Reported in the community forum [0]. This fixes an issue with read/write operations done on ocfs2 with io_uring. This has caused QEMU guests to be unable to determine the file format at [1] because of an unsuccessful read and therefore could not boot, which has been resolved with this patch.
This patch is already merged in Jens Axboe's linux-block tree and also merged in the mainline v6.12 prepatch kernels: > # git tag --contains c0a9d496e0fece67db777bd48550376cf2960c47 > v6.12-rc1 > v6.12-rc2 > v6.13-rc3 [0] https://forum.proxmox.com/threads/140273/post-702007 [1] https://elixir.bootlin.com/qemu/v9.0.2/source/block.c#L1031 Signed-off-by: Daniel Kral <d.k...@proxmox.com> --- ...t-EOPNOTSUPP-for-IOCB_NOWAIT-like-EA.patch | 45 +++++++++++++++++++ 1 file changed, 45 insertions(+) create mode 100644 patches/kernel/0021-io_uring-rw-treat-EOPNOTSUPP-for-IOCB_NOWAIT-like-EA.patch diff --git a/patches/kernel/0021-io_uring-rw-treat-EOPNOTSUPP-for-IOCB_NOWAIT-like-EA.patch b/patches/kernel/0021-io_uring-rw-treat-EOPNOTSUPP-for-IOCB_NOWAIT-like-EA.patch new file mode 100644 index 0000000..7187c94 --- /dev/null +++ b/patches/kernel/0021-io_uring-rw-treat-EOPNOTSUPP-for-IOCB_NOWAIT-like-EA.patch @@ -0,0 +1,45 @@ +From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001 +From: Jens Axboe <ax...@kernel.dk> +Date: Tue, 10 Sep 2024 08:30:57 -0600 +Subject: [PATCH] io_uring/rw: treat -EOPNOTSUPP for IOCB_NOWAIT like -EAGAIN + +Some file systems, ocfs2 in this case, will return -EOPNOTSUPP for +an IOCB_NOWAIT read/write attempt. While this can be argued to be +correct, the usual return value for something that requires blocking +issue is -EAGAIN. + +A refactoring io_uring commit dropped calling kiocb_done() for +negative return values, which is otherwise where we already do that +transformation. To ensure we catch it in both spots, check it in +__io_read() itself as well. + +Reported-by: Robert Sander <r.san...@heinlein-support.de> +Link: https://fosstodon.org/@gurub...@mastodon.gurubert.de/113112431889638440 +Cc: sta...@vger.kernel.org +Fixes: a08d195b586a ("io_uring/rw: split io_read() into a helper") +Signed-off-by: Jens Axboe <ax...@kernel.dk> +(cherry picked from commit c0a9d496e0fece67db777bd48550376cf2960c47) +Signed-off-by: Daniel Kral <d.k...@proxmox.com> +--- + io_uring/rw.c | 8 ++++++++ + 1 file changed, 8 insertions(+) + +diff --git a/io_uring/rw.c b/io_uring/rw.c +index c3c154790e45..ed7f67097572 100644 +--- a/io_uring/rw.c ++++ b/io_uring/rw.c +@@ -825,6 +825,14 @@ static int __io_read(struct io_kiocb *req, unsigned int issue_flags) + + ret = io_iter_do_read(rw, &s->iter); + ++ /* ++ * Some file systems like to return -EOPNOTSUPP for an IOCB_NOWAIT ++ * issue, even though they should be returning -EAGAIN. To be safe, ++ * retry from blocking context for either. ++ */ ++ if (ret == -EOPNOTSUPP && force_nonblock) ++ ret = -EAGAIN; ++ + if (ret == -EAGAIN || (req->flags & REQ_F_REISSUE)) { + req->flags &= ~REQ_F_REISSUE; + /* -- 2.39.5 _______________________________________________ pve-devel mailing list pve-devel@lists.proxmox.com https://lists.proxmox.com/cgi-bin/mailman/listinfo/pve-devel
