Re: [PATCH v3 3/9] efi/libstub: Remove .note.gnu.property
flat view
From: Will Deacon <will@kernel.org>
Date: 2020-06-24 15:26:56
Also in:
linux-arch, linux-efi, lkml
On Wed, Jun 24, 2020 at 02:48:55PM +0100, Dave Martin wrote:
On Wed, Jun 24, 2020 at 12:26:47PM +0100, Will Deacon wrote:quoted
On Wed, Jun 24, 2020 at 12:46:32PM +0200, Ard Biesheuvel wrote:quoted
On Wed, 24 Jun 2020 at 12:44, Will Deacon [off-list ref] wrote:quoted
For the kernel Image, how do we remove these sections? The objcopy flags in arch/arm64/boot/Makefile look both insufficient and out of date. My vmlinux ends up with both a ".notes" and a ".init.note.gnu.property" segment.The latter is the fault of the libstub make rules, that prepend .init to all section names.Hmm. I tried adding -mbranch-protection=none to arm64 cflags for the stub, but I still see this note in vmlinux. It looks like it comes in via the stub copy of lib-ctype.o, but I don't know why that would force the note. The cflags look ok to me [1] and I confirmed that the note is being generated by the compiler.quoted
I'm not sure if there is a point to having PAC and/or BTI in the EFI stub, given that it runs under the control of the firmware, with its memory mappings and PAC configuration etc.Agreed, I just can't figure out how to get rid of the note.Because this section is generated by the linker itself I think you might have to send it to /DISCARD/ in the link, or strip it explicitly after linking.
Right, but why is the linker generating that section in the first place? I'm compiling with -mbranch-protection=none and all the other objects linked into the stub do not have the section. I wonder if it's because lib/ctype.c doesn't have any executable code... Will _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel