mirrors/linux-stable
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git synced 2024-10-02 23:27:06 +00:00
Code Issues Releases Wiki Activity

arm: wire up dump_backtrace_{entry,stm}

Browse source 
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.

Now that c_backtrace() always emits correct loglvl, use it for printing.

[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/20200418201944.482088-8-dima@arista.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Dmitry Safonov 2020-06-08 21:30:16 -07:00 committed by Linus Torvalds
parent ee65ca01c6
commit 34135eacae
1 changed files with 7 additions and 5 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

12
arch/arm/kernel/traps.c
View file

@ -68,13 +68,15 @@ void dump_backtrace_entry(unsigned long where, unsigned long from,
unsigned long end = frame + 4 + sizeof(struct pt_regs);
#ifdef CONFIG_KALLSYMS
printk("[<%08lx>] (%ps) from [<%08lx>] (%pS)\n", where, (void *)where, from, (void *)from);
printk("%s[<%08lx>] (%ps) from [<%08lx>] (%pS)\n",
loglvl, where, (void *)where, from, (void *)from);
#else
printk("Function entered at [<%08lx>] from [<%08lx>]\n", where, from);
printk("%sFunction entered at [<%08lx>] from [<%08lx>]\n",
loglvl, where, from);
#endif
if (in_entry_text(from) && end <= ALIGN(frame, THREAD_SIZE))
dump_mem("", "Exception stack", frame + 4, end);
dump_mem(loglvl, "Exception stack", frame + 4, end);
}
void dump_backtrace_stm(u32 *stack, u32 instruction, const char *loglvl)
@ -89,12 +91,12 @@ void dump_backtrace_stm(u32 *stack, u32 instruction, const char *loglvl)
if (++x == 6) {
x = 0;
p = str;
printk("%s\n", str);
printk("%s%s\n", loglvl, str);
}
}
}
if (p != str)
printk("%s\n", str);
printk("%s%s\n", loglvl, str);
}
#ifndef CONFIG_ARM_UNWIND