xffffffffc0309000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60 vmx_dump_msrs (1) tramp: 0xffffffffc0309000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60 vmx_cleanup_l1d_flush (1) tramp: 0xffffffffc0309000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60 [..] Fix this by initializing the new hash to NULL and if the hash is NULL do not treat it as an empty hash but instead allocate by copying the content of the first sub ops. Then on subsequent iterations, the new hash will not be NULL, but the content of the previous subops. If that first subops attached to all functions, then new hash may assume that the manager ops also needs to attach to all functions. Cc: stable@vger.kernel.org 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: Heiko Carstens <hca@linux.ibm.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Link: https://lore.kernel.org/20250220202055.060300046@goodmis.org Fixes: 5fccc7552ccbc ("ftrace: Add subops logic to allow one ops to manage many") Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-02-21mm/memremap: Pass down MEMREMAP_* flags to arch_memremap_wb()Kirill A. Shutemov
x86 version of arch_memremap_wb() needs the flags to decide if the mapping has to be encrypted or decrypted. Pass down the flag to arch_memremap_wb(). All current implementations ignore the argument. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: linux-mm@kvack.org Link: https://lore.kernel.org/r/20250217163822.343400-2-kirill.shutemov@linux.intel.com
2025-02-21Merge tag 'v6.14-rc3' into x86/mm, to pick up fixes before merging new changesIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2025-02-21perf/core: Move perf_event sysctls into kernel/eventsJoel Granados
Move ctl tables to two files: - perf_event_{paranoid,mlock_kb,max_sample_rate} and perf_cpu_time_max_percent into kernel/events/core.c - perf_event_max_{stack,context_per_stack} into kernel/events/callchain.c Make static variables and functions that are fully contained in core.c and callchain.cand remove them from include/linux/perf_event.h. Additionally six_hundred_forty_kb is moved to callchain.c. Two new sysctl tables are added ({callchain,events_core}_sysctl_table) with their respective sysctl registration functions. This is part of a greater effort to move ctl tables into their respective subsystems which will reduce the merge conflicts in kerenel/sysctl.c. Signed-off-by: Joel Granados <joel.granados@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20250218-jag-mv_ctltables-v1-5-cd3698ab8d29@kernel.org
2025-02-21Merge branch 'perf/urgent' into perf/core, to pick up fixes before merging ↵Ingo Molnar
new patches Signed-off-by: Ingo Molnar <mingo@kernel.org>
2025-02-21rseq: Fix rseq registration with CONFIG_DEBUG_RSEQMichael Jeanson
With CONFIG_DEBUG_RSEQ=y, at rseq registration the read-only fields are copied from user-space, if this copy fails the syscall returns -EFAULT and the registration should not be activated - but it erroneously is. Move the activation of the registration after the copy of the fields to fix this bug. Fixes: 7d5265ffcd8b ("rseq: Validate read-only fields under DEBUG_RSEQ config") Signed-off-by: Michael Jeanson <mjeanson@efficios.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Link: https://lore.kernel.org/r/20250219205330.324770-1-mjeanson@efficios.com
2025-02-21kcmp: improve performance adding an unlikely hint to task comparisonsColin Ian King
Adding an unlikely() hint on task comparisons on an unlikely error return path improves run-time performance of the kcmp system call. Benchmarking on an i9-12900 shows an improvement of ~5.5% on kcmp(). Results based on running 20 tests with turbo disabled (to reduce clock freq turbo changes), with 10 second run per test and comparing the number of kcmp calls per second. The % Standard deviation of 20 tests was ~0.25%, results are reliable. Signed-off-by: Colin Ian King <colin.i.king@gmail.com> Link: https://lore.kernel.org/r/20250213163916.709392-1-colin.i.king@gmail.com Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-02-21vdso: Remove remnants of architecture-specific time storageThomas Weißschuh
All users of the time releated parts of the vDSO are now using the generic storage implementation. Remove the therefore unnecessary compatibility accessor functions and symbols. Co-developed-by: Nam Cao <namcao@linutronix.de> Signed-off-by: Nam Cao <namcao@linutronix.de> Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250204-vdso-store-rng-v3-18-13a4669dfc8c@linutronix.de
2025-02-21vdso: Add generic time data storageThomas Weißschuh
Historically each architecture defined their own way to store the vDSO data page. Add a generic mechanism to provide storage for that page. Furthermore this generic storage will be extended to also provide uniform storage for *non*-time-related data, like the random state or architecture-specific data. These will have their own pages and data structures, so rename 'vdso_data' into 'vdso_time_data' to make that split clear from the name. Also introduce a new consistent naming scheme for the symbols related to the vDSO, which makes it clear if the symbol is accessible from userspace or kernel space and the type of data behind the symbol. The generic fault handler contains an optimization to prefault the vvar page when the timens page is accessed. This was lifted from s390 and x86. Co-developed-by: Nam Cao <namcao@linutronix.de> Signed-off-by: Nam Cao <namcao@linutronix.de> Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250204-vdso-store-rng-v3-5-13a4669dfc8c@linutronix.de
2025-02-21kernel: Fix "select" wording on HZ_250 descriptionBagas Sanjaya
HZ_250 config description contains alternative choice for NTSC media users (HZ_300), which is written as "selected 300Hz". This is incorrect, as it implies that HZ_300 is automatically selected whereas the user has chosen HZ_250 instead. Fix the wording to "select 300Hz". Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com> Link: https://lore.kernel.org/r/20250203025000.17953-1-bagasdotme@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-20bpf: Do not allow tail call in strcut_ops program with __ref argumentAmery Hung
Reject struct_ops programs with refcounted kptr arguments (arguments tagged with __ref suffix) that tail call. Once a refcounted kptr is passed to a struct_ops program from the kernel, it can be freed or xchged into maps. As there is no guarantee a callee can get the same valid refcounted kptr in the ctx, we cannot allow such usage. Signed-off-by: Amery Hung <ameryhung@gmail.com> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20250220221532.1079331-1-ameryhung@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-02-20bpf: Use preempt_count() directly in bpf_send_signal_common()Hou Tao
bpf_send_signal_common() uses preemptible() to check whether or not the current context is preemptible. If it is preemptible, it will use irq_work to send the signal asynchronously instead of trying to hold a spin-lock, because spin-lock is sleepable under PREEMPT_RT. However, preemptible() depends on CONFIG_PREEMPT_COUNT. When CONFIG_PREEMPT_COUNT is turned off (e.g., CONFIG_PREEMPT_VOLUNTARY=y), !preemptible() will be evaluated as 1 and bpf_send_signal_common() will use irq_work unconditionally. Fix it by unfolding "!preemptible()" and using "preempt_count() != 0 || irqs_disabled()" instead. Fixes: 87c544108b61 ("bpf: Send signals asynchronously if !preemptible") Signed-off-by: Hou Tao <houtao1@huawei.com> Link: https://lore.kernel.org/r/20250220042259.1583319-1-houtao@huaweicloud.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-02-20Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf bpf-6.14-rc4Alexei Starovoitov
Cross-merge bpf fixes after downstream PR (bpf-6.14-rc4). Minor conflict: kernel/bpf/btf.c Adjacent changes: kernel/bpf/arena.c kernel/bpf/btf.c kernel/bpf/syscall.c kernel/bpf/verifier.c mm/memory.c Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-02-20Merge tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpfLinus Torvalds
Pull BPF fixes from Daniel Borkmann: - Fix a soft-lockup in BPF arena_map_free on 64k page size kernels (Alan Maguire) - Fix a missing allocation failure check in BPF verifier's acquire_lock_state (Kumar Kartikeya Dwivedi) - Fix a NULL-pointer dereference in trace_kfree_skb by adding kfree_skb to the raw_tp_null_args set (Kuniyuki Iwashima) - Fix a deadlock when freeing BPF cgroup storage (Abel Wu) - Fix a syzbot-reported deadlock when holding BPF map's freeze_mutex (Andrii Nakryiko) - Fix a use-after-free issue in bpf_test_init when eth_skb_pkt_type is accessing skb data not containing an Ethernet header (Shigeru Yoshida) - Fix skipping non-existing keys in generic_map_lookup_batch (Yan Zhai) - Several BPF sockmap fixes to address incorrect TCP copied_seq calculations, which prevented correct data reads from recv(2) in user space (Jiayuan Chen) - Two fixes for BPF map lookup nullness elision (Daniel Xu) - Fix a NULL-pointer dereference from vmlinux BTF lookup in bpf_sk_storage_tracing_allowed (Jared Kangas) * tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf: selftests: bpf: test batch lookup on array of maps with holes bpf: skip non exist keys in generic_map_lookup_batch bpf: Handle allocation failure in acquire_lock_state bpf: verifier: Disambiguate get_constant_map_key() errors bpf: selftests: Test constant key extraction on irrelevant maps bpf: verifier: Do not extract constant map keys for irrelevant maps bpf: Fix softlockup in arena_map_free on 64k page kernel net: Add rx_skb of kfree_skb to raw_tp_null_args[]. bpf: Fix deadlock when freeing cgroup storage selftests/bpf: Add strparser test for bpf selftests/bpf: Fix invalid flag of recv() bpf: Disable non stream socket for strparser bpf: Fix wrong copied_seq calculation strparser: Add read_sock callback bpf: avoid holding freeze_mutex during mmap operation bpf: unify VM_WRITE vs VM_MAYWRITE use in BPF map mmaping logic selftests/bpf: Adjust data size to have ETH_HLEN bpf, test_run: Fix use-after-free issue in eth_skb_pkt_type() bpf: Remove unnecessary BTF lookups in bpf_sk_storage_tracing_allowed
2025-02-21Merge tag 'drm-misc-fixes-2025-02-20' of ↵Dave Airlie
https://gitlab.freedesktop.org/drm/misc/kernel into drm-fixes An reset signal polarity fix for the jd9365da-h3 panel, a folio handling fix and config fix in nouveau, a dmem cgroup descendant pool handling fix, and a missing header for amdxdna. Signed-off-by: Dave Airlie <airlied@redhat.com> From: Maxime Ripard <mripard@redhat.com> Link: https://patchwork.freedesktop.org/patch/msgid/20250220-glorious-cockle-of-might-5b35f7@houat
2025-02-20bpf: Support selective sampling for bpf timestampingJason Xing
Add the bpf_sock_ops_enable_tx_tstamp kfunc to allow BPF programs to selectively enable TX timestamping on a skb during tcp_sendmsg(). For example, BPF program will limit tracking X numbers of packets and then will stop there instead of tracing all the sendmsgs of matched flow all along. It would be helpful for users who cannot afford to calculate latencies from every sendmsg call probably due to the performance or storage space consideration. Signed-off-by: Jason Xing <kerneljasonxing@gmail.com> Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://patch.msgid.link/20250220072940.99994-12-kerneljasonxing@gmail.com
2025-02-20PM: EM: use kfree_rcu() to simplify the codeLi RongQing
The callback function of call_rcu() just calls kfree(), so use kfree_rcu() instead of call_rcu() + callback function. Signed-off-by: Li RongQing <lirongqing@baidu.com> Reviewed-by: Lukasz Luba <lukasz.luba@arm.com> Link: https://patch.msgid.link/20250218082021.2766-1-lirongqing@baidu.com Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2025-02-20genirq: Introduce irq_can_move_in_process_context()Anup Patel
Interrupt controller drivers which enable CONFIG_GENERIC_PENDING_IRQ require to know whether an interrupt can be moved in process context or not to decide whether they need to invoke the work around for non-atomic MSI updates or not. This information can be retrieved via irq_can_move_pcntxt(). That helper requires access to the top-most interrupt domain data, but the driver which requires this is usually further down in the hierarchy. Introduce irq_can_move_in_process_context() which retrieves that information from the top-most interrupt domain data. [ tglx: Massaged change log ] Signed-off-by: Anup Patel <apatel@ventanamicro.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250217085657.789309-6-apatel@ventanamicro.com
2025-02-20genirq: Introduce common irq_force_complete_move() implementationThomas Gleixner
CONFIG_GENERIC_PENDING_IRQ requires an architecture specific implementation of irq_force_complete_move() for CPU hotplug. At the moment, only x86 implements this unconditionally, but for RISC-V irq_force_complete_move() is only needed when the RISC-V IMSIC driver is in use and not needed otherwise. To allow runtime configuration of this mechanism, introduce a common irq_force_complete_move() implementation in the interrupt core code, which only invokes the completion function, when a interrupt chip in the hierarchy implements it. Switch X86 over to the new mechanism. No functional change intended. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Anup Patel <apatel@ventanamicro.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250217085657.789309-5-apatel@ventanamicro.com
2025-02-19bpf: Add bpf_copy_from_user_task_str() kfuncJordan Rome
This new kfunc will be able to copy a zero-terminated C strings from another task's address space. This is similar to `bpf_copy_from_user_str()` but reads memory of specified task. Signed-off-by: Jordan Rome <linux@jordanrome.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20250213152125.1837400-2-linux@jordanrome.com
2025-02-19VFS: change kern_path_locked() and user_path_locked_at() to never return ↵NeilBrown
negative dentry No callers of kern_path_locked() or user_path_locked_at() want a negative dentry. So change them to return -ENOENT instead. This simplifies callers. This results in a subtle change to bcachefs in that an ioctl will now return -ENOENT in preference to -EXDEV. I believe this restores the behaviour to what it was prior to Commit bbe6a7c899e7 ("bch2_ioctl_subvolume_destroy(): fix locking") Signed-off-by: NeilBrown <neilb@suse.de> Link: https://lore.kernel.org/r/20250217003020.3170652-2-neilb@suse.de Acked-by: Paul Moore <paul@paul-moore.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-02-19cgroup/dmem: Don't open-code css_for_each_descendant_preFriedrich Vock
The current implementation has a bug: If the current css doesn't contain any pool that is a descendant of the "pool" (i.e. when found_descendant == false), then "pool" will point to some unrelated pool. If the current css has a child, we'll overwrite parent_pool with this unrelated pool on the next iteration. Since we can just check whether a pool refers to the same region to determine whether or not it's related, all the additional pool tracking is unnecessary, so just switch to using css_for_each_descendant_pre for traversal. Fixes: b168ed458dde ("kernel/cgroup: Add "dmem" memory accounting cgroup") Signed-off-by: Friedrich Vock <friedrich.vock@gmx.de> Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20250127152754.21325-1-friedrich.vock@gmx.de Signed-off-by: Maarten Lankhorst <dev@lankhorst.se>
2025-02-18bpf: fix env->peak_states computationEduard Zingerman
Compute env->peak_states as a maximum value of sum of env->explored_states and env->free_list size. Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20250215110411.3236773-11-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-02-18bpf: free verifier states when they are no longer referencedEduard Zingerman
When fixes from patches 1 and 3 are applied, Patrick Somaru reported an increase in memory consumption for sched_ext iterator-based programs hitting 1M instructions limit. For example, 2Gb VMs ran out of memory while verifying a program. Similar behaviour could be reproduced on current bpf-next master. Here is an example of such program: /* verification completes if given 16G or RAM, * final env->free_list size is 369,960 entries. */ SEC("raw_tp") __flag(BPF_F_TEST_STATE_FREQ) __success int free_list_bomb(const void *ctx) { volatile char buf[48] = {}; unsigned i, j; j = 0; bpf_for(i, 0, 10) { /* this forks verifier state: * - verification of current path continues and * creates a checkpoint after 'if'; * - verification of forked path hits the * checkpoint and marks it as loop_entry. */ if (bpf_get_prandom_u32()) asm volatile (""); /* this marks 'j' as precise, thus any checkpoint * created on current iteration would not be matched * on the next iteration. */ buf[j++] = 42; j %= ARRAY_SIZE(buf); } asm volatile (""::"r"(buf)); return 0; } Memory consumption increased due to more states being marked as loop entries and eventually added to env->free_list. This commit introduces logic to free states from env->free_list during verification. A state in env->free_list can be freed if: - it has no child states; - it is not used as a loop_entry. This commit: - updates bpf_verifier_state->used_as_loop_entry to be a counter that tracks how many states use this one as a loop entry; - adds a function maybe_free_verifier_state(), which: - frees a state if its ->branches and ->used_as_loop_entry counters are both zero; - if the state is freed, state->loop_entry->used_as_loop_entry is decremented, and an attempt is made to free state->loop_entry. In the example above, this approach reduces the maximum number of states in the free list from 369,960 to 16,223. However, this approach has its limitations. If the buf size in the example above is modified to 64, state caching overflows: the state for j=0 is evicted from the cache before it can be used to stop traversal. As a result, states in the free list accumulate because their branch counters do not reach zero. The effect of this patch on the selftests looks as follows: File Program Max free list (A) Max free list (B) Max free list (DIFF) -------------------------------- ------------------------------------ ----------------- ----------------- -------------------- arena_list.bpf.o arena_list_add 17 3 -14 (-82.35%) bpf_iter_task_stack.bpf.o dump_task_stack 39 9 -30 (-76.92%) iters.bpf.o checkpoint_states_deletion 265 89 -176 (-66.42%) iters.bpf.o clean_live_states 19 0 -19 (-100.00%) profiler2.bpf.o tracepoint__syscalls__sys_enter_kill 102 1 -101 (-99.02%) profiler3.bpf.o tracepoint__syscalls__sys_enter_kill 144 0 -144 (-100.00%) pyperf600_iter.bpf.o on_event 15 0 -15 (-100.00%) pyperf600_nounroll.bpf.o on_event 1170 1158 -12 (-1.03%) setget_sockopt.bpf.o skops_sockopt 18 0 -18 (-100.00%) strobemeta_nounroll1.bpf.o on_event 147 83 -64 (-43.54%) strobemeta_nounroll2.bpf.o on_event 312 209 -103 (-33.01%) strobemeta_subprogs.bpf.o on_event 124 86 -38 (-30.65%) test_cls_redirect_subprogs.bpf.o cls_redirect 15 0 -15 (-100.00%) timer.bpf.o test1 30 15 -15 (-50.00%) Measured using "do-not-submit" patches from here: https://github.com/eddyz87/bpf/tree/get-loop-entry-hungup Reported-by: Patrick Somaru <patsomaru@meta.com> Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20250215110411.3236773-10-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-02-18bpf: use list_head to track explored states and free listEduard Zingerman
The next patch in the set needs the ability to remove individual states from env->free_list while only holding a pointer to the state. Which requires env->free_list to be a doubly linked list. This patch converts env->free_list and struct bpf_verifier_state_list to use struct list_head for this purpose. The change to env->explored_states is collateral. Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20250215110411.3236773-9-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-02-18bpf: do not update state->loop_entry in get_loop_entry()Eduard Zingerman
The patch 9 is simpler if less places modify loop_entry field. The loop deleted by this patch does not affect correctness, but is a performance optimization. However, measurements on selftests and sched_ext programs show that this optimization is unnecessary: - at most 2 steps are done in get_loop_entry(); - most of the time 0 or 1 steps are done in get_loop_entry(). Measured using "do-not-submit" patches from here: https://github.com/eddyz87/bpf/tree/get-loop-entry-hungup Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20250215110411.3236773-8-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-02-18bpf: make state->dfs_depth < state->loop_entry->dfs_depth an invariantEduard Zingerman
For a generic loop detection algorithm a graph node can be a loop header for itself. However, state loop entries are computed for use in is_state_visited(), where get_loop_entry(state)->branches is checked. is_state_visited() also checks state->branches, thus the case when state == state->loop_entry is not interesting for is_state_visited(). This change does not affect correctness, but simplifies get_loop_entry() a bit and also simplifies change to update_loop_entry() in patch 9. Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20250215110411.3236773-7-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-02-18bpf: detect infinite loop in get_loop_entry()Eduard Zingerman
Tejun Heo reported an infinite loop in get_loop_entry(), when verifying a sched_ext program layered_dispatch in [1]. After some investigation I'm sure that root cause is fixed by patches 1,3 in this patch-set. To err on the safe side, this commit modifies get_loop_entry() to detect infinite loops and abort verification in such cases. The number of steps get_loop_entry(S) can make while moving along the bpf_verifier_state->loop_entry chain is bounded by the DFS depth of state S. This fact is exploited to implement the check. To avoid dealing with the potential error code returned from get_loop_entry() in update_loop_entry(), remove the get_loop_entry() calls there: - This change does not affect correctness. Loop entries would still be updated during the backward DFS move in update_branch_counts(). - This change does not affect performance. Measurements show that get_loop_entry() performs at most 1 step on selftests and at most 2 steps on sched_ext programs (1 step in 17 cases, 2 steps in 3 cases, measured using "do-not-submit" patches from [2]). [1] https://github.com/sched-ext/scx/ commit f0b27038ea10 ("XXX - kernel stall") [2] https://github.com/eddyz87/bpf/tree/get-loop-entry-hungup Reported-by: Tejun Heo <tj@kernel.org> Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20250215110411.3236773-6-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-02-18bpf: don't do clean_live_states when state->loop_entry->branches > 0Eduard Zingerman
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>
2025-02-18bpf: copy_verifier_state() should copy 'loop_entry' fieldEduard Zingerman
The bpf_verifier_state.loop_entry state should be copied by copy_verifier_state(). Otherwise, .loop_entry values from unrelated states would poison env->cur_state. Additionally, env->stack should not contain any states with .loop_entry != NULL. The states in env->stack are yet to be verified, while .loop_entry is set for states that reached an equivalent state. This means that env->cur_state->loop_entry should always be NULL after pop_stack(). See the selftest in the next commit for an example of the program that is not safe yet is accepted by verifier w/o this fix. This change has some verification performance impact for selftests: File Program Insns (A) Insns (B) Insns (DIFF) States (A) States (B) States (DIFF) ---------------------------------- ---------------------------- --------- --------- -------------- ---------- ---------- ------------- arena_htab.bpf.o arena_htab_llvm 717 426 -291 (-40.59%) 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_del 309 279 -30 (-9.71%) 23 14 -9 (-39.13%) iters.bpf.o iter_subprog_check_stacksafe 155 141 -14 (-9.03%) 15 14 -1 (-6.67%) iters.bpf.o iter_subprog_iters 1094 1003 -91 (-8.32%) 88 83 -5 (-5.68%) iters.bpf.o loop_state_deps2 479 725 +246 (+51.36%) 46 63 +17 (+36.96%) kmem_cache_iter.bpf.o open_coded_iter 63 59 -4 (-6.35%) 7 6 -1 (-14.29%) verifier_bits_iter.bpf.o max_words 92 84 -8 (-8.70%) 8 7 -1 (-12.50%) verifier_iterating_callbacks.bpf.o cond_break2 113 107 -6 (-5.31%) 12 12 +0 (+0.00%) And significant negative impact for sched_ext: File Program Insns (A) Insns (B) Insns (DIFF) States (A) States (B) States (DIFF) ----------------- ---------------------- --------- --------- -------------------- ---------- ---------- ------------------ bpf.bpf.o lavd_init 7039 14723 +7684 (+109.16%) 490 1139 +649 (+132.45%) bpf.bpf.o layered_dispatch 11485 10548 -937 (-8.16%) 848 762 -86 (-10.14%) bpf.bpf.o layered_dump 7422 1000001 +992579 (+13373.47%) 681 31178 +30497 (+4478.27%) bpf.bpf.o layered_enqueue 16854 71127 +54273 (+322.02%) 1611 6450 +4839 (+300.37%) bpf.bpf.o p2dq_dispatch 665 791 +126 (+18.95%) 68 78 +10 (+14.71%) bpf.bpf.o p2dq_init 2343 2980 +637 (+27.19%) 201 237 +36 (+17.91%) bpf.bpf.o refresh_layer_cpumasks 16487 674760 +658273 (+3992.68%) 1770 65370 +63600 (+3593.22%) bpf.bpf.o rusty_select_cpu 1937 40872 +38935 (+2010.07%) 177 3210 +3033 (+1713.56%) scx_central.bpf.o central_dispatch 636 2687 +2051 (+322.48%) 63 227 +164 (+260.32%) scx_nest.bpf.o nest_init 636 815 +179 (+28.14%) 60 73 +13 (+21.67%) scx_qmap.bpf.o qmap_dispatch 2393 3580 +1187 (+49.60%) 196 253 +57 (+29.08%) scx_qmap.bpf.o qmap_dump 233 318 +85 (+36.48%) 22 30 +8 (+36.36%) scx_qmap.bpf.o qmap_init 16367 17436 +1069 (+6.53%) 603 669 +66 (+10.95%) Note 'layered_dump' program, which now hits 1M instructions limit. This impact would be mitigated in the next patch. Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20250215110411.3236773-2-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-02-18bpf: skip non exist keys in generic_map_lookup_batchYan Zhai
The generic_map_lookup_batch currently returns EINTR if it fails with ENOENT and retries several times on bpf_map_copy_value. The next batch would start from the same location, presuming it's a transient issue. This is incorrect if a map can actually have "holes", i.e. "get_next_key" can return a key that does not point to a valid value. At least the array of maps type may contain such holes legitly. Right now these holes show up, generic batch lookup cannot proceed any more. It will always fail with EINTR errors. Rather, do not retry in generic_map_lookup_batch. If it finds a non existing element, skip to the next key. This simple solution comes with a price that transient errors may not be recovered, and the iteration might cycle back to the first key under parallel deletion. For example, Hou Tao <houtao@huaweicloud.com> pointed out a following scenario: For LPM trie map: (1) ->map_get_next_key(map, prev_key, key) returns a valid key (2) bpf_map_copy_value() return -ENOMENT It means the key must be deleted concurrently. (3) goto next_key It swaps the prev_key and key (4) ->map_get_next_key(map, prev_key, key) again prev_key points to a non-existing key, for LPM trie it will treat just like prev_key=NULL case, the returned key will be duplicated. With the retry logic, the iteration can continue to the key next to the deleted one. But if we directly skip to the next key, the iteration loop would restart from the first key for the lpm_trie type. However, not all races may be recovered. For example, if current key is deleted after instead of before bpf_map_copy_value, or if the prev_key also gets deleted, then the loop will still restart from the first key for lpm_tire anyway. For generic lookup it might be better to stay simple, i.e. just skip to the next key. To guarantee that the output keys are not duplicated, it is better to implement map type specific batch operations, which can properly lock the trie and synchronize with concurrent mutators. Fixes: cb4d03ab499d ("bpf: Add generic support for lookup batch op") Closes: https://lore.kernel.org/bpf/Z6JXtA1M5jAZx8xD@debian.debian/ Signed-off-by: Yan Zhai <yan@cloudflare.com> Acked-by: Hou Tao <houtao1@huawei.com> Link: https://lore.kernel.org/r/85618439eea75930630685c467ccefeac0942e2b.1739171594.git.yan@cloudflare.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-02-18ftrace: Have ftrace pages output reflect freed pagesSteven Rostedt
The amount of memory that ftrace uses to save the descriptors to manage the functions it can trace is shown at output. But if there are a lot of functions that are skipped because they were weak or the architecture added holes into the tables, then the extra pages that were allocated are freed. But these freed pages are not reflected in the numbers shown, and they can even be inconsistent with what is reported: ftrace: allocating 57482 entries in 225 pages ftrace: allocated 224 pages with 3 groups The above shows the number of original entries that are in the mcount_loc section and the pages needed to save them (225), but the second output reflects the number of pages that were actually used. The two should be consistent as: ftrace: allocating 56739 entries in 224 pages ftrace: allocated 224 pages with 3 groups The above also shows the accurate number of entires that were actually stored and does not include the entries that were removed. Cc: bpf <bpf@vger.kernel.org> 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: Peter Zijlstra <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masahiro Yamada <masahiroy@kernel.org> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Nicolas Schier <nicolas@fjasle.eu> Cc: Zheng Yejian <zhengyejian1@huawei.com> Cc: Martin Kelly <martin.kelly@crowdstrike.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Link: https://lore.kernel.org/20250218200023.221100846@goodmis.org Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-02-18ftrace: Update the mcount_loc check of skipped entriesSteven Rostedt
Now that weak functions turn into skipped entries, update the check to make sure the amount that was allocated would fit both the entries that were allocated as well as those that were skipped. Cc: bpf <bpf@vger.kernel.org> 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: Peter Zijlstra <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masahiro Yamada <masahiroy@kernel.org> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Nicolas Schier <nicolas@fjasle.eu> Cc: Zheng Yejian <zhengyejian1@huawei.com> Cc: Martin Kelly <martin.kelly@crowdstrike.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Link: https://lore.kernel.org/20250218200023.055162048@goodmis.org Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-02-18scripts/sorttable: Zero out weak functions in mcount_loc tableSteven Rostedt
When a function is annotated as "weak" and is overridden, the code is not removed. If it is traced, the fentry/mcount location in the weak function will be referenced by the "__mcount_loc" section. This will then be added to the available_filter_functions list. Since only the address of the functions are listed, to find the name to show, a search of kallsyms is used. Since kallsyms will return the function by simply finding the function that the address is after but before the next function, an address of a weak function will show up as the function before it. This is because kallsyms does not save names of weak functions. This has caused issues in the past, as now the traced weak function will be listed in available_filter_functions with the name of the function before it. At best, this will cause the previous function's name to be listed twice. At worse, if the previous function was marked notrace, it will now show up as a function that can be traced. Note that it only shows up that it can be traced but will not be if enabled, which causes confusion. https://lore.kernel.org/all/20220412094923.0abe90955e5db486b7bca279@kernel.org/ The commit b39181f7c6907 ("ftrace: Add FTRACE_MCOUNT_MAX_OFFSET to avoid adding weak function") was a workaround to this by checking the function address before printing its name. If the address was too far from the function given by the name then instead of printing the name it would print: __ftrace_invalid_address___<invalid-offset> The real issue is that these invalid addresses are listed in the ftrace table look up which available_filter_functions is derived from. A place holder must be listed in that file because set_ftrace_filter may take a series of indexes into that file instead of names to be able to do O(1) lookups to enable filtering (many tools use this method). Even if kallsyms saved the size of the function, it does not remove the need of having these place holders. The real solution is to not add a weak function into the ftrace table in the first place. To solve this, the sorttable.c code that sorts the mcount regions during the build is modified to take a "nm -S vmlinux" input, sort it, and any function listed in the mcount_loc section that is not within a boundary of the function list given by nm is considered a weak function and is zeroed out. Note, this does not mean they will remain zero when booting as KASLR will still shift those addresses. To handle this, the entries in the mcount_loc section will be ignored if they are zero or match the kaslr_offset() value. Before: ~# grep __ftrace_invalid_address___ /sys/kernel/tracing/available_filter_functions | wc -l 551 After: ~# grep __ftrace_invalid_address___ /sys/kernel/tracing/available_filter_functions | wc -l 0 Cc: bpf <bpf@vger.kernel.org> 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: Peter Zijlstra <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masahiro Yamada <masahiroy@kernel.org> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Nicolas Schier <nicolas@fjasle.eu> Cc: Zheng Yejian <zhengyejian1@huawei.com> Cc: Martin Kelly <martin.kelly@crowdstrike.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Link: https://lore.kernel.org/20250218200022.883095980@goodmis.org Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-02-18PM: EM: Slightly reduce em_check_capacity_update() overheadRafael J. Wysocki
Every iteration of the loop over all possible CPUs in em_check_capacity_update() causes get_cpu_device() to be called twice for the same CPU, once indirectly via em_cpu_get() and once directly. Get rid of the indirect get_cpu_device() call by moving the direct invocation of it earlier and using em_pd_get() instead of em_cpu_get() to get a pd pointer for the dev one returned by it. This also exposes the fact that dev is needed to get a pd, so the code becomes somewhat easier to follow after it. No functional impact. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Lukasz Luba <lukasz.luba@arm.com> Link: https://patch.msgid.link/1925950.tdWV9SEqCh@rjwysocki.net
2025-02-18PM: EM: Drop unused parameter from em_adjust_new_capacity()Rafael J. Wysocki
The max_cap parameter is never used in em_adjust_new_capacity(), so drop it. No functional impact. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Lukasz Luba <lukasz.luba@arm.com> Link: https://patch.msgid.link/2369979.ElGaqSPkdT@rjwysocki.net
2025-02-18PM: hibernate: Replace deprecated kmap_atomic() with kmap_local_page()David Reaver
kmap_atomic() is deprecated and should be replaced with kmap_local_page() [1][2]. kmap_local_page() is faster in kernels with HIGHMEM enabled, can take page faults, and allows preemption. According to [2], this replacement is safe as long as the code between kmap_atomic() and kunmap_atomic() does not implicitly depend on disabling page faults or preemption. In all of the call sites in this patch, the only thing happening between mapping and unmapping pages is copy_page() calls, and I don't suspect they depend on disabling page faults or preemption. Link: https://lwn.net/Articles/836144/ [1] Link: https://docs.kernel.org/mm/highmem.html#temporary-virtual-mappings [2] Signed-off-by: David Reaver <me@davidreaver.com> Link: https://patch.msgid.link/20250112152658.20132-1-me@davidreaver.com Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2025-02-18sched_ext: idle: Introduce node-aware idle cpu kfunc helpersAndrea Righi
Introduce a new kfunc to retrieve the node associated to a CPU: int scx_bpf_cpu_node(s32 cpu) Add the following kfuncs to provide BPF schedulers direct access to per-node idle cpumasks information: const struct cpumask *scx_bpf_get_idle_cpumask_node(int node) const struct cpumask *scx_bpf_get_idle_smtmask_node(int node) s32 scx_bpf_pick_idle_cpu_node(const cpumask_t *cpus_allowed, int node, u64 flags) s32 scx_bpf_pick_any_cpu_node(const cpumask_t *cpus_allowed, int node, u64 flags) Moreover, trigger an scx error when any of the non-node aware idle CPU kfuncs are used when SCX_OPS_BUILTIN_IDLE_PER_NODE is enabled. Cc: Yury Norov [NVIDIA] <yury.norov@gmail.com> Signed-off-by: Andrea Righi <arighi@nvidia.com> Reviewed-by: Yury Norov [NVIDIA] <yury.norov@gmail.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-02-18x86: Move sysctls into arch/x86Joel Granados
Move the following sysctl tables into arch/x86/kernel/setup.c: panic_on_{unrecoverable_nmi,io_nmi} bootloader_{type,version} io_delay_type unknown_nmi_panic acpi_realmode_flags Variables moved from include/linux/ to arch/x86/include/asm/ because there is no longer need for them outside arch/x86/kernel: acpi_realmode_flags panic_on_{unrecoverable_nmi,io_nmi} Include <asm/nmi.h> in arch/s86/kernel/setup.h in order to bring in panic_on_{io_nmi,unrecovered_nmi}. This is part of a greater effort to move ctl tables into their respective subsystems which will reduce the merge conflicts in kerenel/sysctl.c. Signed-off-by: Joel Granados <joel.granados@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20250218-jag-mv_ctltables-v1-8-cd3698ab8d29@kernel.org
2025-02-18Merge tag 'v6.14-rc3' into x86/core, to pick up fixesIngo Molnar
Pick up upstream x86 fixes before applying new patches. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2025-02-18can: Switch to use hrtimer_setup()Nam Cao
hrtimer_setup() takes the callback function pointer as argument and initializes the timer completely. Replace hrtimer_init() and the open coded initialization of hrtimer::function with the new setup mechanism. Most of this patch is generated by Coccinelle. Except for the TX thrtimer in bcm_tx_setup() because this timer is not used and the callback function is never set. For this particular case, set the callback to hrtimer_dummy_timeout() Signed-off-by: Nam Cao <namcao@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Marc Kleine-Budde <mkl@pengutronix.de> Link: https://lore.kernel.org/all/a3a6be42c818722ad41758457408a32163bfd9a0.1738746872.git.namcao@linutronix.de
2025-02-18tracing/osnoise: Switch to use hrtimer_setup()Nam Cao
hrtimer_setup() takes the callback function pointer as argument and initializes the timer completely. Replace hrtimer_init() and the open coded initialization of hrtimer::function with the new setup mechanism. Patch was created by using Coccinelle. Signed-off-by: Nam Cao <namcao@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org> Link: https://lore.kernel.org/all/ff8e6e11df5f928b2b97619ac847b4fa045376a1.1738746821.git.namcao@linutronix.de
2025-02-18watchdog: Switch to use hrtimer_setup()Nam Cao
hrtimer_setup() takes the callback function pointer as argument and initializes the timer completely. Replace hrtimer_init() and the open coded initialization of hrtimer::function with the new setup mechanism. Patch was created by using Coccinelle. Signed-off-by: Nam Cao <namcao@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/a5c62f2b5e1ea1cf4d32f37bc2d21a8eeab2f875.1738746821.git.namcao@linutronix.de