Re: [PATCH] xen: fix: use WARN_ON instead of if condition followed by BUG.

[Roger Pau Monné]

On Wed, Dec 30, 2020 at 02:38:06PM +0800, YANG LI wrote:
> Use WARN_ON instead of if condition followed by BUG in
> gnttab_batch_map() and gnttab_batch_copy().

But those are not equivalent as far as I'm aware. BUG will stop
execution, while WARN_ON will print a splat and continue executing.

If switching to WARN_ON is indeed fine it needs to be explained in the
commit message that returning to the caller(s) with
HYPERVISOR_grant_table_op having returned an error code is fine, and
that it's not going to create other issues, like memory corruption or
leaks.

Thanks, Roger.