user/sven/linux.git/include/linux/vt_kern.h, branch v4.10.3

tty: vgacon+sisusb, move scrolldelta to a common helper

2016-10-27T14:37:44Z

The code is mirrorred in scrolldelta implementations of both vgacon and sisusb. Let's move the code to a separate helper where we will perform a common cleanup and further changes. While we are moving the code, make it linear and save one indentation level. This is done by returning from the "!lines" then-branch immediatelly. This allows flushing the else-branch 1 level to the left, obviously. Few more new lines and comments were added too. And do not forget to export the helper function given sisusb can be built as module. Signed-off-by: Jiri Slaby Cc: Thomas Winischhofer Cc: Tomi Valkeinen Cc: Cc: Signed-off-by: Greg Kroah-Hartman

tty: vt, ignore PIO_UNIMAPCLR param

2016-06-25T16:04:48Z

We do not do hashtables for unicode fonts since 1995 (1.3.28). So it is time to remove the second parameter of con_clear_unimap and ignore the advice from userspace completely. Signed-off-by: Jiri Slaby Signed-off-by: Greg Kroah-Hartman

vt: remove lines parameter from scrollback

2016-06-25T16:04:48Z

It is always called with 0, so remove the parameter and pass the default down to scrolldelta without checking. Signed-off-by: Jiri Slaby Signed-off-by: Greg Kroah-Hartman

Merge 3.10-rc3 into tty-next

2013-05-27T01:57:53Z

We want these fixes. Signed-off-by: Greg Kroah-Hartman

vt: delete unneeded function unbind_con_driver

2013-05-20T19:27:59Z

Now there is no place use unbind_con_driver, and we can achieve unbind_con_driver's function with do_unbind_con_driver easily, so just delete it to reduce code size and duplication. Signed-off-by: Wang YanQing Signed-off-by: Greg Kroah-Hartman

tty/vt: Fix vc_deallocate() lock order

2013-05-20T19:15:59Z

Now that the tty port owns the flip buffers and i/o is allowed from the driver even when no tty is attached, the destruction of the tty port (and the flip buffers) must ensure that no outstanding work is pending. Unfortunately, this creates a lock order problem with the console_lock (see attached lockdep report [1] below). For single console deallocation, drop the console_lock prior to port destruction. When multiple console deallocation, defer port destruction until the consoles have been deallocated. tty_port_destroy() is not required if the port has not been used; remove from vc_allocate() failure path. [1] lockdep report from Dave Jones ====================================================== [ INFO: possible circular locking dependency detected ] 3.9.0+ #16 Not tainted ------------------------------------------------------- (agetty)/26163 is trying to acquire lock: blocked: ((&buf->work)){+.+...}, instance: ffff88011c8b0020, at: [] flush_work+0x5/0x2e0 but task is already holding lock: blocked: (console_lock){+.+.+.}, instance: ffffffff81c2fde0, at: [] vt_ioctl+0xb61/0x1230 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (console_lock){+.+.+.}: [] lock_acquire+0xa4/0x210 [] console_lock+0x77/0x80 [] con_flush_chars+0x2d/0x50 [] n_tty_receive_buf+0x122/0x14d0 [] flush_to_ldisc+0x119/0x170 [] process_one_work+0x211/0x700 [] worker_thread+0x11b/0x3a0 [] kthread+0xed/0x100 [] ret_from_fork+0x7c/0xb0 -> #0 ((&buf->work)){+.+...}: [] __lock_acquire+0x193a/0x1c00 [] lock_acquire+0xa4/0x210 [] flush_work+0x4e/0x2e0 [] __cancel_work_timer+0x95/0x130 [] cancel_work_sync+0x10/0x20 [] tty_port_destroy+0x12/0x20 [] vc_deallocate+0xf8/0x110 [] vt_ioctl+0xb6c/0x1230 [] tty_ioctl+0x285/0xd50 [] do_vfs_ioctl+0x305/0x530 [] sys_ioctl+0x81/0xa0 [] system_call_fastpath+0x16/0x1b other info that might help us debug this: [ 6760.076175] Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(console_lock); lock((&buf->work)); lock(console_lock); lock((&buf->work)); *** DEADLOCK *** 1 lock on stack by (agetty)/26163: #0: blocked: (console_lock){+.+.+.}, instance: ffffffff81c2fde0, at: [] vt_ioctl+0xb61/0x1230 stack backtrace: Pid: 26163, comm: (agetty) Not tainted 3.9.0+ #16 Call Trace: [] print_circular_bug+0x200/0x20e [] __lock_acquire+0x193a/0x1c00 [] ? sched_clock+0x9/0x10 [] ? sched_clock+0x9/0x10 [] ? native_sched_clock+0x20/0x80 [] lock_acquire+0xa4/0x210 [] ? flush_work+0x5/0x2e0 [] flush_work+0x4e/0x2e0 [] ? flush_work+0x5/0x2e0 [] ? mark_held_locks+0xbb/0x140 [] ? __free_pages_ok.part.57+0x93/0xc0 [] ? mark_held_locks+0xbb/0x140 [] ? __cancel_work_timer+0x82/0x130 [] __cancel_work_timer+0x95/0x130 [] cancel_work_sync+0x10/0x20 [] tty_port_destroy+0x12/0x20 [] vc_deallocate+0xf8/0x110 [] vt_ioctl+0xb6c/0x1230 [] ? lock_release_holdtime.part.30+0xa1/0x170 [] tty_ioctl+0x285/0xd50 [] ? inode_has_perm.isra.46.constprop.61+0x56/0x80 [] do_vfs_ioctl+0x305/0x530 [] ? selinux_file_ioctl+0x5b/0x110 [] sys_ioctl+0x81/0xa0 [] system_call_fastpath+0x16/0x1b Cc: Dave Jones Signed-off-by: Peter Hurley Signed-off-by: Greg Kroah-Hartman

Merge branch 'console-fixes' into drm-next

2013-02-08T02:13:43Z

(not the fbcon maintainer pull 2) fix bug in vgacon on bootup and fbcon losing fonts on startup. * console-fixes: (50 commits) fbcon: don't lose the console font across generic->chip driver switch vgacon/vt: clear buffer attributes when we load a 512 character font (v2)

fb: Yet another band-aid for fixing lockdep mess

2013-02-08T02:02:41Z

I've still got lockdep warnings even after Alan's patch, and it seems that yet more band aids are required to paper over similar paths for unbind_con_driver() and unregister_con_driver(). After this hack, lockdep warnings are finally gone. Signed-off-by: Takashi Iwai Cc: Alan Cox Cc: Florian Tobias Schandinat Cc: Jiri Kosina Cc: stable Tested-by: Sedat Dilek Signed-off-by: Andrew Morton Signed-off-by: Dave Airlie

vgacon/vt: clear buffer attributes when we load a 512 character font (v2)

2013-02-07T02:37:03Z

When we switch from 256->512 byte font rendering mode, it means the current contents of the screen is being reinterpreted. The bit that holds the high bit of the 9-bit font, may have been previously set, and thus the new font misrenders. The problem case we see is grub2 writes spaces with the bit set, so it ends up with data like 0x820, which gets reinterpreted into 0x120 char which the font translates into G with a circumflex. This flashes up on screen at boot and is quite ugly. A current side effect of this patch though is that any rendering on the screen changes color to a slightly darker color, but at least the screen no longer corrupts. v2: as suggested by hpa, always clear the attribute space, whether we are are going to or from 512 chars. Cc: stable@vger.kernel.org Signed-off-by: Dave Airlie

vt: push the tty_lock down into the map handling

2012-04-24T23:14:14Z

When we do this it becomes clear the lock we should be holding is the vc lock, and in fact many of our other helpers are properly invoked this way. We don't at this point guarantee not to race the keyboard code but the results of that appear harmless and that was true before we started as well. We now have no users of tty_lock in the console driver... Signed-off-by: Alan Cox Signed-off-by: Greg Kroah-Hartman