All of lore.kernel.org
 help / color / mirror / Atom feed
From: Eric Biggers <ebiggers@kernel.org>
To: Stefan Hajnoczi <stefanha@redhat.com>
Cc: qemu-devel@nongnu.org, hreitz@redhat.com, qemu-block@nongnu.org,
	Kevin Wolf <kwolf@redhat.com>,
	nsoffer@redhat.com
Subject: Re: [PATCH 1/2] file-posix: fix Linux alignment probing when EIO is returned
Date: Tue, 1 Nov 2022 19:27:14 -0700	[thread overview]
Message-ID: <Y2HVgnwAPdTIaZR6@sol.localdomain> (raw)
In-Reply-To: <20221101190031.6766-2-stefanha@redhat.com>

On Tue, Nov 01, 2022 at 03:00:30PM -0400, Stefan Hajnoczi wrote:
> Linux dm-crypt returns errno EIO from unaligned O_DIRECT pread(2) calls.

Citation needed.  For direct I/O to block devices, the kernel's block layer
checks the alignment before the I/O is actually submitted to the underlying
block device.  See
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/block/fops.c?h=v6.1-rc3#n306

> Buglink: https://gitlab.com/qemu-project/qemu/-/issues/1290

That "bug" seems to be based on a misunderstanding of the kernel source code,
and not any actual testing.

I just tested it, and the error code is EINVAL.

- Eric


  reply	other threads:[~2022-11-02  2:27 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-11-01 19:00 [PATCH 0/2] file-posix: alignment probing improvements Stefan Hajnoczi
2022-11-01 19:00 ` [PATCH 1/2] file-posix: fix Linux alignment probing when EIO is returned Stefan Hajnoczi
2022-11-02  2:27   ` Eric Biggers [this message]
2022-11-02  2:49     ` Eric Biggers
2022-11-02 18:50       ` Stefan Hajnoczi
2022-11-03  9:52       ` Kevin Wolf
2022-11-03 13:57         ` Stefan Hajnoczi
2022-11-03 16:26         ` Eric Biggers
2022-11-03 16:54           ` Eric Biggers
2022-11-03 17:54             ` Stefan Hajnoczi
2022-11-01 19:00 ` [PATCH 2/2] file-posix: add statx(STATX_DIOALIGN) support Stefan Hajnoczi
2022-11-02  3:32   ` Eric Biggers
2022-11-02 18:53     ` Stefan Hajnoczi

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=Y2HVgnwAPdTIaZR6@sol.localdomain \
    --to=ebiggers@kernel.org \
    --cc=hreitz@redhat.com \
    --cc=kwolf@redhat.com \
    --cc=nsoffer@redhat.com \
    --cc=qemu-block@nongnu.org \
    --cc=qemu-devel@nongnu.org \
    --cc=stefanha@redhat.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.