From: Sebastian Andrzej Siewior Date: Fri, 19 Aug 2022 11:24:38 +0200 Subject: [PATCH 341/351] random: Bring back the local_locks Origin: https://git.kernel.org/cgit/linux/kernel/git/rt/linux-stable-rt.git/commit?id=269eda25b7a58b0397934d72f6fef03f0301d696 As part of the backports the random code lost its local_lock_t type and the whole operation became a local_irq_{disable|enable}() simply because the older kernel did not provide those primitives. RT as of v4.9 has a slightly different variant of local_locks. Replace the local_irq_*() operations with matching local_lock_irq*() operations which were there as part of commit 77760fd7f7ae3 ("random: remove batched entropy locking") Signed-off-by: Sebastian Andrzej Siewior Link: https://lore.kernel.org/all/20220819092446.980320-2-bigeasy@linutronix.de/ Signed-off-by: Daniel Wagner --- drivers/char/random.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/drivers/char/random.c b/drivers/char/random.c index 6aea12fa48ba..be2b7520ade9 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -53,6 +53,7 @@ #include #include #include +#include #include #include #include @@ -229,10 +230,12 @@ static struct { struct crng { u8 key[CHACHA20_KEY_SIZE]; unsigned long generation; + struct local_irq_lock lock; }; static DEFINE_PER_CPU(struct crng, crngs) = { - .generation = ULONG_MAX + .generation = ULONG_MAX, + .lock.lock = __SPIN_LOCK_UNLOCKED(crngs.lock.lock), }; /* Used by crng_reseed() and crng_make_state() to extract a new seed from the input pool. */ @@ -362,7 +365,7 @@ static void crng_make_state(u32 chacha_state[CHACHA20_BLOCK_SIZE / sizeof(u32)], if (unlikely(crng_has_old_seed())) crng_reseed(); - local_irq_save(flags); + local_lock_irqsave(crngs.lock, flags); crng = raw_cpu_ptr(&crngs); /* @@ -387,7 +390,7 @@ static void crng_make_state(u32 chacha_state[CHACHA20_BLOCK_SIZE / sizeof(u32)], * should wind up here immediately. */ crng_fast_key_erasure(crng->key, chacha_state, random_data, random_data_len); - local_irq_restore(flags); + local_unlock_irqrestore(crngs.lock, flags); } static void _get_random_bytes(void *buf, size_t len) @@ -505,11 +508,13 @@ struct batch_ ##type { \ * formula of (integer_blocks + 0.5) * CHACHA20_BLOCK_SIZE. \ */ \ type entropy[CHACHA20_BLOCK_SIZE * 3 / (2 * sizeof(type))]; \ + struct local_irq_lock lock; \ unsigned long generation; \ unsigned int position; \ }; \ \ static DEFINE_PER_CPU(struct batch_ ##type, batched_entropy_ ##type) = { \ + .lock.lock = __SPIN_LOCK_UNLOCKED(batched_entropy_ ##type.lock.lock), \ .position = UINT_MAX \ }; \ \ @@ -527,7 +532,7 @@ type get_random_ ##type(void) \ return ret; \ } \ \ - local_irq_save(flags); \ + local_lock_irqsave(batched_entropy_ ##type.lock, flags); \ batch = raw_cpu_ptr(&batched_entropy_##type); \ \ next_gen = READ_ONCE(base_crng.generation); \ @@ -541,7 +546,7 @@ type get_random_ ##type(void) \ ret = batch->entropy[batch->position]; \ batch->entropy[batch->position] = 0; \ ++batch->position; \ - local_irq_restore(flags); \ + local_unlock_irqrestore(batched_entropy_ ##type.lock, flags); \ return ret; \ } \ EXPORT_SYMBOL(get_random_ ##type);