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ring-buffer: do not disable ring buffer on oops_in_progress
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  commit e0fdace
  Author: David Miller <davem@davemloft.net>
  Date:   Fri Aug 1 01:11:22 2008 -0700

    debug_locks: set oops_in_progress if we will log messages.

    Otherwise lock debugging messages on runqueue locks can deadlock the
    system due to the wakeups performed by printk().

    Signed-off-by: David S. Miller <davem@davemloft.net>
    Signed-off-by: Ingo Molnar <mingo@elte.hu>

Will permanently set oops_in_progress on any lockdep failure.
When this triggers it will cause any read from the ring buffer to
permanently disable the ring buffer (not to mention no locking of
printk).

This patch removes the check. It keeps the print in NMI which makes
sense. This is probably OK, since the ring buffer should not cause
something to set oops_in_progress anyway.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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Steven Rostedt authored and Steven Rostedt committed Aug 6, 2009
1 parent 0f2541d commit 464e85e
Showing 1 changed file with 1 addition and 1 deletion.
2 changes: 1 addition & 1 deletion kernel/trace/ring_buffer.c
Original file line number Diff line number Diff line change
Expand Up @@ -2486,7 +2486,7 @@ static inline int rb_ok_to_lock(void)
* buffer too. A one time deal is all you get from reading
* the ring buffer from an NMI.
*/
if (likely(!in_nmi() && !oops_in_progress))
if (likely(!in_nmi()))
return 1;

tracing_off_permanent();
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