Messages in this thread Patch in this message | | | From | Benjamin Tissoires <> | Date | Mon, 22 Apr 2024 09:16:28 +0200 | Subject | [PATCH] bpf: verifier: allow arrays of progs to be used in sleepable context |
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Arrays of progs are underlying using regular arrays, but they can only be updated from a syscall. Therefore, they should be safe to use while in a sleepable context.
This is required to be able to call bpf_tail_call() from a sleepable tracing bpf program.
Signed-off-by: Benjamin Tissoires <bentiss@kernel.org> --- Hi,
a small patch to allow to have:
``` SEC("fmod_ret.s/__hid_bpf_tail_call_sleepable") int BPF_PROG(hid_tail_call_sleepable, struct hid_bpf_ctx *hctx) { bpf_tail_call(ctx, &hid_jmp_table, hctx->index);
return 0; } ```
This should allow me to add bpf hooks to functions that communicate with the hardware.
Cheers, Benjamin --- kernel/bpf/verifier.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 68cfd6fc6ad4..880b32795136 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -18171,6 +18171,7 @@ static int check_map_prog_compatibility(struct bpf_verifier_env *env, case BPF_MAP_TYPE_QUEUE: case BPF_MAP_TYPE_STACK: case BPF_MAP_TYPE_ARENA: + case BPF_MAP_TYPE_PROG_ARRAY: break; default: verbose(env, --- base-commit: 735f5b8a7ccf383e50d76f7d1c25769eee474812 change-id: 20240422-sleepable_array_progs-e0c07b17cabb Best regards, -- Benjamin Tissoires <bentiss@kernel.org>
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