The tracing_on/off() declarations were under CONFIG_RING_BUFFER, but
the functions are now only defined under CONFIG_TRACING as they are
specific to ftrace and not the ring buffer.
But the declarations were still defined under the ring buffer and
this caused the build to fail when CONFIG_RING_BUFFER was set but
CONFIG_TRACING was not.
Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
When a machine boots up, the TSC generally gets reset. However,
when kexec is used to boot into a kernel, the TSC value would be
carried over from the previous kernel. The computation of
cycns_offset in set_cyc2ns_scale is prone to an overflow, if the
machine has been up more than 208 days prior to the kexec. The
overflow happens when we multiply *scale, even though there is
enough room to store the final answer.
We fix this issue by decomposing tsc_now into the quotient and
remainder of division by CYC2NS_SCALE_FACTOR and then performing
the multiplication separately on the two components.
Refactor code to share the calculation with the previous
fix in __cycles_2_ns().
Signed-off-by: Salman Qazi <sqazi@google.com>
Acked-by: John Stultz <john.stultz@linaro.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Turner <pjt@google.com>
Cc: john stultz <johnstul@us.ibm.com>
Link: http://lkml.kernel.org/r/20120310004027.19291.88460.stgit@dungbeetle.mtv.corp.google.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This header isn't using bug.h infrastructure, but due to historical
reasons, it was including it. Removing it revealed several implicit
dependencies (since kernel.h is everywhere) so we've fixed those 1st
before deploying this change.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
The support for BUILD_BUG in linux/kernel.h predates the
addition of linux/bug.h -- with this chunk off separate,
you can run into situations where a person gets a compile
fail even when they've included linux/bug.h, like this:
CC lib/string.o
lib/string.c: In function 'strlcat':
lib/string.c:225:2: error: implicit declaration of function 'BUILD_BUG_ON'
make[2]: *** [lib/string.o] Error 1
$
$ grep linux/bug.h lib/string.c
#include <linux/bug.h>
$
Since the above violates the principle of least surprise, move
the BUG chunks from kernel.h to bug.h so it is all together.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
* 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, reboot: Fix typo in nmi reboot path
x86, NMI: Add to_cpumask() to silence compile warning
x86, NMI: NMI selftest depends on the local apic
x86: Add stack top margin for stack overflow checking
x86, NMI: NMI-selftest should handle the UP case properly
x86: Fix the 32-bit stackoverflow-debug build
x86, NMI: Add knob to disable using NMI IPIs to stop cpus
x86, NMI: Add NMI IPI selftest
x86, reboot: Use NMI instead of REBOOT_VECTOR to stop cpus
x86: Clean up the range of stack overflow checking
x86: Panic on detection of stack overflow
x86: Check stack overflow in detail
We can place this in definitions that we expect the compiler to remove by
dead code elimination. If this assertion fails, we get a nice error
message at build time.
The GCC function attribute error("message") was added in version 4.3, so
we define a new macro __linktime_error(message) to expand to this for
GCC-4.3 and later. This will give us an error diagnostic from the
compiler on the line that fails. For other compilers
__linktime_error(message) expands to nothing, and we have to be content
with a link time error, but at least we will still get a build error.
BUILD_BUG() expands to the undefined function __build_bug_failed() and
will fail at link time if the compiler ever emits code for it. On GCC-4.3
and later, attribute((error())) is used so that the failure will be noted
at compile time instead.
Signed-off-by: David Daney <david.daney@cavium.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: DM <dm.n9107@gmail.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently, messages are just output on the detection of stack
overflow, which is not sufficient for systems that need a
high reliability. This is because in general the overflow may
corrupt data, and the additional corruption may occur due to
reading them unless systems stop.
This patch adds the sysctl parameter
kernel.panic_on_stackoverflow and causes a panic when detecting
the overflows of kernel, IRQ and exception stacks except user
stack according to the parameter. It is disabled by default.
Signed-off-by: Mitsuo Hayasaka <mitsuo.hayasaka.hu@hitachi.com>
Cc: yrl.pp-manager.tt@hitachi.com
Cc: Randy Dunlap <rdunlap@xenotime.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Link: http://lkml.kernel.org/r/20111129060836.11076.12323.stgit@ltc219.sdl.hitachi.co.jp
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Use of the GPL or a compatible licence doesn't necessarily make the code
any good. We already consider staging modules to be suspect, and this
should also be true for out-of-tree modules which may receive very
little review.
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Reviewed-by: Dave Jones <davej@redhat.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (patched oops-tracing.txt)
Mark obsolete/deprecated strict_strto<foo> and simple_strto<foo> functions
and macros as obsolete.
Update checkpatch to warn about their use.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
hex2bin converts a hexadecimal string to its binary representation.
The original version of hex2bin did not do any error checking. This
patch adds error checking and returns the result.
Changelog v1:
- removed unpack_hex_byte()
- changed return code from boolean to int
Changelog:
- use the new unpack_hex_byte()
- add __must_check compiler option (Andy Shevchenko's suggestion)
- change function API to return error checking result
(based on Tetsuo Handa's initial patch)
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>
* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending:
target: Convert to DIV_ROUND_UP_SECTOR_T usage for sectors / dev_max_sectors
kernel.h: Add DIV_ROUND_UP_ULL and DIV_ROUND_UP_SECTOR_T macro usage
iscsi-target: Add iSCSI fabric support for target v4.1
iscsi: Add Serial Number Arithmetic LT and GT into iscsi_proto.h
iscsi: Use struct scsi_lun in iscsi structs instead of u8[8]
iscsi: Resolve iscsi_proto.h naming conflicts with drivers/target/iscsi
Add new DIV_ROUND_UP_SECTOR_T macro usage for 32-bit architectures requiring
a new DIV_ROUND_UP_ULL, and existing 64-bit usage with DIV_ROUND_UP.
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
Fix the warning:
usr/include/linux/kernel.h:65: userspace cannot reference function or variable defined in the kernel
As Michal noted, BUILD_BUG_ON stuffs should be moved
under #ifdef __KERNEL__.
Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com>
Cc: Michal Marek <mmarek@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The sleeping inside spinlock detection is actually used
for more general sleeping inside atomic sections
debugging: preemption disabled, rcu read side critical
sections, interrupts, interrupt disabled, etc...
Change the name of the config and its help section to
reflect its more general role.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@elte.hu>
There is quite a lot of code which does copy_from_user() + strict_strto*()
or simple_strto*() combo in slightly different ways.
Before doing conversions all over tree, let's get final API correct.
Enter kstrtoull_from_user() and friends.
Typical code which uses them looks very simple:
TYPE val;
int rv;
rv = kstrtoTYPE_from_user(buf, count, 0, &val);
if (rv < 0)
return rv;
[use val]
return count;
There is a tiny semantic difference from the plain kstrto*() API -- the
latter allows any amount of leading zeroes, while the former copies data
into buffer on stack and thus allows leading zeroes as long as it fits
into buffer.
This shouldn't be a problem for typical usecase "echo 42 > /proc/x".
The point is to make reading one integer from userspace _very_ simple and
very bug free.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
