Jan, I am running linux-next 20140429 on a mx6 board (ARM 32-bit) and after commit 5dc90cb49691755faa ("printk: enable interrupts before calling console_trylock_for_printk()") I get the following warning:
[ INFO: possible recursive locking detected ] 3.15.0-rc3-next-20140429-00001-gac246a5 #1074 Not tainted --------------------------------------------- swapper/0/0 is trying to acquire lock: (console_lock){+.+...}, at: [<808c1358>] con_init+0x14/0x29c but task is already holding lock: (console_lock){+.+...}, at: [<8006deac>] vprintk_emit+0x194/0x514 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(console_lock); lock(console_lock); *** DEADLOCK *** May be due to missing lock nesting notation 1 lock held by swapper/0/0: #0: (console_lock){+.+...}, at: [<8006deac>] vprintk_emit+0x194/0x514 stack backtrace: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.15.0-rc3-next-20140429-00001-gac2464 Backtrace: [<80011cbc>] (dump_backtrace) from [<80011e58>] (show_stack+0x18/0x1c) r6:8114b4fc r5:00000000 r4:00000000 r3:00000000 [<80011e40>] (show_stack) from [<8065e65c>] (dump_stack+0x88/0xa4) [<8065e5d4>] (dump_stack) from [<80065518>] (__lock_acquire+0x1494/0x1c10) r5:808f3f70 r4:80a7d6c0 [<80064084>] (__lock_acquire) from [<80066178>] (lock_acquire+0x68/0x7c) r10:00000000 r9:412fc09a r8:8000406a r7:00000001 r6:60000153 r5:808e8000 r4:00000000 [<80066110>] (lock_acquire) from [<8006c91c>] (console_lock+0x54/0x68) r7:befffbc0 r6:808d6db0 r5:808c1358 r4:00000001 [<8006c8c8>] (console_lock) from [<808c1358>] (con_init+0x14/0x29c) r5:808e37a4 r4:808e37a4 [<808c1344>] (con_init) from [<808c0ae4>] (console_init+0x24/0x38) r6:808d6db0 r5:808e37a4 r4:808e37a4 [<808c0ac0>] (console_init) from [<80894bb4>] (start_kernel+0x26c/0x3a4) r5:8094d5c0 r4:ffffffff [<80894948>] (start_kernel) from [<80008074>] (0x80008074) r7:808f5644 r6:808d6dac r5:808f0928 r4:10c5387d Reverting this commit causes the warning to go away. Any suggestions? Regards, Fabio Estevam -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/