linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
* [PATCH v5 mips-next 0/9] MIPS: vmlinux.lds.S sections fixes & cleanup
@ 2021-01-10 11:53 Alexander Lobakin
  2021-01-10 11:56 ` [PATCH v5 mips-next 1/9] MIPS: vmlinux.lds.S: add missing PAGE_ALIGNED_DATA() section Alexander Lobakin
                   ` (2 more replies)
  0 siblings, 3 replies; 17+ messages in thread
From: Alexander Lobakin @ 2021-01-10 11:53 UTC (permalink / raw)
  To: Thomas Bogendoerfer
  Cc: Arnd Bergmann, Nathan Chancellor, Nick Desaulniers, Huacai Chen,
	Pei Huang, Kees Cook, Alexander Lobakin, Fangrui Song,
	Jiaxun Yang, Ralf Baechle, Corey Minyard, linux-mips,
	linux-kernel, linux-arch, stable, clang-built-linux

This series hunts the problems discovered after manual enabling of
ARCH_WANT_LD_ORPHAN_WARN. Notably:
 - adds the missing PAGE_ALIGNED_DATA() section affecting VDSO
   placement (marked for stable);
 - stops blind catching of orphan text sections with .text.*
   directive;
 - properly stops .eh_frame section generation.

Compile and runtime tested on MIPS32R2 CPS board with no issues
using two different toolkits:
 - Binutils 2.35.1, GCC 10.2.1 (with Alpine patches);
 - LLVM stack: 11.0.0 and from latest Git snapshot.

Since v4 [3]:
 - new: drop redundant .text.cps-vec creation and blind inclusion
   of orphan text sections via .text.* directive in vmlinux.lds.S;
 - don't assert SIZEOF(.rel.dyn) as it's reported that it may be not
   empty on certain machines and compilers (Thomas);
 - align GOT table like it's done for ARM64;
 - new: catch UBSAN's "unnamed data" sections in generic definitions
   when building with LD_DEAD_CODE_DATA_ELIMINATION;
 - collect Reviewed-bys (Kees, Nathan).

Since v3 [2]:
 - fix the third patch as GNU stack emits .rel.dyn into VDSO for
   some reason if .cfi_sections is specified.

Since v2 [1]:
 - stop discarding .eh_frame and just prevent it from generating
   (Kees);
 - drop redundant sections assertions (Fangrui);
 - place GOT table in .text instead of asserting as it's not empty
   when building with LLVM (Nathan);
 - catch compound literals in generic definitions when building with
   LD_DEAD_CODE_DATA_ELIMINATION (Kees);
 - collect two Reviewed-bys (Kees).

Since v1 [0]:
 - catch .got entries too as LLD may produce it (Nathan);
 - check for unwanted sections to be zero-sized instead of
   discarding (Fangrui).

[0] https://lore.kernel.org/linux-mips/20210104121729.46981-1-alobakin@pm.me
[1] https://lore.kernel.org/linux-mips/20210106200713.31840-1-alobakin@pm.me
[2] https://lore.kernel.org/linux-mips/20210107115120.281008-1-alobakin@pm.me
[3] https://lore.kernel.org/linux-mips/20210107123331.354075-1-alobakin@pm.me

Alexander Lobakin (9):
  MIPS: vmlinux.lds.S: add missing PAGE_ALIGNED_DATA() section
  MIPS: CPS: don't create redundant .text.cps-vec section
  MIPS: vmlinux.lds.S: add ".gnu.attributes" to DISCARDS
  MIPS: properly stop .eh_frame generation
  MIPS: vmlinux.lds.S: explicitly catch .rel.dyn symbols
  MIPS: vmlinux.lds.S: explicitly declare .got table
  vmlinux.lds.h: catch compound literals into data and BSS
  vmlinux.lds.h: catch UBSAN's "unnamed data" into data
  MIPS: select ARCH_WANT_LD_ORPHAN_WARN

 arch/mips/Kconfig                 |  1 +
 arch/mips/include/asm/asm.h       | 18 ++++++++++++++++++
 arch/mips/kernel/cps-vec.S        |  1 -
 arch/mips/kernel/vmlinux.lds.S    | 11 +++++++++--
 include/asm-generic/vmlinux.lds.h |  6 +++---
 5 files changed, 31 insertions(+), 6 deletions(-)

-- 
2.30.0



^ permalink raw reply	[flat|nested] 17+ messages in thread
end of thread, other threads:[~2021-01-15 14:48 UTC | newest]

Thread overview: 17+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-01-10 11:53 [PATCH v5 mips-next 0/9] MIPS: vmlinux.lds.S sections fixes & cleanup Alexander Lobakin
2021-01-10 11:56 ` [PATCH v5 mips-next 1/9] MIPS: vmlinux.lds.S: add missing PAGE_ALIGNED_DATA() section Alexander Lobakin
2021-01-10 11:56   ` [PATCH v5 mips-next 2/9] MIPS: CPS: don't create redundant .text.cps-vec section Alexander Lobakin
2021-01-10 11:56   ` [PATCH v5 mips-next 3/9] MIPS: vmlinux.lds.S: add ".gnu.attributes" to DISCARDS Alexander Lobakin
2021-01-10 11:56   ` [PATCH v5 mips-next 4/9] MIPS: properly stop .eh_frame generation Alexander Lobakin
2021-01-10 11:56   ` [PATCH v5 mips-next 5/9] MIPS: vmlinux.lds.S: explicitly catch .rel.dyn symbols Alexander Lobakin
2021-01-11  1:28     ` Nathan Chancellor
2021-01-10 11:56   ` [PATCH v5 mips-next 6/9] MIPS: vmlinux.lds.S: explicitly declare .got table Alexander Lobakin
2021-01-10 11:56   ` [PATCH v5 mips-next 7/9] vmlinux.lds.h: catch compound literals into data and BSS Alexander Lobakin
2021-01-10 11:56   ` [PATCH v5 mips-next 8/9] vmlinux.lds.h: catch UBSAN's "unnamed data" into data Alexander Lobakin
2021-01-11  2:05     ` Nathan Chancellor
2021-01-10 11:57   ` [PATCH v5 mips-next 9/9] MIPS: select ARCH_WANT_LD_ORPHAN_WARN Alexander Lobakin
2021-01-11 19:53 ` [PATCH v5 mips-next 0/9] MIPS: vmlinux.lds.S sections fixes & cleanup Kees Cook
2021-01-11 20:57   ` Alexander Lobakin
2021-01-11 22:43     ` Thomas Bogendoerfer
2021-01-15 11:15       ` Arnd Bergmann
2021-01-15 14:40 ` Thomas Bogendoerfer

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).