On Tue, Feb 16, 2021 at 8:37 PM Dan Carpenter <dan.carpenter@xxxxxxxxxx> wrote: > > The WARN_ON() argument is a condition, and it generates a stack trace > but it doesn't print the warning. > > Fixes: 4ddb74165ae5 ("bpf: Extract nullable reg type conversion into a helper function") > Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> > --- > kernel/bpf/verifier.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c > index 056df6be3e30..bd4d1dfca73c 100644 > --- a/kernel/bpf/verifier.c > +++ b/kernel/bpf/verifier.c > @@ -1120,7 +1120,7 @@ static void mark_ptr_not_null_reg(struct bpf_reg_state *reg) > reg->type = PTR_TO_RDWR_BUF; > break; > default: > - WARN_ON("unknown nullable register type"); > + WARN(1, "unknown nullable register type"); Should we use WARN_ONCE here? Also, I think the fix should be targeted for bpf-next as the patch that introduced this hasn't made it to bpf yet. [...]