Commit graph

4 commits

Author SHA1 Message Date
Andrey Ryabinin
9ddf82521c kernel: add support for .init_array.* constructors
KASan uses constructors for initializing redzones for global variables.
Globals instrumentation in GCC 4.9.2 produces constructors with priority
(.init_array.00099)

Currently kernel ignores such constructors.  Only constructors with
default priority supported (.init_array)

This patch adds support for constructors with priorities.  For kernel
image we put pointers to constructors between __ctors_start/__ctors_end
and do_ctors() will call them on start up.  For modules we merge
.init_array.* sections into resulting .init_array.  Module code properly
handles constructors in .init_array section.

Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Signed-off-by: Andrey Konovalov <adech.fo@gmail.com>
Cc: Yuri Gribov <tetra2005@gmail.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-13 21:21:42 -08:00
Rabin Vincent
5d8591bc0f module: set ksymtab/kcrctab* section addresses to 0x0
These __ksymtab*/__kcrctab* sections currently have non-zero addresses.
Non-zero section addresses in a relocatable ELF confuse GDB and it ends
up not relocating all symbols when add-symbol-file is used on modules
which have exports.  The kernel's module loader does not care about
these addresses, so let's just set them to zero.

 Before:

  $ readelf -S lib/notifier-error-inject.ko   | grep 'Name\| __ksymtab_gpl'
    [Nr] Name              Type            Addr     Off    Size   ES Flg Lk Inf Al
    [ 8] __ksymtab_gpl     PROGBITS        0000000c 0001b4 000010 00   A  0   0  4

  (gdb) add-symbol-file lib/notifier-error-inject.ko 0x500000 -s .bss 0x700000
  add symbol table from file "lib/notifier-error-inject.ko" at
     .text_addr = 0x500000
     .bss_addr = 0x700000
  (gdb) p &notifier_err_inject_dir
  $3 = (struct dentry **) 0x0

 After:

  $ readelf -S lib/notifier-error-inject.ko   | grep 'Name\| __ksymtab_gpl'
    [Nr] Name              Type            Addr     Off    Size   ES Flg Lk Inf Al
    [ 8] __ksymtab_gpl     PROGBITS        00000000 0001b4 000010 00   A  0   0  4

  (gdb) add-symbol-file lib/notifier-error-inject.ko 0x500000 -s .bss 0x700000
  add symbol table from file "lib/notifier-error-inject.ko" at
     .text_addr = 0x500000
     .bss_addr = 0x700000
  (gdb) p &notifier_err_inject_dir
  $3 = (struct dentry **) 0x700000

Signed-off-by: Rabin Vincent <rabin.vincent@axis.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-02-06 15:31:40 +10:30
Alessio Igor Bogani
f02e8a6596 module: Sort exported symbols
This patch places every exported symbol in its own section
(i.e. "___ksymtab+printk").  Thus the linker will use its SORT() directive
to sort and finally merge all symbol in the right and final section
(i.e. "__ksymtab").

The symbol prefixed archs use an underscore as prefix for symbols.
To avoid collision we use a different character to create the temporary
section names.

This work was supported by a hardware donation from the CE Linux Forum.

Signed-off-by: Alessio Igor Bogani <abogani@kernel.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (folded in '+' fixup)
Tested-by: Dirk Behme <dirk.behme@googlemail.com>
2011-05-19 16:55:27 +09:30
Tejun Heo
405d967dc7 linker script: throw away .discard section
x86 throws away .discard section but no other archs do.  Also,
.discard is not thrown away while linking modules.  Make every arch
and module linking throw it away.  This will be used to define dummy
variables for percpu declarations and definitions.

This patch is based on Ivan Kokshaysky's alpha percpu patch.

[ Impact: always throw away everything in .discard ]

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Bryan Wu <cooloney@kernel.org>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Ingo Molnar <mingo@elte.hu>
2009-06-24 15:13:38 +09:00