Hi, Is there any specific reason for which io_close_prep returns EBADF if using REQ_F_FIXED_FILE? I discovered my software was failing to close sockets when using fixed files a while ago but I put it to the side, initially thinking it was a bug I introduced in my code. In recent days I picked it up again and after investigating it, it looks like that, instead, that's the expected behaviour. >From what I see, although the behaviour was slightly changed with a couple of commits (ie. with https://github.com/torvalds/linux/commit/cf3040ca55f2085b0a372a620ee2cb93ae19b686 ) the io_close_prep have had this behaviour from the very beginning https://github.com/torvalds/linux/commit/b5dba59e0cf7e2cc4d3b3b1ac5fe81ddf21959eb . @Jens during my researches I have also found https://lkml.org/lkml/2020/5/7/1575 where there is a patch that allows, at least from what it looks like at a first glance, fixed files with io_close_prep but seems that the email thread died there. Shouldn't the close op match the behaviour of the other I/O related ops when it comes to fds? If there aren't specific reasons, happy to look into it and write a patch. Thanks, Daniele
