forked from mirrors/linux
		
	 dbf520a9d7
			
		
	
	
		dbf520a9d7
		
	
	
	
	
		
			
			This reverts commit6aa9707099. Commit6aa9707099("lockdep: check that no locks held at freeze time") causes problems with NFS root filesystems. The failures were noticed on OMAP2 and 3 boards during kernel init: [ BUG: swapper/0/1 still has locks held! ] 3.9.0-rc3-00344-ga937536 #1 Not tainted ------------------------------------- 1 lock held by swapper/0/1: #0: (&type->s_umount_key#13/1){+.+.+.}, at: [<c011e84c>] sget+0x248/0x574 stack backtrace: rpc_wait_bit_killable __wait_on_bit out_of_line_wait_on_bit __rpc_execute rpc_run_task rpc_call_sync nfs_proc_get_root nfs_get_root nfs_fs_mount_common nfs_try_mount nfs_fs_mount mount_fs vfs_kern_mount do_mount sys_mount do_mount_root mount_root prepare_namespace kernel_init_freeable kernel_init Although the rootfs mounts, the system is unstable. Here's a transcript from a PM test: http://www.pwsan.com/omap/testlogs/test_v3.9-rc3/20130317194234/pm/37xxevm/37xxevm_log.txt Here's what the test log should look like: http://www.pwsan.com/omap/testlogs/test_v3.8/20130218214403/pm/37xxevm/37xxevm_log.txt Mailing list discussion is here: http://lkml.org/lkml/2013/3/4/221 Deal with this for v3.9 by reverting the problem commit, until folks can figure out the right long-term course of action. Signed-off-by: Paul Walmsley <paul@pwsan.com> Cc: Mandeep Singh Baines <msb@chromium.org> Cc: Jeff Layton <jlayton@redhat.com> Cc: Shawn Guo <shawn.guo@linaro.org> Cc: <maciej.rutecki@gmail.com> Cc: Fengguang Wu <fengguang.wu@intel.com> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Ben Chan <benchan@chromium.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Rafael J. Wysocki <rjw@sisk.pl> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
		
			
				
	
	
		
			75 lines
		
	
	
	
		
			1.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			75 lines
		
	
	
	
		
			1.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| #ifndef __LINUX_DEBUG_LOCKING_H
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| #define __LINUX_DEBUG_LOCKING_H
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| 
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| #include <linux/kernel.h>
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| #include <linux/atomic.h>
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| #include <linux/bug.h>
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| 
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| struct task_struct;
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| 
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| extern int debug_locks;
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| extern int debug_locks_silent;
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| 
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| 
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| static inline int __debug_locks_off(void)
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| {
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| 	return xchg(&debug_locks, 0);
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| }
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| 
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| /*
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|  * Generic 'turn off all lock debugging' function:
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|  */
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| extern int debug_locks_off(void);
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| 
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| #define DEBUG_LOCKS_WARN_ON(c)						\
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| ({									\
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| 	int __ret = 0;							\
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| 									\
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| 	if (!oops_in_progress && unlikely(c)) {				\
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| 		if (debug_locks_off() && !debug_locks_silent)		\
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| 			WARN_ON(1);					\
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| 		__ret = 1;						\
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| 	}								\
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| 	__ret;								\
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| })
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| 
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| #ifdef CONFIG_SMP
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| # define SMP_DEBUG_LOCKS_WARN_ON(c)			DEBUG_LOCKS_WARN_ON(c)
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| #else
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| # define SMP_DEBUG_LOCKS_WARN_ON(c)			do { } while (0)
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| #endif
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| 
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| #ifdef CONFIG_DEBUG_LOCKING_API_SELFTESTS
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|   extern void locking_selftest(void);
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| #else
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| # define locking_selftest()	do { } while (0)
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| #endif
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| 
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| struct task_struct;
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| 
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| #ifdef CONFIG_LOCKDEP
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| extern void debug_show_all_locks(void);
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| extern void debug_show_held_locks(struct task_struct *task);
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| extern void debug_check_no_locks_freed(const void *from, unsigned long len);
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| extern void debug_check_no_locks_held(struct task_struct *task);
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| #else
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| static inline void debug_show_all_locks(void)
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| {
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| }
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| 
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| static inline void debug_show_held_locks(struct task_struct *task)
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| {
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| }
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| 
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| static inline void
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| debug_check_no_locks_freed(const void *from, unsigned long len)
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| {
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| }
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| 
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| static inline void
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| debug_check_no_locks_held(struct task_struct *task)
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| {
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| }
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| #endif
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| 
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| #endif
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