linux/arch/arm64/kernel/vdso
Will Deacon 9a96428557 arm64: vdso: Don't prefix sigreturn trampoline with a BTI C instruction
For better or worse, GDB relies on the exact instruction sequence in the
VDSO sigreturn trampoline in order to unwind from signals correctly.
Commit c91db232da ("arm64: vdso: Convert to modern assembler annotations")
unfortunately added a BTI C instruction to the start of __kernel_rt_sigreturn,
which breaks this check. Thankfully, it's also not required, since the
trampoline is called from a RET instruction when returning from the signal
handler

Remove the unnecessary BTI C instruction from __kernel_rt_sigreturn,
and do the same for the 32-bit VDSO as well for good measure.

Cc: Daniel Kiss <daniel.kiss@arm.com>
Cc: Tamas Zsoldos <tamas.zsoldos@arm.com>
Reviewed-by: Dave Martin <dave.martin@arm.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Fixes: c91db232da ("arm64: vdso: Convert to modern assembler annotations")
Signed-off-by: Will Deacon <will@kernel.org>
2020-05-21 12:57:18 +01:00
..
.gitignore .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
gen_vdso_offsets.sh License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
Makefile arm64: vdso: Force the vDSO to be linked as BTI when built for BTI 2020-05-07 17:53:20 +01:00
note.S arm64: vdso: Annotate for BTI 2020-05-07 17:53:20 +01:00
sigreturn.S arm64: vdso: Don't prefix sigreturn trampoline with a BTI C instruction 2020-05-21 12:57:18 +01:00
vdso.lds.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234 2019-06-19 17:09:07 +02:00
vdso.S arm64: vdso: Annotate for BTI 2020-05-07 17:53:20 +01:00
vgettimeofday.c arm64: vdso: Include common headers in the vdso library 2020-03-21 15:24:01 +01:00