9eeba6138c
Impact: provide useful missing info for developers
Kernel taint can occur in several situations such as warnings,
load of prorietary or staging modules, bad page, etc...
But when such taint happens, a developer might still be working on
the kernel, expecting that lockdep is still enabled. But a taint
disables lockdep without ever warning about it.
Such a kernel behaviour doesn't really help for kernel development.
This patch adds this missing warning.
Since the taint is done most of the time after the main message that
explain the real source issue, it seems safe to warn about it inside
add_taint() so that it appears at last, without hurting the main
information.
v2: Use a generic helper to disable lockdep instead of an
open coded xchg().
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <1239412638-6739-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
47 lines
1.1 KiB
C
47 lines
1.1 KiB
C
/*
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* lib/debug_locks.c
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*
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* Generic place for common debugging facilities for various locks:
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* spinlocks, rwlocks, mutexes and rwsems.
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*
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* Started by Ingo Molnar:
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*
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* Copyright (C) 2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
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*/
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#include <linux/kernel.h>
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#include <linux/rwsem.h>
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#include <linux/mutex.h>
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#include <linux/module.h>
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#include <linux/spinlock.h>
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#include <linux/debug_locks.h>
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/*
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* We want to turn all lock-debugging facilities on/off at once,
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* via a global flag. The reason is that once a single bug has been
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* detected and reported, there might be cascade of followup bugs
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* that would just muddy the log. So we report the first one and
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* shut up after that.
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*/
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int debug_locks = 1;
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/*
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* The locking-testsuite uses <debug_locks_silent> to get a
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* 'silent failure': nothing is printed to the console when
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* a locking bug is detected.
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*/
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int debug_locks_silent;
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/*
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* Generic 'turn off all lock debugging' function:
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*/
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int debug_locks_off(void)
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{
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if (__debug_locks_off()) {
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if (!debug_locks_silent) {
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oops_in_progress = 1;
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console_verbose();
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return 1;
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}
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}
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return 0;
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}
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