net: Revert the softirq will run annotation in ____napi_schedule().

The lockdep annotation lockdep_assert_softirq_will_run() expects that
either hard or soft interrupts are disabled because both guaranty that
the "raised" soft-interrupts will be processed once the context is left.

This triggers in flush_smp_call_function_from_idle() but it this case it
explicitly calls do_softirq() in case of pending softirqs.

Revert the "softirq will run" annotation in ____napi_schedule() and move
the check back to __netif_rx() as it was. Keep the IRQ-off assert in
____napi_schedule() because this is always required.

Fixes: fbd9a2ceba5c7 ("net: Add lockdep asserts to ____napi_schedule().")
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Jason A. Donenfeld <Jason@zx2c4.com>
Link: https://lore.kernel.org/r/YjhD3ZKWysyw8rc6@linutronix.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h
index 0cc65d2..467b942 100644 (file)
--- a/include/linux/lockdep.h
+++ b/include/linux/lockdep.h
@@ -329,12 +329,6 @@ extern void lock_unpin_lock(struct lockdep_map *lock, struct pin_cookie);
 
 #define lockdep_assert_none_held_once()                \
        lockdep_assert_once(!current->lockdep_depth)
-/*
- * Ensure that softirq is handled within the callchain and not delayed and
- * handled by chance.
- */
-#define lockdep_assert_softirq_will_run()      \
-       lockdep_assert_once(hardirq_count() | softirq_count())
 
 #define lockdep_recursing(tsk) ((tsk)->lockdep_recursion)
 
@@ -420,7 +414,6 @@ extern int lockdep_is_held(const void *);
 #define lockdep_assert_held_read(l)            do { (void)(l); } while (0)
 #define lockdep_assert_held_once(l)            do { (void)(l); } while (0)
 #define lockdep_assert_none_held_once()        do { } while (0)
-#define lockdep_assert_softirq_will_run()      do { } while (0)
 
 #define lockdep_recursing(tsk)                 (0)
 

diff --git a/net/core/dev.c b/net/core/dev.c
index 8e0cc5f..8a51094 100644 (file)
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -4277,7 +4277,6 @@ static inline void ____napi_schedule(struct softnet_data *sd,
 {
        struct task_struct *thread;
 
-       lockdep_assert_softirq_will_run();
        lockdep_assert_irqs_disabled();
 
        if (test_bit(NAPI_STATE_THREADED, &napi->state)) {
@@ -4887,7 +4886,7 @@ int __netif_rx(struct sk_buff *skb)
 {
        int ret;
 
-       lockdep_assert_softirq_will_run();
+       lockdep_assert_once(hardirq_count() | softirq_count());
 
        trace_netif_rx_entry(skb);
        ret = netif_rx_internal(skb);