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Subject: Re: splice: infinite busy loop lockup bug
To:     Matthew Wilcox <willy@infradead.org>,
        Ming Lei <ming.lei@redhat.com>
Cc:     Al Viro <viro@zeniv.linux.org.uk>, syzkaller-bugs@googlegroups.com,
        syzbot <syzbot+61acc40a49a3e46e25ea@syzkaller.appspotmail.com>,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        Dmitry Vyukov <dvyukov@google.com>
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On 2020/08/07 23:11, Matthew Wilcox wrote:
> (I find the whole bvec handling a mess of confusing macros and would
> welcome more of it being inline functions, in general).

Indeed. Inlined functions will be more useful than macros when syzbot
calculates the location of the source code from address for reporting.
I spent a lot of time where

  RIP: 0010:iov_iter_alignment+0x39e/0x850 lib/iov_iter.c:1236

within the complicated macros is. If inlined line numbers were available,
I could have narrowed down the location of infinite loop faster...