Impact: fix failure of dynamic function tracer selftest
In a course of development, a developer does several makes on their
kernel. Sometimes, the make might do something abnormal. In the
case of running the recordmcount.pl script on an object twice,
the script will duplicate all the calls to mcount in the __mcount_loc
section.
On boot up, the dynamic function tracer is careful when it modifies
code, and performs several consistency checks. One is to not modify
the call site if it is not what it expects it to be. If a function
call site is listed twice, the first entry will convert the site
to a nop, and the second will fail because it expected to see a
call to mcount, but instead it sees a nop. Thus, the function tracer
is disabled.
Eric Sesterhenn reported seeing:
[ 1.055440] ftrace: converting mcount calls to 0f 1f 44 00 00
[ 1.055568] ftrace: allocating 29418 entries in 116 pages
[ 1.061000] ------------[ cut here ]------------
[ 1.061000] WARNING: at kernel/trace/ftrace.c:441
[...]
[ 1.060000] ---[ end trace 4eaa2a86a8e2da23 ]---
[ 1.060000] ftrace failed to modify [<c0118072>] check_corruption+0x3/0x2d
[ 1.060000] actual: 0f:1f:44:00:00
This warning shows that check_corruption+0x3 already had a nop in
its place (0x0f1f440000). After compiling another kernel the problem
went away.
Later Eric Paris notice the same type of issue. Luckily, he saved
the vmlinux file that caused it. In the file we found a bunch of
duplicate mcount call site records, which lead us to the script.
Perhaps this problem only happens to people named Eric.
This patch changes the script to test if the __mcount_loc already
exists in the object file, and if it does, it will print out
an error message and kill the compile.
Reported-by: Eric Sesterhenn <snakebyte@gmx.de>
Reported-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
We should not be continuing a braced section with an if, for example:
if (...) {
} if (...) {
}
Detect this and suggest adding a newline.
Signed-off-by: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When we allow return to have surrounding parentheses when containing
comparison operators we are not correctly handling the case where the
values contain array sufffixes. Squash them.
Signed-off-by: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We should not be complaining about the prefix spacing for types and casts.
We are triggering here because the check for spacing between '*'s is
overly loose. Tighten this up.
Signed-off-by: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This reverts commit ad7a953c52.
And commit: ("allow stripping of generated symbols under CONFIG_KALLSYMS_ALL")
9bb482476c
These stripping patches has caused a set of issues:
1) People have reported compatibility issues with binutils due to
lack of support for `--strip-unneeded-symbols' with objcopy 2.15.92.0.2
Reported by: Wenji
2) ccache and distcc no longer works as expeced
Reported by: Ted, Roland, + others
3) The installed modules increased a lot in size
Reported by: Ted, Davej + others
Reported-by: Wenji Huang <wenji.huang@oracle.com>
Reported-by: "Theodore Ts'o" <tytso@mit.edu>
Reported-by: Dave Jones <davej@redhat.com>
Reported-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
In IA64, a function pointer isn't a 'unsigned long' but a
'struct {unsigned long ip, unsigned long gp}'. MCOUNT_ADDR is determined
at link time not compile time, so explictly ignore kernel/trace/ftrace.o
in recordmcount.pl.
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
In IA64, module build and kernel build use different option.
Make recordmcount.pl differentiate the two cases.
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
There has been some light flamewar on lkml about decoding oopses
in modules (as part of the crashdump flamewar).
Now this isn't rocket science, just the markup_oops.pl script
cheaped out and didn't handle modules. But really; a flamewar
all about that?? What happened to C++ in the kernel or reading
files from inside the kernel?
This patch adds module support to markup_oops.pl; it's not the
most pretty perl but it works for my testcases...
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It is useful for diagnosing boot performance to see where async function
calls are waiting on serialization... this patch adds this
functionality to the bootgraph.pl script.
The waiting time is shown as a half transparent, gray bar through the
block that is waiting.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I often change single options in .config files. Instead of using
an editor or one of the frontends it's convenient to do this from
the command line. It's also useful to do from automated build scripts
when building different variants from a base config file.
I extracted most of the CONFIG manipulation code from one of my
build scripts into a new shell script scripts/config
The script is not integrated with the normal Kconfig machinery
and doesn't do any checking against Kconfig files, but just manipulates
that text format. This is always done at make time anyways.
I believe this script would be a useful standard addition for scripts/*
Sample usage:
./scripts/config --disable smp
Disable SMP in .config file
./scripts/config --file otherdir/.config --module e1000e
Enable E1000E as module in otherdir/.config
./scripts/config --state smp
y
Check state of config option CONFIG_SMP
After merging into git please make scripts/config executable
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
This patch reintroduce the ALLSOURCE_ARCHS support for tags/TAGS/
cscope targets. The Kbuild previously has this feature, but after
moving the targets into scripts/tags.sh, ALLSOURCE_ARCHS disappears.
It's something like this:
$ make ALLSOURCE_ARCHS="x86 mips arm" tags cscope
Signed-off-by: Jike Song <albcamus@gmail.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Dave Jones, in his blog, had some feedback about the bootchart script:
Primarily his complaint was that shorter delays weren't visualized.
The reason for that was that too small delays will have their labels
mixed up in the graph in an unreadable mess.
This patch has a fix for this; for one, it makes the output wider,
so more will fit.
The second part is that smaller delays are now shown with a
much smaller font for the label; while this isn't per se
readable at a 1:1 zoom, at least you can zoom in with most SVG
viewing applications and see what it is you are looking at.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Rafael reported:
I get the following error from 'make modules_install' on my test boxes:
HOSTCC firmware/ihex2fw
/home/rafael/src/linux-2.6/firmware/ihex2fw.c:268: fatal error: opening dependency file firmware/.ihex2fw.d: Read-only file system
compilation terminated.
make[3]: *** [firmware/ihex2fw] Error 1
make[2]: *** [_modinst_post] Error 2
make[1]: *** [sub-make] Error 2
make: *** [all] Error 2
where the configuration is that the kernel is compiled on a build box
with 'make O=<destdir> -j5' and then <destdir> is mounted over NFS read-only by
each test box (full path to this directory is the same on the build box and on
the test boxes). Then, I cd into <destdir>, run 'make modules_install' and get
the error above.
The issue turns out to be that we when we install firmware pick
up the list of firmware blobs from firmware/Makefile.
And this triggers the Makefile rules to update ihex2fw.
There were two solutions for this issue:
1) Move the list of firmware blobs to a separate file
2) Avoid ihex2fw rebuild by moving it to scripts
As I seriously beleive that the list of firmware blobs should be
done in a fundamental different way solution 2) was selected.
Reported-and-tested-by: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: David Woodhouse <dwmw2@infradead.org>
