From: Kees Cook <keescook@xxxxxxxxxxxx>
Subject: arm64: move jump_label_init() before parse_early_param()
While jump_label_init() was moved earlier in the boot process in
efd9e03facd0 ("arm64: Use static keys for CPU features"), it wasn't early
enough for early params to use it. The old state of things was as
described here...
init/main.c calls out to arch-specific things before general jump label
and early param handling:
asmlinkage __visible void __init start_kernel(void)
{
...
setup_arch(&command_line);
...
smp_prepare_boot_cpu();
...
/* parameters may set static keys */
jump_label_init();
parse_early_param();
...
}
x86 setup_arch() wants those earlier, so it handles jump label and
early param:
void __init setup_arch(char **cmdline_p)
{
...
jump_label_init();
...
parse_early_param();
...
}
arm64 setup_arch() only had early param:
void __init setup_arch(char **cmdline_p)
{
...
parse_early_param();
...
}
with jump label later in smp_prepare_boot_cpu():
void __init smp_prepare_boot_cpu(void)
{
...
jump_label_init();
...
}
This moves arm64 jump_label_init() from smp_prepare_boot_cpu() to
setup_arch(), as done already on x86, in preparation from early param
usage in the init_on_alloc/free() series:
https://lkml.kernel.org/r/1561572949.5154.81.camel@xxxxxx
Link: http://lkml.kernel.org/r/201906271003.005303B52@keescook
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
Acked-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>
Acked-by: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: Alexander Potapenko <glider@xxxxxxxxxx>
Cc: Qian Cai <cai@xxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
arch/arm64/kernel/setup.c | 5 +++++
arch/arm64/kernel/smp.c | 5 -----
2 files changed, 5 insertions(+), 5 deletions(-)
--- a/arch/arm64/kernel/setup.c~arm64-move-jump_label_init-before-parse_early_param
+++ a/arch/arm64/kernel/setup.c
@@ -283,6 +283,11 @@ void __init setup_arch(char **cmdline_p)
setup_machine_fdt(__fdt_pointer);
+ /*
+ * Initialise the static keys early as they may be enabled by the
+ * cpufeature code and early parameters.
+ */
+ jump_label_init();
parse_early_param();
/*
--- a/arch/arm64/kernel/smp.c~arm64-move-jump_label_init-before-parse_early_param
+++ a/arch/arm64/kernel/smp.c
@@ -420,11 +420,6 @@ void __init smp_cpus_done(unsigned int m
void __init smp_prepare_boot_cpu(void)
{
set_my_cpu_offset(per_cpu_offset(smp_processor_id()));
- /*
- * Initialise the static keys early as they may be enabled by the
- * cpufeature code.
- */
- jump_label_init();
cpuinfo_store_boot_cpu();
/*
_
