Alex Smith e16046836e recordmcount/MIPS: Fix possible incorrect mcount_loc table entries in modules ... commit 91ad11d7cc upstream. On MIPS calls to _mcount in modules generate 2 instructions to load the _mcount address (and therefore 2 relocations). The mcount_loc table should only reference the first of these, so the second is filtered out by checking the relocation offset and ignoring ones that immediately follow the previous one seen. However if a module has an _mcount call at offset 0, the second relocation would not be filtered out due to old_r_offset == 0 being taken to mean that the current relocation is the first one seen, and both would end up in the mcount_loc table. This results in ftrace_make_nop() patching both (adjacent) instructions to branches over the _mcount call sequence like so: 0xffffffffc08a8000: 04 00 00 10 b 0xffffffffc08a8014 0xffffffffc08a8004: 04 00 00 10 b 0xffffffffc08a8018 0xffffffffc08a8008: 2d 08 e0 03 move at,ra ... The second branch is in the delay slot of the first, which is defined to be unpredictable - on the platform on which this bug was encountered, it triggers a reserved instruction exception. Fix by initializing old_r_offset to ~0 and using that instead of 0 to determine whether the current relocation is the first seen. Signed-off-by: Alex Smith <alex.smith@imgtec.com> Cc: linux-kernel@vger.kernel.org Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/7098/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2014-07-06 18:54:13 -07:00
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basic
coccinelle
dtc	dtc: ensure #line directives don't consume data from the next line	2013-06-13 22:12:15 +01:00
genksyms
kconfig	kconfig/menu.c: fix multiple references to expressions in menu_add_prop()	2013-05-30 00:14:01 +02:00
ksymoops
mod	powerpc: Add vr save/restore functions	2014-05-30 21:52:12 -07:00
package	deb-pkg: Fix cross-building linux-headers package	2014-03-31 09:58:13 -07:00
rt-tester
selinux
tracing
.gitignore
asn1_compiler.c
bin2c.c
bloat-o-meter
bootgraph.pl
checkincludes.pl
checkkconfigsymbols.sh
checkpatch.pl
checkstack.pl
checksyscalls.sh
checkversion.pl
cleanfile
cleanpatch
coccicheck
config	scripts/config: fix assignment of parameters for short version of --*-after options	2013-05-20 14:15:17 +02:00
conmakehash.c
decodecode
depmod.sh
diffconfig
docproc.c
export_report.pl
extract-ikconfig
extract-vmlinux
gcc-goto.sh
gcc-version.sh
gcc-x86_32-has-stack-protector.sh
gcc-x86_64-has-stack-protector.sh
gen_initramfs_list.sh
get_maintainer.pl
gfp-translate
headerdep.pl
headers_check.pl
headers_install.sh	kbuild: fix make headers_install when path is too long	2014-04-14 06:42:14 -07:00
headers.sh
kallsyms.c	scripts/kallsyms: filter symbols not in kernel address space	2013-11-13 12:05:32 +09:00
Kbuild.include
kernel-doc
Lindent
link-vmlinux.sh	scripts/kallsyms: filter symbols not in kernel address space	2013-11-13 12:05:32 +09:00
Makefile
Makefile.asm-generic
Makefile.build
Makefile.clean
Makefile.fwinst
Makefile.headersinst	kbuild: fix make headers_install when path is too long	2014-04-14 06:42:14 -07:00
Makefile.help
Makefile.host
Makefile.lib	kbuild: make sure we clean up DTB temporary files	2013-06-13 22:12:13 +01:00
Makefile.modbuiltin
Makefile.modinst
Makefile.modpost
Makefile.modsign
makelst
markup_oops.pl
mkcompile_h
mkmakefile
mksysmap
mkuboot.sh
mkversion
module-common.lds
namespace.pl
patch-kernel
pnmtologo.c
profile2linkerlist.pl
recordmcount.c
recordmcount.h	recordmcount/MIPS: Fix possible incorrect mcount_loc table entries in modules	2014-07-06 18:54:13 -07:00
recordmcount.pl
setlocalversion
show_delta
sign-file
sortextable.c
sortextable.h
tags.sh
unifdef.c
ver_linux
xz_wrap.sh