Commit-ID: e1aacb3f4adc1bcd4273a1d538a2dc3e50f1cbb5 Gitweb: https://git.kernel.org/tip/e1aacb3f4adc1bcd4273a1d538a2dc3e50f1cbb5 Author: Daniel Bristot de Oliveira <bris...@redhat.com> AuthorDate: Wed, 12 Jun 2019 11:57:26 +0200 Committer: Ingo Molnar <mi...@kernel.org> CommitDate: Mon, 17 Jun 2019 12:09:19 +0200
jump_label: Add a jump_label_can_update() helper Move the check if a jump_entry is valid to a 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/56b69bd3f8e644ed64f2dbde7c088030b8cbe76b.1560325897.git.bris...@redhat.com Signed-off-by: Ingo Molnar <mi...@kernel.org> --- kernel/jump_label.c | 29 ++++++++++++++++++----------- 1 file changed, 18 insertions(+), 11 deletions(-) diff --git a/kernel/jump_label.c b/kernel/jump_label.c index 0bfa10f4410c..24f0d3b1526b 100644 --- a/kernel/jump_label.c +++ b/kernel/jump_label.c @@ -384,23 +384,30 @@ static enum jump_label_type jump_label_type(struct jump_entry *entry) return enabled ^ branch; } +static bool jump_label_can_update(struct jump_entry *entry, bool init) +{ + /* + * Cannot update code that was in an init text area. + */ + if (!init && jump_entry_is_init(entry)) + return false; + + if (!kernel_text_address(jump_entry_code(entry))) { + WARN_ONCE(1, "can't patch jump_label at %pS", (void *)jump_entry_code(entry)); + return false; + } + + return true; +} + static void __jump_label_update(struct static_key *key, struct jump_entry *entry, struct jump_entry *stop, bool init) { for (; (entry < stop) && (jump_entry_key(entry) == key); entry++) { - /* - * An entry->code of 0 indicates an entry which has been - * disabled because it was in an init text area. - */ - if (init || !jump_entry_is_init(entry)) { - if (kernel_text_address(jump_entry_code(entry))) - arch_jump_label_transform(entry, jump_label_type(entry)); - else - WARN_ONCE(1, "can't patch jump_label at %pS", - (void *)jump_entry_code(entry)); - } + if (jump_label_can_update(entry, init)) + arch_jump_label_transform(entry, jump_label_type(entry)); } }
