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SubjectRe: [PATCH] bpf_lru_list: Read double-checked variable once without lock
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Hello:

This patch was applied to bpf/bpf-next.git (refs/heads/master):

On Tue, 9 Feb 2021 12:27:01 +0100 you wrote:
> For double-checked locking in bpf_common_lru_push_free(), node->type is
> read outside the critical section and then re-checked under the lock.
> However, concurrent writes to node->type result in data races.
>
> For example, the following concurrent access was observed by KCSAN:
>
> write to 0xffff88801521bc22 of 1 bytes by task 10038 on cpu 1:
> __bpf_lru_node_move_in kernel/bpf/bpf_lru_list.c:91
> __local_list_flush kernel/bpf/bpf_lru_list.c:298
> ...
> read to 0xffff88801521bc22 of 1 bytes by task 10043 on cpu 0:
> bpf_common_lru_push_free kernel/bpf/bpf_lru_list.c:507
> bpf_lru_push_free kernel/bpf/bpf_lru_list.c:555
> ...
>
> [...]

Here is the summary with links:
- bpf_lru_list: Read double-checked variable once without lock
https://git.kernel.org/bpf/bpf-next/c/6df8fb83301d

You are awesome, thank you!
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