On 2/16/21 10:10 PM, KP Singh wrote:
On Tue, Feb 16, 2021 at 8:37 PM Dan Carpenter <[email protected]> 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 <[email protected]> --- 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. [...]
Usually we have something like `verbose(env, "kernel subsystem misconfigured verifier\n")`, but in this case we'd need to drag env all the way to here. :/ I agree with WARN_ONCE().

