linux/drivers/char
Neil Horman d6580a9f15 kexec: sysrq: simplify sysrq-c handler
Currently the sysrq-c handler is bit over-engineered.  Its behavior is
dependent on a few compile time and run time factors that alter its
behavior which is really unnecessecary.

If CONFIG_KEXEC is not configured, sysrq-c, crashes the system with a NULL
pointer dereference.  If CONFIG_KEXEC is configured, it calls crash_kexec
directly, which implies that the kexec kernel will either be booted (if
its been previously loaded), or it will simply do nothing (the no kexec
kernel has been loaded).

It would be much easier to just simplify the whole thing to dereference a
NULL pointer all the time regardless of configuration.  That way, it will
always try to crash the system, and if a kexec kernel has been loaded into
reserved space, it will still boot from the page fault trap handler
(assuming panic_on_oops is set appropriately).

[akpm@linux-foundation.org: build fix]
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Cc: Brayan Arraes <brayan@yack.com.br>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-18 13:03:59 -07:00
..
agp [IA64] Convert ia64 to use int-ll64.h 2009-06-17 09:33:49 -07:00
hw_random MIPS: hwrng: Add TX4939 RNG driver 2009-06-17 11:06:27 +01:00
ip2 tty: rewrite the ldisc locking 2009-06-11 08:51:01 -07:00
ipmi ipmi: remove driver_data direct access of struct device 2009-06-15 21:30:27 -07:00
mwave mwave: struct device - replace bus_id with dev_name(), dev_set_name() 2009-01-06 10:44:38 -08:00
pcmcia tty: Add carrier processing on close to the tty_port core 2009-06-11 08:50:56 -07:00
rio rio: addition has higher precedence than ?: 2009-04-06 14:36:43 -07:00
tpm TPM: get_event_name stack corruption 2009-05-20 08:30:05 +10:00
xilinx_hwicap xilinx_hwicap: remove improper wording in license statement 2008-12-17 11:23:07 -08:00
.gitignore
amiserial.c trivial: typo (en|dis|avail|remove)bale -> (en|dis|avail|remove)able 2009-06-12 18:01:45 +02:00
apm-emulation.c APM emulation: Notify about all suspend events, not just APM invoked ones (v2) 2008-07-16 23:27:02 +02:00
applicom.c applicom: Auto-load applicom module when device opened. 2009-04-06 14:36:30 -07:00
applicom.h
bfin_jtag_comm.c tty: bfin_jtag_comm: emulate a TTY over the Blackfin EMUDAT/JTAG interface 2009-06-11 08:51:06 -07:00
bfin-otp.c Blackfin char driver for Blackfin on-chip OTP memory (v3) 2008-04-25 08:04:56 +08:00
briq_panel.c briq_panel: BKL pushdown 2008-06-20 14:05:55 -06:00
bsr.c trivial: drivers/char/bsr.c: Storage class should be before const qualifier 2009-03-30 15:22:02 +02:00
cd1865.h
ChangeLog
consolemap.c consolemap: indentation & braces disagree - reindent 2009-01-06 15:59:30 -08:00
cp437.uni unicode table for cp437 2008-12-13 11:25:49 -08:00
cs5535_gpio.c Add a bunch of cycle_kernel_lock() calls 2008-06-20 14:05:53 -06:00
cyclades.c tty: rewrite the ldisc locking 2009-06-11 08:51:01 -07:00
defkeymap.c_shipped Fix default compose table initialization 2008-03-03 14:53:16 -08:00
defkeymap.map
digi1.h
digiFep1.h
digiPCI.h
ds1302.c rtc: use bcd2bin/bin2bcd 2008-10-20 08:52:41 -07:00
ds1620.c [ARM] netwinder: clean up GPIO naming 2008-12-13 09:12:07 +00:00
dsp56k.c device create: char: convert device_create_drvdata to device_create 2008-10-16 09:24:42 -07:00
dtlk.c Add a bunch of cycle_kernel_lock() calls 2008-06-20 14:05:53 -06:00
efirtc.c drivers/char/efirtc.c: removed duplicated #include 2008-08-04 16:59:56 -07:00
epca.c tty: rewrite the ldisc locking 2009-06-11 08:51:01 -07:00
epca.h epca: use tty_port 2008-07-20 17:12:36 -07:00
epcaconfig.h
esp.c esp: fix section mismatch warning 2009-04-07 08:31:03 -07:00
generic_nvram.c driver/char/generic_nvram: fix banner 2008-06-12 18:05:41 -07:00
generic_serial.c tty: Remove some pointless casts 2009-01-02 10:19:40 -08:00
genrtc.c genrtc: BKL pushdown 2008-06-20 14:05:57 -06:00
hangcheck-timer.c drivers/char/: Spelling fixes 2008-02-03 17:11:42 +02:00
hpet.c irq: change ACPI GSI APIs to also take a device argument 2009-04-28 12:21:17 +02:00
hvc_beat.c powerpc/cell: Use correct types in beat files 2009-01-08 16:25:16 +11:00
hvc_console.c hvc_console: Remove tty->low_latency 2009-01-16 16:15:16 +11:00
hvc_console.h powerpc: Make open count variables signed in hvcs/hvsi/hvc_console 2008-12-03 21:04:13 +11:00
hvc_irq.c hvc_console: Call free_irq() only if request_irq() was successful 2009-01-13 14:48:01 +11:00
hvc_iseries.c drivers/hvc: Add missing of_node_put 2008-12-03 21:04:09 +11:00
hvc_iucv.c [S390] pm: hvc_iucv power management callbacks 2009-06-16 10:31:19 +02:00
hvc_rtas.c [POWERPC] hvc_rtas_init() must be __init 2008-02-14 22:11:02 +11:00
hvc_udbg.c powerpc: udbg-based backend for hvc_console 2008-11-19 16:04:25 +11:00
hvc_vio.c drivers/hvc: Add missing of_node_put 2008-12-03 21:04:09 +11:00
hvc_xen.c hvc_console: Add a hangup notifier for backends 2008-10-22 10:59:54 +11:00
hvcs.c hvcs: remove driver_data direct access of struct device 2009-06-15 21:30:27 -07:00
hvsi.c hvc_console: Remove tty->low_latency on pseries backends 2009-03-11 10:44:26 +11:00
i8k.c i8k: Add Dell Vostro systems 2009-01-02 10:28:32 -08:00
isicom.c Char: isicom: fix build warning 2009-06-18 13:03:54 -07:00
istallion.c tty: Add carrier processing on close to the tty_port core 2009-06-11 08:50:56 -07:00
Kconfig drivers/char/rtc: disable legacy RTC driver on Blackfin systems 2009-06-18 13:03:43 -07:00
keyboard.c Input: keyboard - fix potential out of bound access to key_map 2008-10-08 23:45:36 -04:00
lp.c device create: char: convert device_create_drvdata to device_create 2008-10-16 09:24:42 -07:00
Makefile tty: bfin_jtag_comm: emulate a TTY over the Blackfin EMUDAT/JTAG interface 2009-06-11 08:51:06 -07:00
mbcs.c mbcs: cdev lock_kernel() pushdown 2008-06-20 14:05:48 -06:00
mbcs.h MBCS: convert dmareadlock to mutex 2008-02-07 08:42:25 -08:00
mem.c drivers/char/mem.c: memory_open() cleanup: lookup minor device number from devlist 2009-06-18 13:03:54 -07:00
misc.c Driver Core: misc: add nodename support for misc devices. 2009-06-15 21:30:25 -07:00
mmtimer.c mmtimer: Push BKL down into the ioctl handler 2008-07-17 11:34:49 -07:00
moxa.c moxa: prevent opening unavailable ports 2009-06-11 08:51:09 -07:00
moxa.h Char: moxa, cleanup rx/tx 2008-04-30 08:29:43 -07:00
mspec.c mspec: convert nopfn to fault 2008-07-24 10:47:14 -07:00
mxser.c tty: Add carrier processing on close to the tty_port core 2009-06-11 08:50:56 -07:00
mxser.h mxser: convert large macros to functions 2008-04-30 08:29:49 -07:00
n_hdlc.c tty: rewrite the ldisc locking 2009-06-11 08:51:01 -07:00
n_r3964.c tty: Remove some pointless casts 2009-01-02 10:19:40 -08:00
n_tty.c tty: simplify buffer allocator cleanups 2009-06-11 08:51:02 -07:00
nozomi.c tty: kref nozomi 2009-01-02 10:19:40 -08:00
nsc_gpio.c [PATCH] struct path: convert char-drivers 2006-12-08 08:28:44 -08:00
nvram.c [PATCH] nvram - convert PRINT_PROC to seq_file 2008-11-11 09:56:00 +00:00
nwbutton.c [PATCH] Char: timers cleanup 2007-02-12 09:48:30 -08:00
nwbutton.h
nwflash.c [ARM] netwinder: clean up GPIO naming 2008-12-13 09:12:07 +00:00
pc8736x_gpio.c pc8736x_gpio: add support for PC87365 chips 2008-10-20 08:52:40 -07:00
ppdev.c ppdev: reduce kernel log spam 2009-06-18 13:03:54 -07:00
ps3flash.c ps3flash: Always read chunks of 256 KiB, and cache them 2009-06-15 16:47:27 +10:00
pty.c pty: Narrow the race on ldisc locking 2009-06-16 12:01:16 -07:00
random.c Avoid ICE in get_random_int() with gcc-3.4.5 2009-05-19 11:25:35 -07:00
raw.c Driver Core: raw: add nodename for raw devices 2009-06-15 21:30:26 -07:00
riscom8_reg.h
riscom8.c riscom8: Auto-load riscom8 module when device opened. 2009-04-06 14:36:31 -07:00
riscom8.h tty: add more tty_port fields 2008-07-20 17:12:38 -07:00
rocket_int.h tty: rocketport uses different port flags to everyone else 2009-01-02 10:19:39 -08:00
rocket.c rocket: fix test_bit parameters 2009-06-11 08:50:58 -07:00
rocket.h tty: rocketport uses different port flags to everyone else 2009-01-02 10:19:39 -08:00
rtc.c RTC: Remove the BKL. 2009-01-08 16:44:03 -07:00
scc.h m68k: atari - Rename "mfp" to "st_mfp" 2009-02-22 09:23:02 -08:00
scx200_gpio.c Add a bunch of cycle_kernel_lock() calls 2008-06-20 14:05:53 -06:00
selection.c tty: rewrite the ldisc locking 2009-06-11 08:51:01 -07:00
ser_a2232.c m68k: ser_a2232 - Kill warn_unused_result warnings 2009-01-12 20:56:39 +01:00
ser_a2232.h
ser_a2232fw.ax
ser_a2232fw.h
serial167.c tty: Remove some pointless casts 2009-01-02 10:19:40 -08:00
snsc_event.c byteorder: don't directly include linux/byteorder/generic.h 2008-05-16 12:01:45 -07:00
snsc.c device create: char: convert device_create_drvdata to device_create 2008-10-16 09:24:42 -07:00
snsc.h Convert asm/semaphore.h users to linux/semaphore.h 2008-04-18 22:22:54 -04:00
sonypi.c Rationalize fasync return values 2009-03-16 08:34:35 -06:00
specialix_io8.h tty: add more tty_port fields 2008-07-20 17:12:38 -07:00
specialix.c specialix: Auto-load specialix module when device opened. 2009-04-06 14:36:31 -07:00
stallion.c tty: Add carrier processing on close to the tty_port core 2009-06-11 08:50:56 -07:00
sx.c sx.c: avoid referencing freed memory if copy_from_user() fails 2009-02-20 17:57:49 -08:00
sx.h Char: char/serial, remove SERIAL_TYPE_NORMAL redefines 2008-02-07 08:42:33 -08:00
sxboards.h
sxwindow.h
synclink_gt.c tty: synclink_gt add receive pio mode 2009-06-11 08:50:57 -07:00
synclink.c tty: Add carrier processing on close to the tty_port core 2009-06-11 08:50:56 -07:00
synclinkmp.c tty: Add carrier processing on close to the tty_port core 2009-06-11 08:50:56 -07:00
sysrq.c kexec: sysrq: simplify sysrq-c handler 2009-06-18 13:03:59 -07:00
tb0219.c Add a bunch of cycle_kernel_lock() calls 2008-06-20 14:05:53 -06:00
tlclk.c tlckl: BKL pushdown 2008-06-20 14:05:51 -06:00
toshiba.c toshiba: use ioremap_cached 2008-04-30 23:15:34 +02:00
tty_audit.c tty: remove buffer special casing 2009-06-11 08:51:02 -07:00
tty_buffer.c tty: split the buffering from tty_io 2008-10-13 09:51:40 -07:00
tty_io.c tty: fix sanity check 2009-06-16 12:01:16 -07:00
tty_ioctl.c tty: fix unused warning when TCGETX is not defined 2009-06-16 12:01:16 -07:00
tty_ldisc.c ldisc: debug aids 2009-06-16 12:01:16 -07:00
tty_port.c tty: use prepare/finish_wait 2009-06-11 08:51:07 -07:00
vc_screen.c vcs: hook sysfs devices into object lifetime instead of "binding" 2009-03-24 16:38:26 -07:00
viotape.c tape: beyond ARRAY_SIZE of viocd_diskinfo 2009-06-02 10:32:34 +10:00
virtio_console.c virtio: find_vqs/del_vqs virtio operations 2009-06-12 22:16:36 +09:30
vme_scc.c m68k: vme_scc - Kill warn_unused_result warnings 2009-01-12 20:56:38 +01:00
vr41xx_giu.c drivers/char: use nr_irqs 2008-10-16 16:52:05 +02:00
vt_ioctl.c vt: Add a note on the historical abuse of CLOCK_TICK_RATE 2009-05-06 14:47:13 -07:00
vt.c console: make blank timeout value a boot option 2009-06-16 19:47:52 -07:00