Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
io_uring/napi: fix io_napi_entry RCU accesses
correct 3 RCU structures modifications that were not using the RCU
functions to make their update.
Signed-off-by: Olivier Langlois <olivier@trillion01.com>
Link: https://lore.kernel.org/r/9f53b5169afa8c7bf3665a0b19dc2f7061173530.1728828877.git.olivier@trillion01.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
authored by
Olivier Langlois
and committed by
Jens Axboe
45b3941d
2f3cc8e4
+11
-6
+11
-6
io_uring/napi.c
+11
-6
io_uring/napi.c
···
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}
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hlist_add_tail_rcu(&e->node, hash_list);
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-
list_add_tail(&e->list, &ctx->napi_list);
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+
list_add_tail_rcu(&e->list, &ctx->napi_list);
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spin_unlock(&ctx->napi_lock);
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}
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static void __io_napi_remove_stale(struct io_ring_ctx *ctx)
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{
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struct io_napi_entry *e;
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-
unsigned int i;
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spin_lock(&ctx->napi_lock);
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-
hash_for_each(ctx->napi_ht, i, e, node) {
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+
/*
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* list_for_each_entry_safe() is not required as long as:
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+
* 1. list_del_rcu() does not reset the deleted node next pointer
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* 2. kfree_rcu() delays the memory freeing until the next quiescent
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+
* state
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*/
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list_for_each_entry(e, &ctx->napi_list, list) {
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if (time_after(jiffies, READ_ONCE(e->timeout))) {
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-
list_del(&e->list);
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+
list_del_rcu(&e->list);
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hash_del_rcu(&e->node);
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kfree_rcu(e, rcu);
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}
···
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void io_napi_free(struct io_ring_ctx *ctx)
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{
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struct io_napi_entry *e;
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-
unsigned int i;
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spin_lock(&ctx->napi_lock);
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-
hash_for_each(ctx->napi_ht, i, e, node) {
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+
list_for_each_entry(e, &ctx->napi_list, list) {
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hash_del_rcu(&e->node);
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kfree_rcu(e, rcu);
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}
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+
INIT_LIST_HEAD_RCU(&ctx->napi_list);
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spin_unlock(&ctx->napi_lock);
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}
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