powerpc/code-patching: Remove #ifdef CONFIG_STRICT_KERNEL_RWX

No need to have one implementation of patch_instruction() for
CONFIG_STRICT_KERNEL_RWX and one for !CONFIG_STRICT_KERNEL_RWX.

In patch_instruction(), call raw_patch_instruction() when
!CONFIG_STRICT_KERNEL_RWX.

In poking_init(), bail out immediately, it will be equivalent
to the weak default implementation.

Everything else is declared static and will be discarded by
GCC when !CONFIG_STRICT_KERNEL_RWX.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/f67d2a109404d03e8fdf1ea15388c8778337a76b.1669969781.git.christophe.leroy@csgroup.eu

diff --git a/arch/powerpc/lib/code-patching.c b/arch/powerpc/lib/code-patching.c
index 5b8f87d..a6a5047 100644 (file)
--- a/arch/powerpc/lib/code-patching.c
+++ b/arch/powerpc/lib/code-patching.c
@@ -46,8 +46,6 @@ int raw_patch_instruction(u32 *addr, ppc_inst_t instr)
        return __patch_instruction(addr, instr, addr);
 }
 
-#ifdef CONFIG_STRICT_KERNEL_RWX
-
 struct patch_context {
        union {
                struct vm_struct *area;
@@ -208,6 +206,9 @@ void __init poking_init(void)
 {
        int ret;
 
+       if (!IS_ENABLED(CONFIG_STRICT_KERNEL_RWX))
+               return;
+
        if (mm_patch_enabled())
                ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN,
                                        "powerpc/text_poke_mm:online",
@@ -358,7 +359,8 @@ static int do_patch_instruction(u32 *addr, ppc_inst_t instr)
         * when text_poke_area is not ready, but we still need
         * to allow patching. We just do the plain old patching
         */
-       if (!static_branch_likely(&poking_init_done))
+       if (!IS_ENABLED(CONFIG_STRICT_KERNEL_RWX) ||
+           !static_branch_likely(&poking_init_done))
                return raw_patch_instruction(addr, instr);
 
        local_irq_save(flags);
@@ -370,14 +372,6 @@ static int do_patch_instruction(u32 *addr, ppc_inst_t instr)
 
        return err;
 }
-#else /* !CONFIG_STRICT_KERNEL_RWX */
-
-static int do_patch_instruction(u32 *addr, ppc_inst_t instr)
-{
-       return raw_patch_instruction(addr, instr);
-}
-
-#endif /* CONFIG_STRICT_KERNEL_RWX */
 
 __ro_after_init DEFINE_STATIC_KEY_FALSE(init_mem_is_free);