On 06/22/2015 12:12 AM, Al Viro wrote: > On Thu, Apr 23, 2015 at 01:16:15PM +0300, Andrey Ryabinin wrote: >> This change caused following: > >> This could happen when p9pdu_readf() changes 'count' to some value > iov_iter_count(from): >> >> p9_client_write(): >> <...> >> int count = iov_iter_count(from); >> <...> >> *err = p9pdu_readf(req->rc, clnt->proto_version, "d", &count); >> <...> >> iov_iter_advance(from, count); > > *blink* > > That's a bug, all right, but I would love to see how you trigger it. > It would require server to respond to "write that many bytes" with "OK, > <greater number> bytes written". We certainly need to cope with that > (we can't trust the server to be sane), but if that's what is going on, > you've got a server bug as well. > > Could you check if the patch below triggers WARN_ON() in it on your > reproducer? p9_client_read() has a similar issue as well... > I've tried something like your patch before to check the read side and I haven't seen anything before and don't see it right now. Though, this doesn't mean that there is no problem with read. I mean that trinity hits this on write and may just not hit this on read. -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in
