From: Eric Biggers <ebiggers@kernel.org>
To: Mike Snitzer <snitzer@redhat.com>
Cc: Damien.LeMoal@wdc.com, ssudhakarp@gmail.com,
Martin Petersen <martin.petersen@oracle.com>,
dm-crypt@saout.de,
Sudhakar Panneerselvam <sudhakar.panneerselvam@oracle.com>,
dm-devel@redhat.com, Shirley Ma <shirley.ma@oracle.com>,
mpatocka@redhat.com, Milan Broz <gmazyland@gmail.com>,
agk@redhat.com
Subject: Re: [RFC PATCH 0/2] dm crypt: Allow unaligned buffer lengths for skcipher devices
Date: Wed, 23 Sep 2020 22:14:19 -0700 [thread overview]
Message-ID: <20200924051419.GA16103@sol.localdomain> (raw)
In-Reply-To: <20200924012732.GA10766@redhat.com>
On Wed, Sep 23, 2020 at 09:27:32PM -0400, Mike Snitzer wrote:
> You've clearly done a nice job with these changes. Looks clean.
>
> BUT, I'm struggling to just accept that dm-crypt needs to go to these
> extra lengths purely because of one bad apple usecase.
>
> These alignment constraints aren't new. Are there other portions of
> Linux's crypto subsystem that needed comparable fixes in order to work
> with Microsfot OS initiated IO through a guest?
>
> You forecast that these same kinds of changes are needed for AEAD and
> dm-integrity... that's alarming.
>
> Are we _certain_ there is no other way forward?
> (Sorry I don't have suggestions.. I'm in "fact finding mode" ;)
>
I don't understand why this is needed, since dm-crypt already sets its
logical_block_size to its crypto sector_size. Isn't it expected that I/O that
isn't aligned to logical_block_size fails? It's the I/O submitter's
responsibility to ensure logical_block_size alignment of all I/O segments.
Exactly how is the misaligned I/O actually being submitted here?
- Eric
next prev parent reply other threads:[~2020-09-24 5:14 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-09-16 18:40 [RFC PATCH 0/2] dm crypt: Allow unaligned buffer lengths for skcipher devices Sudhakar Panneerselvam
2020-09-16 18:40 ` [RFC PATCH 1/2] dm crypt: Allow unaligned bio " Sudhakar Panneerselvam
2020-09-16 18:40 ` [RFC PATCH 2/2] dm crypt: Handle unaligned bio buffer lengths for lmk and tcw Sudhakar Panneerselvam
2020-09-23 17:01 ` [RFC PATCH 0/2] dm crypt: Allow unaligned buffer lengths for skcipher devices Sudhakar Panneerselvam
2020-09-24 1:27 ` Mike Snitzer
2020-09-24 5:14 ` Eric Biggers [this message]
2020-09-24 8:15 ` Milan Broz
2020-09-24 16:55 ` Sudhakar Panneerselvam
2020-09-24 16:44 ` Sudhakar Panneerselvam
2020-09-24 17:26 ` Mikulas Patocka
2020-09-24 17:38 ` Sudhakar Panneerselvam
2020-09-24 17:50 ` Mikulas Patocka
2020-09-24 18:11 ` Sudhakar Panneerselvam
2020-09-24 18:44 ` Mikulas Patocka
2020-09-24 19:13 ` Sudhakar Panneerselvam
2020-09-25 1:09 ` Damien Le Moal
2020-09-25 20:15 ` Mike Snitzer
2020-09-24 12:47 ` Mikulas Patocka
2020-09-24 15:58 ` Sudhakar Panneerselvam
2020-09-24 12:40 ` Mikulas Patocka
2020-09-24 17:12 ` Sudhakar Panneerselvam
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=20200924051419.GA16103@sol.localdomain \
--to=ebiggers@kernel.org \
--cc=Damien.LeMoal@wdc.com \
--cc=agk@redhat.com \
--cc=dm-crypt@saout.de \
--cc=dm-devel@redhat.com \
--cc=gmazyland@gmail.com \
--cc=martin.petersen@oracle.com \
--cc=mpatocka@redhat.com \
--cc=shirley.ma@oracle.com \
--cc=snitzer@redhat.com \
--cc=ssudhakarp@gmail.com \
--cc=sudhakar.panneerselvam@oracle.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).