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| author |   Dmitry Safonov <dima@arista.com> | 2020-06-08 21:30:07 -0700 |
|---|---|---|
| committer |   Linus Torvalds <torvalds@linux-foundation.org> | 2020-06-09 09:39:10 -0700 |
| commit | 5489ab50c22771ddcad014968141b0d104d650a3 (patch) | |
| tree | da45382c2f04f70bf5f8abecb8132baf70f38874 /arch/arm/kernel/traps.c | |
| parent | arc: add show_stack_loglvl() (diff) | |
| download | linux-dev-5489ab50c22771ddcad014968141b0d104d650a3.tar.xz linux-dev-5489ab50c22771ddcad014968141b0d104d650a3.zip | |
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>
Diffstat (limited to 'arch/arm/kernel/traps.c')
| -rw-r--r-- | arch/arm/kernel/traps.c | 9 |
1 files changed, 5 insertions, 4 deletions
diff --git a/arch/arm/kernel/traps.c b/arch/arm/kernel/traps.c index 316a7687f813..7bba15fdce9f 100644 --- a/arch/arm/kernel/traps.c +++ b/arch/arm/kernel/traps.c @@ -62,7 +62,8 @@ __setup("user_debug=", user_debug_setup); static void dump_mem(const char *, const char *, unsigned long, unsigned long); -void dump_backtrace_entry(unsigned long where, unsigned long from, unsigned long frame) +void dump_backtrace_entry(unsigned long where, unsigned long from, + unsigned long frame, const char *loglvl) { unsigned long end = frame + 4 + sizeof(struct pt_regs); @@ -76,7 +77,7 @@ void dump_backtrace_entry(unsigned long where, unsigned long from, unsigned long dump_mem("", "Exception stack", frame + 4, end); } -void dump_backtrace_stm(u32 *stack, u32 instruction) +void dump_backtrace_stm(u32 *stack, u32 instruction, const char *loglvl) { char str[80], *p; unsigned int x; @@ -238,7 +239,7 @@ static void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk) pr_cont("\n"); if (ok) - c_backtrace(fp, mode); + c_backtrace(fp, mode, NULL); } #endif @@ -666,7 +667,7 @@ asmlinkage int arm_syscall(int no, struct pt_regs *regs) dump_instr("", regs); if (user_mode(regs)) { __show_regs(regs); - c_backtrace(frame_pointer(regs), processor_mode(regs)); + c_backtrace(frame_pointer(regs), processor_mode(regs), NULL); } } #endif |