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2024-05-14mm/execmem, arch: convert remaining overrides of module_alloc to execmemMike Rapoport (IBM)1-20/+6
Extend execmem parameters to accommodate more complex overrides of module_alloc() by architectures. This includes specification of a fallback range required by arm, arm64 and powerpc, EXECMEM_MODULE_DATA type required by powerpc, support for allocation of KASAN shadow required by s390 and x86 and support for late initialization of execmem required by arm64. The core implementation of execmem_alloc() takes care of suppressing warnings when the initial allocation fails but there is a fallback range defined. Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org> Acked-by: Will Deacon <will@kernel.org> Acked-by: Song Liu <song@kernel.org> Tested-by: Liviu Dudau <liviu@dudau.co.uk> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2024-05-14mm: introduce execmem_alloc() and execmem_free()Mike Rapoport (IBM)4-24/+16
module_alloc() is used everywhere as a mean to allocate memory for code. Beside being semantically wrong, this unnecessarily ties all subsystems that need to allocate code, such as ftrace, kprobes and BPF to modules and puts the burden of code allocation to the modules code. Several architectures override module_alloc() because of various constraints where the executable memory can be located and this causes additional obstacles for improvements of code allocation. Start splitting code allocation from modules by introducing execmem_alloc() and execmem_free() APIs. Initially, execmem_alloc() is a wrapper for module_alloc() and execmem_free() is a replacement of module_memfree() to allow updating all call sites to use the new APIs. Since architectures define different restrictions on placement, permissions, alignment and other parameters for memory that can be used by different subsystems that allocate executable memory, execmem_alloc() takes a type argument, that will be used to identify the calling subsystem and to allow architectures define parameters for ranges suitable for that subsystem. No functional changes. Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Acked-by: Song Liu <song@kernel.org> Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2024-05-14module: make module_memory_{alloc,free} more self-containedMike Rapoport (IBM)1-25/+39
Move the logic related to the memory allocation and freeing into module_memory_alloc() and module_memory_free(). Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org> Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org> Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Acked-by: Song Liu <song@kernel.org> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2024-05-14kallsyms: replace deprecated strncpy with strscpyJustin Stitt1-1/+1
strncpy() is deprecated for use on NUL-terminated destination strings [1] and as such we should prefer more robust and less ambiguous string interfaces. The goal is to remove its use completely [2]. namebuf is eventually cleaned of any trailing llvm suffixes using strstr(). This hints that namebuf should be NUL-terminated. static void cleanup_symbol_name(char *s) { char *res; ... res = strstr(s, ".llvm."); ... } Due to this, use strscpy() over strncpy() as it guarantees NUL-termination on the destination buffer. Drop the -1 from the length calculation as it is no longer needed to ensure NUL-termination. Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1] Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html Link: https://github.com/KSPP/linux/issues/90 [2] Cc: linux-hardening@vger.kernel.org Signed-off-by: Justin Stitt <justinstitt@google.com> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2024-05-14module: allow UNUSED_KSYMS_WHITELIST to be relative against objtree.Yifan Hong1-1/+1
If UNUSED_KSYMS_WHITELIST is a file generated before Kbuild runs, and the source tree is in a read-only filesystem, the developer must put the file somewhere and specify an absolute path to UNUSED_KSYMS_WHITELIST. This worked, but if IKCONFIG=y, an absolute path is embedded into .config and eventually into vmlinux, causing the build to be less reproducible when building on a different machine. This patch makes the handling of UNUSED_KSYMS_WHITELIST to be similar to MODULE_SIG_KEY. First, check if UNUSED_KSYMS_WHITELIST is an absolute path, just as before this patch. If so, use the path as is. If it is a relative path, use wildcard to check the existence of the file below objtree first. If it does not exist, fall back to the original behavior of adding $(srctree)/ before the value. After this patch, the developer can put the generated file in objtree, then use a relative path against objtree in .config, eradicating any absolute paths that may be evaluated differently on different machines. Signed-off-by: Yifan Hong <elsk@google.com> Reviewed-by: Elliot Berman <quic_eberman@quicinc.com> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2024-05-14Merge tag 'sched-core-2024-05-13' of ↵Linus Torvalds11-325/+381
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Ingo Molnar: - Add cpufreq pressure feedback for the scheduler - Rework misfit load-balancing wrt affinity restrictions - Clean up and simplify the code around ::overutilized and ::overload access. - Simplify sched_balance_newidle() - Bump SCHEDSTAT_VERSION to 16 due to a cleanup of CPU_MAX_IDLE_TYPES handling that changed the output. - Rework & clean up <asm/vtime.h> interactions wrt arch_vtime_task_switch() - Reorganize, clean up and unify most of the higher level scheduler balancing function names around the sched_balance_*() prefix - Simplify the balancing flag code (sched_balance_running) - Miscellaneous cleanups & fixes * tag 'sched-core-2024-05-13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (50 commits) sched/pelt: Remove shift of thermal clock sched/cpufreq: Rename arch_update_thermal_pressure() => arch_update_hw_pressure() thermal/cpufreq: Remove arch_update_thermal_pressure() sched/cpufreq: Take cpufreq feedback into account cpufreq: Add a cpufreq pressure feedback for the scheduler sched/fair: Fix update of rd->sg_overutilized sched/vtime: Do not include <asm/vtime.h> header s390/irq,nmi: Include <asm/vtime.h> header directly s390/vtime: Remove unused __ARCH_HAS_VTIME_TASK_SWITCH leftover sched/vtime: Get rid of generic vtime_task_switch() implementation sched/vtime: Remove confusing arch_vtime_task_switch() declaration sched/balancing: Simplify the sg_status bitmask and use separate ->overloaded and ->overutilized flags sched/fair: Rename set_rd_overutilized_status() to set_rd_overutilized() sched/fair: Rename SG_OVERLOAD to SG_OVERLOADED sched/fair: Rename {set|get}_rd_overload() to {set|get}_rd_overloaded() sched/fair: Rename root_domain::overload to ::overloaded sched/fair: Use helper functions to access root_domain::overload sched/fair: Check root_domain::overload value before update sched/fair: Combine EAS check with root_domain::overutilized access sched/fair: Simplify the continue_balancing logic in sched_balance_newidle() ...
2024-05-14Merge tag 'perf-core-2024-05-13' of ↵Linus Torvalds2-129/+148
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf events updates from Ingo Molnar: - Combine perf and BPF for fast evalution of HW breakpoint conditions - Add LBR capture support outside of hardware events - Trigger IO signals for watermark_wakeup - Add RAPL support for Intel Arrow Lake and Lunar Lake - Optimize frequency-throttling - Miscellaneous cleanups & fixes * tag 'perf-core-2024-05-13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (21 commits) perf/bpf: Mark perf_event_set_bpf_handler() and perf_event_free_bpf_handler() as inline too selftests/perf_events: Test FASYNC with watermark wakeups perf/ring_buffer: Trigger IO signals for watermark_wakeup perf: Move perf_event_fasync() to perf_event.h perf/bpf: Change the !CONFIG_BPF_SYSCALL stubs to static inlines selftest/bpf: Test a perf BPF program that suppresses side effects perf/bpf: Allow a BPF program to suppress all sample side effects perf/bpf: Remove unneeded uses_default_overflow_handler() perf/bpf: Call BPF handler directly, not through overflow machinery perf/bpf: Remove #ifdef CONFIG_BPF_SYSCALL from struct perf_event members perf/bpf: Create bpf_overflow_handler() stub for !CONFIG_BPF_SYSCALL perf/bpf: Reorder bpf_overflow_handler() ahead of __perf_event_overflow() perf/x86/rapl: Add support for Intel Lunar Lake perf/x86/rapl: Add support for Intel Arrow Lake perf/core: Reduce PMU access to adjust sample freq perf/core: Optimize perf_adjust_freq_unthr_context() perf/x86/amd: Don't reject non-sampling events with configured LBR perf/x86/amd: Support capturing LBR from software events perf/x86/amd: Avoid taking branches before disabling LBR perf/x86/amd: Ensure amd_pmu_core_disable_all() is always inlined ...
2024-05-14Merge tag 'locking-core-2024-05-13' of ↵Linus Torvalds5-38/+83
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking updates from Ingo Molnar: - Over a dozen code generation micro-optimizations for the atomic and spinlock code - Add more __ro_after_init attributes - Robustify the lockdevent_*() macros * tag 'locking-core-2024-05-13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: locking/pvqspinlock/x86: Use _Q_LOCKED_VAL in PV_UNLOCK_ASM macro locking/qspinlock/x86: Micro-optimize virt_spin_lock() locking/atomic/x86: Merge __arch{,_try}_cmpxchg64_emu_local() with __arch{,_try}_cmpxchg64_emu() locking/atomic/x86: Introduce arch_try_cmpxchg64_local() locking/pvqspinlock/x86: Remove redundant CMP after CMPXCHG in __raw_callee_save___pv_queued_spin_unlock() locking/pvqspinlock: Use try_cmpxchg() in qspinlock_paravirt.h locking/pvqspinlock: Use try_cmpxchg_acquire() in trylock_clear_pending() locking/qspinlock: Use atomic_try_cmpxchg_relaxed() in xchg_tail() locking/atomic/x86: Define arch_atomic_sub() family using arch_atomic_add() functions locking/atomic/x86: Rewrite x86_32 arch_atomic64_{,fetch}_{and,or,xor}() functions locking/atomic/x86: Introduce arch_atomic64_read_nonatomic() to x86_32 locking/atomic/x86: Introduce arch_atomic64_try_cmpxchg() to x86_32 locking/atomic/x86: Introduce arch_try_cmpxchg64() for !CONFIG_X86_CMPXCHG64 locking/atomic/x86: Modernize x86_32 arch_{,try_}_cmpxchg64{,_local}() locking/atomic/x86: Correct the definition of __arch_try_cmpxchg128() x86/tsc: Make __use_tsc __ro_after_init x86/kvm: Make kvm_async_pf_enabled __ro_after_init context_tracking: Make context_tracking_key __ro_after_init jump_label,module: Don't alloc static_key_mod for __ro_after_init keys locking/qspinlock: Always evaluate lockevent* non-event parameter once
2024-05-14Merge tag 'v6.10-p1' of ↵Linus Torvalds1-4/+4
git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 Pull crypto updates from Herbert Xu: "API: - Remove crypto stats interface Algorithms: - Add faster AES-XTS on modern x86_64 CPUs - Forbid curves with order less than 224 bits in ecc (FIPS 186-5) - Add ECDSA NIST P521 Drivers: - Expose otp zone in atmel - Add dh fallback for primes > 4K in qat - Add interface for live migration in qat - Use dma for aes requests in starfive - Add full DMA support for stm32mpx in stm32 - Add Tegra Security Engine driver Others: - Introduce scope-based x509_certificate allocation" * tag 'v6.10-p1' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (123 commits) crypto: atmel-sha204a - provide the otp content crypto: atmel-sha204a - add reading from otp zone crypto: atmel-i2c - rename read function crypto: atmel-i2c - add missing arg description crypto: iaa - Use kmemdup() instead of kzalloc() and memcpy() crypto: sahara - use 'time_left' variable with wait_for_completion_timeout() crypto: api - use 'time_left' variable with wait_for_completion_killable_timeout() crypto: caam - i.MX8ULP donot have CAAM page0 access crypto: caam - init-clk based on caam-page0-access crypto: starfive - Use fallback for unaligned dma access crypto: starfive - Do not free stack buffer crypto: starfive - Skip unneeded fallback allocation crypto: starfive - Skip dma setup for zeroed message crypto: hisilicon/sec2 - fix for register offset crypto: hisilicon/debugfs - mask the unnecessary info from the dump crypto: qat - specify firmware files for 402xx crypto: x86/aes-gcm - simplify GCM hash subkey derivation crypto: x86/aes-gcm - delete unused GCM assembly code crypto: x86/aes-xts - simplify loop in xts_crypt_slowpath() hwrng: stm32 - repair clock handling ...
2024-05-14Merge tag 'hardening-6.10-rc1' of ↵Linus Torvalds2-3/+11
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull hardening updates from Kees Cook: "The bulk of the changes here are related to refactoring and expanding the KUnit tests for string helper and fortify behavior. Some trivial strncpy replacements in fs/ were carried in my tree. Also some fixes to SCSI string handling were carried in my tree since the helper for those was introduce here. Beyond that, just little fixes all around: objtool getting confused about LKDTM+KCFI, preparing for future refactors (constification of sysctl tables, additional __counted_by annotations), a Clang UBSAN+i386 crash fix, and adding more options in the hardening.config Kconfig fragment. Summary: - selftests: Add str*cmp tests (Ivan Orlov) - __counted_by: provide UAPI for _le/_be variants (Erick Archer) - Various strncpy deprecation refactors (Justin Stitt) - stackleak: Use a copy of soon-to-be-const sysctl table (Thomas Weißschuh) - UBSAN: Work around i386 -regparm=3 bug with Clang prior to version 19 - Provide helper to deal with non-NUL-terminated string copying - SCSI: Fix older string copying bugs (with new helper) - selftests: Consolidate string helper behavioral tests - selftests: add memcpy() fortify tests - string: Add additional __realloc_size() annotations for "dup" helpers - LKDTM: Fix KCFI+rodata+objtool confusion - hardening.config: Enable KCFI" * tag 'hardening-6.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (29 commits) uapi: stddef.h: Provide UAPI macros for __counted_by_{le, be} stackleak: Use a copy of the ctl_table argument string: Add additional __realloc_size() annotations for "dup" helpers kunit/fortify: Fix replaced failure path to unbreak __alloc_size hardening: Enable KCFI and some other options lkdtm: Disable CFI checking for perms functions kunit/fortify: Add memcpy() tests kunit/fortify: Do not spam logs with fortify WARNs kunit/fortify: Rename tests to use recommended conventions init: replace deprecated strncpy with strscpy_pad kunit/fortify: Fix mismatched kvalloc()/vfree() usage scsi: qla2xxx: Avoid possible run-time warning with long model_num scsi: mpi3mr: Avoid possible run-time warning with long manufacturer strings scsi: mptfusion: Avoid possible run-time warning with long manufacturer strings fs: ecryptfs: replace deprecated strncpy with strscpy hfsplus: refactor copy_name to not use strncpy reiserfs: replace deprecated strncpy with scnprintf virt: acrn: replace deprecated strncpy with strscpy ubsan: Avoid i386 UBSAN handler crashes with Clang ubsan: Remove 1-element array usage in debug reporting ...
2024-05-13Merge tag 'seccomp-6.10-rc1' of ↵Linus Torvalds1-2/+2
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull seccomp update from Kees Cook: - Prepare for sysctl table constification * tag 'seccomp-6.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: seccomp: Constify sysctl subhelpers
2024-05-13Merge tag 'kcsan.2024.05.10a' of ↵Linus Torvalds1-0/+17
git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu Pull kcsan update from Paul McKenney: "Introduce __data_racy type qualifier This adds a __data_racy type qualifier that enables kernel developers to inform KCSAN that a given variable is a shared variable without needing to mark each and every access. This allows pre-KCSAN code to be correctly (if approximately) instrumented withh very little effort, and also provides people reading the code a clear indication that the variable is in fact shared. In addition, it permits incremental transition to per-access KCSAN marking, so that (for example) a given subsystem can be transitioned one variable at a time, while avoiding large numbers of KCSAN warnings during this transition" * tag 'kcsan.2024.05.10a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu: kcsan, compiler_types: Introduce __data_racy type qualifier
2024-05-13Merge tag 'rcu.next.v6.10' of https://github.com/urezki/linuxLinus Torvalds18-111/+580
Pull RCU updates from Uladzislau Rezki: - Fix a lockdep complain for lazy-preemptible kernel, remove redundant BH disable for TINY_RCU, remove redundant READ_ONCE() in tree.c, fix false positives KCSAN splat and fix buffer overflow in the print_cpu_stall_info(). - Misc updates related to bpf, tracing and update the MAINTAINERS file. - An improvement of a normal synchronize_rcu() call in terms of latency. It maintains a separate track for sync. users only. This approach bypasses per-cpu nocb-lists thus sync-users do not depend on nocb-list length and how fast regular callbacks are processed. - RCU tasks: switch tasks RCU grace periods to sleep at TASK_IDLE priority, fix some comments, add some diagnostic warning to the exit_tasks_rcu_start() and fix a buffer overflow in the show_rcu_tasks_trace_gp_kthread(). - RCU torture: Increase memory to guest OS, fix a Tasks Rude RCU testing, some updates for TREE09, dump mode information to debug GP kthread state, remove redundant READ_ONCE(), fix some comments about RCU_TORTURE_PIPE_LEN and pipe_count, remove some redundant pointer initialization, fix a hung splat task by when the rcutorture tests start to exit, fix invalid context warning, add '--do-kvfree' parameter to torture test and use slow register unregister callbacks only for rcutype test. * tag 'rcu.next.v6.10' of https://github.com/urezki/linux: (48 commits) rcutorture: Use rcu_gp_slow_register/unregister() only for rcutype test torture: Scale --do-kvfree test time rcutorture: Fix invalid context warning when enable srcu barrier testing rcutorture: Make stall-tasks directly exit when rcutorture tests end rcutorture: Removing redundant function pointer initialization rcutorture: Make rcutorture support print rcu-tasks gp state rcutorture: Use the gp_kthread_dbg operation specified by cur_ops rcutorture: Re-use value stored to ->rtort_pipe_count instead of re-reading rcutorture: Fix rcu_torture_one_read() pipe_count overflow comment rcutorture: Remove extraneous rcu_torture_pipe_update_one() READ_ONCE() rcu: Allocate WQ with WQ_MEM_RECLAIM bit set rcu: Support direct wake-up of synchronize_rcu() users rcu: Add a trace event for synchronize_rcu_normal() rcu: Reduce synchronize_rcu() latency rcu: Fix buffer overflow in print_cpu_stall_info() rcu: Mollify sparse with RCU guard rcu-tasks: Fix show_rcu_tasks_trace_gp_kthread buffer overflow rcu-tasks: Fix the comments for tasks_rcu_exit_srcu_stall_timer rcu-tasks: Replace exit_tasks_rcu_start() initialization with WARN_ON_ONCE() rcu: Remove redundant CONFIG_PROVE_RCU #if condition ...
2024-05-08seccomp: Constify sysctl subhelpersKees Cook1-2/+2
The read_actions_logged() and write_actions_logged() helpers called by the sysctl proc handler seccomp_actions_logged_handler() are already expecting their sysctl table argument to be read-only. Actually mark the argument as const in preparation[1] for global constification of the sysctl tables. Suggested-by: Thomas Weißschuh <linux@weissschuh.net> Link: https://lore.kernel.org/lkml/20240423-sysctl-const-handler-v3-11-e0beccb836e2@weissschuh.net/ [1] Reviewed-by: Luis Chamberlain <mcgrof@kernel.org> Reviewed-by: Thomas Weißschuh <linux@weissschuh.net> Link: https://lore.kernel.org/r/20240508171337.work.861-kees@kernel.org Signed-off-by: Kees Cook <keescook@chromium.org>
2024-05-08timers/migration: Prevent out of bounds access on failureLevi Yun1-2/+2
When tmigr_setup_groups() fails the level 0 group allocation, then the cleanup derefences index -1 of the local stack array. Prevent this by checking the loop condition first. Fixes: 7ee988770326 ("timers: Implement the hierarchical pull model") Signed-off-by: Levi Yun <ppbuk5246@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Link: https://lore.kernel.org/r/20240506041059.86877-1-ppbuk5246@gmail.com
2024-05-07kcsan, compiler_types: Introduce __data_racy type qualifierMarco Elver1-0/+17
Based on the discussion at [1], it would be helpful to mark certain variables as explicitly "data racy", which would result in KCSAN not reporting data races involving any accesses on such variables. To do that, introduce the __data_racy type qualifier: struct foo { ... int __data_racy bar; ... }; In KCSAN-kernels, __data_racy turns into volatile, which KCSAN already treats specially by considering them "marked". In non-KCSAN kernels the type qualifier turns into no-op. The generated code between KCSAN-instrumented kernels and non-KCSAN kernels is already huge (inserted calls into runtime for every memory access), so the extra generated code (if any) due to volatile for few such __data_racy variables are unlikely to have measurable impact on performance. Link: https://lore.kernel.org/all/CAHk-=wi3iondeh_9V2g3Qz5oHTRjLsOpoy83hb58MVh=nRZe0A@mail.gmail.com/ [1] Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Marco Elver <elver@google.com> Cc: Paul E. McKenney <paulmck@kernel.org> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2024-05-05Merge tag 'irq-urgent-2024-05-05' of ↵Linus Torvalds1-4/+8
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq fix from Ingo Molnar: "Fix suspicious RCU usage in __do_softirq()" * tag 'irq-urgent-2024-05-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: softirq: Fix suspicious RCU usage in __do_softirq()
2024-05-05Merge tag 'probes-fixes-v6.9-rc6' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull probes fix from Masami Hiramatsu: - probe-events: Fix memory leak in parsing probe argument. There is a memory leak (forget to free an allocated buffer) in a memory allocation failure path. Fix it to jump to the correct error handling code. * tag 'probes-fixes-v6.9-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: tracing/probes: Fix memory leak in traceprobe_parse_probe_arg_body()
2024-05-05Merge tag 'trace-v6.9-rc6-2' of ↵Linus Torvalds1-0/+12
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing and tracefs fixes from Steven Rostedt: - Fix RCU callback of freeing an eventfs_inode. The freeing of the eventfs_inode from the kref going to zero freed the contents of the eventfs_inode and then used kfree_rcu() to free the inode itself. But the contents should also be protected by RCU. Switch to a call_rcu() that calls a function to free all of the eventfs_inode after the RCU synchronization. - The tracing subsystem maps its own descriptor to a file represented by eventfs. The freeing of this descriptor needs to know when the last reference of an eventfs_inode is released, but currently there is no interface for that. Add a "release" callback to the eventfs_inode entry array that allows for freeing of data that can be referenced by the eventfs_inode being opened. Then increment the ref counter for this descriptor when the eventfs_inode file is created, and decrement/free it when the last reference to the eventfs_inode is released and the file is removed. This prevents races between freeing the descriptor and the opening of the eventfs file. - Fix the permission processing of eventfs. The change to make the permissions of eventfs default to the mount point but keep track of when changes were made had a side effect that could cause security concerns. When the tracefs is remounted with a given gid or uid, all the files within it should inherit that gid or uid. But if the admin had changed the permission of some file within the tracefs file system, it would not get updated by the remount. This caused the kselftest of file permissions to fail the second time it is run. The first time, all changes would look fine, but the second time, because the changes were "saved", the remount did not reset them. Create a link list of all existing tracefs inodes, and clear the saved flags on them on a remount if the remount changes the corresponding gid or uid fields. This also simplifies the code by removing the distinction between the toplevel eventfs and an instance eventfs. They should both act the same. They were different because of a misconception due to the remount not resetting the flags. Now that remount resets all the files and directories to default to the root node if a uid/gid is specified, it makes the logic simpler to implement. * tag 'trace-v6.9-rc6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: eventfs: Have "events" directory get permissions from its parent eventfs: Do not treat events directory different than other directories eventfs: Do not differentiate the toplevel events directory tracefs: Still use mount point as default permissions for instances tracefs: Reset permissions on remount if permissions are options eventfs: Free all of the eventfs_inode after RCU eventfs/tracing: Add callback for release of an eventfs_inode
2024-05-05Merge tag 'dma-mapping-6.9-2024-05-04' of ↵Linus Torvalds1-0/+1
git://git.infradead.org/users/hch/dma-mapping Pull dma-mapping fix from Christoph Hellwig: - fix the combination of restricted pools and dynamic swiotlb (Will Deacon) * tag 'dma-mapping-6.9-2024-05-04' of git://git.infradead.org/users/hch/dma-mapping: swiotlb: initialise restricted pool list_head when SWIOTLB_DYNAMIC=y
2024-05-04eventfs/tracing: Add callback for release of an eventfs_inodeSteven Rostedt (Google)1-0/+12
Synthetic events create and destroy tracefs files when they are created and removed. The tracing subsystem has its own file descriptor representing the state of the events attached to the tracefs files. There's a race between the eventfs files and this file descriptor of the tracing system where the following can cause an issue: With two scripts 'A' and 'B' doing: Script 'A': echo "hello int aaa" > /sys/kernel/tracing/synthetic_events while : do echo 0 > /sys/kernel/tracing/events/synthetic/hello/enable done Script 'B': echo > /sys/kernel/tracing/synthetic_events Script 'A' creates a synthetic event "hello" and then just writes zero into its enable file. Script 'B' removes all synthetic events (including the newly created "hello" event). What happens is that the opening of the "enable" file has: { struct trace_event_file *file = inode->i_private; int ret; ret = tracing_check_open_get_tr(file->tr); [..] But deleting the events frees the "file" descriptor, and a "use after free" happens with the dereference at "file->tr". The file descriptor does have a reference counter, but there needs to be a way to decrement it from the eventfs when the eventfs_inode is removed that represents this file descriptor. Add an optional "release" callback to the eventfs_entry array structure, that gets called when the eventfs file is about to be removed. This allows for the creating on the eventfs file to increment the tracing file descriptor ref counter. When the eventfs file is deleted, it can call the release function that will call the put function for the tracing file descriptor. This will protect the tracing file from being freed while a eventfs file that references it is being opened. Link: https://lore.kernel.org/linux-trace-kernel/20240426073410.17154-1-Tze-nan.Wu@mediatek.com/ Link: https://lore.kernel.org/linux-trace-kernel/20240502090315.448cba46@gandalf.local.home Cc: stable@vger.kernel.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Fixes: 5790b1fb3d672 ("eventfs: Remove eventfs_file and just use eventfs_inode") Reported-by: Tze-nan wu <Tze-nan.Wu@mediatek.com> Tested-by: Tze-nan Wu (吳澤南) <Tze-nan.Wu@mediatek.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2024-05-03stackleak: Use a copy of the ctl_table argumentThomas Weißschuh1-3/+3
Sysctl handlers are not supposed to modify the ctl_table passed to them. Adapt the logic to work with a temporary variable, similar to how it is done in other parts of the kernel. This is also a prerequisite to enforce the immutability of the argument through the callbacks. Reviewed-by: Luis Chamberlain <mcgrof@kernel.org> Signed-off-by: Thomas Weißschuh <linux@weissschuh.net> Reviewed-by: Tycho Andersen <tycho@tycho.pizza> Link: https://lore.kernel.org/r/20240503-sysctl-const-stackleak-v1-1-603fecb19170@weissschuh.net Signed-off-by: Kees Cook <keescook@chromium.org>
2024-05-02Merge tag 'net-6.9-rc7' of ↵Linus Torvalds2-2/+40
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net Pull networking fixes from Paolo Abeni: "Including fixes from bpf. Relatively calm week, likely due to public holiday in most places. No known outstanding regressions. Current release - regressions: - rxrpc: fix wrong alignmask in __page_frag_alloc_align() - eth: e1000e: change usleep_range to udelay in PHY mdic access Previous releases - regressions: - gro: fix udp bad offset in socket lookup - bpf: fix incorrect runtime stat for arm64 - tipc: fix UAF in error path - netfs: fix a potential infinite loop in extract_user_to_sg() - eth: ice: ensure the copied buf is NUL terminated - eth: qeth: fix kernel panic after setting hsuid Previous releases - always broken: - bpf: - verifier: prevent userspace memory access - xdp: use flags field to disambiguate broadcast redirect - bridge: fix multicast-to-unicast with fraglist GSO - mptcp: ensure snd_nxt is properly initialized on connect - nsh: fix outer header access in nsh_gso_segment(). - eth: bcmgenet: fix racing registers access - eth: vxlan: fix stats counters. Misc: - a bunch of MAINTAINERS file updates" * tag 'net-6.9-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (45 commits) MAINTAINERS: mark MYRICOM MYRI-10G as Orphan MAINTAINERS: remove Ariel Elior net: gro: add flush check in udp_gro_receive_segment net: gro: fix udp bad offset in socket lookup by adding {inner_}network_offset to napi_gro_cb ipv4: Fix uninit-value access in __ip_make_skb() s390/qeth: Fix kernel panic after setting hsuid vxlan: Pull inner IP header in vxlan_rcv(). tipc: fix a possible memleak in tipc_buf_append tipc: fix UAF in error path rxrpc: Clients must accept conn from any address net: core: reject skb_copy(_expand) for fraglist GSO skbs net: bridge: fix multicast-to-unicast with fraglist GSO mptcp: ensure snd_nxt is properly initialized on connect e1000e: change usleep_range to udelay in PHY mdic access net: dsa: mv88e6xxx: Fix number of databases for 88E6141 / 88E6341 cxgb4: Properly lock TX queue for the selftest. rxrpc: Fix using alignmask being zero for __page_frag_alloc_align() vxlan: Add missing VNI filter counter update in arp_reduce(). vxlan: Fix racy device stats updates. net: qede: use return from qede_parse_actions() ...
2024-05-02swiotlb: initialise restricted pool list_head when SWIOTLB_DYNAMIC=yWill Deacon1-0/+1
Using restricted DMA pools (CONFIG_DMA_RESTRICTED_POOL=y) in conjunction with dynamic SWIOTLB (CONFIG_SWIOTLB_DYNAMIC=y) leads to the following crash when initialising the restricted pools at boot-time: | Unable to handle kernel NULL pointer dereference at virtual address 0000000000000008 | Internal error: Oops: 0000000096000005 [#1] PREEMPT SMP | pc : rmem_swiotlb_device_init+0xfc/0x1ec | lr : rmem_swiotlb_device_init+0xf0/0x1ec | Call trace: | rmem_swiotlb_device_init+0xfc/0x1ec | of_reserved_mem_device_init_by_idx+0x18c/0x238 | of_dma_configure_id+0x31c/0x33c | platform_dma_configure+0x34/0x80 faddr2line reveals that the crash is in the list validation code: include/linux/list.h:83 include/linux/rculist.h:79 include/linux/rculist.h:106 kernel/dma/swiotlb.c:306 kernel/dma/swiotlb.c:1695 because add_mem_pool() is trying to list_add_rcu() to a NULL 'mem->pools'. Fix the crash by initialising the 'mem->pools' list_head in rmem_swiotlb_device_init() before calling add_mem_pool(). Reported-by: Nikita Ioffe <ioffe@google.com> Tested-by: Nikita Ioffe <ioffe@google.com> Fixes: 1aaa736815eb ("swiotlb: allocate a new memory pool when existing pools are full") Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Christoph Hellwig <hch@lst.de>
2024-05-01hardening: Enable KCFI and some other optionsKees Cook1-0/+8
Add some stuff that got missed along the way: - CONFIG_UNWIND_PATCH_PAC_INTO_SCS=y so SCS vs PAC is hardware selectable. - CONFIG_X86_KERNEL_IBT=y while a default, just be sure. - CONFIG_CFI_CLANG=y globally. - CONFIG_PAGE_TABLE_CHECK=y for userspace mapping sanity. Reviewed-by: Nathan Chancellor <nathan@kernel.org> Link: https://lore.kernel.org/r/20240501193709.make.982-kees@kernel.org Signed-off-by: Kees Cook <keescook@chromium.org>
2024-05-01Merge branches 'fixes.2024.04.15a', 'misc.2024.04.12a', ↵Uladzislau Rezki (Sony)12-77/+479
'rcu-sync-normal-improve.2024.04.15a', 'rcu-tasks.2024.04.15a' and 'rcutorture.2024.04.15a' into rcu-merge.2024.04.15a fixes.2024.04.15a: RCU fixes misc.2024.04.12a: Miscellaneous fixes rcu-sync-normal-improve.2024.04.15a: Improving synchronize_rcu() call rcu-tasks.2024.04.15a: Tasks RCU updates rcutorture.2024.04.15a: Torture-test updates
2024-04-30Merge tag 'wq-for-6.9-rc6-fixes' of ↵Linus Torvalds1-3/+16
git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq Pull workqueue fixes from Tejun Heo: "Two doc update patches and the following three fixes: - On single node systems, the default pool is used but the node_nr_active for the default pool was set to min_active. This effectively limited the max concurrency of unbound pools on single node systems to 8 causing performance regressions on some workloads. Fixed by setting the default pool's node_nr_active to max_active. - wq_update_node_max_active() could trigger divide-by-zero if the intersection between the allowed CPUs for an unbound workqueue and online CPUs becomes empty. - When kick_pool() was trying to repatriate a worker to a CPU in its pod by setting task->wake_cpu, it didn't consider whether the CPU being selected is online or not which obviously can lead to subobtimal behaviors. On s390, this triggered a crash in arch code. The workqueue patch removes the gross misbehavior but doesn't fix the crash completely as there's a race window in which CPUs can go down after wake_cpu is set. Need to decide whether the fix should be on the core or arch side" * tag 'wq-for-6.9-rc6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: workqueue: Fix divide error in wq_update_node_max_active() workqueue: The default node_nr_active should have its max set to max_active workqueue: Fix selection of wake_cpu in kick_pool() docs/zh_CN: core-api: Update translation of workqueue.rst to 6.9-rc1 Documentation/core-api: Update events_freezable_power references.
2024-04-29bounds: Use the right number of bits for power-of-two CONFIG_NR_CPUSMatthew Wilcox (Oracle)1-1/+1
bits_per() rounds up to the next power of two when passed a power of two. This causes crashes on some machines and configurations. Reported-by: Михаил Новоселов <m.novosyolov@rosalinux.ru> Tested-by: Ильфат Гаптрахманов <i.gaptrakhmanov@rosalinux.ru> Link: https://gitlab.freedesktop.org/drm/amd/-/issues/3347 Link: https://lore.kernel.org/all/1c978cf1-2934-4e66-e4b3-e81b04cb3571@rosalinux.ru/ Fixes: f2d5dcb48f7b (bounds: support non-power-of-two CONFIG_NR_CPUS) Cc: <stable@vger.kernel.org> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Rik van Riel <riel@surriel.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2024-04-29tracing/probes: Fix memory leak in traceprobe_parse_probe_arg_body()LuMingYin1-1/+1
If traceprobe_parse_probe_arg_body() failed to allocate 'parg->fmt', it jumps to the label 'out' instead of 'fail' by mistake.In the result, the buffer 'tmp' is not freed in this case and leaks its memory. Thus jump to the label 'fail' in that error case. Link: https://lore.kernel.org/all/20240427072347.1421053-1-lumingyindetect@126.com/ Fixes: 032330abd08b ("tracing/probes: Cleanup probe argument parser") Signed-off-by: LuMingYin <lumingyindetect@126.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2024-04-29softirq: Fix suspicious RCU usage in __do_softirq()Zqiang1-4/+8
Currently, the condition "__this_cpu_read(ksoftirqd) == current" is used to invoke rcu_softirq_qs() in ksoftirqd tasks context for non-RT kernels. This works correctly as long as the context is actually task context but this condition is wrong when: - the current task is ksoftirqd - the task is interrupted in a RCU read side critical section - __do_softirq() is invoked on return from interrupt Syzkaller triggered the following scenario: -> finish_task_switch() -> put_task_struct_rcu_user() -> call_rcu(&task->rcu, delayed_put_task_struct) -> __kasan_record_aux_stack() -> pfn_valid() -> rcu_read_lock_sched() <interrupt> __irq_exit_rcu() -> __do_softirq)() -> if (!IS_ENABLED(CONFIG_PREEMPT_RT) && __this_cpu_read(ksoftirqd) == current) -> rcu_softirq_qs() -> RCU_LOCKDEP_WARN(lock_is_held(&rcu_sched_lock_map)) The rcu quiescent state is reported in the rcu-read critical section, so the lockdep warning is triggered. Fix this by splitting out the inner working of __do_softirq() into a helper function which takes an argument to distinguish between ksoftirqd task context and interrupted context and invoke it from the relevant call sites with the proper context information and use that for the conditional invocation of rcu_softirq_qs(). Reported-by: syzbot+dce04ed6d1438ad69656@syzkaller.appspotmail.com Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Zqiang <qiang.zhang1211@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20240427102808.29356-1-qiang.zhang1211@gmail.com Link: https://lore.kernel.org/lkml/8f281a10-b85a-4586-9586-5bbc12dc784f@paulmck-laptop/T/#mea8aba4abfcb97bbf499d169ce7f30c4cff1b0e3
2024-04-28Merge tag 'sched-urgent-2024-04-28' of ↵Linus Torvalds2-16/+36
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler fixes from Ingo Molnar: - Fix EEVDF corner cases - Fix two nohz_full= related bugs that can cause boot crashes and warnings * tag 'sched-urgent-2024-04-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/isolation: Fix boot crash when maxcpus < first housekeeping CPU sched/isolation: Prevent boot crash when the boot CPU is nohz_full sched/eevdf: Prevent vlag from going out of bounds in reweight_eevdf() sched/eevdf: Fix miscalculation in reweight_entity() when se is not curr sched/eevdf: Always update V if se->on_rq when reweighting
2024-04-28Merge tag 'x86-urgent-2024-04-28' of ↵Linus Torvalds1-4/+10
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Ingo Molnar: - Make the CPU_MITIGATIONS=n interaction with conflicting mitigation-enabling boot parameters a bit saner. - Re-enable CPU mitigations by default on non-x86 - Fix TDX shared bit propagation on mprotect() - Fix potential show_regs() system hang when PKE initialization is not fully finished yet. - Add the 0x10-0x1f model IDs to the Zen5 range - Harden #VC instruction emulation some more * tag 'x86-urgent-2024-04-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: cpu: Ignore "mitigations" kernel parameter if CPU_MITIGATIONS=n cpu: Re-enable CPU mitigations by default for !X86 architectures x86/tdx: Preserve shared bit on mprotect() x86/cpu: Fix check for RDPKRU in __show_regs() x86/CPU/AMD: Add models 0x10-0x1f to the Zen5 range x86/sev: Check for MWAITX and MONITORX opcodes in the #VC handler
2024-04-28sched/isolation: Fix boot crash when maxcpus < first housekeeping CPUOleg Nesterov1-1/+6
housekeeping_setup() checks cpumask_intersects(present, online) to ensure that the kernel will have at least one housekeeping CPU after smp_init(), but this doesn't work if the maxcpus= kernel parameter limits the number of processors available after bootup. For example, a kernel with "maxcpus=2 nohz_full=0-2" parameters crashes at boot time on a virtual machine with 4 CPUs. Change housekeeping_setup() to use cpumask_first_and() and check that the returned CPU number is valid and less than setup_max_cpus. Another corner case is "nohz_full=0" on a machine with a single CPU or with the maxcpus=1 kernel argument. In this case non_housekeeping_mask is empty and tick_nohz_full_setup() makes no sense. And indeed, the kernel hits the WARN_ON(tick_nohz_full_running) in tick_sched_do_timer(). And how should the kernel interpret the "nohz_full=" parameter? It should be silently ignored, but currently cpulist_parse() happily returns the empty cpumask and this leads to the same problem. Change housekeeping_setup() to check cpumask_empty(non_housekeeping_mask) and do nothing in this case. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Phil Auld <pauld@redhat.com> Acked-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20240413141746.GA10008@redhat.com
2024-04-28sched/isolation: Prevent boot crash when the boot CPU is nohz_fullOleg Nesterov1-1/+10
Documentation/timers/no_hz.rst states that the "nohz_full=" mask must not include the boot CPU, which is no longer true after: 08ae95f4fd3b ("nohz_full: Allow the boot CPU to be nohz_full"). However after: aae17ebb53cd ("workqueue: Avoid using isolated cpus' timers on queue_delayed_work") the kernel will crash at boot time in this case; housekeeping_any_cpu() returns an invalid CPU number until smp_init() brings the first housekeeping CPU up. Change housekeeping_any_cpu() to check the result of cpumask_any_and() and return smp_processor_id() in this case. This is just the simple and backportable workaround which fixes the symptom, but smp_processor_id() at boot time should be safe at least for type == HK_TYPE_TIMER, this more or less matches the tick_do_timer_boot_cpu logic. There is no worry about cpu_down(); tick_nohz_cpu_down() will not allow to offline tick_do_timer_cpu (the 1st online housekeeping CPU). Fixes: aae17ebb53cd ("workqueue: Avoid using isolated cpus' timers on queue_delayed_work") Reported-by: Chris von Recklinghausen <crecklin@redhat.com> Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Phil Auld <pauld@redhat.com> Acked-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20240411143905.GA19288@redhat.com Closes: https://lore.kernel.org/all/20240402105847.GA24832@redhat.com/
2024-04-27profiling: Remove create_prof_cpu_mask().Tetsuo Handa1-43/+0
create_prof_cpu_mask() is no longer used after commit 1f44a225777e ("s390: convert interrupt handling to use generic hardirq"). Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2024-04-27Merge tag 'for-netdev' of ↵Jakub Kicinski2-2/+40
https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf Daniel Borkmann says: ==================== pull-request: bpf 2024-04-26 We've added 12 non-merge commits during the last 22 day(s) which contain a total of 14 files changed, 168 insertions(+), 72 deletions(-). The main changes are: 1) Fix BPF_PROBE_MEM in verifier and JIT to skip loads from vsyscall page, from Puranjay Mohan. 2) Fix a crash in XDP with devmap broadcast redirect when the latter map is in process of being torn down, from Toke Høiland-Jørgensen. 3) Fix arm64 and riscv64 BPF JITs to properly clear start time for BPF program runtime stats, from Xu Kuohai. 4) Fix a sockmap KCSAN-reported data race in sk_psock_skb_ingress_enqueue, from Jason Xing. 5) Fix BPF verifier error message in resolve_pseudo_ldimm64, from Anton Protopopov. 6) Fix missing DEBUG_INFO_BTF_MODULES Kconfig menu item, from Andrii Nakryiko. * tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf: selftests/bpf: Test PROBE_MEM of VSYSCALL_ADDR on x86-64 bpf, x86: Fix PROBE_MEM runtime load check bpf: verifier: prevent userspace memory access xdp: use flags field to disambiguate broadcast redirect arm32, bpf: Reimplement sign-extension mov instruction riscv, bpf: Fix incorrect runtime stats bpf, arm64: Fix incorrect runtime stats bpf: Fix a verifier verbose message bpf, skmsg: Fix NULL pointer dereference in sk_psock_skb_ingress_enqueue MAINTAINERS: bpf: Add Lehui and Puranjay as riscv64 reviewers MAINTAINERS: Update email address for Puranjay Mohan bpf, kconfig: Fix DEBUG_INFO_BTF_MODULES Kconfig definition ==================== Link: https://lore.kernel.org/r/20240426224248.26197-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-26Merge tag 'mm-hotfixes-stable-2024-04-26-13-30' of ↵Linus Torvalds1-3/+2
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull misc fixes from Andrew Morton: "11 hotfixes. 8 are cc:stable and the remaining 3 (nice ratio!) address post-6.8 issues or aren't considered suitable for backporting. All except one of these are for MM. I see no particular theme - it's singletons all over" * tag 'mm-hotfixes-stable-2024-04-26-13-30' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: mm/hugetlb: fix DEBUG_LOCKS_WARN_ON(1) when dissolve_free_hugetlb_folio() selftests: mm: protection_keys: save/restore nr_hugepages value from launch script stackdepot: respect __GFP_NOLOCKDEP allocation flag hugetlb: check for anon_vma prior to folio allocation mm: zswap: fix shrinker NULL crash with cgroup_disable=memory mm: turn folio_test_hugetlb into a PageType mm: support page_mapcount() on page_has_type() pages mm: create FOLIO_FLAG_FALSE and FOLIO_TYPE_OPS macros mm/hugetlb: fix missing hugetlb_lock for resv uncharge selftests: mm: fix unused and uninitialized variable warning selftests/harness: remove use of LINE_MAX
2024-04-26bpf: verifier: prevent userspace memory accessPuranjay Mohan2-0/+39
With BPF_PROBE_MEM, BPF allows de-referencing an untrusted pointer. To thwart invalid memory accesses, the JITs add an exception table entry for all such accesses. But in case the src_reg + offset is a userspace address, the BPF program might read that memory if the user has mapped it. Make the verifier add guard instructions around such memory accesses and skip the load if the address falls into the userspace region. The JITs need to implement bpf_arch_uaddress_limit() to define where the userspace addresses end for that architecture or TASK_SIZE is taken as default. The implementation is as follows: REG_AX = SRC_REG if(offset) REG_AX += offset; REG_AX >>= 32; if (REG_AX <= (uaddress_limit >> 32)) DST_REG = 0; else DST_REG = *(size *)(SRC_REG + offset); Comparing just the upper 32 bits of the load address with the upper 32 bits of uaddress_limit implies that the values are being aligned down to a 4GB boundary before comparison. The above means that all loads with address <= uaddress_limit + 4GB are skipped. This is acceptable because there is a large hole (much larger than 4GB) between userspace and kernel space memory, therefore a correctly functioning BPF program should not access this 4GB memory above the userspace. Let's analyze what this patch does to the following fentry program dereferencing an untrusted pointer: SEC("fentry/tcp_v4_connect") int BPF_PROG(fentry_tcp_v4_connect, struct sock *sk) { *(volatile long *)sk; return 0; } BPF Program before | BPF Program after ------------------ | ----------------- 0: (79) r1 = *(u64 *)(r1 +0) 0: (79) r1 = *(u64 *)(r1 +0) ----------------------------------------------------------------------- 1: (79) r1 = *(u64 *)(r1 +0) --\ 1: (bf) r11 = r1 ----------------------------\ \ 2: (77) r11 >>= 32 2: (b7) r0 = 0 \ \ 3: (b5) if r11 <= 0x8000 goto pc+2 3: (95) exit \ \-> 4: (79) r1 = *(u64 *)(r1 +0) \ 5: (05) goto pc+1 \ 6: (b7) r1 = 0 \-------------------------------------- 7: (b7) r0 = 0 8: (95) exit As you can see from above, in the best case (off=0), 5 extra instructions are emitted. Now, we analyze the same program after it has gone through the JITs of ARM64 and RISC-V architectures. We follow the single load instruction that has the untrusted pointer and see what instrumentation has been added around it. x86-64 JIT ========== JIT's Instrumentation (upstream) --------------------- 0: nopl 0x0(%rax,%rax,1) 5: xchg %ax,%ax 7: push %rbp 8: mov %rsp,%rbp b: mov 0x0(%rdi),%rdi --------------------------------- f: movabs $0x800000000000,%r11 19: cmp %r11,%rdi 1c: jb 0x000000000000002a 1e: mov %rdi,%r11 21: add $0x0,%r11 28: jae 0x000000000000002e 2a: xor %edi,%edi 2c: jmp 0x0000000000000032 2e: mov 0x0(%rdi),%rdi --------------------------------- 32: xor %eax,%eax 34: leave 35: ret The x86-64 JIT already emits some instructions to protect against user memory access. This patch doesn't make any changes for the x86-64 JIT. ARM64 JIT ========= No Intrumentation Verifier's Instrumentation (upstream) (This patch) ----------------- -------------------------- 0: add x9, x30, #0x0 0: add x9, x30, #0x0 4: nop 4: nop 8: paciasp 8: paciasp c: stp x29, x30, [sp, #-16]! c: stp x29, x30, [sp, #-16]! 10: mov x29, sp 10: mov x29, sp 14: stp x19, x20, [sp, #-16]! 14: stp x19, x20, [sp, #-16]! 18: stp x21, x22, [sp, #-16]! 18: stp x21, x22, [sp, #-16]! 1c: stp x25, x26, [sp, #-16]! 1c: stp x25, x26, [sp, #-16]! 20: stp x27, x28, [sp, #-16]! 20: stp x27, x28, [sp, #-16]! 24: mov x25, sp 24: mov x25, sp 28: mov x26, #0x0 28: mov x26, #0x0 2c: sub x27, x25, #0x0 2c: sub x27, x25, #0x0 30: sub sp, sp, #0x0 30: sub sp, sp, #0x0 34: ldr x0, [x0] 34: ldr x0, [x0] -------------------------------------------------------------------------------- 38: ldr x0, [x0] ----------\ 38: add x9, x0, #0x0 -----------------------------------\\ 3c: lsr x9, x9, #32 3c: mov x7, #0x0 \\ 40: cmp x9, #0x10, lsl #12 40: mov sp, sp \\ 44: b.ls 0x0000000000000050 44: ldp x27, x28, [sp], #16 \\--> 48: ldr x0, [x0] 48: ldp x25, x26, [sp], #16 \ 4c: b 0x0000000000000054 4c: ldp x21, x22, [sp], #16 \ 50: mov x0, #0x0 50: ldp x19, x20, [sp], #16 \--------------------------------------- 54: ldp x29, x30, [sp], #16 54: mov x7, #0x0 58: add x0, x7, #0x0 58: mov sp, sp 5c: autiasp 5c: ldp x27, x28, [sp], #16 60: ret 60: ldp x25, x26, [sp], #16 64: nop 64: ldp x21, x22, [sp], #16 68: ldr x10, 0x0000000000000070 68: ldp x19, x20, [sp], #16 6c: br x10 6c: ldp x29, x30, [sp], #16 70: add x0, x7, #0x0 74: autiasp 78: ret 7c: nop 80: ldr x10, 0x0000000000000088 84: br x10 There are 6 extra instructions added in ARM64 in the best case. This will become 7 in the worst case (off != 0). RISC-V JIT (RISCV_ISA_C Disabled) ========== No Intrumentation Verifier's Instrumentation (upstream) (This patch) ----------------- -------------------------- 0: nop 0: nop 4: nop 4: nop 8: li a6, 33 8: li a6, 33 c: addi sp, sp, -16 c: addi sp, sp, -16 10: sd s0, 8(sp) 10: sd s0, 8(sp) 14: addi s0, sp, 16 14: addi s0, sp, 16 18: ld a0, 0(a0) 18: ld a0, 0(a0) --------------------------------------------------------------- 1c: ld a0, 0(a0) --\ 1c: mv t0, a0 --------------------------\ \ 20: srli t0, t0, 32 20: li a5, 0 \ \ 24: lui t1, 4096 24: ld s0, 8(sp) \ \ 28: sext.w t1, t1 28: addi sp, sp, 16 \ \ 2c: bgeu t1, t0, 12 2c: sext.w a0, a5 \ \--> 30: ld a0, 0(a0) 30: ret \ 34: j 8 \ 38: li a0, 0 \------------------------------ 3c: li a5, 0 40: ld s0, 8(sp) 44: addi sp, sp, 16 48: sext.w a0, a5 4c: ret There are 7 extra instructions added in RISC-V. Fixes: 800834285361 ("bpf, arm64: Add BPF exception tables") Reported-by: Breno Leitao <leitao@debian.org> Suggested-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Ilya Leoshkevich <iii@linux.ibm.com> Signed-off-by: Puranjay Mohan <puranjay12@gmail.com> Link: https://lore.kernel.org/r/20240424100210.11982-2-puranjay@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-04-25cpu: Ignore "mitigations" kernel parameter if CPU_MITIGATIONS=nSean Christopherson1-4/+10
Explicitly disallow enabling mitigations at runtime for kernels that were built with CONFIG_CPU_MITIGATIONS=n, as some architectures may omit code entirely if mitigations are disabled at compile time. E.g. on x86, a large pile of Kconfigs are buried behind CPU_MITIGATIONS, and trying to provide sane behavior for retroactively enabling mitigations is extremely difficult, bordering on impossible. E.g. page table isolation and call depth tracking require build-time support, BHI mitigations will still be off without additional kernel parameters, etc. [ bp: Touchups. ] Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Acked-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20240420000556.2645001-3-seanjc@google.com
2024-04-25cpu: Re-enable CPU mitigations by default for !X86 architecturesSean Christopherson1-2/+2
Rename x86's to CPU_MITIGATIONS, define it in generic code, and force it on for all architectures exception x86. A recent commit to turn mitigations off by default if SPECULATION_MITIGATIONS=n kinda sorta missed that "cpu_mitigations" is completely generic, whereas SPECULATION_MITIGATIONS is x86-specific. Rename x86's SPECULATIVE_MITIGATIONS instead of keeping both and have it select CPU_MITIGATIONS, as having two configs for the same thing is unnecessary and confusing. This will also allow x86 to use the knob to manage mitigations that aren't strictly related to speculative execution. Use another Kconfig to communicate to common code that CPU_MITIGATIONS is already defined instead of having x86's menu depend on the common CPU_MITIGATIONS. This allows keeping a single point of contact for all of x86's mitigations, and it's not clear that other architectures *want* to allow disabling mitigations at compile-time. Fixes: f337a6a21e2f ("x86/cpu: Actually turn off mitigations by default for SPECULATION_MITIGATIONS=n") Closes: https://lkml.kernel.org/r/20240413115324.53303a68%40canb.auug.org.au Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Reported-by: Michael Ellerman <mpe@ellerman.id.au> Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Acked-by: Borislav Petkov (AMD) <bp@alien8.de> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20240420000556.2645001-2-seanjc@google.com
2024-04-25mm: turn folio_test_hugetlb into a PageTypeMatthew Wilcox (Oracle)1-3/+2
The current folio_test_hugetlb() can be fooled by a concurrent folio split into returning true for a folio which has never belonged to hugetlbfs. This can't happen if the caller holds a refcount on it, but we have a few places (memory-failure, compaction, procfs) which do not and should not take a speculative reference. Since hugetlb pages do not use individual page mapcounts (they are always fully mapped and use the entire_mapcount field to record the number of mappings), the PageType field is available now that page_mapcount() ignores the value in this field. In compaction and with CONFIG_DEBUG_VM enabled, the current implementation can result in an oops, as reported by Luis. This happens since 9c5ccf2db04b ("mm: remove HUGETLB_PAGE_DTOR") effectively added some VM_BUG_ON() checks in the PageHuge() testing path. [willy@infradead.org: update vmcoreinfo] Link: https://lkml.kernel.org/r/ZgGZUvsdhaT1Va-T@casper.infradead.org Link: https://lkml.kernel.org/r/20240321142448.1645400-6-willy@infradead.org Fixes: 9c5ccf2db04b ("mm: remove HUGETLB_PAGE_DTOR") Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: David Hildenbrand <david@redhat.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Reported-by: Luis Chamberlain <mcgrof@kernel.org> Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218227 Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Oscar Salvador <osalvador@suse.de> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-04-24workqueue: Fix divide error in wq_update_node_max_active()Lai Jiangshan1-0/+9
Yue Sun and xingwei lee reported a divide error bug in wq_update_node_max_active(): divide error: 0000 [#1] PREEMPT SMP KASAN PTI CPU: 1 PID: 21 Comm: cpuhp/1 Not tainted 6.9.0-rc5 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 RIP: 0010:wq_update_node_max_active+0x369/0x6b0 kernel/workqueue.c:1605 Code: 24 bf 00 00 00 80 44 89 fe e8 83 27 33 00 41 83 fc ff 75 0d 41 81 ff 00 00 00 80 0f 84 68 01 00 00 e8 fb 22 33 00 44 89 f8 99 <41> f7 fc 89 c5 89 c7 44 89 ee e8 a8 24 33 00 89 ef 8b 5c 24 04 89 RSP: 0018:ffffc9000018fbb0 EFLAGS: 00010293 RAX: 00000000000000ff RBX: 0000000000000001 RCX: ffff888100ada500 RDX: 0000000000000000 RSI: 00000000000000ff RDI: 0000000080000000 RBP: 0000000000000001 R08: ffffffff815b1fcd R09: 1ffff1100364ad72 R10: dffffc0000000000 R11: ffffed100364ad73 R12: 0000000000000000 R13: 0000000000000100 R14: 0000000000000000 R15: 00000000000000ff FS: 0000000000000000(0000) GS:ffff888135c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fb8c06ca6f8 CR3: 000000010d6c6000 CR4: 0000000000750ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: <TASK> workqueue_offline_cpu+0x56f/0x600 kernel/workqueue.c:6525 cpuhp_invoke_callback+0x4e1/0x870 kernel/cpu.c:194 cpuhp_thread_fun+0x411/0x7d0 kernel/cpu.c:1092 smpboot_thread_fn+0x544/0xa10 kernel/smpboot.c:164 kthread+0x2ed/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:244 </TASK> Modules linked in: ---[ end trace 0000000000000000 ]--- After analysis, it happens when all of the CPUs in a workqueue's affinity get offine. The problem can be easily reproduced by: # echo 8 > /sys/devices/virtual/workqueue/<any-wq-name>/cpumask # echo 0 > /sys/devices/system/cpu/cpu3/online Use the default max_actives for nodes when all of the CPUs in the workqueue's affinity get offline to fix the problem. Reported-by: Yue Sun <samsun1006219@gmail.com> Reported-by: xingwei lee <xrivendell7@gmail.com> Link: https://lore.kernel.org/lkml/CAEkJfYPGS1_4JqvpSo0=FM0S1ytB8CEbyreLTtWpR900dUZymw@mail.gmail.com/ Fixes: 5797b1c18919 ("workqueue: Implement system-wide nr_active enforcement for unbound workqueues") Cc: stable@vger.kernel.org Signed-off-by: Lai Jiangshan <jiangshan.ljs@antgroup.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2024-04-24sched/pelt: Remove shift of thermal clockVincent Guittot3-27/+3
The optional shift of the clock used by thermal/hw load avg has been introduced to handle case where the signal was not always a high frequency hw signal. Now that cpufreq provides a signal for firmware and SW pressure, we can remove this exception and always keep this PELT signal aligned with other signals. Mark sysctl_sched_migration_cost boot parameter as deprecated Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Tested-by: Lukasz Luba <lukasz.luba@arm.com> Reviewed-by: Qais Yousef <qyousef@layalina.io> Reviewed-by: Lukasz Luba <lukasz.luba@arm.com> Link: https://lore.kernel.org/r/20240326091616.3696851-6-vincent.guittot@linaro.org
2024-04-24sched/cpufreq: Rename arch_update_thermal_pressure() => ↵Vincent Guittot5-34/+34
arch_update_hw_pressure() Now that cpufreq provides a pressure value to the scheduler, rename arch_update_thermal_pressure into HW pressure to reflect that it returns a pressure applied by HW (i.e. with a high frequency change) and not always related to thermal mitigation but also generated by max current limitation as an example. Such high frequency signal needs filtering to be smoothed and provide an value that reflects the average available capacity into the scheduler time scale. Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Tested-by: Lukasz Luba <lukasz.luba@arm.com> Reviewed-by: Qais Yousef <qyousef@layalina.io> Reviewed-by: Lukasz Luba <lukasz.luba@arm.com> Link: https://lore.kernel.org/r/20240326091616.3696851-5-vincent.guittot@linaro.org
2024-04-24sched/cpufreq: Take cpufreq feedback into accountVincent Guittot1-20/+25
Aggregate the different pressures applied on the capacity of CPUs and create a new function that returns the actual capacity of the CPU: get_actual_cpu_capacity(). Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Tested-by: Lukasz Luba <lukasz.luba@arm.com> Reviewed-by: Lukasz Luba <lukasz.luba@arm.com> Reviewed-by: Qais Yousef <qyousef@layalina.io> Link: https://lore.kernel.org/r/20240326091616.3696851-3-vincent.guittot@linaro.org
2024-04-24sched/fair: Fix update of rd->sg_overutilizedVincent Guittot1-1/+1
sg_overloaded is used instead of sg_overutilized to update rd->sg_overutilized. Fixes: 4475cd8bfd9b ("sched/balancing: Simplify the sg_status bitmask and use separate ->overloaded and ->overutilized flags") Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20240404155738.2866102-1-vincent.guittot@linaro.org
2024-04-24workqueue: The default node_nr_active should have its max set to max_activeTejun Heo1-1/+1
The default nna (node_nr_active) is used when the pool isn't tied to a specific NUMA node. This can happen in the following cases: 1. On NUMA, if per-node pwq init failure and the fallback pwq is used. 2. On NUMA, if a pool is configured to span multiple nodes. 3. On single node setups. 5797b1c18919 ("workqueue: Implement system-wide nr_active enforcement for unbound workqueues") set the default nna->max to min_active because only #1 was being considered. For #2 and #3, using min_active means that the max concurrency in normal operation is pushed down to min_active which is currently 8, which can obviously lead to performance issues. exact value nna->max is set to doesn't really matter. #2 can only happen if the workqueue is intentionally configured to ignore NUMA boundaries and there's no good way to distribute max_active in this case. #3 is the default behavior on single node machines. Let's set it the default nna->max to max_active. This fixes the artificially lowered concurrency problem on single node machines and shouldn't hurt anything for other cases. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Shinichiro Kawasaki <shinichiro.kawasaki@wdc.com> Fixes: 5797b1c18919 ("workqueue: Implement system-wide nr_active enforcement for unbound workqueues") Link: https://lore.kernel.org/dm-devel/20240410084531.2134621-1-shinichiro.kawasaki@wdc.com/ Signed-off-by: Tejun Heo <tj@kernel.org>
2024-04-23workqueue: Fix selection of wake_cpu in kick_pool()Sven Schnelle1-2/+6
With cpu_possible_mask=0-63 and cpu_online_mask=0-7 the following kernel oops was observed: smp: Bringing up secondary CPUs ... smp: Brought up 1 node, 8 CPUs Unable to handle kernel pointer dereference in virtual kernel address space Failing address: 0000000000000000 TEID: 0000000000000803 [..] Call Trace: arch_vcpu_is_preempted+0x12/0x80 select_idle_sibling+0x42/0x560 select_task_rq_fair+0x29a/0x3b0 try_to_wake_up+0x38e/0x6e0 kick_pool+0xa4/0x198 __queue_work.part.0+0x2bc/0x3a8 call_timer_fn+0x36/0x160 __run_timers+0x1e2/0x328 __run_timer_base+0x5a/0x88 run_timer_softirq+0x40/0x78 __do_softirq+0x118/0x388 irq_exit_rcu+0xc0/0xd8 do_ext_irq+0xae/0x168 ext_int_handler+0xbe/0xf0 psw_idle_exit+0x0/0xc default_idle_call+0x3c/0x110 do_idle+0xd4/0x158 cpu_startup_entry+0x40/0x48 rest_init+0xc6/0xc8 start_kernel+0x3c4/0x5e0 startup_continue+0x3c/0x50 The crash is caused by calling arch_vcpu_is_preempted() for an offline CPU. To avoid this, select the cpu with cpumask_any_and_distribute() to mask __pod_cpumask with cpu_online_mask. In case no cpu is left in the pool, skip the assignment. tj: This doesn't fully fix the bug as CPUs can still go down between picking the target CPU and the wake call. Fixing that likely requires adding cpu_online() test to either the sched or s390 arch code. However, regardless of how that is fixed, workqueue shouldn't be picking a CPU which isn't online as that would result in unpredictable and worse behavior. Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Fixes: 8639ecebc9b1 ("workqueue: Implement non-strict affinity scope for unbound workqueues") Cc: stable@vger.kernel.org # v6.6+ Signed-off-by: Tejun Heo <tj@kernel.org>
2024-04-22sched/eevdf: Prevent vlag from going out of bounds in reweight_eevdf()Xuewen Yan1-6/+12
It was possible to have pick_eevdf() return NULL, which then causes a NULL-deref. This turned out to be due to entity_eligible() returning falsely negative because of a s64 multiplcation overflow. Specifically, reweight_eevdf() computes the vlag without considering the limit placed upon vlag as update_entity_lag() does, and then the scaling multiplication (remember that weight is 20bit fixed point) can overflow. This then leads to the new vruntime being weird which then causes the above entity_eligible() to go side-ways and claim nothing is eligible. Thus limit the range of vlag accordingly. All this was quite rare, but fatal when it does happen. Closes: https://lore.kernel.org/all/ZhuYyrh3mweP_Kd8@nz.home/ Closes: https://lore.kernel.org/all/CA+9S74ih+45M_2TPUY_mPPVDhNvyYfy1J1ftSix+KjiTVxg8nw@mail.gmail.com/ Closes: https://lore.kernel.org/lkml/202401301012.2ed95df0-oliver.sang@intel.com/ Fixes: eab03c23c2a1 ("sched/eevdf: Fix vruntime adjustment on reweight") Reported-by: Sergei Trofimovich <slyich@gmail.com> Reported-by: Igor Raits <igor@gooddata.com> Reported-by: Breno Leitao <leitao@debian.org> Reported-by: kernel test robot <oliver.sang@intel.com> Reported-by: Yujie Liu <yujie.liu@intel.com> Signed-off-by: Xuewen Yan <xuewen.yan@unisoc.com> Reviewed-and-tested-by: Chen Yu <yu.c.chen@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20240422082238.5784-1-xuewen.yan@unisoc.com
2024-04-22sched/eevdf: Fix miscalculation in reweight_entity() when se is not currTianchen Ding1-5/+6
reweight_eevdf() only keeps V unchanged inside itself. When se != cfs_rq->curr, it would be dequeued from rb tree first. So that V is changed and the result is wrong. Pass the original V to reweight_eevdf() to fix this issue. Fixes: eab03c23c2a1 ("sched/eevdf: Fix vruntime adjustment on reweight") Signed-off-by: Tianchen Ding <dtcccc@linux.alibaba.com> [peterz: flip if() condition for clarity] Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Abel Wu <wuyun.abel@bytedance.com> Link: https://lkml.kernel.org/r/20240306022133.81008-3-dtcccc@linux.alibaba.com