On 7/1/21 3:01 PM, Daniele Salvatore Albano wrote: > On Thu, 1 Jul 2021 at 00:28, Pavel Begunkov <asml.silence@xxxxxxxxx> wrote: >> >> On 6/30/21 10:14 PM, Victor Stewart wrote: >>> i'm fairly confident there is something broken with >>> io_uring_register_files_update, >>> especially the offset parameter. >>> >>> when trying to update a single fd, and getting a successful result of >>> 1, proceeding >>> operations with IOSQE_FIXED_FILE fail with -9. but if i update all of >>> the fds with >>> then my recv operations succeed, but close still fails with -9. >>> >>> on Clear LInux 5.12.13-1050.native >> >> Thanks for letting know, I'll take a look >> [...] > I sent an email a while ago to raise a question about a potential bug > related to close. > > Looks like the close doesn't support registered files (although I saw > some code within a patch from Jens to fix it while I was > investigating). It have never been supported, don't remember it being discussed to be implemented at any point, and the links below are about unrelated things. If you want to close a fixed file, you can use IORING_OP_FILES_UPDATE with fd=-1 instead. Easy enough to add it to close, but not sure I see the reason for that considering existence of IORING_OP_FILES_UPDATE. fwiw, it doesn't sound related to Victor's report, but still need to look at it. > Attached below > > On Fri, 21 May 2021 at 21:28, Daniele Salvatore Albano > <d.albano@xxxxxxxxx> wrote: >> >> 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 -- Pavel Begunkov
