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| author | Sergey Senozhatsky <sergey.senozhatsky@gmail.com> | 2017-02-06 17:42:53 +0100 |
|---|---|---|
| committer | Petr Mladek <pmladek@suse.com> | 2017-02-08 11:19:10 +0100 |
| commit | 7acac3445acde1c94054cde69ab53503d296c393 (patch) | |
| tree | 53508c90b09a00631899d2bf8aeddeee3de23bbd /kernel | |
| parent | printk: introduce per-cpu safe_print seq buffer (diff) | |
| download | linux-7acac3445acde1c94054cde69ab53503d296c393.tar.xz linux-7acac3445acde1c94054cde69ab53503d296c393.zip | |
printk: always use deferred printk when flush printk_safe lines
Always use printk_deferred() in printk_safe_flush_line().
Flushing can be done from NMI or printk_safe contexts (when
we are in panic), so we can't call console drivers, yet still
want to store the messages in the logbuf buffer. Therefore we
use a deferred printk version.
Link: http://lkml.kernel.org/r/20170206164253.GA463@tigerII.localdomain
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Tejun Heo <tj@kernel.org>
Cc: Calvin Owens <calvinowens@fb.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Suggested-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/printk/printk_safe.c | 14 |
1 files changed, 6 insertions, 8 deletions
diff --git a/kernel/printk/printk_safe.c b/kernel/printk/printk_safe.c index efc89a4e9df5..5214d326d3ba 100644 --- a/kernel/printk/printk_safe.c +++ b/kernel/printk/printk_safe.c @@ -110,17 +110,15 @@ again: return add; } -static void printk_safe_flush_line(const char *text, int len) +static inline void printk_safe_flush_line(const char *text, int len) { /* - * The buffers are flushed in NMI only on panic. The messages must - * go only into the ring buffer at this stage. Consoles will get - * explicitly called later when a crashdump is not generated. + * Avoid any console drivers calls from here, because we may be + * in NMI or printk_safe context (when in panic). The messages + * must go only into the ring buffer at this stage. Consoles will + * get explicitly called later when a crashdump is not generated. */ - if (in_nmi()) - printk_deferred("%.*s", len, text); - else - printk("%.*s", len, text); + printk_deferred("%.*s", len, text); } /* printk part of the temporary buffer line by line */ |