From c0fe096a8aba4b00c2a928c22b7f6a3ce3e9ca97 Mon Sep 17 00:00:00 2001 From: Dmitry Safonov Date: Mon, 8 Jun 2020 21:30:26 -0700 Subject: arm64: add show_stack_loglvl() 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. Introduce show_stack_loglvl(), that eventually will substitute show_stack(). [1]: https://lore.kernel.org/lkml/20190528002412.1625-1-dima@arista.com/T/#u Signed-off-by: Dmitry Safonov Signed-off-by: Andrew Morton Cc: Catalin Marinas Cc: Russell King Cc: Will Deacon Link: http://lkml.kernel.org/r/20200418201944.482088-11-dima@arista.com Signed-off-by: Linus Torvalds --- arch/arm64/kernel/traps.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) (limited to 'arch/arm64/kernel') diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c index f602aca64baa..3621868b2fcc 100644 --- a/arch/arm64/kernel/traps.c +++ b/arch/arm64/kernel/traps.c @@ -137,12 +137,18 @@ void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk, put_task_stack(tsk); } -void show_stack(struct task_struct *tsk, unsigned long *sp) +void show_stack_loglvl(struct task_struct *tsk, unsigned long *sp, + const char *loglvl) { - dump_backtrace(NULL, tsk, KERN_DEFAULT); + dump_backtrace(NULL, tsk, loglvl); barrier(); } +void show_stack(struct task_struct *tsk, unsigned long *sp) +{ + show_stack_loglvl(tsk, sp, KERN_DEFAULT); +} + #ifdef CONFIG_PREEMPT #define S_PREEMPT " PREEMPT" #elif defined(CONFIG_PREEMPT_RT) -- cgit v1.2.3