Dmitry Safonov 5489ab50c2 arm/asm: add loglvl to c_backtrace()
Currently, the log-level of show_stack() depends on a platform
realization.  It creates situations where the headers are printed with
lower log level or higher than the stacktrace (depending on a platform or
user).

Furthermore, it forces the logic decision from user to an architecture
side.  In result, some users as sysrq/kdb/etc are doing tricks with
temporary rising console_loglevel while printing their messages.  And in
result it not only may print unwanted messages from other CPUs, but also
omit printing at all in the unlucky case where the printk() was deferred.

Introducing log-level parameter and KERN_UNSUPPRESSED [1] seems an easier
approach than introducing more printk buffers.  Also, it will consolidate
printings with headers.

Add log level argument to c_backtrace() as a preparation for introducing
show_stack_loglvl().

[1]: https://lore.kernel.org/lkml/20190528002412.1625-1-dima@arista.com/T/#u

Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Will Deacon <will@kernel.org>
Link: http://lkml.kernel.org/r/20200418201944.482088-5-dima@arista.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:10 -07:00

39 lines
911 B
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASMARM_TRAP_H
#define _ASMARM_TRAP_H
#include <linux/list.h>
struct pt_regs;
struct task_struct;
struct undef_hook {
struct list_head node;
u32 instr_mask;
u32 instr_val;
u32 cpsr_mask;
u32 cpsr_val;
int (*fn)(struct pt_regs *regs, unsigned int instr);
};
void register_undef_hook(struct undef_hook *hook);
void unregister_undef_hook(struct undef_hook *hook);
static inline int __in_irqentry_text(unsigned long ptr)
{
extern char __irqentry_text_start[];
extern char __irqentry_text_end[];
return ptr >= (unsigned long)&__irqentry_text_start &&
ptr < (unsigned long)&__irqentry_text_end;
}
extern void __init early_trap_init(void *);
extern void dump_backtrace_entry(unsigned long where, unsigned long from,
unsigned long frame, const char *loglvl);
extern void ptrace_break(struct pt_regs *regs);
extern void *vectors_page;
#endif