Revert "bpf: Fix potential call bpf_link_free() in atomic context"

This reverts commit 31f23a6a181c81543b10a1a9056b0e6c7ef1c747.

This change made many selftests/bpf flaky: flow_dissector, sk_lookup, sk_assign and others.
There was no issue in the code.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>

diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 3426849..2740df1 100644 (file)
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -2345,8 +2345,12 @@ void bpf_link_put(struct bpf_link *link)
        if (!atomic64_dec_and_test(&link->refcnt))
                return;
 
-       INIT_WORK(&link->work, bpf_link_put_deferred);
-       schedule_work(&link->work);
+       if (in_atomic()) {
+               INIT_WORK(&link->work, bpf_link_put_deferred);
+               schedule_work(&link->work);
+       } else {
+               bpf_link_free(link);
+       }
 }
 
 static int bpf_link_release(struct inode *inode, struct file *filp)