Commit Graph

62 Commits

Author SHA1 Message Date
Linus Torvalds f579bbcd9b Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  futex: fix requeue_pi key imbalance
  futex: Fix typo in FUTEX_WAIT/WAKE_BITSET_PRIVATE definitions
  rcu: Place root rcu_node structure in separate lockdep class
  rcu: Make hot-unplugged CPU relinquish its own RCU callbacks
  rcu: Move rcu_barrier() to rcutree
  futex: Move exit_pi_state() call to release_mm()
  futex: Nullify robust lists after cleanup
  futex: Fix locking imbalance
  panic: Fix panic message visibility by calling bust_spinlocks(0) before dying
  rcu: Replace the rcu_barrier enum with pointer to call_rcu*() function
  rcu: Clean up code based on review feedback from Josh Triplett, part 4
  rcu: Clean up code based on review feedback from Josh Triplett, part 3
  rcu: Fix rcu_lock_map build failure on CONFIG_PROVE_LOCKING=y
  rcu: Clean up code to address Ingo's checkpatch feedback
  rcu: Clean up code based on review feedback from Josh Triplett, part 2
  rcu: Clean up code based on review feedback from Josh Triplett
2009-10-08 12:16:35 -07:00
Aaro Koskinen d014e8894d panic: Fix panic message visibility by calling bust_spinlocks(0) before dying
Commit ffd71da4e3 ("panic: decrease oops_in_progress only after
having done the panic") moved bust_spinlocks(0) to the end of the
function, which in practice is never reached.

As a result console_unblank() is not called, and on some systems
the user may not see the panic message.

Move it back up to before the unblanking.

Signed-off-by: Aaro Koskinen <aaro.koskinen@nokia.com>
Reviewed-by: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <1254483680-25578-1-git-send-email-aaro.koskinen@nokia.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-05 21:08:09 +02:00
Robert P. J. Day fe002a4197 trivial: Correct print_tainted routine name in comment
Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-09-21 15:14:53 +02:00
Thomas Gleixner bdff78707f trace: stop tracer in oops_enter()
If trace_printk_on_oops is set we lose interesting trace information
when the tracer is enabled across oops handling and printing. We want
the trace which might give us information _WHY_ we oopsed.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-07-24 15:30:45 -04:00
Linus Torvalds 0f6f49a8cd Fix caller information for warn_slowpath_null
Ian Campbell noticed that since "Eliminate thousands of warnings with
gcc 3.2 build" (commit 57adc4d2db) all
WARN_ON()'s currently appear to come from warn_slowpath_null(), eg:

  WARNING: at kernel/softirq.c:143 warn_slowpath_null+0x1c/0x20()

because now that warn_slowpath_null() is in the call path, the
__builtin_return_address(0) returns that, rather than the place that
caused the warning.

Fix this by splitting up the warn_slowpath_null/fmt cases differently,
using a common helper function, and getting the return address in the
right place.  This also happens to avoid the unnecessary stack usage for
the non-stdargs case, and just generally cleans things up.

Make the function name printout use %pS while at it.

Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-05-16 13:41:28 -07:00
Andi Kleen 57adc4d2db Eliminate thousands of warnings with gcc 3.2 build
When building with gcc 3.2 I get thousands of warnings such as

include/linux/gfp.h: In function `allocflags_to_migratetype':
include/linux/gfp.h:105: warning: null format string

due to passing a NULL format string to warn_slowpath() in

#define __WARN()		warn_slowpath(__FILE__, __LINE__, NULL)

Split this case out into a separate call.  This also shrinks the kernel
slightly:

          text    data     bss     dec     hex filename
       4802274  707668  712704 6222646  5ef336 vmlinux
          text    data     bss     dec     hex filename
       4799027  703572  712704 6215303  5ed687 vmlinux

due to removeing one argument from the commonly-called __WARN().

[akpm@linux-foundation.org: reduce scope of `empty']
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-05-06 16:36:09 -07:00
Ingo Molnar b48ccb095a locking: clarify kernel-taint warning message
Andi Kleen reported this message triggering on non-lockdep kernels:

   Disabling lockdep due to kernel taint

Clarify the message to say 'lock debugging' - debug_locks_off()
turns off all things lock debugging, not just lockdep.

[ Impact: change kernel warning message text ]

Reported-by: Andi Kleen <andi@firstfloor.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-04-23 09:36:52 +02:00
Frederic Weisbecker 574bbe7820 lockdep: continue lock debugging despite some taints
Impact: broaden lockdep checks

Lockdep is disabled after any kernel taints. This might be convenient
to ignore bad locking issues which sources come from outside the kernel
tree. Nevertheless, it might be a frustrating experience for the
staging developers or those who experience a warning but are focused
on another things that require lockdep.

The v2 of this patch simply don't disable anymore lockdep in case
of TAINT_CRAP and TAINT_WARN events.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: LTP <ltp-list@lists.sourceforge.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Greg KH <gregkh@suse.de>
LKML-Reference: <1239412638-6739-2-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-04-12 16:10:52 +02:00
Frederic Weisbecker 9eeba6138c lockdep: warn about lockdep disabling after kernel taint
Impact: provide useful missing info for developers

Kernel taint can occur in several situations such as warnings,
load of prorietary or staging modules, bad page, etc...

But when such taint happens, a developer might still be working on
the kernel, expecting that lockdep is still enabled. But a taint
disables lockdep without ever warning about it.
Such a kernel behaviour doesn't really help for kernel development.

This patch adds this missing warning.

Since the taint is done most of the time after the main message that
explain the real source issue, it seems safe to warn about it inside
add_taint() so that it appears at last, without hurting the main
information.

v2: Use a generic helper to disable lockdep instead of an
    open coded xchg().

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <1239412638-6739-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-04-12 16:10:51 +02:00
Ingo Molnar c95dbf27e2 panic: clean up kernel/panic.c
Impact: cleanup, no code changed

Clean up kernel/panic.c some more and make it more consistent.

LKML-Reference: <49B91A7E.76E4.0078.0@novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-13 11:25:53 +01:00
Ingo Molnar d1dedb52ac panic, smp: provide smp_send_stop() wrapper on UP too
Impact: cleanup, no code changed

Remove an ugly #ifdef CONFIG_SMP from panic(), by providing
an smp_send_stop() wrapper on UP too.

LKML-Reference: <49B91A7E.76E4.0078.0@novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-13 11:24:31 +01:00
Ingo Molnar ffd71da4e3 panic: decrease oops_in_progress only after having done the panic
Impact: eliminate secondary warnings during panic()

We can panic() in a number of difficult, atomic contexts, hence
we use bust_spinlocks(1) in panic() to increase oops_in_progress,
which prevents various debug checks we have in place.

But in practice this protection only covers the first few printk's
done by panic() - it does not cover the later attempt to stop all
other CPUs and kexec(). If a secondary warning triggers in one of
those facilities that can make the panic message scroll off.

So do bust_spinlocks(0) only much later in panic(). (which code
is only reached if panic policy is relaxed that it can return
after a warning message)

Reported-by: Jan Beulich <jbeulich@novell.com>
LKML-Reference: <49B91A7E.76E4.0078.0@novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-13 11:06:47 +01:00
Tejun Heo 5d707e9c8e stackprotector: update make rules
Impact: no default -fno-stack-protector if stackp is enabled, cleanup

Stackprotector make rules had the following problems.

* cc support test and warning are scattered across makefile and
  kernel/panic.c.

* -fno-stack-protector was always added regardless of configuration.

Update such that cc support test and warning are contained in makefile
and -fno-stack-protector is added iff stackp is turned off.  While at
it, prepare for 32bit support.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-10 00:41:54 +01:00
Ingo Molnar b2b062b816 Merge branch 'core/percpu' into stackprotector
Conflicts:
	arch/x86/include/asm/pda.h
	arch/x86/include/asm/system.h

Also, moved include/asm-x86/stackprotector.h to arch/x86/include/asm.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-18 18:37:14 +01:00
Arjan van de Ven d6624f996a oops: increment the oops UUID every time we oops
... because we do want repeated same-oops to be seen by automated
tools like kerneloops.org

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:12 -08:00
Ingo Molnar a9de18eb76 Merge branch 'linus' into stackprotector
Conflicts:
	arch/x86/include/asm/pda.h
	kernel/fork.c
2008-12-31 08:31:57 +01:00
Ingo Molnar b594deb0cc Merge branch 'core/debug' into core/core 2008-12-25 13:53:11 +01:00
Arjan van de Ven a800599283 taint: add missing comment
The description for 'D' was missing in the comment...  (causing me a
minute of WTF followed by looking at more of the code)

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-01 19:55:24 -08:00
Ingo Molnar ec5679e513 debug warnings: eliminate warn_on_slowpath()
Impact: cleanup, eliminate code

now that warn_on_slowpath() uses warn_slowpath(...,NULL), we can
eliminate warn_on_slowpath() altogether and use warn_slowpath().

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-28 17:56:14 +01:00
Arjan van de Ven bd89bb29a0 debug warnings: print the DMI board info name in a WARN/WARN_ON
Impact: extend WARN_ON() output with DMI_PRODUCT_NAME

It's very useful for many low level WARN_ON's to find out which
motherboard has the broken BIOS etc... this patch adds a printk
to the WARN_ON code for this.

On architectures without DMI, gcc should optimize the code out.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-28 17:52:50 +01:00
Arjan van de Ven 74853dba2f debug warnings: consolidate warn_slowpath and warn_on_slowpath
Impact: cleanup, code reduction

warn_slowpath is a superset of warn_on_slowpath; just have
warn_on_slowpath call warn_slowpath with a NULL 3rd argument.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-28 17:52:50 +01:00
Rusty Russell f44dd164f3 Make panic= and panic_on_oops into core_params
This allows them to be examined and set after boot, plus means they
actually give errors if they are misused (eg. panic=yes).

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-10-22 10:00:25 +11:00
Linus Torvalds 26e9a39777 Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging-2.6: (25 commits)
  staging: at76_usb wireless driver
  Staging: workaround build system bug
  Staging: Lindent sxg.c
  Staging: SLICOSS: Call pci_release_regions at driver exit
  Staging: SLICOSS: Fix remaining type names
  Staging: SLICOSS: Fix warnings due to static usage
  Staging: SLICOSS: lots of checkpatch fixes
  Staging: go7007 v4l fixes
  Staging: Fix gcc warnings in sxg
  Staging: add echo cancelation module
  Staging: add wlan-ng prism2 usb driver
  Staging: add w35und wifi driver
  Staging: USB/IP: add host driver
  Staging: USB/IP: add client driver
  Staging: USB/IP: add common functions needed
  Staging: add the go7007 video driver
  Staging: add me4000 pci data collection driver
  Staging: add me4000 firmware files
  Staging: add sxg network driver
  Staging: add Alacritech slicoss network driver
  ...

Fixed up conflicts due to taint flags changes and MAINTAINERS cleanup in
MAINTAINERS, include/linux/kernel.h and kernel/panic.c.
2008-10-17 09:50:12 -07:00
Randy Dunlap 6d5cd6effe taint: fix kernel-doc
Move print_tainted() kernel-doc to avoid the following error:

Error(/var/linsrc/mmotm-2008-1002-1617//kernel/panic.c:155): cannot understand prototype: 'struct tnt '

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16 11:21:32 -07:00
Andi Kleen 25ddbb18aa Make the taint flags reliable
It's somewhat unlikely that it happens, but right now a race window
between interrupts or machine checks or oopses could corrupt the tainted
bitmap because it is modified in a non atomic fashion.

Convert the taint variable to an unsigned long and use only atomic bit
operations on it.

Unfortunately this means the intvec sysctl functions cannot be used on it
anymore.

It turned out the taint sysctl handler could actually be simplified a bit
(since it only increases capabilities) so this patch actually removes
code.

[akpm@linux-foundation.org: remove unneeded include]
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16 11:21:31 -07:00
Ingo Molnar b2aaf8f74c Merge branch 'linus' into stackprotector
Conflicts:
	arch/x86/kernel/Makefile
	include/asm-x86/pda.h
2008-10-15 13:46:29 +02:00
Greg Kroah-Hartman 061b1bd394 Staging: add TAINT_CRAP for all drivers/staging code
We need to add a flag for all code that is in the drivers/staging/
directory to prevent all other kernel developers from worrying about
issues here, and to notify users that the drivers might not be as good
as they are normally used to.

Based on code from Andreas Gruenbacher and Jeff Mahoney to provide a
TAINT flag for the support level of a kernel module in the Novell
enterprise kernel release.

This is the kernel portion of this feature, the ability for the flag to
be set needs to be done in the build process and will happen in a
follow-up patch.

Cc: Andreas Gruenbacher <agruen@suse.de>
Cc: Jeff Mahoney <jeffm@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-10-10 15:31:05 -07:00
Arjan van de Ven a8f18b909c Add a WARN() macro; this is WARN_ON() + printk arguments
Add a WARN() macro that acts like WARN_ON(), with the added feature that it
takes a printk like argument that is printed as part of the warning message.

[akpm@linux-foundation.org: fix printk arguments]
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: Greg KH <greg@kroah.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>
2008-07-25 10:53:29 -07:00
Ingo Molnar 4f962d4d65 stackprotector: remove self-test
turns out gcc generates such stackprotector-failure sequences
in certain circumstances:

        movq    -8(%rbp), %rax  # D.16032,
        xorq    %gs:40, %rax    #,
        jne     .L17    #,
        leave
        ret
.L17:
        call    __stack_chk_fail        #
        .size   __stack_chk_test_func, .-__stack_chk_test_func
        .section        .init.text,"ax",@progbits
        .type   panic_setup, @function
panic_setup:
        pushq   %rbp    #

note that there's no jump back to the failing context after the
call to __stack_chk_fail - i.e. it has a ((noreturn)) attribute.

Which is fair enough in the normal case but kills the self-test.
(as we cannot reliably return in the self-test)

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-13 21:50:46 +02:00
Arjan van de Ven af9ff7868f x86: simplify stackprotector self-check
Clean up the code by removing no longer needed code;
make sure the pda is updated and kept in sync

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-13 21:08:38 +02:00
Arjan van de Ven aa92db1427 stackprotector: better self-test
check stackprotector functionality by manipulating the canary briefly
during bootup.

far more robust than trying to overflow the stack. (which is architecture
dependent, etc.)

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-11 20:32:58 +02:00
Arjan van de Ven b40a4392a3 stackprotector: turn not having the right gcc into a #warning
If the user selects the stack-protector config option, but does not have
a gcc that has the right bits enabled (for example because it isn't build
with a glibc that supports TLS, as is common for cross-compilers, but also
because it may be too old), then the runtime test fails right now.

This patch adds a warning message for this scenario. This warning accomplishes
two goals
1) the user is informed that the security option he selective isn't available
2) the user is suggested to turn of the CONFIG option that won't work for him,
   and would make the runtime test fail anyway.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-26 16:15:33 +02:00
Daniel Walker b719ac56c0 panic.c: fix whitespace additions
trivial: remove white space addition in stack protector

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-26 16:15:32 +02:00
Arjan van de Ven 54371a43a6 x86: add CONFIG_CC_STACKPROTECTOR self-test
This patch adds a simple self-test capability to the stackprotector
feature. The test deliberately overflows a stack buffer and then
checks if the canary trap function gets called.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-26 16:15:32 +02:00
Ingo Molnar 5cb273013e panic: print out stacktrace if DEBUG_BUGVERBOSE
if CONFIG_DEBUG_BUGVERBOSE is set then the user most definitely wanted
to see as much information about kernel crashes as possible - so give
them at least a stack dump.

this is particularly useful for stackprotector related panics, where
the stacktrace can give us the exact location of the (attempted)
attack.

Pointed out by pageexec@freemail.hu in the stackprotector breakage
threads.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-26 16:15:32 +02:00
Ingo Molnar 517a92c4e1 panic: print more informative messages on stackprotect failure
pointed out by pageexec@freemail.hu:

we just simply panic() when there's a stackprotector attack - giving
the attacked person no information about what kernel code the attack went
against.

print out the attacked function.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-26 16:15:31 +02:00
Nur Hussein 95b570c9ce Taint kernel after WARN_ON(condition)
The kernel is sent to tainted within the warn_on_slowpath() function, and
whenever a warning occurs the new taint flag 'W' is set.  This is useful to
know if a warning occurred before a BUG by preserving the warning as a flag
in the taint state.

This does not work on architectures where WARN_ON has its own definition.
These archs are:
	1. s390
	2. superh
	3. avr32
	4. parisc

The maintainers of these architectures have been added in the Cc: list
in this email to alert them to the situation.

The documentation in oops-tracing.txt has been updated to include the
new flag.

Signed-off-by: Nur Hussein <nurhussein@gmail.com>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: "Randy.Dunlap" <rdunlap@xenotime.net>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:05:59 -07:00
Éric Piel 6ed31e92e9 ACPI: Taint kernel on ACPI table override (format corrected)
When an ACPI table is overridden (for now this can happen only for DSDT)
display a big warning and taint the kernel with flag A.

Signed-off-by: Eric Piel <eric.piel@tremplin-utc.net>
Signed-off-by: Len Brown <len.brown@intel.com>
2008-02-06 22:07:51 -05:00
Arjan van de Ven 71c339116a debug: add the end-of-trace marker and the module list to
Unlike oopses, WARN_ON() currently does't print the loaded modules list.
This makes it harder to take action on certain bug reports. For example,
recently there were a set of WARN_ON()s reported in the mac80211 stack,
which were just signalling a driver bug. It takes then anther round trip
to the bug reporter (if he responds at all) to find out which driver
is at fault.

Another issue is that, unlike oopses, WARN_ON() doesn't currently printk
the helpful "cut here" line, nor the "end of trace" marker.
Now that WARN_ON() is out of line, the size increase due to this is
minimal and it's worth adding.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:32:50 +01:00
Arjan van de Ven 79b4cc5ee7 debug: move WARN_ON() out of line
A quick grep shows that there are currently 1145 instances of WARN_ON
in the kernel. Currently, WARN_ON is pretty much entirely inlined,
which makes it hard to enhance it without growing the size of the kernel
(and getting Andrew unhappy).

This patch build on top of Olof's patch that introduces __WARN,
and places the slowpath out of line. It also uses Ingo's suggestion
to not use __FUNCTION__ but to use kallsyms to do the lookup;
this saves a ton of extra space since gcc doesn't need to store the function
string twice now:

3936367  833603  624736 5394706  525112 vmlinux.before
3917508  833603  624736 5375847  520767 vmlinux-slowpath

15Kb savings...

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: Olof Johansson <olof@lixom.net>
Acked-by: Matt Meckall <mpm@selenic.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:32:50 +01:00
Arjan van de Ven 2c3b20e91f debug: add end-of-oops marker
Right now it's nearly impossible for parsers that collect kernel crashes
from logs or emails (such as www.kerneloops.org) to detect the
end-of-oops condition. In addition, it's not currently possible to
detect whether or not 2 oopses that look alike are actually the same
oops reported twice, or are truly two unique oopses.

This patch adds an end-of-oops marker, and makes the end marker include
a very simple 64-bit random ID to be able to detect duplicate reports.

Normally, this ID is calculated as a late_initcall() (in the hope that
at that time there is enough entropy to get a unique enough ID); however
for early oopses the oops_exit() function needs to generate the ID on
the fly.

We do this all at the _end_ of an oops printout, so this does not impact
our ability to get the most important portions of a crash out to the
console first.

[ Sidenote: the already existing oopses-since-bootup counter we print
  during crashes serves as the differentiator between multiple oopses
  that trigger during the same bootup. ]

Tested on 32-bit and 64-bit x86. Artificially injected very early
crashes as well, as expected they result in this constant ID after
multiple bootups:

  ---[ end trace ca143223eefdc828 ]---
  ---[ end trace ca143223eefdc828 ]---

because the random pools are still all zero. But it all still works
fine and causes no additional problems (which is the main goal of
instrumentation code).

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-12-20 15:01:17 +01:00
Daniel Roesen 9aa5e993fa trivial comment wording/typo fix regarding taint flags
Signed-off-by: Daniel Roesen <dr@cluenet.de>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
2007-10-20 00:30:06 +02:00
Daniel Walker c277e63fbe whitespace fixes: panic handling
Signed-off-by: Daniel Walker <dwalker@mvista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-18 14:37:25 -07:00
Pavel Emelianov bcdcd8e725 Report that kernel is tainted if there was an OOPS
If the kernel OOPSed or BUGed then it probably should be considered as
tainted.  Thus, all subsequent OOPSes and SysRq dumps will report the
tainted kernel.  This saves a lot of time explaining oddities in the
calltraces.

Signed-off-by: Pavel Emelianov <xemul@openvz.org>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
[ Added parisc patch from Matthew Wilson  -Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-17 10:23:02 -07:00
Theodore Ts'o 34f5a39899 [PATCH] Add TAINT_USER and ability to set taint flags from userspace
Allow taint flags to be set from userspace by writing to
/proc/sys/kernel/tainted, and add a new taint flag, TAINT_USER, to be used
when userspace has potentially done something dangerous that might
compromise the kernel.  This will allow support personnel to ask further
questions about what may have caused the user taint flag to have been set.

For example, they might examine the logs of the realtime JVM to see if the
Java program has used the really silly, stupid, dangerous, and
completely-non-portable direct access to physical memory feature which MUST
be implemented according to the Real-Time Specification for Java (RTSJ).
Sigh.  What were those silly people at Sun thinking?

[akpm@osdl.org: build fix]
[bunk@stusta.de: cleanup]
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11 10:51:29 -08:00
Andi Kleen 29cbc78b90 [PATCH] x86: Clean up x86 NMI sysctls
Use prototypes in headers
Don't define panic_on_unrecovered_nmi for all architectures

Cc: dzickus@redhat.com

Signed-off-by: Andi Kleen <ak@suse.de>
2006-09-30 01:47:55 +02:00
Arjan van de Ven 3162f751d0 [PATCH] Add the __stack_chk_fail() function
GCC emits a call to a __stack_chk_fail() function when the stack canary is
not matching the expected value.

Since this is a bad security issue; lets panic the kernel rather than limping
along; the kernel really can't be trusted anymore when this happens.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andi Kleen <ak@suse.de>
CC: Andi Kleen <ak@suse.de>
2006-09-26 10:52:39 +02:00
Don Zickus 8da5adda91 [PATCH] x86: Allow users to force a panic on NMI
To quote Alan Cox:

The default Linux behaviour on an NMI of either memory or unknown is to
continue operation. For many environments such as scientific computing
it is preferable that the box is taken out and the error dealt with than
an uncorrected parity/ECC error get propogated.

A small number of systems do generate NMI's for bizarre random reasons
such as power management so the default is unchanged. In other respects
the new proc/sys entry works like the existing panic controls already in
that directory.

This is separate to the edac support - EDAC allows supported chipsets to
handle ECC errors well, this change allows unsupported cases to at least
panic rather than cause problems further down the line.

Signed-off-by: Don Zickus <dzickus@redhat.com>
Signed-off-by: Andi Kleen <ak@suse.de>
2006-09-26 10:52:27 +02:00
Ingo Molnar 068c4579fe [PATCH] lockdep: do not touch console state when tainting the kernel
Remove an unintended console_verbose() side-effect from add_taint().

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-06 11:00:02 -07:00
Andrew Morton 657b3010d8 [PATCH] panic.c build fix
kernel/panic.c: In function 'add_taint':
kernel/panic.c:176: warning: implicit declaration of function 'debug_locks_off'

Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-08-14 12:54:28 -07:00