From: Steven Price <steven.price@arm.com>
To: dri-devel@lists.freedesktop.org,
Alyssa Rosenzweig <alyssa@collabora.com>
Cc: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>,
Rob Herring <robh@kernel.org>,
Tomeu Vizoso <tomeu.vizoso@collabora.com>,
David Airlie <airlied@linux.ie>, Daniel Vetter <daniel@ffwll.ch>,
linux-kernel@vger.kernel.org,
Chris Morgan <macromorgan@hotmail.com>
Subject: Re: [PATCH 2/3] drm/panfrost: Use u64 for size in lock_region
Date: Mon, 23 Aug 2021 22:57:56 +0100 [thread overview]
Message-ID: <77CFD756-7F02-4CBA-9E58-3EDA2167620E@arm.com> (raw)
In-Reply-To: <YSQO7exgqnk0ZLJT@maud>
On 23 August 2021 22:11:09 BST, Alyssa Rosenzweig <alyssa@collabora.com> wrote:
>> > Mali virtual addresses are 48-bit. Use a u64 instead of size_t to ensure
>> > we can express the "lock everything" condition as ~0ULL without relying
>> > on platform-specific behaviour.
>>
>> 'platform-specific behaviour' makes it sound like this is something to
>> do with a particular board. This is 32bit/64bit - it's going to be
>> broken on 32bit: large lock regions are not going to work.
>
>Oh, my. I used the term as a weasel word since the spec is loose on how
>big a size_t actually is. But if this is causing actual breakage on
>armv7 we're in trouble. I'll add a Cc stable tag on v2, unless the Fixes
>implies that?
The usual practice is to put CC: stable in the commit message or the fixes tag (no need to actually CC the stable email address). So just Fixes: should work
>Thanks for pointing this out.
It's not actually quite so bad as it could be as >4GB regions are unlikely (especially on 32bit), but the GPU does of course support such a thing.
Thanks,
Steve
next prev parent reply other threads:[~2021-08-23 21:58 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-08-20 21:31 [PATCH 0/3] drm/panfrost: Bug fixes for lock_region Alyssa Rosenzweig
2021-08-20 21:31 ` [PATCH 1/3] drm/panfrost: Simplify lock_region calculation Alyssa Rosenzweig
2021-08-23 9:40 ` Steven Price
2021-08-23 9:40 ` Steven Price
2021-08-23 21:09 ` Alyssa Rosenzweig
2021-08-23 21:54 ` Steven Price
2021-08-20 21:31 ` [PATCH 2/3] drm/panfrost: Use u64 for size in lock_region Alyssa Rosenzweig
2021-08-23 9:40 ` Steven Price
2021-08-23 9:40 ` Steven Price
2021-08-23 21:11 ` Alyssa Rosenzweig
2021-08-23 21:57 ` Steven Price [this message]
2021-08-20 21:31 ` [PATCH 3/3] drm/panfrost: Clamp lock region to Bifrost minimum Alyssa Rosenzweig
2021-08-23 9:40 ` Steven Price
2021-08-23 9:40 ` Steven Price
2021-08-23 21:13 ` Alyssa Rosenzweig
2021-08-23 22:02 ` Steven Price
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=77CFD756-7F02-4CBA-9E58-3EDA2167620E@arm.com \
--to=steven.price@arm.com \
--cc=airlied@linux.ie \
--cc=alyssa.rosenzweig@collabora.com \
--cc=alyssa@collabora.com \
--cc=daniel@ffwll.ch \
--cc=dri-devel@lists.freedesktop.org \
--cc=linux-kernel@vger.kernel.org \
--cc=macromorgan@hotmail.com \
--cc=robh@kernel.org \
--cc=tomeu.vizoso@collabora.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.