Linux block layer
 help / color / mirror / Atom feed
From: Christoph Hellwig <hch@lst.de>
To: Keith Busch <kbusch@meta.com>
Cc: linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org,
	dm-devel@lists.linux.dev, hch@lst.de, axboe@kernel.dk,
	brauner@kernel.org, djwong@kernel.org, viro@zeniv.linux.org.uk,
	Keith Busch <kbusch@kernel.org>,
	stable@vger.kernel.org
Subject: Re: [PATCHv2 6/6] block: validate user space vectors during extraction
Date: Tue, 23 Jun 2026 17:10:21 +0200	[thread overview]
Message-ID: <20260623151021.GA14919@lst.de> (raw)
In-Reply-To: <20260622174241.2299563-7-kbusch@meta.com>

> +#ifdef CONFIG_DEBUG_KERNEL

That's a pretty broad option.  Not that I have any better idea off the
bat.

> +static inline bool bio_iov_bvec_aligned(const struct bio *bio,
> +					unsigned mem_align_mask)
> +{
> +	/*
> +	 * The vectors are owned and laid out by the caller; we only forward
> +	 * them. Most callers are already aligned, but io_uring can place a
> +	 * user chosen offset through a registered buffer, where only the first
> +	 * vector may be unaligned.
> +	 */
> +	return !(mp_bvec_iter_offset(bio->bi_io_vec, bio->bi_iter) &
> +							mem_align_mask);

I don't fully understand the comment.  I guess this is to say ITER_BVEC
users better don't create any alignment gaps?  Maybe we should also
clearly document that in uio.h?

>  	return bio_iov_iter_get_pages(bio, iter,
> +			bdev_dma_alignment(bdev),

Nit: this easily fits onto the previous line.

Otherwise this looks good.

  reply	other threads:[~2026-06-23 15:10 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-06-22 17:42 [PATCHv2 0/6] direct-io: validate user space vectors during extraction Keith Busch
2026-06-22 17:42 ` [PATCHv2 1/6] block: introduce bio_endio_errno helper Keith Busch
2026-06-23 14:54   ` Christoph Hellwig
2026-06-23 15:05     ` Keith Busch
2026-06-23 15:07       ` Christoph Hellwig
2026-06-22 17:42 ` [PATCHv2 2/6] block: report the actual status Keith Busch
2026-06-23 14:55   ` Christoph Hellwig
2026-06-23 14:59     ` Keith Busch
2026-06-22 17:42 ` [PATCHv2 3/6] block: fix dio leak on metadata mapping error Keith Busch
2026-06-23 15:01   ` Christoph Hellwig
2026-06-22 17:42 ` [PATCHv2 4/6] loop: set dma_alignment from the backing file for direct I/O Keith Busch
2026-06-23 15:04   ` Christoph Hellwig
2026-06-22 17:42 ` [PATCHv2 5/6] zloop: set dma_alignment from the backing files " Keith Busch
2026-06-23 15:06   ` Christoph Hellwig
2026-06-22 17:42 ` [PATCHv2 6/6] block: validate user space vectors during extraction Keith Busch
2026-06-23 15:10   ` Christoph Hellwig [this message]
2026-06-23 16:17     ` Keith Busch

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=20260623151021.GA14919@lst.de \
    --to=hch@lst.de \
    --cc=axboe@kernel.dk \
    --cc=brauner@kernel.org \
    --cc=djwong@kernel.org \
    --cc=dm-devel@lists.linux.dev \
    --cc=kbusch@kernel.org \
    --cc=kbusch@meta.com \
    --cc=linux-block@vger.kernel.org \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=stable@vger.kernel.org \
    --cc=viro@zeniv.linux.org.uk \
    /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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox