Re: [2.6.1-rc2-mm1][BUG] Badness in unblank_screen at drivers/char/vt.c:2793

Andrew Morton
2004-01-08T23:58:47Z

Ramon Rey Vicente <ramon.rey@augcyl.org> wrote:
>
> ...
> Jan 8 23:12:29 debian kernel: Badness in unblank_screen at drivers/char/vt.c:2793
> Jan 8 23:12:29 debian kernel: Call Trace:
> Jan 8 23:12:29 debian kernel: [unblank_screen+250/288] unblank_screen+0xfa/0x120
> Jan 8 23:12:29 debian kernel: [bust_spinlocks+37/96] bust_spinlocks+0x25/0x60
> Jan 8 23:12:29 debian kernel: [die+120/224] die+0x78/0xe0
> Jan 8 23:12:29 debian kernel: [do_invalid_op+145/160] do_invalid_op+0x91/0xa0
> Jan 8 23:12:29 debian kernel: [try_to_unmap_one+456/480] try_to_unmap_one+0x1c8/0x1e0
> Jan 8 23:12:29 debian kernel: [slab_destroy+170/256] slab_destroy+0xaa/0x100
> Jan 8 23:12:29 debian kernel: [free_pages_bulk+350/640] free_pages_bulk+0x15e/0x280
> Jan 8 23:12:29 debian kernel: [free_hot_cold_page+224/256] free_hot_cold_page+0xe0/0x100
> Jan 8 23:12:29 debian kernel: [error_code+47/64] error_code+0x2f/0x40
> Jan 8 23:12:29 debian kernel: [try_to_unmap_one+456/480] try_to_unmap_one+0x1c8/0x1e0
> Jan 8 23:12:29 debian kernel: [try_to_unmap+322/384] try_to_unmap+0x142/0x180
> Jan 8 23:12:29 debian kernel: [shrink_list+579/1408] shrink_list+0x243/0x580
> Jan 8 23:12:29 debian kernel: [do_timer+197/224] do_timer+0xc5/0xe0
> Jan 8 23:12:29 debian kernel: [do_softirq+140/160] do_softirq+0x8c/0xa0
> Jan 8 23:12:29 debian kernel: [common_interrupt+24/32] common_interrupt+0x18/0x20
> Jan 8 23:12:29 debian kernel: [__pagevec_release+24/64] __pagevec_release+0x18/0x40
> Jan 8 23:12:29 debian kernel: [shrink_cache+409/864] shrink_cache+0x199/0x360
> Jan 8 23:12:29 debian kernel: [shrink_zone+107/128] shrink_zone+0x6b/0x80
> Jan 8 23:12:29 debian kernel: [balance_pgdat+359/480] balance_pgdat+0x167/0x1e0
> Jan 8 23:12:29 debian kernel: [kswapd+254/288] kswapd+0xfe/0x120
> Jan 8 23:12:29 debian kernel: [autoremove_wake_function+0/64] autoremove_wake_function+0x0/0x40
> Jan 8 23:12:29 debian kernel: [ret_from_fork+6/32] ret_from_fork+0x6/0x20
> Jan 8 23:12:29 debian kernel: [autoremove_wake_function+0/64] autoremove_wake_function+0x0/0x40
> Jan 8 23:12:29 debian kernel: [kswapd+0/288] kswapd+0x0/0x120
> Jan 8 23:12:29 debian kernel: [kernel_thread_helper+5/36] kernel_thread_helper+0x5/0x24
> Jan 8 23:12:29 debian kernel:
> Jan 8 23:12:29 debian kernel: <6>note: kswapd0[8] exited with preempt_count 1
>

Ben, your debug stuff tripped up when we were oopsing. bust_spinlocks()
calls unblank_screen() without console_sem. I'll change it to

WARN_ON(!is_console_locked() && !oops_in_progress);

(Weren't you going to update that patch anyway?)

As for the oops itself: 2.6.1-rc2-mm1 VM is kaput, sorry. It works OK here
without the fremap changes.