Commit-ID: 4cc6620b5e4c8953c725bcfab86a57df01e83a7c Gitweb: https://git.kernel.org/tip/4cc6620b5e4c8953c725bcfab86a57df01e83a7c Author: Daniel Bristot de Oliveira <bris...@redhat.com> AuthorDate: Wed, 12 Jun 2019 11:57:27 +0200 Committer: Ingo Molnar <mi...@kernel.org> CommitDate: Mon, 17 Jun 2019 12:09:20 +0200
x86/jump_label: Add a __jump_label_set_jump_code() helper Move the definition of the code to be written from __jump_label_transform() to a specialized function. No functional change. Signed-off-by: Daniel Bristot de Oliveira <bris...@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <pet...@infradead.org> Cc: Borislav Petkov <b...@alien8.de> Cc: Chris von Recklinghausen <creck...@redhat.com> Cc: Clark Williams <willi...@redhat.com> Cc: Greg Kroah-Hartman <gre...@linuxfoundation.org> Cc: H. Peter Anvin <h...@zytor.com> Cc: Jason Baron <jba...@akamai.com> Cc: Jiri Kosina <jkos...@suse.cz> Cc: Josh Poimboeuf <jpoim...@redhat.com> Cc: Linus Torvalds <torva...@linux-foundation.org> Cc: Marcelo Tosatti <mtosa...@redhat.com> Cc: Masami Hiramatsu <mhira...@kernel.org> Cc: Peter Zijlstra <pet...@infradead.org> Cc: Scott Wood <sw...@redhat.com> Cc: Steven Rostedt (VMware) <rost...@goodmis.org> Cc: Thomas Gleixner <t...@linutronix.de> Link: https://lkml.kernel.org/r/d2f52a0010ecd399cf9b02a65bcf5836571b9e52.1560325897.git.bris...@redhat.com Signed-off-by: Ingo Molnar <mi...@kernel.org> --- arch/x86/kernel/jump_label.c | 52 +++++++++++++++++++++++--------------------- 1 file changed, 27 insertions(+), 25 deletions(-) diff --git a/arch/x86/kernel/jump_label.c b/arch/x86/kernel/jump_label.c index e631c358f7f4..f33408f1c3f6 100644 --- a/arch/x86/kernel/jump_label.c +++ b/arch/x86/kernel/jump_label.c @@ -35,41 +35,43 @@ static void bug_at(unsigned char *ip, int line) BUG(); } -static void __ref __jump_label_transform(struct jump_entry *entry, - enum jump_label_type type, - int init) +static void __jump_label_set_jump_code(struct jump_entry *entry, + enum jump_label_type type, + union jump_code_union *code, + int init) { - union jump_code_union jmp; const unsigned char default_nop[] = { STATIC_KEY_INIT_NOP }; const unsigned char *ideal_nop = ideal_nops[NOP_ATOMIC5]; - const void *expect, *code; + const void *expect; int line; - jmp.jump = 0xe9; - jmp.offset = jump_entry_target(entry) - - (jump_entry_code(entry) + JUMP_LABEL_NOP_SIZE); - - if (type == JUMP_LABEL_JMP) { - if (init) { - expect = default_nop; line = __LINE__; - } else { - expect = ideal_nop; line = __LINE__; - } + code->jump = 0xe9; + code->offset = jump_entry_target(entry) - + (jump_entry_code(entry) + JUMP_LABEL_NOP_SIZE); - code = &jmp.code; + if (init) { + expect = default_nop; line = __LINE__; + } else if (type == JUMP_LABEL_JMP) { + expect = ideal_nop; line = __LINE__; } else { - if (init) { - expect = default_nop; line = __LINE__; - } else { - expect = &jmp.code; line = __LINE__; - } - - code = ideal_nop; + expect = code->code; line = __LINE__; } if (memcmp((void *)jump_entry_code(entry), expect, JUMP_LABEL_NOP_SIZE)) bug_at((void *)jump_entry_code(entry), line); + if (type == JUMP_LABEL_NOP) + memcpy(code, ideal_nop, JUMP_LABEL_NOP_SIZE); +} + +static void __ref __jump_label_transform(struct jump_entry *entry, + enum jump_label_type type, + int init) +{ + union jump_code_union code; + + __jump_label_set_jump_code(entry, type, &code, init); + /* * As long as only a single processor is running and the code is still * not marked as RO, text_poke_early() can be used; Checking that @@ -82,12 +84,12 @@ static void __ref __jump_label_transform(struct jump_entry *entry, * always nop being the 'currently valid' instruction */ if (init || system_state == SYSTEM_BOOTING) { - text_poke_early((void *)jump_entry_code(entry), code, + text_poke_early((void *)jump_entry_code(entry), &code, JUMP_LABEL_NOP_SIZE); return; } - text_poke_bp((void *)jump_entry_code(entry), code, JUMP_LABEL_NOP_SIZE, + text_poke_bp((void *)jump_entry_code(entry), &code, JUMP_LABEL_NOP_SIZE, (void *)jump_entry_code(entry) + JUMP_LABEL_NOP_SIZE); }
