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path: root/drivers/char/vt_ioctl.c
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2007-10-07VT_WAITACTIVE: Avoid returning EINTR when not necessaryLinus Torvalds
We should generally prefer to return ERESTARTNOHAND rather than EINTR, so that processes with unhandled signals that get ignored don't return EINTR. This can help with X startup issues: Fatal server error: xf86OpenConsole: VT_WAITACTIVE failed: Interrupted system call although the real fix is having the X server always retry EINTR regardless (since EINTR does happen for signals that have handlers installed). Keithp has a patch for that. Regardless, ERESTARTNOHAND is the correct thing to use. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-01VT ioctl race fixSamuel Ortiz
When calling the RELDISP VT ioctl, we are reading vt_newvt while the console workqueue could be messing with it (through change_console()). We fix this race by taking the console semaphore before reading vt_newvt. Signed-off-by: Samuel Ortiz <sameo@openedhand.com> Acked-by: Antonino Daplas <adaplas@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-09-29fix console change race exposed by CFSJan Lübbe
The new behaviour of CFS exposes a race which occurs if a switch is requested when vt_mode.mode is VT_PROCESS. The process with vc->vt_pid is signaled before vc->vt_newvt is set. This causes the switch to fail when triggered by the monitoing process because the target is still -1. [ If the signal sending fails, the subsequent "reset_vc(vc)" will then reset vt_newvt to -1, so this works for that case too. - Linus ] Signed-off-by: Jan Lübbe <jluebbe@lasnet.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08drivers/char: use __set_current_state()Milind Arun Choudhary
use __set_current_state(TASK_*) instead of current->state = TASK_*, Signed-off-by: Milind Arun Choudhary <milindchoudhary@gmail.com> Cc: Jiri Slaby <jirislaby@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-04-02[PATCH] vt: fix potential race in VT_WAITACTIVE handlerMichal Januszewski
On a multiprocessor machine the VT_WAITACTIVE ioctl call may return 0 if fg_console has already been updated in redraw_screen() but the console switch itself hasn't been completed. Fix this by checking fg_console in vt_waitactive() with the console sem held. Signed-off-by: Michal Januszewski <spock@gentoo.org> Acked-by: Antonino Daplas <adaplas@pol.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-16[PATCH] swsusp: fix suspend when console is in VT_AUTO+KD_GRAPHICS modeAndrew Johnson
When the console is in VT_AUTO+KD_GRAPHICS mode, switching to the SUSPEND_CONSOLE fails, resulting in vt_waitactive() waiting indefinitely or until the task is interrupted. This patch tests if a console switch can occur in set_console() and returns early if a console switch is not possible. [akpm@linux-foundation.org: cleanup] Signed-off-by: Andrew Johnson <ajohnson@intrinsyc.com> Acked-by: Pavel Machek <pavel@ucw.cz> Cc: "Antonino A. Daplas" <adaplas@pol.net> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11[PATCH] vt: refactor console SAK processingEric W. Biederman
This does several things. - It moves looking up of the current foreground console into process context where we can safely take the semaphore that protects this operation. - It uses the new flavor of work queue processing. - This generates a factor of do_SAK, __do_SAK that runs immediately. - This calls __do_SAK with the console semaphore held ensuring nothing else happens to the console while we process the SAK operation. - With the console SAK processing moved into process context this patch removes the xchg operations that I used to attempt to attomically update struct pid, because of the strange locking used in the SAK processing. With SAK using the normal console semaphore nothing special is needed. Cc: Oleg Nesterov <oleg@tv-sign.ru> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2006-12-13[PATCH] getting rid of all casts of k[cmz]alloc() callsRobert P. J. Day
Run this: #!/bin/sh for f in $(grep -Erl "\([^\)]*\) *k[cmz]alloc" *) ; do echo "De-casting $f..." perl -pi -e "s/ ?= ?\([^\)]*\) *(k[cmz]alloc) *\(/ = \1\(/" $f done And then go through and reinstate those cases where code is casting pointers to non-pointers. And then drop a few hunks which conflicted with outstanding work. Cc: Russell King <rmk@arm.linux.org.uk>, Ian Molton <spyro@f2s.com> Cc: Mikael Starvik <starvik@axis.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Roman Zippel <zippel@linux-m68k.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Jeff Dike <jdike@addtoit.com> Cc: Greg KH <greg@kroah.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Paul Fulghum <paulkf@microgate.com> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Karsten Keil <kkeil@suse.de> Cc: Mauro Carvalho Chehab <mchehab@infradead.org> Cc: Jeff Garzik <jeff@garzik.org> Cc: James Bottomley <James.Bottomley@steeleye.com> Cc: Ian Kent <raven@themaw.net> Cc: Steven French <sfrench@us.ibm.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Neil Brown <neilb@cse.unsw.edu.au> Cc: Jaroslav Kysela <perex@suse.cz> Cc: Takashi Iwai <tiwai@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-13[PATCH] vt: fix comments to not refer to kill_procEric W. Biederman
The code has been fixed to use kill_pid instead of kill_proc fix the comments as well. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-02[PATCH] vt: Make vt_pid a struct pid (making it pid wrap around safe).Eric W. Biederman
I took a good hard look at the locking and it appears the locking on vt_pid is the console semaphore. Every modified path is called under the console semaphore except reset_vc when it is called from fn_SAK or do_SAK both of which appear to be in interrupt context. In addition I need to be careful because in the presence of an oops the console_sem may be arbitrarily dropped. Which leads me to conclude the current locking is inadequate for my needs. Given the weird cases we could hit because of oops printing instead of introducing an extra spin lock to protect the data and keep the pid to signal and the signal to send in sync, I have opted to use xchg on just the struct pid * pointer instead. Due to console_sem we will stay in sync between vt_pid and vt_mode except for a small window during a SAK, or oops handling. SAK handling should kill any user space process that care, and oops handling we are broken anyway. Besides the worst that can happen is that I try to send the wrong signal. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Oleg Nesterov <oleg@tv-sign.ru> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-02[PATCH] vt: rework the console spawning variablesEric W. Biederman
This is such a rare path it took me a while to figure out how to test this after soring out the locking. This patch does several things. - The variables used are moved into a structure and declared in vt_kern.h - A spinlock is added so we don't have SMP races updating the values. - Instead of raw pid_t value a struct_pid is used to guard against pid wrap around issues, if the daemon to spawn a new console dies. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Oleg Nesterov <oleg@tv-sign.ru> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-29[PATCH] tty locking on resizeAlan Cox
The current kernel serializes console resizes but does not serialize the resize against the tty structure updates. This means that while two parallel resizes cannot mess up the console you can get incorrect results reported. Secondly while doing this I added vc_lock_resize() to lock and resize the console. This leaves all knowledge of the console_sem in the vt/console driver and kicks it out of the tty layer, which is good Thirdly while doing this I decided I couldn't stand "disallocate" any longer so I switched it to "deallocate". Signed-off-by: Alan Cox <alan@redhat.com> Cc: Paul Fulghum <paulkf@microgate.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-08-27[PATCH] vcsa attribute bits -> ioctl(VT_GETHIFONTMASK)Samuel Thibault
When reading /dev/vcsa while a font with more than 256 characters is loaded, one of the attribute bits records the 9th bit of the character. But depending on the console driver (vgacon or fbcon for instance), that's bit 3 or bit 0. And there is no way for userland to know that, thus no way for userland to safely grab the screen content. So here is a (tested) patch: Add a VT_GETHIFONTMASK ioctl for knowing which bit is the 9th bit for VC text (vc_hi_font_mask field of the vc_data structure). Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-30Remove obsolete #include <linux/config.h>Jörn Engel
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
2005-11-07[PATCH] Only disallow _setting_ of function key stringMarcelo Tosatti
Mikael Pettersson <mikpe@csd.uu.se> noted that the current 2.6-git (and 2.4) patch to disallow KDSKBSENT for unpriviledged users should be less restrictive allowing reading of current function key string entry, but not writing. Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30[PATCH] setkeys needs rootAndrew Morton
Because people can play games reprogramming keys and leaving traps for the next user of the console. Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-28[PATCH] Adapt drivers/char/vt_ioctl.c to non-x86Emmanuel Colbus
This code uses the x86 (non-AMD-ELAN) value of CLOCK_TICK_RATE instead of CLOCK_TICK_RATE itself, which is wrong for other archs. Signed-off-by: Emmanuel Colbus <emmanuel.colbus@ensimag.imag.fr> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-01[PATCH] convert that currently tests _NSIG directly to use valid_signal()Jesper Juhl
Convert most of the current code that uses _NSIG directly to instead use valid_signal(). This avoids gcc -W warnings and off-by-one errors. Signed-off-by: Jesper Juhl <juhl-lkml@dif.dk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-16Linux-2.6.12-rc2Linus Torvalds
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!