* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6: (35 commits)
V4L/DVB (9516): cx18: Move DVB buffer transfer handling from irq handler to work_queue
V4L/DVB (9557): gspca: Small changes for the sensor HV7131B in zc3xx.
V4L/DVB (9556): gspca: Bad init sequence for sensor HV7131B in zc3xx.
V4L/DVB (9549): gspca: Fix a typo in one of gspca chips name.
V4L/DVB (9515): cx18: Use correct Mailbox IRQ Ack values and misc IRQ handling cleanup
V4L/DVB (9493): kconfig patch
V4L/DVB (9527): af9015: fix compile warnings
V4L/DVB (9524): af9013: fix bug in status reading
V4L/DVB (9511): cx18: Mark CX18_CPU_DE_RELEASE_MDL as a slow API call
V4L/DVB (9510): cx18: Fix write retries for registers that always change - part 2.
V4L/DVB (9506): ivtv/cx18: fix test whether modules should be loaded or not.
V4L/DVB (9499): cx88-mpeg: final fix for analogue only compilation + de-alloc fix
V4L/DVB (9496): cx88-blackbird: bugfix: cx88-blackbird-mpeg-users
V4L/DVB (9495): cx88-blackbird: bugfix: cx88-blackbird-poll-fix
V4L/DVB (9494): anysee: initialize anysee_usb_mutex statically
V4L/DVB (9492): unplug oops from dvb_frontend_init...
V4L/DVB (9486): ivtv/ivtvfb: no longer experimental
V4L/DVB (9485): ivtv: remove incorrect V4L1 & tvaudio dependency
V4L/DVB (9482): Documentation, especially regarding audio and informational links
V4L/DVB (9475): cx18: Disable write retries for registers that always change - part 1.
...
* 'drm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6:
drm/i915: Move legacy breadcrumb out of the reserved status page area
drm/i915: Filter pci devices based on PCI_CLASS_DISPLAY_VGA
drm/radeon: map registers at load time
drm: Remove infrastructure for supporting i915's vblank swapping.
i915: Remove racy delayed vblank swap ioctl.
i915: Don't whine when pci_enable_msi() fails.
i915: Don't attempt to short-circuit object_wait_rendering by checking domains.
i915: Clean up sarea pointers on leavevt
i915: Save/restore MCHBAR_RENDER_STANDBY on GM965/GM45
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6:
dsa: fix master interface allmulti/promisc handling
dsa: fix skb->pkt_type when mac address of slave interface differs
net: fix setting of skb->tail in skb_recycle_check()
net: fix /proc/net/snmp as memory corruptor
mac80211: fix a buffer overrun in station debug code
netfilter: payload_len is be16, add size of struct rather than size of pointer
ipv6: fix ip6_mr_init error path
[4/4] dca: fixup initialization dependency
[3/4] I/OAT: fix async_tx.callback checking
[2/4] I/OAT: fix dma_pin_iovec_pages() error handling
[1/4] I/OAT: fix channel resources free for not allocated channels
ssb: Fix DMA-API compilation for non-PCI systems
SSB: hide empty sub menu
vlan: Fix typos in proc output string
[netdrvr] usb/hso: Cleanup rfkill error handling
sfc: Correct address of gPXE boot configuration in EEPROM
el3_common_init() should be __devinit, not __init
hso: rfkill type should be WWAN
mlx4_en: Start port error flow bug fix
af_key: mark policy as dead before destroying
fix:
arch/x86/kernel/ftrace.c: In function 'ftrace_return_to_handler':
arch/x86/kernel/ftrace.c:112: error: implicit declaration of function 'cpu_clock'
cpu_clock() is implicitly included via a number of ways, but its real
location is sched.h. (Build failure is triggerable if enough other
kernel components are turned off.)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Clear buddies on yield, so that the buddy rules don't schedule them
despite them being placed right-most.
This fixed a performance regression with yield-happy binary JVMs.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Tested-by: Lin Ming <ming.m.lin@intel.com>
fix:
arch/x86/kernel/ftrace.c: Assembler messages:
arch/x86/kernel/ftrace.c:140: Error: missing ')'
arch/x86/kernel/ftrace.c:140: Error: junk `(%ebp))' after expression
arch/x86/kernel/ftrace.c:141: Error: missing ')'
arch/x86/kernel/ftrace.c:141: Error: junk `(%ebp))' after expression
the [parent_replaced] is used in an =rm fashion, so that constraint
is correct in isolation - but [parent_old] aliases register %0 and uses
it in an addressing mode that is only valid with registers - so change
the constraint from =rm to =r.
This fixes the build failure.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
cx18: Move DVB buffer transfer handling from irq handler to work_queue thread.
In order to properly lock the epu2cpu mailbox for driver to CX23418 commands,
the DVB/TS buffer handling needs to be moved from the IRQ handler and IRQ
context to a work queue. This work_queue implmentation is strikingly similar
to the ivtv implementation - for better or worse.
Signed-off-by: Andy Walls <awalls@radix.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
- touch only one register for brightness change
- no quality control
- don't probe again at streamon time.
Signed-off-by: Jean-Francois Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This patch fixes the H flip and the R & B color inversion of mode 320x240.
Signed-off-by: Jean-Francois Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
cx18: Use correct Mailbox IRQ Ack values and misc IRQ handling cleanup.
The SCB field definitions for Ack IRQ's for mailboxes were inconsistent with
the bitmasks being loaded into those SCB fields and the SW2 Ack IRQ handling
logic. Renamed fields in SCB to make things consistent and did misc IRQ
handling cleanups: removing legacy ivtv dma_reg_lock, HPU IRQ flags, etc.
Signed-off-by: Andy Walls <awalls@radix.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Ok I made a patch that converts gspca kconfig file to a more standard=
one, with tabs + 2 white spaces, so that if a warning is added it still
compiles
please find it attached
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
cx18: Mark CX18_CPU_DE_RELEASE_MDL as a slow API call.
Give the encoder time to complete the MDL release before destroying the
encoder internal task. This avoids an encoder lockup on the next digital
capture and error messages about buffers being returned for an inactive
encoder task handle.
Signed-off-by: Andy Walls <awalls@radix.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
cx18: Fix write retries for registers that always change - part 2.
Some registers, especially interrupt related ones, will never read
back the value just written. Modified interrupt register readback
checks to make sure the intended effect was achieved.
Signed-off-by: Andy Walls <awalls@radix.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Final fix for when analogue only is selected
for compilation (ie, !CX88_DVB)
This tidies up previous fix and adds missing
de-alloc memory leak on fault (eg, if fe1 fails to alloc
where fe0 was allocated).
Signed-off-by: Darron Broad <darron@kewl.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Starts encoder not only on a read call but also on a poll command.
Signed-off-by: Frederic CAND <frederic.cand@anevia.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
anysee_usb_mutex is initialized at every time the anysee device is probed.
If the second anysee device is probed while anysee_usb_mutex is locked by
the first anysee device, the mutex is broken.
This patch fixes by initialize anysee_usb_mutex statically rather
than initialize at probe time.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
ivtv used tvaudio in the past and at the time tvaudio required V4L1.
Since tvaudio is no longer dependent on V4L1 and since ivtv actually
no longer uses tvaudio at all, this is no removed from Kconfig.
Without this patch ivtv won't be build if V4L1 is disabled.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This patch adds a recommendation to select SND_USB_AUDIO for listing and
adds a documentation file for si470x.
Signed-off-by: Tobias Lorenz <tobias.lorenz@gmx.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
cx18: Disable write retries for registers that always change - part 1.
Interrupt related registers will likely not read back the value we just wrote.
Disable retries for these registers for now to avoid accidently discarding
interrupts. More intelligent read back verification criteria are needed for
these and other registers (e.g. GPIO line registers), which will be addressed in
subsequent changes.
Signed-off-by: Andy Walls <awalls@radix.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
* Apparently the author of the saa7110 driver was confused by the
number of outputs returned by DECODER_GET_CAPABILITIES. Of course a
decoder chip has no analog ouputs, but it must have at least one
digital output.
* Fix an off-by-one error when checking the input value of
DECODER_SET_INPUT.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Attached is a patch that updates the cx88 documentation to add the fact the
closed caption works for at least NTSC capture.
ps: I also updated the wiki at:
http://www.linuxtv.org/v4lwiki/index.php/Text_capture#cx88_devices
Signed-off-by: Rafael Diniz <diniz@wimobilis.com.br>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
The attached patch fix VBI support cx88 card.
I'm running a capture for hours, getting the closed caption from it[1], and
it's working perfect - the output is the same of a bttv card.
Please apply this patch as soon as possible.
[1] - using zvbi-ntsc-cc of zvbi project.
Signed-off-by: Rafael Diniz <diniz@wimobilis.com.br>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
config\tDVB_USB_CINERGY_T2 causes the make_kconfig.pl to forget to enable by default the compilation of cinergyT2 module.
Signed-off-by: Thierry MERLE <thierry.merle@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
There already is an report at kernel bugzilla about this issue:
http://bugzilla.kernel.org/show_bug.cgi?id=9455
When enabling extra checks for the i2c-bus of cx88 based cards by
loading i2c_algo_bit with bit_test=1 this may trigger an oops
when loading cx88_dvb.
This is caused by the extra check code that detects that the
sda-line is stuck high and thus does not register the i2c-bus.
cx88-dvb however does not check if the i2c-bus is valid and just
uses core->i2c_adap to attach dvb frontend modules.
This leads to an oops at the first call to i2c_transfer:
$ modprobe i2c_algo_bit bit_test=1
$ modprobe cx8802
cx88/2: cx2388x MPEG-TS Driver Manager version 0.0.6 loaded
cx88[0]: quirk: PCIPCI_NATOMA -- set TBFX
cx88[0]: subsystem: 0070:9202, board: Hauppauge Nova-S-Plus DVB-S [card=37,autodetected], frontend(s): 1
cx88[0]: TV tuner type 4, Radio tuner type -1
cx88[0]: SDA stuck high!
cx88[0]: i2c register FAILED
input: cx88 IR (Hauppauge Nova-S-Plus as /class/input/input5
cx88[0]/2: cx2388x 8802 Driver Manager
cx88-mpeg driver manager 0000:00:10.2: enabling device (0154 -> 0156)
cx88-mpeg driver manager 0000:00:10.2: PCI INT A -> Link[LNKD] -> GSI 9 (level, low) -> IRQ 9
cx88[0]/2: found at 0000:00:10.2, rev: 5, irq: 9, latency: 64, mmio: 0xfb000000
cx8802_probe() allocating 1 frontend(s)
cx88/2: cx2388x dvb driver version 0.0.6 loaded
cx88/2: registering cx8802 driver, type: dvb access: shared
cx88[0]/2: subsystem: 0070:9202, board: Hauppauge Nova-S-Plus DVB-S [card=37]
cx88[0]/2: cx2388x based DVB/ATSC card
BUG: unable to handle kernel NULL pointer dereference at 00000000
IP: [<e084d4ef>] :i2c_core:i2c_transfer+0x1f/0x80
*pde = 00000000
Modules linked in: cx88_dvb(+) cx8802 cx88xx ir_common i2c_algo_bit tveeprom videobuf_dvb btcx_risc
mga drm ipv6 fscpos eeprom nfsd exportfs stv0299 b2c2_flexcop_pci b2c2_flexcop cx24123 s5h1420 ves1x93
dvb_ttpci dvb_core saa7146_vv saa7146 videobuf_dma_sg videobuf_core videodev v4l1_compat ttpci_eeprom
lirc_serial lirc_dev usbhid rtc uhci_hcd 8139too i2c_piix4 i2c_core usbcore evdev
Pid: 4249, comm: modprobe Not tainted (2.6.27-gentoo #3)
EIP: 0060:[<e084d4ef>] EFLAGS: 00010296 CPU: 0
EIP is at i2c_transfer+0x1f/0x80 [i2c_core]
EAX: 00000000 EBX: ffffffa1 ECX: 00000002 EDX: d6c71e3c
ESI: d80cd050 EDI: d8093c00 EBP: d6c71e20 ESP: d6c71e0c
DS: 007b ES: 007b FS: 0000 GS: 0033 SS: 0068
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Impact: driver could possibly stomp on resources outside of its scope
{mchehab@redhat.com: I got two versions of the same patch (identical,
except for whitespacing). One authored by Andy Burns and another
authored by Suresh Siddha. Due to that, I'm applying the one that has
less CodingStyle errors. I'm also adding both comments and the SOB's for
both patches, since they are both interesting}
Suresh Siddha commented:
Alexey Fisher reported:
> resource map sanity check conflict: 0xcfeff800 0xcff007ff 0xcfe00000
> 0xcfefffff PCI Bus 0000:01
BAR base is located in the middle of the 4K page and the hardcoded
size argument makes the request span two pages causing the conflict.
Fix the hard coded size argument in ioremap().
Andy Burns commented:
I have already sent this patch on the linux-dvb list, but it didn't get
much attention, so re-sending direct, I hope you all don't mind.
While attempting to run mythtv in a xen domU, I encountered problems
loading the driver for my saa7134 card, with an error from ioremap().
This error was due to the driver allocating an incorrectly sized mmio
area, which was trapped by xen's permission checks, but this would go
un-noticed on a kernel without xen.
My card has a 1K sized mmio area, I've had information that other cards
have 2K areas, perhaps others have different sizes, yet the driver
always attempts to map 4K. I realise that the granularity of mapping is
the page size, which typically would be 4K, but unless the card's base
address happens to fall on a 4K boundary (mine does not) then the
base+4K will end up spanning two pages, and this is when the error
occurs under xen.
My patch uses the pci_resource_len macro to determine the size required
for the user's particular card, instead of the hardcoded 4K value. I've
tested with a couple of printk() inside ioremap() that the start address
and size do get rounded to the closest page boundary.
With this patch I am able to successfully load the saa7134 driver and
run mythtv under xen with my card, subject to correct pollirq settings
in case of shared IRQ, I am still seeing occasional DMA panics, which I
think are related to swiotlb handling by dom0/domU, usually the panic
occurs when changing mux, once tuned to a mux, 12 hour continuous
recordings are possible without errors.
Reported-by: Alexey Fisher <bug-track@fisher-privat.net>
Tested-by: Alexey Fisher <bug-track@fisher-privat.net>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Andy Burns <andy@burns.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Remove lock_kernel() call from cafe_ccic.c
Commit d56dc61265 added lock_kernel()
calls to cafe_ccic.c. But that driver was written with proper locking
and does not need the BKL, so take it back out.
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This patch adds the missing compat ioctls that are needed to
operate Skype in combination with libv4l and a MJPEG only camera.
If you think it's trivial enough please submit it to -stable, too.
Signed-off-by: Gregor Jasny <gjasny@web.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
As reported by David Ellingsworth:
> I'm not sure if it matters or not, but the ibmcam driver in the
> Mauro's linux-2.6 git tree in the for_linus branch is currently
> broken.
uvd is equal to NULL during most of ibmcam_probe. Due to that, an OOPS is
generated at dev_info. This patch replaces uvd->dev->dev to dev->dev
inside this routine.
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Reviewed-by: David Ellingsworth <david@identd.dyndns.org>
This patch add support for new device named KWorld USB FM Radio
SnapMusic Mobile 700 (FM700).
And changes few lines in comments.
Signed-off-by: Alexey Klimov <klimov.linux@gmail.com>
Acked-by: Tobias Lorenz <tobias.lorenz@gmx.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Update Kconfig to add missing dependency on zl10353 for dtv5100 driver.
Signed-off-by: Antoine Jacquet <royale@zerezo.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
rather than implementing different ways leading to confusion.
This allows multiple gate_enable/disable's in the tuner_read/write
functions, thereby lesser number of I/O operations throughout,
eventually leading to better results. As a side effect demods that
detect the STOP bit for auto closing of the gate can be avoided, thereby
a very minimal gain in disabling the auto detect feature as well.
Improves readability on the device control.
Signed-off-by: Manu Abraham <manu@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
The tuner-3036 and dpc7146 drivers have been deleted now so we can
remove the corresponding entries from feature-removal-schedule.txt.
(Thanks for doing this, BTW.)
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This device is already handled by radio-si470x driver, and we
therefore want usbhid to ignore it.
Signed-off-by: Alexey Klimov <klimov.linux@gmail.com>
Acked-by: Tobias Lorenz <tobias.lorenz@gmx.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Impact: fix incorrect locking triggered during hotplug-intense stress-tests
While migrating the the CB_IRQSAFE_UNLOCKED timers during a cpu-offline,
we queue them on the cb_pending list, so that they won't go
stale.
Thus, when the callbacks of the timers run from the softirq context,
they could run into potential deadlocks, since these callbacks
assume that they're running with irq's disabled, thereby annoying
lockdep!
Fix this by emulating hardirq context while running these callbacks from
the hrtimer softirq.
=================================
[ INFO: inconsistent lock state ]
2.6.27 #2
--------------------------------
inconsistent {in-hardirq-W} -> {hardirq-on-W} usage.
ksoftirqd/0/4 [HC0[0]:SC1[1]:HE1:SE0] takes:
(&rq->lock){++..}, at: [<c011db84>] sched_rt_period_timer+0x9e/0x1fc
{in-hardirq-W} state was registered at:
[<c014103c>] __lock_acquire+0x549/0x121e
[<c0107890>] native_sched_clock+0x88/0x99
[<c013aa12>] clocksource_get_next+0x39/0x3f
[<c0139abc>] update_wall_time+0x616/0x7df
[<c0141d6b>] lock_acquire+0x5a/0x74
[<c0121724>] scheduler_tick+0x3a/0x18d
[<c047ed45>] _spin_lock+0x1c/0x45
[<c0121724>] scheduler_tick+0x3a/0x18d
[<c0121724>] scheduler_tick+0x3a/0x18d
[<c012c436>] update_process_times+0x3a/0x44
[<c013c044>] tick_periodic+0x63/0x6d
[<c013c062>] tick_handle_periodic+0x14/0x5e
[<c010568c>] timer_interrupt+0x44/0x4a
[<c0150c9f>] handle_IRQ_event+0x13/0x3d
[<c0151c14>] handle_level_irq+0x79/0xbd
[<c0105634>] do_IRQ+0x69/0x7d
[<c01041e4>] common_interrupt+0x28/0x30
[<c047007b>] aac_probe_one+0x1a3/0x3f3
[<c047ec2d>] _spin_unlock_irqrestore+0x36/0x39
[<c01512b4>] setup_irq+0x1be/0x1f9
[<c065d70b>] start_kernel+0x259/0x2c5
[<ffffffff>] 0xffffffff
irq event stamp: 50102
hardirqs last enabled at (50102): [<c047ebf4>] _spin_unlock_irq+0x20/0x23
hardirqs last disabled at (50101): [<c047edc2>] _spin_lock_irq+0xa/0x4b
softirqs last enabled at (50088): [<c0128ba6>] do_softirq+0x37/0x4d
softirqs last disabled at (50099): [<c0128ba6>] do_softirq+0x37/0x4d
other info that might help us debug this:
no locks held by ksoftirqd/0/4.
stack backtrace:
Pid: 4, comm: ksoftirqd/0 Not tainted 2.6.27 #2
[<c013f6cb>] print_usage_bug+0x13e/0x147
[<c013fef5>] mark_lock+0x493/0x797
[<c01410b1>] __lock_acquire+0x5be/0x121e
[<c0141d6b>] lock_acquire+0x5a/0x74
[<c011db84>] sched_rt_period_timer+0x9e/0x1fc
[<c047ed45>] _spin_lock+0x1c/0x45
[<c011db84>] sched_rt_period_timer+0x9e/0x1fc
[<c011db84>] sched_rt_period_timer+0x9e/0x1fc
[<c01210fd>] finish_task_switch+0x41/0xbd
[<c0107890>] native_sched_clock+0x88/0x99
[<c011dae6>] sched_rt_period_timer+0x0/0x1fc
[<c0136dda>] run_hrtimer_pending+0x54/0xe5
[<c011dae6>] sched_rt_period_timer+0x0/0x1fc
[<c0128afb>] __do_softirq+0x7b/0xef
[<c0128ba6>] do_softirq+0x37/0x4d
[<c0128c12>] ksoftirqd+0x56/0xc5
[<c0128bbc>] ksoftirqd+0x0/0xc5
[<c0134649>] kthread+0x38/0x5d
[<c0134611>] kthread+0x0/0x5d
[<c0104477>] kernel_thread_helper+0x7/0x10
=======================
Signed-off-by: Gautham R Shenoy <ego@in.ibm.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: add new tracing plugin which can trace full (entry+exit) function calls
This tracer uses the low level function return ftrace plugin to
measure the execution time of the kernel functions.
The first field is the caller of the function, the second is the
measured function, and the last one is the execution time in
nanoseconds.
- v3:
- HAVE_FUNCTION_RET_TRACER have been added. Each arch that support ftrace return
should enable it.
- ftrace_return_stub becomes ftrace_stub.
- CONFIG_FUNCTION_RET_TRACER depends now on CONFIG_FUNCTION_TRACER
- Return traces printing can be used for other tracers on trace.c
- Adapt to the new tracing API (no more ctrl_update callback)
- Correct the check of "disabled" during insertion.
- Minor changes...
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: add infrastructure for function-return tracing
Add low level support for ftrace return tracing.
This plug-in stores return addresses on the thread_info structure of
the current task.
The index of the current return address is initialized when the task
is the first one (init) and when a process forks (the child). It is
not needed when a task does a sys_execve because after this syscall,
it still needs to return on the kernel functions it called.
Note that the code of return_to_handler has been suggested by Steven
Rostedt as almost all of the ideas of improvements in this V3.
For purpose of security, arch/x86/kernel/process_32.c is not traced
because __switch_to() changes the current task during its execution.
That could cause inconsistency in the stored return address of this
function even if I didn't have any crash after testing with tracing on
this function enabled.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Alan Cox