Hi Ingo,
I built a parisc kernel with CONFIG_DEBUG_LOCKING_API_SELFTESTS enabled
recently, and got some interesting results:
double unlock: ok | ok |failed|WARNING at /home/willy/merge-2.6/kernel/mutex-debug.c:83 debug_mutex_unlock()
Backtrace:
[<0000000040144b38>] printk+0x40/0x50
[<000000004028d5f4>] init_class_Z+0xa4/0xc0
[<0000000040144b38>] printk+0x40/0x50
[<0000000040171fbc>] register_cpu_notifier+0x5c/0x78
[<0000000040340212>] lpfc_sli_issue_mbox_wait+0x138/0x1c8
[<0000000040204d01>] sg_grt_trans+0x150/0x168
[<0000000040285700>] kobject_uevent+0x8/0x20
[<0000000040304d65>] scsi_error_handler+0x9f4/0xa48
[<0000000040207450>] dump_write+0x40/0x58
[<000000004044c67c>] packet_getsockopt+0x144/0x150
[<000000004044b05c>] packet_ioctl+0x1a4/0x1b0
[<00000000404466d4>] unix_ioctl+0x154/0x168
[<000000004042d5dc>] ipv4_sysctl_forward_strategy+0x12c/0x138
[<000000004042d558>] ipv4_sysctl_forward_strategy+0xa8/0x138
[<000000004042c1d4>] ip_mc_msfget+0x16c/0x1d0
[<00000000404230a8>] ipv4_doint_and_flush_strategy+0x110/0x138
WARNING at /home/willy/merge-2.6/kernel/mutex-debug.c:86 debug_mutex_unlock()
Backtrace:
[<0000000040144b38>] printk+0x40/0x50
[<000000004028d5f4>] init_class_Z+0xa4/0xc0
[<0000000040144b38>] printk+0x40/0x50
[<0000000040171fbc>] register_cpu_notifier+0x5c/0x78
[<0000000040340212>] lpfc_sli_issue_mbox_wait+0x138/0x1c8
[<0000000040204d01>] sg_grt_trans+0x150/0x168
[<0000000040285700>] kobject_uevent+0x8/0x20
[<0000000040304d65>] scsi_error_handler+0x9f4/0xa48
[<0000000040207450>] dump_write+0x40/0x58
[<000000004044c67c>] packet_getsockopt+0x144/0x150
[<000000004044b05c>] packet_ioctl+0x1a4/0x1b0
[<00000000404466d4>] unix_ioctl+0x154/0x168
[<000000004042d5dc>] ipv4_sysctl_forward_strategy+0x12c/0x138
[<000000004042d558>] ipv4_sysctl_forward_strategy+0xa8/0x138
[<000000004042c1d4>] ip_mc_msfget+0x16c/0x1d0
[<00000000404230a8>] ipv4_doint_and_flush_strategy+0x110/0x138
failed|failed|failed|
Now, lines 83 to 86 of mutex-debug.c are:
DEBUG_LOCKS_WARN_ON(lock->owner != current_thread_info());
DEBUG_LOCKS_WARN_ON(lock->magic != lock);
DEBUG_LOCKS_WARN_ON(!lock->wait_list.prev && !lock->wait_list.next);
DEBUG_LOCKS_WARN_ON(lock->owner != current_thread_info());
Do we really need to test the same thing twice and produce the same
stack dump?
Moreover, do we want to get stack dumps while running the locking
testsuite in the first place? From various comments, it looks
like it's supposed to be turned off, but it looks like the sense of
debug_locks_silent is inverted in the definition of DEBUG_LOCKS_WARN_ON:
if (unlikely(c)) { \
if (debug_locks_silent || debug_locks_off()) \
WARN_ON(1); \
Surely that should be:
if (!debug_locks_silent && debug_locks_off())
WARN_ON(1);
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
