On Sun, Jan 10, 2021 at 11:53:50AM +0000, Alexander Lobakin wrote: > 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).
Looks good; which tree will this land through? -Kees > > 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-aloba...@pm.me > [1] https://lore.kernel.org/linux-mips/20210106200713.31840-1-aloba...@pm.me > [2] https://lore.kernel.org/linux-mips/20210107115120.281008-1-aloba...@pm.me > [3] https://lore.kernel.org/linux-mips/20210107123331.354075-1-aloba...@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 > > -- Kees Cook