linux-stable.git/arch/mips/kernel/vmlinux.lds.S, branch v5.10.78

MIPS: properly stop .eh_frame generation

2021-03-04T10:37:41+00:00

[ Upstream commit 894ef530012fb5078466efdfb2c15d8b2f1565cd ]

Commit 866b6a89c6d1 ("MIPS: Add DWARF unwinding to assembly") added
-fno-asynchronous-unwind-tables to KBUILD_CFLAGS to prevent compiler
from emitting .eh_frame symbols.
However, as MIPS heavily uses CFI, that's not enough. Use the
approach taken for x86 (as it also uses CFI) and explicitly put CFI
symbols into the .debug_frame section (except for VDSO).
This allows us to drop .eh_frame from DISCARDS as it's no longer
being generated.

Fixes: 866b6a89c6d1 ("MIPS: Add DWARF unwinding to assembly")
Suggested-by: Kees Cook 
Signed-off-by: Alexander Lobakin 
Reviewed-by: Kees Cook 
Reviewed-by: Nathan Chancellor 
Signed-off-by: Thomas Bogendoerfer 
Signed-off-by: Sasha Levin

MIPS: vmlinux.lds.S: add missing PAGE_ALIGNED_DATA() section

2021-03-04T10:37:19+00:00

commit 8ac7c87acdcac156670f9920c8acbd84308ff4b1 upstream.

MIPS uses its own declaration of rwdata, and thus it should be kept
in sync with the asm-generic one. Currently PAGE_ALIGNED_DATA() is
missing from the linker script, which emits the following ld
warnings:

mips-alpine-linux-musl-ld: warning: orphan section
`.data..page_aligned' from `arch/mips/kernel/vdso.o' being placed
in section `.data..page_aligned'
mips-alpine-linux-musl-ld: warning: orphan section
`.data..page_aligned' from `arch/mips/vdso/vdso-image.o' being placed
in section `.data..page_aligned'

Add the necessary declaration, so the mentioned structures will be
placed in vmlinux as intended:

ffffffff80630580 D __end_once
ffffffff80630580 D __start___dyndbg
ffffffff80630580 D __start_once
ffffffff80630580 D __stop___dyndbg
ffffffff80634000 d mips_vdso_data
ffffffff80638000 d vdso_data
ffffffff80638580 D _gp
ffffffff8063c000 T __init_begin
ffffffff8063c000 D _edata
ffffffff8063c000 T _sinittext

->

ffffffff805a4000 D __end_init_task
ffffffff805a4000 D __nosave_begin
ffffffff805a4000 D __nosave_end
ffffffff805a4000 d mips_vdso_data
ffffffff805a8000 d vdso_data
ffffffff805ac000 D mmlist_lock
ffffffff805ac080 D tasklist_lock

Fixes: ebb5e78cc634 ("MIPS: Initial implementation of a VDSO")
Signed-off-by: Alexander Lobakin 
Reviewed-by: Kees Cook 
Reviewed-by: Nathan Chancellor 
Cc: stable@vger.kernel.org # 4.4+
Signed-off-by: Thomas Bogendoerfer 
Signed-off-by: Greg Kroah-Hartman

vmlinux.lds.h: Split ELF_DETAILS from STABS_DEBUG

2020-09-01T07:50:35+00:00

The .comment section doesn't belong in STABS_DEBUG. Split it out into a
new macro named ELF_DETAILS. This will gain other non-debug sections
that need to be accounted for when linking with --orphan-handling=warn.

Signed-off-by: Kees Cook 
Signed-off-by: Ingo Molnar 
Cc: linux-arch@vger.kernel.org
Link: https://lore.kernel.org/r/20200821194310.3089815-5-keescook@chromium.org

MIPS: Truncate link address into 32bit for 32bit kernel

2020-05-07T08:31:01+00:00

LLD failed to link vmlinux with 64bit load address for 32bit ELF
while bfd will strip 64bit address into 32bit silently.
To fix LLD build, we should truncate load address provided by platform
into 32bit for 32bit kernel.

Signed-off-by: Jiaxun Yang 
Link: https://github.com/ClangBuiltLinux/linux/issues/786
Link: https://sourceware.org/bugzilla/show_bug.cgi?id=25784
Reviewed-by: Fangrui Song 
Reviewed-by: Kees Cook 
Tested-by: Nathan Chancellor 
Cc: Maciej W. Rozycki 
Tested-by: Nick Desaulniers 
Signed-off-by: Thomas Bogendoerfer

vmlinux.lds.h: Replace RODATA with RO_DATA

2019-11-04T14:53:15+00:00

There's no reason to keep the RODATA macro: replace the callers with
the expected RO_DATA macro.

Signed-off-by: Kees Cook 
Signed-off-by: Borislav Petkov 
Cc: Andy Lutomirski 
Cc: Arnd Bergmann 
Cc: Dave Hansen 
Cc: linux-alpha@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-c6x-dev@linux-c6x.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Michael Ellerman 
Cc: Michal Simek 
Cc: Rick Edgecombe 
Cc: Segher Boessenkool 
Cc: Will Deacon 
Cc: x86-ml 
Cc: Yoshinori Sato 
Link: https://lkml.kernel.org/r/20191029211351.13243-12-keescook@chromium.org

vmlinux.lds.h: Move NOTES into RO_DATA

2019-11-04T14:34:41+00:00

The .notes section should be non-executable read-only data. As such,
move it to the RO_DATA macro instead of being per-architecture defined.

Signed-off-by: Kees Cook 
Signed-off-by: Borislav Petkov 
Acked-by: Heiko Carstens  # s390
Cc: Andy Lutomirski 
Cc: Arnd Bergmann 
Cc: Dave Hansen 
Cc: linux-alpha@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-c6x-dev@linux-c6x.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Michael Ellerman 
Cc: Michal Simek 
Cc: Rick Edgecombe 
Cc: Segher Boessenkool 
Cc: Will Deacon 
Cc: x86-ml 
Cc: Yoshinori Sato 
Link: https://lkml.kernel.org/r/20191029211351.13243-11-keescook@chromium.org

vmlinux.lds.h: Move Program Header restoration into NOTES macro

2019-11-04T14:34:39+00:00

In preparation for moving NOTES into RO_DATA, make the Program Header
assignment restoration be part of the NOTES macro itself.

Signed-off-by: Kees Cook 
Signed-off-by: Borislav Petkov 
Acked-by: Heiko Carstens  # s390
Cc: Andy Lutomirski 
Cc: Arnd Bergmann 
Cc: Dave Hansen 
Cc: linux-alpha@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-c6x-dev@linux-c6x.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Michael Ellerman 
Cc: Michal Simek 
Cc: Rick Edgecombe 
Cc: Segher Boessenkool 
Cc: Will Deacon 
Cc: x86-ml 
Cc: Yoshinori Sato 
Link: https://lkml.kernel.org/r/20191029211351.13243-10-keescook@chromium.org

vmlinux.lds.h: Provide EMIT_PT_NOTE to indicate export of .notes

2019-11-04T14:34:38+00:00

In preparation for moving NOTES into RO_DATA, provide a mechanism for
architectures that want to emit a PT_NOTE Program Header to do so.

Signed-off-by: Kees Cook 
Signed-off-by: Borislav Petkov 
Acked-by: Heiko Carstens  # s390
Cc: Andy Lutomirski 
Cc: Arnd Bergmann 
Cc: Dave Hansen 
Cc: linux-alpha@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-c6x-dev@linux-c6x.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Michael Ellerman 
Cc: Michal Simek 
Cc: Rick Edgecombe 
Cc: Segher Boessenkool 
Cc: Will Deacon 
Cc: x86-ml 
Cc: Yoshinori Sato 
Link: https://lkml.kernel.org/r/20191029211351.13243-9-keescook@chromium.org

MIPS: Ensure ELF appended dtb is relocated

2019-03-11T18:08:31+00:00

This fixes booting with the combination of CONFIG_RELOCATABLE=y
and CONFIG_MIPS_ELF_APPENDED_DTB=y.

Sections that appear after the relocation table are not relocated
on system boot (except .bss, which has special handling).

With CONFIG_MIPS_ELF_APPENDED_DTB, the dtb is part of the
vmlinux ELF, so it must be relocated together with everything else.

Fixes: 069fd766271d ("MIPS: Reserve space for relocation table")
Signed-off-by: Yasha Cherikovsky 
Signed-off-by: Paul Burton 
Cc: Ralf Baechle 
Cc: Paul Burton 
Cc: James Hogan 
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Cc: stable@vger.kernel.org # v4.7+

MIPS: Enable dead code elimination

2018-11-21T23:36:49+00:00

Select CONFIG_HAVE_LD_DEAD_CODE_DATA_ELIMINATION for MIPS, allowing the
user to enable dead code elimination. In order for this to work, ensure
that we keep the data bus exception table & the machine list by
annotating them with KEEP.

This shrinks both 32r2el_defconfig & 64r6el_defconfig builds by ~6%, as
shown by numbers from scripts/bloat-o-meter:

          | 32r2el_defconfig | 64r6el_defconfig
  --------|------------------|------------------
   No DCE | 8919864          | 8286307
      DCE | 8338988 (-6.51%) | 7741808 (-6.57%)

Signed-off-by: Paul Burton 
Patchwork: https://patchwork.linux-mips.org/patch/21187/
Cc: linux-mips@linux-mips.org