KSYM_NAME_LEN is peculiar in that it does not include the space for the
trailing '\0', forcing all users to use KSYM_NAME_LEN + 1 when allocating
buffer.  This is nonsense and error-prone.  Moreover, when the caller
forgets that it's very likely to subtly bite back by corrupting the stack
because the last position of the buffer is always cleared to zero.

This patch increments KSYM_NAME_LEN by one and updates code accordingly.

* off-by-one bug in asm-powerpc/kprobes.h::kprobe_lookup_name() macro
  is fixed.

* Where MODULE_NAME_LEN and KSYM_NAME_LEN were used together,
  MODULE_NAME_LEN was treated as if it didn't include space for the
  trailing '\0'.  Fix it.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Acked-by: NPaulo Marques <pmarques@grupopie.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch fixes the following 2.6.22 regression with CONFIG_KALLSYMS=n:

<--  snip  -->

...
  CC      arch/m32r/kernel/traps.o
In file included from /home/bunk/linux/kernel-2.6/linux-2.6.22-rc6-mm1/arch/m32r/kernel/traps.c:14:
/home/bunk/linux/kernel-2.6/linux-2.6.22-rc6-mm1/include/linux/kallsyms.h: In function 'lookup_symbol_name':
/home/bunk/linux/kernel-2.6/linux-2.6.22-rc6-mm1/include/linux/kallsyms.h:66: error: 'ERANGE' undeclared (first use in this function)
/home/bunk/linux/kernel-2.6/linux-2.6.22-rc6-mm1/include/linux/kallsyms.h:66: error: (Each undeclared identifier is reported only once
/home/bunk/linux/kernel-2.6/linux-2.6.22-rc6-mm1/include/linux/kallsyms.h:66: error: for each function it appears in.)
/home/bunk/linux/kernel-2.6/linux-2.6.22-rc6-mm1/include/linux/kallsyms.h: In function 'lookup_symbol_attrs':
/home/bunk/linux/kernel-2.6/linux-2.6.22-rc6-mm1/include/linux/kallsyms.h:71: error: 'ERANGE' undeclared (first use in this function)
make[2]: *** [arch/m32r/kernel/traps.o] Error 1

<--  snip  -->
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Same story as with cat /proc/*/wchan race vs rmmod race, only
/proc/slab_allocators want more info than just symbol name.
Signed-off-by: NAlexey Dobriyan <adobriyan@sw.ru>
Acked-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

kallsyms_lookup() can go iterating over modules list unprotected which is OK
for emergency situations (oops), but not OK for regular stuff like
/proc/*/wchan.

Introduce lookup_symbol_name()/lookup_module_symbol_name() which copy symbol
name into caller-supplied buffer or return -ERANGE.  All copying is done with
module_mutex held, so...
Signed-off-by: NAlexey Dobriyan <adobriyan@sw.ru>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Today's print_symbol function dumps a kernel symbol with printk.  This
patch extends the functionality of kallsyms.c so that the symbol lookup
function may be used without the printk.  This is useful for modules that
want to dump symbols elsewhere, for example, to debugfs.  I intend to use
the new function call in the GFS2 file system (which will be a separate
patch).

[akpm@linux-foundation.org: build fix]
[clameter@sgi.com: sprint_symbol should return length of string like sprintf]
Signed-off-by: NRobert Peterson <rpeterso@redhat.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: "Randy.Dunlap" <rdunlap@xenotime.net>
Cc: Sam Ravnborg <sam@ravnborg.org>
Acked-by: NPaulo Marques <pmarques@grupopie.com>
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Some uses of kallsyms_lookup() do not need to find out the name of a symbol
and its module's name it belongs.  This is specially true in arch specific
code, which needs to unwind the stack to show the back trace during oops
(mips is an example).  In this specific case, we just need to retreive the
function's size and the offset of the active intruction inside it.

Adds a new entry "kallsyms_lookup_size_offset()" This new entry does
exactly the same as kallsyms_lookup() but does not require any buffers to
store any names.

It returns 0 if it fails otherwise 1.
Signed-off-by: NFranck Bui-Huu <vagabon.xyz@gmail.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Provide a common print_ip_sym() function that prints the passed instruction
pointer as well as the symbol belonging to it.  Avoids adding a bunch of
#ifdef CONFIG_64BIT in order to get the printk format right on 32/64 bit
platforms.
Acked-by: NIngo Molnar <mingo@elte.hu>
Cc: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Have a special version of print_symbol() for s390 which clears the most
significant bit of addr before calling __print_symbol().  This seems to be
better than checking/changing each place in the kernel that saves an
instruction pointer.

Without this the output would look like:

hardirqs last  enabled at (30907): [<80018c6a>] 0x80018c6a
hardirqs last disabled at (30908): [<8001e48c>] 0x8001e48c
softirqs last  enabled at (30904): [<8001dc96>] 0x8001dc96
softirqs last disabled at (30897): [<8001dc50>] 0x8001dc50

instead of this:

hardirqs last  enabled at (19421): [<80018c72>] cpu_idle+0x176/0x1c4
hardirqs last disabled at (19422): [<8001e494>] io_no_vtime+0xa/0x1a
softirqs last  enabled at (19418): [<8001dc9e>] do_softirq+0xa6/0xe8
softirqs last disabled at (19411): [<8001dc58>] do_softirq+0x60/0xe8
Acked-by: NIngo Molnar <mingo@elte.hu>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NDavid Woodhouse <dwmw2@infradead.org>

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!