diff options
| author |  Ard Biesheuvel <ardb@kernel.org>
| 2022-06-15 17:41:41 +0200 |
|---|---|---|
| committer |  Peter Zijlstra <peterz@infradead.org>
| 2022-06-24 09:48:55 +0200 |
| commit | fdfd42892f311e2b3695852036e5be23661dc590 (patch) | |
| tree | 52a8521d8454ca3da3d0ff416d541909627ba9f4 /arch/mips | |
| parent | jump_label: s390: avoid pointless initial NOP patching (diff) | |
| download | linux-fdfd42892f311e2b3695852036e5be23661dc590.tar.gz linux-fdfd42892f311e2b3695852036e5be23661dc590.tar.bz2 linux-fdfd42892f311e2b3695852036e5be23661dc590.zip | |
jump_label: mips: move module NOP patching into arch code
MIPS is the only remaining architecture that needs to patch jump label
NOP encodings to initialize them at load time. So let's move the module
patching part of that from generic code into arch/mips, and drop it from
the others.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220615154142.1574619-3-ardb@kernel.org
Diffstat (limited to 'arch/mips')
| -rw-r--r-- | arch/mips/kernel/jump_label.c | 19 | ||||
| -rw-r--r-- | arch/mips/kernel/module.c | 5 |
2 files changed, 22 insertions, 2 deletions
diff --git a/arch/mips/kernel/jump_label.c b/arch/mips/kernel/jump_label.c index 662c8db9f45b..71a882c8c6eb 100644 --- a/arch/mips/kernel/jump_label.c +++ b/arch/mips/kernel/jump_label.c @@ -88,3 +88,22 @@ void arch_jump_label_transform(struct jump_entry *e, mutex_unlock(&text_mutex); } + +#ifdef CONFIG_MODULES +void jump_label_apply_nops(struct module *mod) +{ + struct jump_entry *iter_start = mod->jump_entries; + struct jump_entry *iter_stop = iter_start + mod->num_jump_entries; + struct jump_entry *iter; + + /* if the module doesn't have jump label entries, just return */ + if (iter_start == iter_stop) + return; + + for (iter = iter_start; iter < iter_stop; iter++) { + /* Only write NOPs for arch_branch_static(). */ + if (jump_label_init_type(iter) == JUMP_LABEL_NOP) + arch_jump_label_transform(iter, JUMP_LABEL_NOP); + } +} +#endif diff --git a/arch/mips/kernel/module.c b/arch/mips/kernel/module.c index 14f46d17500a..0c936cbf20c5 100644 --- a/arch/mips/kernel/module.c +++ b/arch/mips/kernel/module.c @@ -21,6 +21,7 @@ #include <linux/spinlock.h> #include <linux/jump_label.h> +extern void jump_label_apply_nops(struct module *mod); struct mips_hi16 { struct mips_hi16 *next; @@ -428,8 +429,8 @@ int module_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *s; char *secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset; - /* Make jump label nops. */ - jump_label_apply_nops(me); + if (IS_ENABLED(CONFIG_JUMP_LABEL)) + jump_label_apply_nops(me); INIT_LIST_HEAD(&me->arch.dbe_list); for (s = sechdrs; s < sechdrs + hdr->e_shnum; s++) { |