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path: root/drivers/tty/vt
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2015-03-26tty: Use static attribute groups for sysfs entriesTakashi Iwai
Instead of manual calls of device_create_file() and device_remove_file(), pass the static attribute groups using device_create_with_groups(). Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-07vt: use msecs_to_jiffies for time conversionNicholas Mc Guire
Converting milliseconds to jiffies by "val * HZ / 1000" is technically OK but msecs_to_jiffies(val) is the cleaner solution and handles all corner cases correctly. This is a minor API consolidation only and should make things more readable. Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org> Reviewed-by: David Herrmann <dh.herrmann@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-07tty: vt/vt: fix sparse warningLad, Prabhakar
this patch fixes following sparse warning: vt.c:1240:12: warning: symbol 'rgb_from_256' was not declared. Should it be static? Signed-off-by: Lad, Prabhakar <prabhakar.csengg@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-07vt: vt_ioctl: use msecs_to_jiffies for time conversionNicholas Mc Guire
Converting milliseconds to jiffies by "val * HZ / 1000" is technically OK but msecs_to_jiffies(val) is the cleaner solution and handles all corner cases correctly. This is a minor API consolidation only and should make things more readable. Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02vt: provide notifications on selection changesNicolas Pitre
The vcs device's poll/fasync support relies on the vt notifier to signal changes to the screen content. Notifier invocations were missing for changes that comes through the selection interface though. Fix that. Tested with BRLTTY 5.2. Signed-off-by: Nicolas Pitre <nico@linaro.org> Cc: Dave Mielke <dave@mielke.cc> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-01-09vt: fix locking around vt_bind/vt_unbindImre Deak
Currently vt_bind and vt_unbind access at least the con_driver object and registered_con_driver array without holding the console lock. Fix this by locking around the whole function in each case. Signed-off-by: Imre Deak <imre.deak@intel.com> Reviewed-by: Peter Hurley <peter@hurleysoftware.com> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-01-09vt: fix check for system/busy console drivers when unregistering themImre Deak
The default console driver (conswitchp) and busy drivers bound to a console (as reported by con_is_bound()) shouldn't be unregistered. System console drivers (without the CON_DRIVER_FLAG_MODULE flag) can be unregistered, provided they are neither default nor busy. The current code checks for the CON_DRIVER_FLAG_INIT flag but this doesn't make sense: this flag is set for a driver whenever its associated console's con_startup() function is called, which first happens when the console driver is registered (so before the console gets bound) and gets cleared when the console gets unbound. The purpose of this flag is to show if we need to call con_startup() on a console before we use it. Based on the above, do_unregister_con_driver() in its current form will allow unregistering a console driver only if it was never bound, but will refuse to unregister one that was bound and later unbound. Fix this by dropping the CON_DRIVER_FLAG_INIT check, allowing unregistering of any console driver provided that it's not the default one and it's not busy. v2: - reword the third paragraph to clarify how the fix works (Peter Hurley) v3: - unchanged v4: - Allow unregistering a system console driver too, needed by i915 to unregister vgacon. Update commit description accordingly. (Daniel) Signed-off-by: Imre Deak <imre.deak@intel.com> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-25tty: pr_warning->pr_warn and logging neateningJoe Perches
Convert the pr_warning to the more common pr_warn. Other miscellanea: o Convert unusual PR_FMT define and uses to pr_fmt o Remove unnecessary OOM message o Fix grammar in an error message o Convert a pr_warning with a KERN_ERR to pr_err Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-22vt: Fix build breakage when !CONFIG_VT_CONSOLEPeter Hurley
Commit 68952076e9226cc23ebce66d3fc2fdb8b6c04c30 ("vt: Remove vt_get_kmsg_redirect() from uapi header") fails to compile if !CONFIG_VT_CONSOLE. Move macro definition for vt_get_kmsg_redirect() up with file-scope function declarations. Reported-by: Jim Davis <jim.epost@gmail.com> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-10Merge 3.18-rc4 into tty-next.Greg Kroah-Hartman
This resolves a merge issue with drivers/tty/serial/8250/8250_mtk.c Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-05tty:vt remove obsolete struct initializerPeng Fan
This patch fixes sparse warning: "obsolete struct initializer, use C99 syntax" Signed-off-by: Peng Fan <van.freenix@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-05vt: Remove vt_get_kmsg_redirect() from uapi headerPeter Hurley
vt_get_kmsg_redirect() only has meaning to the console driver as an alias for calling vt_kmsg_redirect(). Move the macro definition to the only source file which uses it; remove from uapi/linux/vt.h Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-05tty/vt: don't set font mappings on vc not supporting thisImre Deak
We can call this function for a dummy console that doesn't support setting the font mapping, which will result in a null ptr BUG. So check for this case and return error for consoles w/o font mapping support. Reference: https://bugzilla.kernel.org/show_bug.cgi?id=59321 Signed-off-by: Imre Deak <imre.deak@intel.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-08tty/vt/keyboard: Resolve many shadow warningsMark Rustad
Many local variables were given the same name as a global. This is valid, but generates many shadow warnings in W=2 builds. Resolve them by changing the local names. Also change local variables named "up" because they shadow the semaphore "up" function. Also moved the outer declaration of the variable "a" because it is only used in one block, and that resolves all of the shadow warnings for the other declarations of "a" that have different types. Change diacr => dia, kbd => kb, rep => rpt, up => udp. Signed-off-by: Mark Rustad <mark.d.rustad@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-06-19Merge tag 'drm-intel-fixes-2014-06-17' of ↵Dave Airlie
git://anongit.freedesktop.org/drm-intel into drm-next First round of fixes for 3.16-rc, mostly cc: stable, and the vt/vgacon fixes from Daniel [1] to avoid hangs and unclaimed register errors on module load/reload. * tag 'drm-intel-fixes-2014-06-17' of git://anongit.freedesktop.org/drm-intel: drm/i915/bdw: remove erroneous chv specific workarounds from bdw code drm/i915: fix possible refcount leak when resetting forcewake drm/i915: Reorder semaphore deadlock check drm/i95: Initialize active ring->pid to -1 drm/i915: set backlight duty cycle after backlight enable for gen4 drm/i915: Avoid div-by-zero when pixel_multiplier is zero drm/i915: Disable FBC by default also on Haswell and later drm/i915: Kick out vga console drm/i915: Fixup global gtt cleanup vt: Don't ignore unbind errors in vt_unbind vt: Fix up unregistration of vt drivers vt: Fix replacement console check when unbinding
2014-06-06vt: Don't ignore unbind errors in vt_unbindDaniel Vetter
Otherwise the loop will never stop since we don't make any forward progress. Noticed while breaking this accidentally in a painful attempt to make vga_con unregistering work. With this patch we'll bail out on the first attempt, which at least leaves a useful enough system behind for debugging. Livelocks on console_lock just aren't fun. Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jslaby@suse.cz> Reviewed-by: David Herrmann <dh.herrmann@gmail.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-06-06vt: Fix up unregistration of vt driversDaniel Vetter
A bunch of issues: - We should not kick out the default console (which is tracked in conswitchp), so check for that. - Add better error codes so callers can differentiate between "something went wrong" and "your driver isn't registered already". i915 needs that so it doesn't fall over when reloading the driver and hence vga_con is already unregistered. - There's a mess with the driver flags: What we need to check for is that the driver isn't used any more, i.e. unbound completely (FLAG_INIT). And not whether it's the boot console or not (which is the only one which doesn't have FLAG_MODULE). Otherwise there's no way to kick out the boot console, which i915 wants to do to prevent havoc with vga_con interferring (which tends to hang machines). Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jslaby@suse.cz> Reviewed-by: David Herrmann <dh.herrmann@gmail.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-06-06vt: Fix replacement console check when unbindingDaniel Vetter
I don't fully understand the magic of the vt register/unregister logic, but apparently everything but the inital console (as set in the conswitchp pointer) is marked with FLAG_MODULE. Which means if something unregistered the boot vt driver (e.g. i915.ko kicking out vga_con) there's nothing left when trying to unbind e.g. fbcon through sysfs. But in most cases have the dummy console hanging around besides the boot console, so this test is fairly dubious. What we actually want is simply a different console than the one we want to unbind. v2: Correct the commit message to clarify that the dummy console isn't always around, but only in most cases (David). Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jslaby@suse.cz> Cc: David Herrmann <dh.herrmann@gmail.com> Reviewed-by: David Herrmann <dh.herrmann@gmail.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-05-28console: Remove superfluous readonly checkTakashi Iwai
uni_pagedir.readonly is never set. Let's get rid of superfluous check codes. Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-28console: Use explicit pointer type for vc_uni_pagedir* fieldsTakashi Iwai
The vc_data.vc_uni_pagedir filed is currently long int, supposedly to be served generically. This, however, leads to lots of cast to pointer, and rather it worsens the readability significantly. Actually, we have now only a single uni_pagedir map implementation, and this won't change likely. So, it'd be much more simple and error-prone to just use the exact pointer for struct uni_pagedir instead of long. Ditto for vc_uni_pagedir_loc. It's a pointer to the uni_pagedir, thus it can be changed similarly to the exact type. Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-28vt: emulate 8- and 24-bit colour codes.Adam Borowski
Most other mainstream terminals support "xterm256" colours, which means people sometimes use these blindly without checking capabilities. Because of hardware limitations of VGA consoles, colours are downgraded to 16 foregrounds and 8 backgrounds. On fbdev consoles it would be possible to support them without quality loss, but adding that would require quite a large amount of code. Signed-off-by: Adam Borowski <kilobyte@angband.pl> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-02-28vt: detect and ignore OSC codes.Adam Borowski
These can be used to send commands consisting of an arbitrary string to the terminal, most often used to set a terminal's window title or to redefine the colour palette. Our console doesn't use OSC, unlike everything else, which can lead to junk being displayed if a process sends such a code unconditionally. The rules for termination follow established practice rather than Ecma-48. Ecma-48 requires the string to use only byte values 0x08..0x0D and 0x20..0x7E, terminated with either ESC \ or 0x9C. This would disallow using 8-bit characters, which are reasonable for example in window titles. A widespread idiom is to terminate with 0x07. The behaviour for other control characters differs between terminal emulators, I followed libvte and xterm: * 0x07 and ESC anything terminate * nothing else terminates, all 8-bit values including 0x9C are considered a part of the string Signed-off-by: Adam Borowski <kilobyte@angband.pl> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-02-28vt: drop an useless enum and assignment.Adam Borowski
Signed-off-by: Adam Borowski <kilobyte@angband.pl> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-02-13vt: Fix secure clear screenPetr Písař
\E[3J console code (secure clear screen) needs to update_screen(vc) in order to write-through blanks into off-screen video memory. This has been removed accidentally in 3.6 by: commit 81732c3b2fede049a692e58a7ceabb6d18ffb18c Author: Jean-François Moine <moinejf@free.fr> Date: Thu Sep 6 19:24:13 2012 +0200 tty vt: Fix line garbage in virtual console on command line edition Signed-off-by: Petr Písař <petr.pisar@atlas.cz> Cc: stable <stable@vger.kernel.org> # 3.6 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-09-26vt: properly ignore xterm-256 colour codesAdam Borowski
This is not a bug on our side, but a misdesign in ITU T.416, yet with all popular terminals supporting these codes, people consider this to be a bug in Linux. By breaking the design principles behind SGR codes (gracefully ignoring unsupported ones should not require knowing about them), 256 colour ones tend to turn blinking on before invoking an arbitrary unrelated command. This commit doesn't add such support, merely skips such codes without ill effects. Signed-off-by: Adam Borowski <kilobyte@angband.pl> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-09-26vt: break a couple of obsolete SCOish codes.Adam Borowski
No modern terminal supports them, and SGR 38 conflicts with detecting xterm-256 colours. This also makes SGR 39 consistent with other popular terminals. Neither are used by ncurses' terminfo. Signed-off-by: Adam Borowski <kilobyte@angband.pl> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-05vt: make the default color configurableClemens Ladisch
The virtual console has (undocumented) module parameters to set the colors for italic and underlined text, but the default text color was hardcoded for some reason. This made it impossible to change the color for startup messages, or to set the default for new virtual consoles. Add a module parameter for that, and document the entire bunch. Any hacker who thinks that a command prompt on a "black screen with white font" is not supicious enough can now use the kernel parameter vt.color=10 to get a nice, evil green. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-26tty: Remove dead codeAndreas Platschek
-> The ledptrs[] array is never initialized. -> There is no place where kbd->ledmode is set to LED_SHOW_MEM therefore the if statement does not make much sense. -> Since LED_SHOW_MEM is not used, it can be removed from the header file as well. Signed-off-by: Andreas Platschek <andi.platschek@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-23tty: Fix unsafe vt paste_selection()Peter Hurley
Convert the tty_buffer_flush() exclusion mechanism to a public interface - tty_buffer_lock/unlock_exclusive() - and use the interface to safely write the paste selection to the line discipline. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-23tty: Convert termios_mutex to termios_rwsemPeter Hurley
termios is commonly accessed unsafely (especially by N_TTY) because the existing mutex forces exclusive access. Convert existing usage. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-23tty: Make ldisc input flow control concurrency-friendlyPeter Hurley
Although line discipline receiving is single-producer/single-consumer, using tty->receive_room to manage flow control creates unnecessary critical regions requiring additional lock use. Instead, introduce the optional .receive_buf2() ldisc method which returns the # of bytes actually received. Serialization is guaranteed by the caller. In turn, the line discipline should schedule the buffer work item whenever space becomes available; ie., when there is room to receive data and receive_room() previously returned 0 (the buffer work item stops processing if receive_buf2() returns 0). Note the 'no room' state need not be atomic despite concurrent use by two threads because only the buffer work thread can set the state and only the read() thread can clear the state. Add n_tty_receive_buf2() as the receive_buf2() method for N_TTY. Provide a public helper function, tty_ldisc_receive_buf(), to use when directly accessing the receive_buf() methods. Line disciplines not using input flow control can continue to set tty->receive_room to a fixed value and only provide the receive_buf() method. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-03Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull second set of VFS changes from Al Viro: "Assorted f_pos race fixes, making do_splice_direct() safe to call with i_mutex on parent, O_TMPFILE support, Jeff's locks.c series, ->d_hash/->d_compare calling conventions changes from Linus, misc stuff all over the place." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits) Document ->tmpfile() ext4: ->tmpfile() support vfs: export lseek_execute() to modules lseek_execute() doesn't need an inode passed to it block_dev: switch to fixed_size_llseek() cpqphp_sysfs: switch to fixed_size_llseek() tile-srom: switch to fixed_size_llseek() proc_powerpc: switch to fixed_size_llseek() ubi/cdev: switch to fixed_size_llseek() pci/proc: switch to fixed_size_llseek() isapnp: switch to fixed_size_llseek() lpfc: switch to fixed_size_llseek() locks: give the blocked_hash its own spinlock locks: add a new "lm_owner_key" lock operation locks: turn the blocked_list into a hashtable locks: convert fl_link to a hlist_node locks: avoid taking global lock if possible when waking up blocked waiters locks: protect most of the file_lock handling with i_lock locks: encapsulate the fl_link list handling locks: make "added" in __posix_lock_file a bool ...
2013-06-29vc: switch to fixed_size_llseek()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-06-24Merge 3.10-rc7 into tty-nextGreg Kroah-Hartman
We want the tty fixes in this branch as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-17tty/vt: Return EBUSY if deallocating VT1 and it is busyRoss Lagerwall
Commit 421b40a6286e ("tty/vt: Fix vc_deallocate() lock order") changed the behavior when deallocating VT 1. Previously if trying to deallocate VT1 and it is busy, we would return EBUSY. The commit changed this to return 0 (success). This commit restores the old behavior. Signed-off-by: Ross Lagerwall <rosslagerwall@gmail.com> Tested-by: Mikael Pettersson <mikpe@it.uu.se> Acked-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-27Merge 3.10-rc3 into tty-nextGreg Kroah-Hartman
We want these fixes. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-20TTY:vt: convert remain take_over_console's users to do_take_over_consoleWang YanQing
Impact: 1:convert all remain take_over_console to do_take_over_console 2:update take_over_console to do_take_over_console in comment Commit dc9641895abb ("vt: delete unneeded functions register_con_driver|take_over_console") delete take_over_console, but forget to convert remain take_over_console's users to new API do_take_over_console, this patch fix it. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Wang YanQing <udknight@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-20vt: delete unneeded function unregister_con_driverWang YanQing
Now there is no place use unregister_con_driver, and we can achieve unregister_con_driver's function with unregister_con_driver easily, so just delete it to reduce code size and duplication. Signed-off-by: Wang YanQing <udknight@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-20fbcon: convert last two unregister_con_driver call to do_unregister_con_driverWang YanQing
There are only two place use unregister_con_driver now, this patch convert them to do_unregister_con_driver too, then we can delete unregister_con_driver whos function can be achieved with do_unregister_con_driver easily to reduce code size and duplication. Signed-off-by: Wang YanQing <udknight@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-20vt: delete unneeded function bind_con_driverWang YanQing
Now there is no place use bind_con_driver, and do_bind_con_driver can achieve bind_con_driver's function easily, so just delete it to reduce code size and duplication. Signed-off-by: Wang YanQing <udknight@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-20vt: convert last bind_con_driver call to do_bind_con_driverWang YanQing
There is only one place use bind_con_driver now, this patch convert it to do_bind_con_driver too, then we can delete bind_con_driver whos function can be replaced by do_bind_con_driver easily to reduce code size and duplication. Signed-off-by: Wang YanQing <udknight@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-20vt: delete unneeded function unbind_con_driverWang YanQing
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 <udknight@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-20vt: convert last unbind_con_driver call to do_unbind_con_driverWang YanQing
There is only one place use unbind_con_driver, this patch convert it to do_unbind_con_driver too, then we can delete unbind_con_driver to reduce code size and duplication. Signed-off-by: Wang YanQing <udknight@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-20vt: delete unneeded functions register_con_driver|take_over_consoleWang YanQing
Now there is no place use register_con_driver|take_over_console, and we can achieve their function with do_register_con_driver| do_take_over_console easily, so just delete them to reduce code duplication. Signed-off-by: Wang YanQing <udknight@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-20tty/vt: Fix vc_deallocate() lock orderPeter Hurley
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 <davej@redhat.com> ====================================================== [ 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: [<ffffffff81062065>] flush_work+0x5/0x2e0 but task is already holding lock: blocked: (console_lock){+.+.+.}, instance: ffffffff81c2fde0, at: [<ffffffff813bc201>] vt_ioctl+0xb61/0x1230 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (console_lock){+.+.+.}: [<ffffffff810b3f74>] lock_acquire+0xa4/0x210 [<ffffffff810416c7>] console_lock+0x77/0x80 [<ffffffff813c3dcd>] con_flush_chars+0x2d/0x50 [<ffffffff813b32b2>] n_tty_receive_buf+0x122/0x14d0 [<ffffffff813b7709>] flush_to_ldisc+0x119/0x170 [<ffffffff81064381>] process_one_work+0x211/0x700 [<ffffffff8106498b>] worker_thread+0x11b/0x3a0 [<ffffffff8106ce5d>] kthread+0xed/0x100 [<ffffffff81601cac>] ret_from_fork+0x7c/0xb0 -> #0 ((&buf->work)){+.+...}: [<ffffffff810b349a>] __lock_acquire+0x193a/0x1c00 [<ffffffff810b3f74>] lock_acquire+0xa4/0x210 [<ffffffff810620ae>] flush_work+0x4e/0x2e0 [<ffffffff81065305>] __cancel_work_timer+0x95/0x130 [<ffffffff810653b0>] cancel_work_sync+0x10/0x20 [<ffffffff813b8212>] tty_port_destroy+0x12/0x20 [<ffffffff813c65e8>] vc_deallocate+0xf8/0x110 [<ffffffff813bc20c>] vt_ioctl+0xb6c/0x1230 [<ffffffff813b01a5>] tty_ioctl+0x285/0xd50 [<ffffffff811ba825>] do_vfs_ioctl+0x305/0x530 [<ffffffff811baad1>] sys_ioctl+0x81/0xa0 [<ffffffff81601d59>] 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: [<ffffffff813bc201>] vt_ioctl+0xb61/0x1230 stack backtrace: Pid: 26163, comm: (agetty) Not tainted 3.9.0+ #16 Call Trace: [<ffffffff815edb14>] print_circular_bug+0x200/0x20e [<ffffffff810b349a>] __lock_acquire+0x193a/0x1c00 [<ffffffff8100a269>] ? sched_clock+0x9/0x10 [<ffffffff8100a269>] ? sched_clock+0x9/0x10 [<ffffffff8100a200>] ? native_sched_clock+0x20/0x80 [<ffffffff810b3f74>] lock_acquire+0xa4/0x210 [<ffffffff81062065>] ? flush_work+0x5/0x2e0 [<ffffffff810620ae>] flush_work+0x4e/0x2e0 [<ffffffff81062065>] ? flush_work+0x5/0x2e0 [<ffffffff810b15db>] ? mark_held_locks+0xbb/0x140 [<ffffffff8113c8a3>] ? __free_pages_ok.part.57+0x93/0xc0 [<ffffffff810b15db>] ? mark_held_locks+0xbb/0x140 [<ffffffff810652f2>] ? __cancel_work_timer+0x82/0x130 [<ffffffff81065305>] __cancel_work_timer+0x95/0x130 [<ffffffff810653b0>] cancel_work_sync+0x10/0x20 [<ffffffff813b8212>] tty_port_destroy+0x12/0x20 [<ffffffff813c65e8>] vc_deallocate+0xf8/0x110 [<ffffffff813bc20c>] vt_ioctl+0xb6c/0x1230 [<ffffffff810aec41>] ? lock_release_holdtime.part.30+0xa1/0x170 [<ffffffff813b01a5>] tty_ioctl+0x285/0xd50 [<ffffffff812b00f6>] ? inode_has_perm.isra.46.constprop.61+0x56/0x80 [<ffffffff811ba825>] do_vfs_ioctl+0x305/0x530 [<ffffffff812b04db>] ? selinux_file_ioctl+0x5b/0x110 [<ffffffff811baad1>] sys_ioctl+0x81/0xa0 [<ffffffff81601d59>] system_call_fastpath+0x16/0x1b Cc: Dave Jones <davej@redhat.com> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-01Merge 3.9-rc5 into tty-nextGreg Kroah-Hartman
We need the fixes here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-26vt: synchronize_rcu() under spinlock is not nice...Al Viro
vcs_poll_data_free() calls unregister_vt_notifier(), which calls atomic_notifier_chain_unregister(), which calls synchronize_rcu(). Do it *after* we'd dropped ->f_lock. Cc: stable@vger.kernel.org (all kernels since 2.6.37) Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-03-18driver: tty: vt: remove cast for kmalloc return valueZhang Yanfei
remove cast for kmalloc return value. Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-02-26Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs pile (part one) from Al Viro: "Assorted stuff - cleaning namei.c up a bit, fixing ->d_name/->d_parent locking violations, etc. The most visible changes here are death of FS_REVAL_DOT (replaced with "has ->d_weak_revalidate()") and a new helper getting from struct file to inode. Some bits of preparation to xattr method interface changes. Misc patches by various people sent this cycle *and* ocfs2 fixes from several cycles ago that should've been upstream right then. PS: the next vfs pile will be xattr stuff." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (46 commits) saner proc_get_inode() calling conventions proc: avoid extra pde_put() in proc_fill_super() fs: change return values from -EACCES to -EPERM fs/exec.c: make bprm_mm_init() static ocfs2/dlm: use GFP_ATOMIC inside a spin_lock ocfs2: fix possible use-after-free with AIO ocfs2: Fix oops in ocfs2_fast_symlink_readpage() code path get_empty_filp()/alloc_file() leave both ->f_pos and ->f_version zero target: writev() on single-element vector is pointless export kernel_write(), convert open-coded instances fs: encode_fh: return FILEID_INVALID if invalid fid_type kill f_vfsmnt vfs: kill FS_REVAL_DOT by adding a d_weak_revalidate dentry op nfsd: handle vfs_getattr errors in acl protocol switch vfs_getattr() to struct path default SET_PERSONALITY() in linux/elf.h ceph: prepopulate inodes only when request is aborted d_hash_and_lookup(): export, switch open-coded instances 9p: switch v9fs_set_create_acl() to inode+fid, do it before d_instantiate() 9p: split dropping the acls from v9fs_set_create_acl() ...
2013-02-25Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linuxLinus Torvalds
Pull drm merge from Dave Airlie: "Highlights: - TI LCD controller KMS driver - TI OMAP KMS driver merged from staging - drop gma500 stub driver - the fbcon locking fixes - the vgacon dirty like zebra fix. - open firmware videomode and hdmi common code helpers - major locking rework for kms object handling - pageflip/cursor won't block on polling anymore! - fbcon helper and prime helper cleanups - i915: all over the map, haswell power well enhancements, valleyview macro horrors cleaned up, killing lots of legacy GTT code, - radeon: CS ioctl unification, deprecated UMS support, gpu reset rework, VM fixes - nouveau: reworked thermal code, external dp/tmds encoder support (anx9805), fences sleep instead of polling, - exynos: all over the driver fixes." Lovely conflict in radeon/evergreen_cs.c between commit de0babd60d8d ("drm/radeon: enforce use of radeon_get_ib_value when reading user cmd") and the new changes that modified that evergreen_dma_cs_parse() function. * 'drm-next' of git://people.freedesktop.org/~airlied/linux: (508 commits) drm/tilcdc: only build on arm drm/i915: Revert hdmi HDP pin checks drm/tegra: Add list of framebuffers to debugfs drm/tegra: Fix color expansion drm/tegra: Split DC_CMD_STATE_CONTROL register write drm/tegra: Implement page-flipping support drm/tegra: Implement VBLANK support drm/tegra: Implement .mode_set_base() drm/tegra: Add plane support drm/tegra: Remove bogus tegra_framebuffer structure drm: Add consistency check for page-flipping drm/radeon: Use generic HDMI infoframe helpers drm/tegra: Use generic HDMI infoframe helpers drm: Add EDID helper documentation drm: Add HDMI infoframe helpers video: Add generic HDMI infoframe helpers drm: Add some missing forward declarations drm: Move mode tables to drm_edid.c drm: Remove duplicate drm_mode_cea_vic() gma500: Fix n, m1 and m2 clock limits for sdvo and lvds ...