[GIT PULL] locking fixes

From: Ingo Molnar
Date: Sun Dec 27 2020 - 05:08:41 EST


Linus,

Please pull the latest locking/urgent git tree from:

git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git locking-urgent-2020-12-27

# HEAD: 91ea62d58bd661827c328a2c6c02a87fa4aae88b softirq: Avoid bad tracing / lockdep interaction

Misc fixes/updates:

- Fix static keys usage in module __init sections
- Add separate MAINTAINERS entry for static branches/calls
- Fix lockdep splat with CONFIG_PREEMPTIRQ_EVENTS=y tracing

Thanks,

Ingo

------------------>
Peter Zijlstra (3):
jump_label: Fix usage in module __init
jump_label/static_call: Add MAINTAINERS
softirq: Avoid bad tracing / lockdep interaction


MAINTAINERS | 16 ++++++++++++++++
kernel/jump_label.c | 8 +++++---
kernel/softirq.c | 2 +-
3 files changed, 22 insertions(+), 4 deletions(-)

diff --git a/MAINTAINERS b/MAINTAINERS
index 281de213ef47..be02614ad28d 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -16675,6 +16675,22 @@ M: Ion Badulescu <ionut@xxxxxxxxxx>
S: Odd Fixes
F: drivers/net/ethernet/adaptec/starfire*

+STATIC BRANCH/CALL
+M: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
+M: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
+M: Jason Baron <jbaron@xxxxxxxxxx>
+R: Steven Rostedt <rostedt@xxxxxxxxxxx>
+R: Ard Biesheuvel <ardb@xxxxxxxxxx>
+S: Supported
+F: arch/*/include/asm/jump_label*.h
+F: arch/*/include/asm/static_call*.h
+F: arch/*/kernel/jump_label.c
+F: arch/*/kernel/static_call.c
+F: include/linux/jump_label*.h
+F: include/linux/static_call*.h
+F: kernel/jump_label.c
+F: kernel/static_call.c
+
STEC S1220 SKD DRIVER
M: Damien Le Moal <Damien.LeMoal@xxxxxxx>
L: linux-block@xxxxxxxxxxxxxxx
diff --git a/kernel/jump_label.c b/kernel/jump_label.c
index 015ef903ce8c..c6a39d662935 100644
--- a/kernel/jump_label.c
+++ b/kernel/jump_label.c
@@ -793,6 +793,7 @@ int jump_label_text_reserved(void *start, void *end)
static void jump_label_update(struct static_key *key)
{
struct jump_entry *stop = __stop___jump_table;
+ bool init = system_state < SYSTEM_RUNNING;
struct jump_entry *entry;
#ifdef CONFIG_MODULES
struct module *mod;
@@ -804,15 +805,16 @@ static void jump_label_update(struct static_key *key)

preempt_disable();
mod = __module_address((unsigned long)key);
- if (mod)
+ if (mod) {
stop = mod->jump_entries + mod->num_jump_entries;
+ init = mod->state == MODULE_STATE_COMING;
+ }
preempt_enable();
#endif
entry = static_key_entries(key);
/* if there are no users, entry can be NULL */
if (entry)
- __jump_label_update(key, entry, stop,
- system_state < SYSTEM_RUNNING);
+ __jump_label_update(key, entry, stop, init);
}

#ifdef CONFIG_STATIC_KEYS_SELFTEST
diff --git a/kernel/softirq.c b/kernel/softirq.c
index 09229ad82209..0f1d3a32d53b 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -185,7 +185,7 @@ void __local_bh_enable_ip(unsigned long ip, unsigned int cnt)
* Keep preemption disabled until we are done with
* softirq processing:
*/
- preempt_count_sub(cnt - 1);
+ __preempt_count_sub(cnt - 1);

if (unlikely(!in_interrupt() && local_softirq_pending())) {
/*