From: Tejun Heo <tj@kernel.org>
To: Andrea Righi <arighi@nvidia.com>
Cc: sched-ext@lists.linux.dev, David Vernet <void@manifault.com>,
Changwoo Min <changwoo@igalia.com>,
Emil Tsalapatis <emil@etsalapatis.com>,
David Dai <david.dai@linux.dev>,
linux-kernel@vger.kernel.org
Subject: Re: [PATCHSET sched_ext/for-7.3-fixes] sched_ext: Fix bypass leaving the running task protected and bypassed tasks stranded
Date: Sat, 17 Oct 2026 05:34:51 -1000 [thread overview]
Message-ID: <5df189160a62dada9a26b92404addce8@kernel.org> (raw)
In-Reply-To: <atNKHI9K-_Rbh9Og@gpd4>
Hello, Andrea.
On Sat, Oct 17, 2026 at 12:12:44PM +0200, Andrea Righi wrote:
> - when merging for-7.3-fixes into for-7.4, with proxy exec the slice and the
> protection belong to the donor, so I think the resolution should use rq->donor
> instead of rq->curr, both for the strip on bypass and for the eviction on
> unbypass. With rq->curr, a blocked SCX donor would keep its protection into
> bypass and we'd act on the proxy owner instead.
Yes, the merge into for-7.4 will use rq->donor for both.
> - not a regression and probably transient (I haven't verified it):
> bypass_lb_cpu() doesn't look at caps, when the nearest non-bypassing ancestor
> running a bypassed sched's tasks is itself a sub-sched with caps only on some
> CPUs, could a bypassed task still be moved to a CPU it can't stay on, until
> bypass lifts?
Yeah, that's already being worked on in a separate series.
Thanks.
--
tejun
next prev parent reply other threads:[~2026-10-17 15:34 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-10-17 5:37 [PATCHSET sched_ext/for-7.3-fixes] sched_ext: Fix bypass leaving the running task protected and bypassed tasks stranded Tejun Heo
2026-10-17 5:37 ` [PATCH 1/2] sched_ext: Fix the running task keeping its protection into bypass Tejun Heo
2026-10-17 5:37 ` [PATCH 2/2] sched_ext: Fix a bypassed task stalling on a cpu its scheduler has no caps on Tejun Heo
2026-10-17 10:12 ` [PATCHSET sched_ext/for-7.3-fixes] sched_ext: Fix bypass leaving the running task protected and bypassed tasks stranded Andrea Righi
2026-10-17 15:34 ` Tejun Heo [this message]
2026-10-17 15:34 ` Tejun Heo
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=5df189160a62dada9a26b92404addce8@kernel.org \
--to=tj@kernel.org \
--cc=arighi@nvidia.com \
--cc=changwoo@igalia.com \
--cc=david.dai@linux.dev \
--cc=emil@etsalapatis.com \
--cc=linux-kernel@vger.kernel.org \
--cc=sched-ext@lists.linux.dev \
--cc=void@manifault.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.