diff options
author | Tvrtko Ursulin <tvrtko.ursulin@intel.com> | 2022-10-03 17:04:02 +0100 |
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committer | Tvrtko Ursulin <tvrtko.ursulin@intel.com> | 2022-10-03 17:04:02 +0100 |
commit | 97acb6a8fcc4e5c2cdc2693a35acdc5a7461aaa3 (patch) | |
tree | c4f1a18b38d655b7806a72515992bd9aae14ef53 /lib/vsprintf.c | |
parent | 6fa964c045a6bc3321a9186e87bfbcfd1059b0f1 (diff) | |
parent | 7860d720a84c74b2761c6b7995392a798ab0a3cb (diff) |
Merge drm/drm-next into drm-intel-gt-next
Daniele needs 84d4333c1e28 ("misc/mei: Add NULL check to component match
callback functions") in order to merge the DG2 HuC patches.
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Diffstat (limited to 'lib/vsprintf.c')
-rw-r--r-- | lib/vsprintf.c | 64 |
1 files changed, 20 insertions, 44 deletions
diff --git a/lib/vsprintf.c b/lib/vsprintf.c index 40d26a07a1331..3c1853a9d1c09 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -750,61 +750,37 @@ static int __init debug_boot_weak_hash_enable(char *str) } early_param("debug_boot_weak_hash", debug_boot_weak_hash_enable); -static DEFINE_STATIC_KEY_TRUE(not_filled_random_ptr_key); -static siphash_key_t ptr_key __read_mostly; +static DEFINE_STATIC_KEY_FALSE(filled_random_ptr_key); static void enable_ptr_key_workfn(struct work_struct *work) { - get_random_bytes(&ptr_key, sizeof(ptr_key)); - /* Needs to run from preemptible context */ - static_branch_disable(¬_filled_random_ptr_key); + static_branch_enable(&filled_random_ptr_key); } -static DECLARE_WORK(enable_ptr_key_work, enable_ptr_key_workfn); - -static int fill_random_ptr_key(struct notifier_block *nb, - unsigned long action, void *data) +/* Maps a pointer to a 32 bit unique identifier. */ +static inline int __ptr_to_hashval(const void *ptr, unsigned long *hashval_out) { - /* This may be in an interrupt handler. */ - queue_work(system_unbound_wq, &enable_ptr_key_work); - return 0; -} - -static struct notifier_block random_ready = { - .notifier_call = fill_random_ptr_key -}; + static siphash_key_t ptr_key __read_mostly; + unsigned long hashval; -static int __init initialize_ptr_random(void) -{ - int key_size = sizeof(ptr_key); - int ret; + if (!static_branch_likely(&filled_random_ptr_key)) { + static bool filled = false; + static DEFINE_SPINLOCK(filling); + static DECLARE_WORK(enable_ptr_key_work, enable_ptr_key_workfn); + unsigned long flags; - /* Use hw RNG if available. */ - if (get_random_bytes_arch(&ptr_key, key_size) == key_size) { - static_branch_disable(¬_filled_random_ptr_key); - return 0; - } + if (!system_unbound_wq || !rng_is_initialized() || + !spin_trylock_irqsave(&filling, flags)) + return -EAGAIN; - ret = register_random_ready_notifier(&random_ready); - if (!ret) { - return 0; - } else if (ret == -EALREADY) { - /* This is in preemptible context */ - enable_ptr_key_workfn(&enable_ptr_key_work); - return 0; + if (!filled) { + get_random_bytes(&ptr_key, sizeof(ptr_key)); + queue_work(system_unbound_wq, &enable_ptr_key_work); + filled = true; + } + spin_unlock_irqrestore(&filling, flags); } - return ret; -} -early_initcall(initialize_ptr_random); - -/* Maps a pointer to a 32 bit unique identifier. */ -static inline int __ptr_to_hashval(const void *ptr, unsigned long *hashval_out) -{ - unsigned long hashval; - - if (static_branch_unlikely(¬_filled_random_ptr_key)) - return -EAGAIN; #ifdef CONFIG_64BIT hashval = (unsigned long)siphash_1u64((u64)ptr, &ptr_key); |