Re: [PATCH -next] powerpc/book3s64: fix link error with CONFIG_PPC_RADIX_MMU=n
From: Christophe Leroy <hidden>
Date: 2020-09-06 06:50:33
Also in:
lkml
Le 05/09/2020 à 13:25, Yang Yingliang a écrit :
Fix link error when CONFIG_PPC_RADIX_MMU is disabled: powerpc64-linux-gnu-ld: arch/powerpc/platforms/pseries/lpar.o:(.toc+0x0): undefined reference to `mmu_pid_bits' Reported-by: Hulk Robot <redacted> Signed-off-by: Yang Yingliang <redacted> --- arch/powerpc/mm/book3s64/mmu_context.c | 4 ++++
In your commit log, you are just mentionning arch/powerpc/platforms/pseries/lpar.o, which is right. You shouldn't need to modify arch/powerpc/mm/book3s64/mmu_context.c at all, see below.
quoted hunk ↗ jump to hunk
arch/powerpc/platforms/pseries/lpar.c | 2 ++ 2 files changed, 6 insertions(+)diff --git a/arch/powerpc/mm/book3s64/mmu_context.c b/arch/powerpc/mm/book3s64/mmu_context.c index 0ba30b8b935b..a8e292cd88f0 100644 --- a/arch/powerpc/mm/book3s64/mmu_context.c +++ b/arch/powerpc/mm/book3s64/mmu_context.c@@ -152,6 +152,7 @@ void hash__setup_new_exec(void) static int radix__init_new_context(struct mm_struct *mm) { +#ifdef CONFIG_PPC_RADIX_MMU
This shouldn't be required. radix__init_new_context() is only called when radix_enabled() returns true. As it is a static function, when it is not called it gets optimised away, so you will never get an undefined reference to `mmu_pid_bits` there.
quoted hunk ↗ jump to hunk
unsigned long rts_field; int index, max_id;@@ -177,6 +178,9 @@ static int radix__init_new_context(struct mm_struct *mm) mm->context.hash_context = NULL; return index; +#else + return -ENOTSUPP; +#endif } int init_new_context(struct task_struct *tsk, struct mm_struct *mm)diff --git a/arch/powerpc/platforms/pseries/lpar.c b/arch/powerpc/platforms/pseries/lpar.c index baf24eacd268..e454e218dbba 100644 --- a/arch/powerpc/platforms/pseries/lpar.c +++ b/arch/powerpc/platforms/pseries/lpar.c@@ -1726,10 +1726,12 @@ void __init hpte_init_pseries(void) void radix_init_pseries(void) { +#ifdef CONFIG_PPC_RADIX_MMU
This function is only called from /arch/powerpc/mm/book3s64/radix_pgtable.c which is only built when CONFIG_PPC_RADIX_MMU is selected. So the entire function should be encloded in the #ifdef.
pr_info("Using radix MMU under hypervisor\n");
pseries_lpar_register_process_table(__pa(process_tb),
0, PRTB_SIZE_SHIFT - 12);
+#endif
}
#ifdef CONFIG_PPC_SMLPARChristophe