From: Kevin Wolf <kwolf@redhat.com>
To: lishan <lishan24@huawei.com>
Cc: hreitz@redhat.com, qemu-devel@nongnu.org, qemu-block@nongnu.org,
eric.fangyi@huawei.com
Subject: Re: [PATCH] block/file-posix: Limit max_iov to IOV_MAX
Date: Mon, 20 Sep 2021 10:14:26 +0200 [thread overview]
Message-ID: <YUhC4pvNdlmnMzsh@redhat.com> (raw)
In-Reply-To: <20210918073300.30224-1-lishan24@huawei.com>
Am 18.09.2021 um 09:33 hat lishan geschrieben:
> AIO read/write. The size of iocb->aio_nbytes in the kernel cannot exceed UIO_MAXIOV = 1024.
> max_segments read from the block device layer may be greater than UIO_MAXIOV,
> this causes the ioq_submit interface to return a -22(-EINVAL) error result.
You need a Signed-off-by line so that a patch can be accepted.
But Paolo intended to send a better solution anyway (splitting max_iov
into two separate limits). Not sure what the status is there.
Kevin
> block/file-posix.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/block/file-posix.c b/block/file-posix.c
> index d81e15efa4..27ab8d8784 100644
> --- a/block/file-posix.c
> +++ b/block/file-posix.c
> @@ -1273,7 +1273,8 @@ static void raw_refresh_limits(BlockDriverState *bs, Error **errp)
>
> ret = hdev_get_max_segments(s->fd, &st);
> if (ret > 0) {
> - bs->bl.max_iov = ret;
> + /* The maximum segment size allowed by the kernel is UIO_MAXIOV = 1024. */
> + bs->bl.max_iov = MIN(ret, bs->bl.max_iov);
> }
> }
> }
> --
> 2.19.1.windows.1
>
>
next prev parent reply other threads:[~2021-09-20 8:23 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-09-18 7:33 [PATCH] block/file-posix: Limit max_iov to IOV_MAX lishan
2021-09-20 8:14 ` Kevin Wolf [this message]
-- strict thread matches above, loose matches on Subject: below --
2021-09-18 4:06 lishan
2021-09-20 4:47 ` Markus Armbruster
2021-09-20 9:03 ` Daniel P. Berrangé
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=YUhC4pvNdlmnMzsh@redhat.com \
--to=kwolf@redhat.com \
--cc=eric.fangyi@huawei.com \
--cc=hreitz@redhat.com \
--cc=lishan24@huawei.com \
--cc=qemu-block@nongnu.org \
--cc=qemu-devel@nongnu.org \
/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.