kernel/linux.git/include/linux/panic.h, branch v6.19.11

taint/module: remove unnecessary taint_flag.module field

2025-11-12T18:00:15+00:00

The TAINT_RANDSTRUCT and TAINT_FWCTL flags are mistakenly set in the taint_flags table as per-module flags. While this can be trivially corrected, the issue can be avoided altogether by removing the taint_flag.module field. This is possible because, since commit 7fd8329ba502 ("taint/module: Clean up global and module taint flags handling") in 2016, the handling of module taint flags has been fully generic. Specifically, module_flags_taint() can print all flags, and the required output buffer size is properly defined in terms of TAINT_FLAGS_COUNT. The actual per-module flags are always those added to module.taints by calls to add_taint_module(). Link: https://lkml.kernel.org/r/20251022082938.26670-1-petr.pavlu@suse.com Signed-off-by: Petr Pavlu Acked-by: Petr Mladek Reviewed-by: Randy Dunlap Cc: Aaron Tomlin Cc: Luis Chamberalin Cc: Petr Pavlu Cc: Sami Tolvanen Signed-off-by: Andrew Morton

panic: introduce helper functions for panic state

2025-09-14T00:32:51+00:00

Patch series "panic: introduce panic status function family", v2. This series introduces a family of helper functions to manage panic state and updates existing code to use them. Before this series, panic state helpers were scattered and inconsistent. For example, panic_in_progress() was defined in printk/printk.c, not in panic.c or panic.h. As a result, developers had to look in unexpected places to understand or re-use panic state logic. Other checks were open- coded, duplicating logic across panic, crash, and watchdog paths. The new helpers centralize the functionality in panic.c/panic.h: - panic_try_start() - panic_reset() - panic_in_progress() - panic_on_this_cpu() - panic_on_other_cpu() Patches 1–8 add the helpers and convert panic/crash and printk/nbcon code to use them. Patch 9 fixes a bug in the watchdog subsystem by skipping checks when a panic is in progress, avoiding interference with the panic CPU. Together, this makes panic state handling simpler, more discoverable, and more robust. This patch (of 9): This patch introduces four new helper functions to abstract the management of the panic_cpu variable. These functions will be used in subsequent patches to refactor existing code. The direct use of panic_cpu can be error-prone and ambiguous, as it requires manual checks to determine which CPU is handling the panic. The new helpers clarify intent: panic_try_start(): Atomically sets the current CPU as the panicking CPU. panic_reset(): Reset panic_cpu to PANIC_CPU_INVALID. panic_in_progress(): Checks if a panic has been triggered. panic_on_this_cpu(): Returns true if the current CPU is the panic originator. panic_on_other_cpu(): Returns true if a panic is on another CPU. This change lays the groundwork for improved code readability and robustness in the panic handling subsystem. Link: https://lkml.kernel.org/r/20250825022947.1596226-1-wangjinchao600@gmail.com Link: https://lkml.kernel.org/r/20250825022947.1596226-2-wangjinchao600@gmail.com Signed-off-by: Jinchao Wang Cc: Anna Schumaker Cc: Baoquan He Cc: "Darrick J. Wong" Cc: Dave Young Cc: Doug Anderson Cc: "Guilherme G. Piccoli" Cc: Helge Deller Cc: Ingo Molnar Cc: Jason Gunthorpe Cc: Joanthan Cameron Cc: Joel Granados Cc: John Ogness Cc: Kees Cook Cc: Li Huafei Cc: "Luck, Tony" Cc: Luo Gengkun Cc: Max Kellermann Cc: Nam Cao Cc: oushixiong Cc: Petr Mladek Cc: Qianqiang Liu Cc: Sergey Senozhatsky Cc: Sohil Mehta Cc: Steven Rostedt Cc: Tejun Heo Cc: Thomas Gleinxer Cc: Thomas Zimemrmann Cc: Thorsten Blum Cc: Ville Syrjala Cc: Vivek Goyal Cc: Yicong Yang Cc: Yunhui Cui Cc: Yury Norov (NVIDIA) b Signed-off-by: Andrew Morton

Merge tag 'trace-rv-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

2025-07-30T23:23:12+00:00

Pull runtime verification updates from Steven Rostedt: - Added Linear temporal logic monitors for RT application Real-time applications may have design flaws causing them to have unexpected latency. For example, the applications may raise page faults, or may be blocked trying to take a mutex without priority inheritance. However, while attempting to implement DA monitors for these real-time rules, deterministic automaton is found to be inappropriate as the specification language. The automaton is complicated, hard to understand, and error-prone. For these cases, linear temporal logic is found to be more suitable. The LTL is more concise and intuitive. - Make printk_deferred() public The new monitors needed access to printk_deferred(). Make them visible for the entire kernel. - Add a vpanic() to allow for va_list to be passed to panic. - Add rtapp container monitor. A collection of monitors that check for common problems with real-time applications that cause unexpected latency. - Add page fault tracepoints to risc-v These tracepoints are necessary to for the RV monitor to run on risc-v. - Fix the behaviour of the rv tool with -s and idle tasks. - Allow the rv tool to gracefully terminate with SIGTERM - Adjusts dot2c not to create lines over 100 columns - Properly order nested monitors in the RV Kconfig file - Return the registration error in all DA monitor instead of 0 - Update and add new sched collection monitors Replace tss and sncid monitors with more complete sts: Not only prove that switches occur in scheduling context and scheduling needs interrupt disabled but also that each call to the scheduler disables interrupts to (optionally) switch. New monitor: nrp Preemption requires need resched which is cleared by any switch (includes a non optimal workaround for /nested/ preemptions) New monitor: sssw suspension requires setting the task to sleepable and, after the switch occurs, the task requires a wakeup to come back to runnable New monitor: opid waking and need-resched operations occur with interrupts and preemption disabled or in IRQ without explicitly disabling preemption" * tag 'trace-rv-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (48 commits) rv: Add opid per-cpu monitor rv: Add nrp and sssw per-task monitors rv: Replace tss and sncid monitors with more complete sts sched: Adapt sched tracepoints for RV task model rv: Retry when da monitor detects race conditions rv: Adjust monitor dependencies rv: Use strings in da monitors tracepoints rv: Remove trailing whitespace from tracepoint string rv: Add da_handle_start_run_event_ to per-task monitors rv: Fix wrong type cast in reactors_show() and monitor_reactor_show() rv: Fix wrong type cast in monitors_show() rv: Remove struct rv_monitor::reacting rv: Remove rv_reactor's reference counter rv: Merge struct rv_reactor_def into struct rv_reactor rv: Merge struct rv_monitor_def into struct rv_monitor rv: Remove unused field in struct rv_monitor_def rv: Return init error when registering monitors verification/rvgen: Organise Kconfig entries for nested monitors tools/dot2c: Fix generated files going over 100 column limit tools/rv: Stop gracefully also on SIGTERM ...

rcu: Move rcu_stall related sysctls into rcu/tree_stall.h

2025-07-23T09:52:47+00:00

Move sysctl_panic_on_rcu_stall and sysctl_max_rcu_stall_to_panic into the kernel/rcu subdirectory. Make these static in tree_stall.h and removed them as extern from panic.h as their scope is now confined into one file. This is part of a greater effort to move ctl tables into their respective subsystems which will reduce the merge conflicts in kernel/sysctl.c. Reviewed-by: Luis Chamberlain Reviewed-by: Joel Fernandes Reviewed-by: Kees Cook Signed-off-by: Joel Granados

panic: Add vpanic()

2025-07-09T19:27:00+00:00

vpanic() is useful for implementing runtime verification reactors. Add it. Signed-off-by: Nam Cao Reviewed-by: Petr Mladek Signed-off-by: Steven Rostedt (Google)

x86/nmi: Consolidate NMI panic variables

2025-04-01T20:25:56+00:00

Commit: c305a4e98378 ("x86: Move sysctls into arch/x86") recently moved the sysctl handling of panic_on_unrecovered_nmi and panic_on_io_nmi to x86-specific code. These variables no longer need to be declared in the generic header file. Relocate the variable definitions and declarations closer to where they are used. This makes all the NMI panic options consistent and easier to track. [ mingo: Fixed up the SHA1 of the commit reference. ] Signed-off-by: Sohil Mehta Signed-off-by: Ingo Molnar Reviewed-by: Kai Huang Acked-by: Peter Zijlstra (Intel) Reviewed-by: Nikolay Borisov Cc: Joel Granados Link: https://lore.kernel.org/r/20250327234629.3953536-3-sohil.mehta@intel.com

taint: Add TAINT_FWCTL

2025-03-06T19:13:13+00:00

Requesting a fwctl scope of access that includes mutating device debug data will cause the kernel to be tainted. Changing the device operation through things in the debug scope may cause the device to malfunction in undefined ways. This should be reflected in the TAINT flags to help any debuggers understand that something has been done. Link: https://patch.msgid.link/r/4-v5-642aa0c94070+4447f-fwctl_jgg@nvidia.com Reviewed-by: Jonathan Cameron Reviewed-by: Dave Jiang Reviewed-by: Shannon Nelson Tested-by: Dave Jiang Tested-by: Shannon Nelson Signed-off-by: Jason Gunthorpe

printk/panic: Allow cpu backtraces to be written into ringbuffer during panic

2024-08-13T12:16:22+00:00

commit 779dbc2e78d7 ("printk: Avoid non-panic CPUs writing to ringbuffer") disabled non-panic CPUs to further write messages to ringbuffer after panicked. Since the commit, non-panicked CPU's are not allowed to write to ring buffer after panicked and CPU backtrace which is triggered after panicked to sample non-panicked CPUs' backtrace no longer serves its function as it has nothing to print. Fix the issue by allowing non-panicked CPUs to write into ringbuffer while CPU backtrace is in flight. Fixes: 779dbc2e78d7 ("printk: Avoid non-panic CPUs writing to ringbuffer") Signed-off-by: Ryo Takakura Reviewed-by: Petr Mladek Link: https://lore.kernel.org/r/20240812072703.339690-1-takakura@valinux.co.jp Signed-off-by: Petr Mladek

kernel/panic: add verbose logging of kernel taints in backtraces

2024-06-25T05:25:05+00:00

With nearly 20 taint flags and respective characters, it's getting a bit difficult to remember what each taint flag character means. Add verbose logging of the set taints in the format: Tainted: [P]=PROPRIETARY_MODULE, [W]=WARN in dump_stack_print_info() when there are taints. Note that the "negative flag" G is not included. Link: https://lkml.kernel.org/r/7321e306166cb2ca2807ab8639e665baa2462e9c.1717146197.git.jani.nikula@intel.com Signed-off-by: Jani Nikula Reviewed-by: Greg Kroah-Hartman Signed-off-by: Andrew Morton

panic: make function declarations visible

2023-06-10T00:44:15+00:00

A few panic() related functions have a global definition but not declaration, which causes a warning with W=1: kernel/panic.c:710:6: error: no previous prototype for '__warn_printk' [-Werror=missing-prototypes] kernel/panic.c:756:24: error: no previous prototype for '__stack_chk_fail' [-Werror=missing-prototypes] kernel/exit.c:1917:32: error: no previous prototype for 'abort' [-Werror=missing-prototypes] __warn_printk() is called both as a global function when CONFIG_BUG is enabled, and as a local function in other configs. The other two here are called indirectly from generated or assembler code. Add prototypes for all of these. Link: https://lkml.kernel.org/r/20230517131102.934196-9-arnd@kernel.org Signed-off-by: Arnd Bergmann Cc: Boqun Feng Cc: Catalin Marinas Cc: Christoph Lameter Cc: Dennis Zhou Cc: Eric Paris Cc: Heiko Carstens Cc: Helge Deller Cc: Ingo Molnar Cc: Michael Ellerman Cc: Michal Simek Cc: Palmer Dabbelt Cc: Paul Moore Cc: Pavel Machek Cc: Peter Zijlstra Cc: Rafael J. Wysocki Cc: Russell King Cc: Tejun Heo Cc: Thomas Bogendoerfer Cc: Thomas Gleixner Cc: Waiman Long Cc: Will Deacon Signed-off-by: Andrew Morton