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arm64: Unconditionally select CONFIG_JUMP_LABEL 

Aneesh reports that his kernel fails to boot in nVHE mode with
KVM's protected mode enabled. Further investigation by Mostafa
reveals that this fails because CONFIG_JUMP_LABEL=n and that
we have static keys shared between EL1 and EL2.

While this can be worked around, it is obvious that we have long
relied on having CONFIG_JUMP_LABEL enabled at all times, as all
supported compilers now have 'asm goto' (which is the basic block
for jump labels).

Let's simplify our lives once and for all by mandating jump labels.
It's not like anyone else is testing anything without them, and
we already rely on them for other things (kfence, xfs, preempt).

Link: https://lore.kernel.org/r/yq5ah60pkq03.fsf@kernel.org
Reported-by: Aneesh Kumar K.V <aneesh.kumar@kernel.org>
Reported-by: Mostafa Saleh <smostafa@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Cc: Will Deacon <will@kernel.org>
Cc: Catalin marinas <catalin.marinas@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20250613141936.2219895-1-maz@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
This commit is contained in:
Marc Zyngier 2025-06-13 15:19:36 +01:00 committed by Will Deacon
parent ef8923e6c0
commit 727c2a53cf
2 changed files with 2 additions and 2 deletions
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1
arch/arm64/Kconfig
View File

@ -256,6 +256,7 @@ config ARM64
select HOTPLUG_SMT if HOTPLUG_CPU
select IRQ_DOMAIN
select IRQ_FORCED_THREADING
select JUMP_LABEL
select KASAN_VMALLOC if KASAN
select LOCK_MM_AND_FIND_VMA
select MODULES_USE_ELF_RELA

3
arch/arm64/kernel/Makefile
View File

@ -34,7 +34,7 @@ obj-y := debug-monitors.o entry.o irq.o fpsimd.o \
cpufeature.o alternative.o cacheinfo.o \
smp.o smp_spin_table.o topology.o smccc-call.o \
syscall.o proton-pack.o idle.o patching.o pi/ \
rsi.o
rsi.o jump_label.o
obj-$(CONFIG_COMPAT) += sys32.o signal32.o \
sys_compat.o
@ -47,7 +47,6 @@ obj-$(CONFIG_PERF_EVENTS) += perf_regs.o perf_callchain.o
obj-$(CONFIG_HARDLOCKUP_DETECTOR_PERF) += watchdog_hld.o
obj-$(CONFIG_HAVE_HW_BREAKPOINT) += hw_breakpoint.o
obj-$(CONFIG_CPU_PM) += sleep.o suspend.o
obj-$(CONFIG_JUMP_LABEL) += jump_label.o
obj-$(CONFIG_KGDB) += kgdb.o
obj-$(CONFIG_EFI) += efi.o efi-rt-wrapper.o
obj-$(CONFIG_PCI) += pci.o