mirror of
https://github.com/raspberrypi/linux.git
synced 2025-12-06 10:00:17 +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 <wangjinchao600@gmail.com> Cc: Anna Schumaker <anna.schumaker@oracle.com> Cc: Baoquan He <bhe@redhat.com> Cc: "Darrick J. Wong" <djwong@kernel.org> Cc: Dave Young <dyoung@redhat.com> Cc: Doug Anderson <dianders@chromium.org> Cc: "Guilherme G. Piccoli" <gpiccoli@igalia.com> Cc: Helge Deller <deller@gmx.de> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Joanthan Cameron <Jonathan.Cameron@huawei.com> Cc: Joel Granados <joel.granados@kernel.org> Cc: John Ogness <john.ogness@linutronix.de> Cc: Kees Cook <kees@kernel.org> Cc: Li Huafei <lihuafei1@huawei.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Luo Gengkun <luogengkun@huaweicloud.com> Cc: Max Kellermann <max.kellermann@ionos.com> Cc: Nam Cao <namcao@linutronix.de> Cc: oushixiong <oushixiong@kylinos.cn> Cc: Petr Mladek <pmladek@suse.com> Cc: Qianqiang Liu <qianqiang.liu@163.com> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Sohil Mehta <sohil.mehta@intel.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tejun Heo <tj@kernel.org> Cc: Thomas Gleinxer <tglx@linutronix.de> Cc: Thomas Zimemrmann <tzimmermann@suse.de> Cc: Thorsten Blum <thorsten.blum@linux.dev> Cc: Ville Syrjala <ville.syrjala@linux.intel.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Yicong Yang <yangyicong@hisilicon.com> Cc: Yunhui Cui <cuiyunhui@bytedance.com> Cc: Yury Norov (NVIDIA) <yury.norov@gmail.com>b Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
107 lines
3.0 KiB
C
107 lines
3.0 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
#ifndef _LINUX_PANIC_H
|
|
#define _LINUX_PANIC_H
|
|
|
|
#include <linux/compiler_attributes.h>
|
|
#include <linux/stdarg.h>
|
|
#include <linux/types.h>
|
|
|
|
struct pt_regs;
|
|
|
|
extern long (*panic_blink)(int state);
|
|
__printf(1, 2)
|
|
void panic(const char *fmt, ...) __noreturn __cold;
|
|
__printf(1, 0)
|
|
void vpanic(const char *fmt, va_list args) __noreturn __cold;
|
|
void nmi_panic(struct pt_regs *regs, const char *msg);
|
|
void check_panic_on_warn(const char *origin);
|
|
extern void oops_enter(void);
|
|
extern void oops_exit(void);
|
|
extern bool oops_may_print(void);
|
|
|
|
extern bool panic_triggering_all_cpu_backtrace;
|
|
extern int panic_timeout;
|
|
extern unsigned long panic_print;
|
|
extern int panic_on_oops;
|
|
extern int panic_on_warn;
|
|
|
|
extern unsigned long panic_on_taint;
|
|
extern bool panic_on_taint_nousertaint;
|
|
|
|
extern int sysctl_panic_on_stackoverflow;
|
|
|
|
extern bool crash_kexec_post_notifiers;
|
|
|
|
extern void __stack_chk_fail(void);
|
|
void abort(void);
|
|
|
|
/*
|
|
* panic_cpu is used for synchronizing panic() and crash_kexec() execution. It
|
|
* holds a CPU number which is executing panic() currently. A value of
|
|
* PANIC_CPU_INVALID means no CPU has entered panic() or crash_kexec().
|
|
*/
|
|
extern atomic_t panic_cpu;
|
|
#define PANIC_CPU_INVALID -1
|
|
|
|
bool panic_try_start(void);
|
|
void panic_reset(void);
|
|
bool panic_in_progress(void);
|
|
bool panic_on_this_cpu(void);
|
|
bool panic_on_other_cpu(void);
|
|
|
|
/*
|
|
* Only to be used by arch init code. If the user over-wrote the default
|
|
* CONFIG_PANIC_TIMEOUT, honor it.
|
|
*/
|
|
static inline void set_arch_panic_timeout(int timeout, int arch_default_timeout)
|
|
{
|
|
if (panic_timeout == arch_default_timeout)
|
|
panic_timeout = timeout;
|
|
}
|
|
|
|
/* This cannot be an enum because some may be used in assembly source. */
|
|
#define TAINT_PROPRIETARY_MODULE 0
|
|
#define TAINT_FORCED_MODULE 1
|
|
#define TAINT_CPU_OUT_OF_SPEC 2
|
|
#define TAINT_FORCED_RMMOD 3
|
|
#define TAINT_MACHINE_CHECK 4
|
|
#define TAINT_BAD_PAGE 5
|
|
#define TAINT_USER 6
|
|
#define TAINT_DIE 7
|
|
#define TAINT_OVERRIDDEN_ACPI_TABLE 8
|
|
#define TAINT_WARN 9
|
|
#define TAINT_CRAP 10
|
|
#define TAINT_FIRMWARE_WORKAROUND 11
|
|
#define TAINT_OOT_MODULE 12
|
|
#define TAINT_UNSIGNED_MODULE 13
|
|
#define TAINT_SOFTLOCKUP 14
|
|
#define TAINT_LIVEPATCH 15
|
|
#define TAINT_AUX 16
|
|
#define TAINT_RANDSTRUCT 17
|
|
#define TAINT_TEST 18
|
|
#define TAINT_FWCTL 19
|
|
#define TAINT_FLAGS_COUNT 20
|
|
#define TAINT_FLAGS_MAX ((1UL << TAINT_FLAGS_COUNT) - 1)
|
|
|
|
struct taint_flag {
|
|
char c_true; /* character printed when tainted */
|
|
char c_false; /* character printed when not tainted */
|
|
bool module; /* also show as a per-module taint flag */
|
|
const char *desc; /* verbose description of the set taint flag */
|
|
};
|
|
|
|
extern const struct taint_flag taint_flags[TAINT_FLAGS_COUNT];
|
|
|
|
enum lockdep_ok {
|
|
LOCKDEP_STILL_OK,
|
|
LOCKDEP_NOW_UNRELIABLE,
|
|
};
|
|
|
|
extern const char *print_tainted(void);
|
|
extern const char *print_tainted_verbose(void);
|
|
extern void add_taint(unsigned flag, enum lockdep_ok);
|
|
extern int test_taint(unsigned flag);
|
|
extern unsigned long get_taint(void);
|
|
|
|
#endif /* _LINUX_PANIC_H */
|