Pull lockdep fix from Thomas Gleixner: "A RT fix for lockdep. lockdep invokes prandom_u32() to create cookies. This worked until prandom_u32() was switched to the real random generator, which takes a spinlock for extraction, which does not work on RT when invoked from atomic contexts. lockdep has no requirement for real random numbers and it turns out sched_clock() is good enough to create the cookie. That works everywhere and is faster" * tag 'locking-urgent-2022-06-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: locking/lockdep: Use sched_clock() for random numbers
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| @@ -5432,7 +5432,7 @@ static struct pin_cookie __lock_pin_lock(struct lockdep_map *lock) · 5431 unmodified lines | |||
| 5432 | * be guessable and still allows some pin nesting in | 5432 | * be guessable and still allows some pin nesting in |
| 5433 | * our u32 pin_count. | 5433 | * our u32 pin_count. |
| 5434 | */ | 5434 | */ |
| 5435 | cookie.val = 1 + (prandom_u32() >> 16); | 5435 | cookie.val = 1 + (sched_clock() & 0xffff); |
| 5436 | hlock->pin_count += cookie.val; | 5436 | hlock->pin_count += cookie.val; |
| 5437 | return cookie; | 5437 | return cookie; |
| 5438 | } | 5438 | } |