Messages in this thread Patch in this message | | | From | Daniel Bristot de Oliveira <> | Subject | [PATCH V5 2/7] jump_label: Add a jump_label_can_update() helper | Date | Mon, 1 Apr 2019 10:58:14 +0200 |
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Move the check if a jump_entry is valid to a function.
Signed-off-by: Daniel Bristot de Oliveira <bristot@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: "Steven Rostedt (VMware)" <rostedt@goodmis.org> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org> Cc: Chris von Recklinghausen <crecklin@redhat.com> Cc: Jason Baron <jbaron@akamai.com> Cc: Scott Wood <swood@redhat.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Clark Williams <williams@redhat.com> Cc: x86@kernel.org Cc: linux-kernel@vger.kernel.org --- kernel/jump_label.c | 28 ++++++++++++++++++---------- 1 file changed, 18 insertions(+), 10 deletions(-)
diff --git a/kernel/jump_label.c b/kernel/jump_label.c index 288d630da22d..e666a4d6642a 100644 --- a/kernel/jump_label.c +++ b/kernel/jump_label.c @@ -374,22 +374,30 @@ 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_each_label_entry(key, entry, stop) { - /* - * 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)); } } } -- 2.20.1
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