[RFC][PATCH 34/34] x86/cpu: Mark new boot CPU and config structures appropriately

Dave Hansen
2024-02-22T18:40:11Z

Just to recap the rules:

1. 'bsp_addr_config' is only used in early boot by the BSP.
2. 'x86_config' is only written once by the BSP and can be
used read-only during normal system operation

Mark 'bsp_addr_config' so it goes away after boot *and* non-init
references to it can be detected and warned about.

Mark 'x86_config' as __ro_after_init so it does not turn into the same
mess that 'boot_cpu_data' is.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
---

b/arch/x86/kernel/setup.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff -puN arch/x86/kernel/setup.c~mark-new-structs arch/x86/kernel/setup.c
--- a/arch/x86/kernel/setup.c~mark-new-structs 2024-02-22 10:09:05.173109438 -0800
+++ b/arch/x86/kernel/setup.c 2024-02-22 10:09:05.177109595 -0800
@@ -131,8 +131,8 @@ struct ist_info ist_info;
struct cpuinfo_x86 boot_cpu_data __read_mostly;
EXPORT_SYMBOL(boot_cpu_data);

-struct x86_addr_config bsp_addr_config;
-struct x86_sys_config x86_config __read_mostly;
+struct x86_addr_config bsp_addr_config __initdata;
+struct x86_sys_config x86_config __ro_after_init;

#if !defined(CONFIG_X86_PAE) || defined(CONFIG_X86_64)
__visible unsigned long mmu_cr4_features __ro_after_init;
_