On Wed, Nov 24, 2021 at 01:23:42PM +0000, Matthew Wilcox wrote:

On Wed, Nov 24, 2021 at 03:08:49AM +0000, cgel.zte@gmail.com wrote:

quoted

From: chiminghao <redacted>

Fix the following coccinelle report:
./mm/memory_hotplug.c:2210:2-5:
WARNING  Use BUG_ON instead of if condition followed by BUG.

What coccinelle script is reporting this?

Maybe I found it?

scripts/coccinelle/misc/bugon.cocci:msg="WARNING: Use BUG_ON instead of if condition followed by BUG.\nPlease make sure the condition has no side effects (see conditional BUG_ON definition in include/asm-generic/bug.h)"

Julia, Michal, can we delete this script, please?  It's being abused.

quoted

-	if (try_remove_memory(start, size))
-		BUG();
+	BUG_ON(try_remove_memory(start, size));

I really, really, really do not like this.  For functions with
side-effects, this is bad style.  If it's a pure predicate, then
sure, but this is bad.