The only architecture that actually needs to convert compiler generated jump label NOP encodings into something else at runtime is MIPS, because the assembler cannot be trusted to emit a sequence that can be safely patched into a branch instruction. All other architectures either do nothing with jump label NOPs at load time, or patch a perfectly good NOP into a different one, or into the same one - none of this seems very useful, so let's get rid of it where we can. Changes since v1: - use a default implementation of arch_jump_label_transform_static() instead of an empty macro in patch #3 - fix MIPS with CONFIG_MODULES=n - add acks from Mark and Peter to patch #3 Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Mark Rutland <mark.rutland@xxxxxxx> Cc: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx> Cc: Heiko Carstens <hca@xxxxxxxxxxxxx> Cc: Vasily Gorbik <gor@xxxxxxxxxxxxx> Cc: Alexander Gordeev <agordeev@xxxxxxxxxxxxx> Cc: Christian Borntraeger <borntraeger@xxxxxxxxxxxxx> Cc: Sven Schnelle <svens@xxxxxxxxxxxxx> Cc: linux-mips@xxxxxxxxxxxxxxx Cc: linux-s390@xxxxxxxxxxxxxxx Ard Biesheuvel (3): jump_label: s390: avoid pointless initial NOP patching jump_label: mips: move module NOP patching into arch code jump_label: make initial NOP patching the special case Documentation/staging/static-keys.rst | 3 -- arch/arc/kernel/jump_label.c | 13 ------- arch/arm/kernel/jump_label.c | 6 --- arch/arm64/kernel/jump_label.c | 11 ------ arch/mips/include/asm/jump_label.h | 2 + arch/mips/kernel/jump_label.c | 19 +++++++++ arch/mips/kernel/module.c | 5 ++- arch/parisc/kernel/jump_label.c | 11 ------ arch/riscv/kernel/jump_label.c | 12 ------ arch/s390/include/asm/jump_label.h | 5 +-- arch/s390/kernel/jump_label.c | 28 +++---------- arch/s390/kernel/module.c | 1 - arch/sparc/kernel/module.c | 3 -- arch/x86/kernel/jump_label.c | 13 ------- arch/x86/kernel/module.c | 3 -- include/linux/jump_label.h | 7 +--- kernel/jump_label.c | 41 +++----------------- 17 files changed, 38 insertions(+), 145 deletions(-) -- 2.35.1
