| Message ID | 20210107123331.354075-1-alobakin@pm.me (mailing list archive) |
|---|---|
| Headers | show |
| Series | MIPS: vmlinux.lds.S sections fixes & cleanup | expand |
On Thu, Jan 07, 2021 at 12:33:38PM +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); > - 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 10.2.0; > - LLVM stack 11.0.0. Nice! Thanks for hunting down the corner cases. :)
On Thu, Jan 07, 2021 at 12:33:38PM +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); > - 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 10.2.0; > - LLVM stack 11.0.0. > > 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 > > Alexander Lobakin (7): > MIPS: vmlinux.lds.S: add missing PAGE_ALIGNED_DATA() section > MIPS: vmlinux.lds.S: add ".gnu.attributes" to DISCARDS > MIPS: properly stop .eh_frame generation > MIPS: vmlinux.lds.S: catch bad .rel.dyn at link time > MIPS: vmlinux.lds.S: explicitly declare .got table > vmlinux.lds.h: catch compound literals into data and BSS > MIPS: select ARCH_WANT_LD_ORPHAN_WARN this breaks my builds: LD vmlinux.o MODPOST vmlinux.symvers MODINFO modules.builtin.modinfo GEN modules.builtin LD .tmp_vmlinux.kallsyms1 mips64-linux-gnu-ld: Unexpected run-time relocations (.rel) detected! $ mips64-linux-gnu-ld --version GNU ld version 2.27-3.fc24 $ mips64-linux-gnu-gcc --version mips64-linux-gnu-gcc (GCC) 6.1.1 20160621 (Red Hat Cross 6.1.1-2) Thomas.
From: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Date: Sat, 9 Jan 2021 12:12:59 +0100 > On Thu, Jan 07, 2021 at 12:33:38PM +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); >> - 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 10.2.0; >> - LLVM stack 11.0.0. >> >> 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 >> >> Alexander Lobakin (7): >> MIPS: vmlinux.lds.S: add missing PAGE_ALIGNED_DATA() section >> MIPS: vmlinux.lds.S: add ".gnu.attributes" to DISCARDS >> MIPS: properly stop .eh_frame generation >> MIPS: vmlinux.lds.S: catch bad .rel.dyn at link time >> MIPS: vmlinux.lds.S: explicitly declare .got table >> vmlinux.lds.h: catch compound literals into data and BSS >> MIPS: select ARCH_WANT_LD_ORPHAN_WARN > > this breaks my builds: > > LD vmlinux.o > MODPOST vmlinux.symvers > MODINFO modules.builtin.modinfo > GEN modules.builtin > LD .tmp_vmlinux.kallsyms1 > mips64-linux-gnu-ld: Unexpected run-time relocations (.rel) detected! I think they should be handled as it's done for ARM64 [0]. Will do v5 soon. [0] https://elixir.bootlin.com/linux/v5.11-rc2/source/arch/arm64/kernel/vmlinux.lds.S#L219 > $ mips64-linux-gnu-ld --version > GNU ld version 2.27-3.fc24 > > $ mips64-linux-gnu-gcc --version > mips64-linux-gnu-gcc (GCC) 6.1.1 20160621 (Red Hat Cross 6.1.1-2) > > Thomas. Thanks, Alex > -- > Crap can work. Given enough thrust pigs will fly, but it's not necessarily a > good idea. [ RFC1925, 2.3 ]