From: Luis Chamberlain <mcgrof@kernel.org>
To: Christoph Hellwig <hch@lst.de>
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>,
Jason Gunthorpe <jgg@nvidia.com>,
"dri-devel@lists.freedesktop.org"
<dri-devel@lists.freedesktop.org>,
Greg KH <gregkh@linuxfoundation.org>,
"intel-gfx@lists.freedesktop.org"
<intel-gfx@lists.freedesktop.org>,
Joonas Lahtinen <joonas.lahtinen@linux.intel.com>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
Jani Nikula <jani.nikula@linux.intel.com>,
Gerd Hoffmann <kraxel@redhat.com>,
"Vivi, Rodrigo" <rodrigo.vivi@intel.com>,
"intel-gvt-dev@lists.freedesktop.org"
<intel-gvt-dev@lists.freedesktop.org>,
"Wang, Zhi A" <zhi.a.wang@intel.com>,
Jani Nikula <jani.nikula@intel.com>
Subject: Re: refactor the i915 GVT support
Date: Fri, 20 Aug 2021 12:56:34 -0700 [thread overview]
Message-ID: <YSAI8pKAvvW/8S2O@bombadil.infradead.org> (raw)
In-Reply-To: <20210820141724.GA29034@lst.de>
On Fri, Aug 20, 2021 at 04:17:24PM +0200, Christoph Hellwig wrote:
> On Thu, Aug 19, 2021 at 04:29:29PM +0800, Zhenyu Wang wrote:
> > I'm working on below patch to resolve this. But I met a weird issue in
> > case when building i915 as module and also kvmgt module, it caused
> > busy wait on request_module("kvmgt") when boot, it doesn't happen if
> > building i915 into kernel. I'm not sure what could be the reason?
>
> Luis, do you know if there is a problem with a request_module from
> a driver ->probe routine that is probably called by a module_init
> function itself?
Generally no, but you can easily foot yourself in the feet by creating
cross dependencies and not dealing with them properly. I'd make sure
to keep module initialization as simple as possible, and run whatever
takes more time asynchronously, then use a state machine to allow
you to verify where you are in the initialization phase or query it
or wait for a completion with a timeout.
It seems the code in question is getting some spring cleaning, and its
unclear where the code is I can inspect. If there's a tree somewhere I
can take a peak I'd be happy to review possible oddities that may stick
out.
My goto model for these sorts of problems is to abstract the issue
*outside* of the driver in question and implement new selftests to
try to reproduce. This serves two purposes, 1) helps with testing
2) may allow you to see the problem more clearly.
Luis
next prev parent reply other threads:[~2021-08-20 19:56 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20210721155355.173183-1-hch@lst.de>
2021-07-22 9:45 ` refactor the i915 GVT support Zhenyu Wang
2021-07-22 10:49 ` Wang, Zhi A
2021-07-22 11:26 ` Gerd Hoffmann
2021-07-27 12:12 ` Jason Gunthorpe
2021-07-28 13:38 ` Wang, Zhi A
2021-07-28 13:43 ` Greg KH
2021-07-28 17:59 ` Jason Gunthorpe
[not found] ` <20210729072022.GB31896@lst.de>
2021-07-29 7:30 ` [Intel-gfx] " Daniel Vetter
2021-08-03 9:43 ` Zhenyu Wang
2021-08-03 14:30 ` Jason Gunthorpe
2021-08-04 5:26 ` Zhenyu Wang
[not found] ` <20210816173458.GA9183@lst.de>
2021-08-17 1:08 ` Zhenyu Wang
2021-08-17 5:22 ` Zhenyu Wang
2021-08-19 8:29 ` Zhenyu Wang
2021-08-19 14:43 ` Joonas Lahtinen
2021-08-26 6:04 ` Zhenyu Wang
[not found] ` <20210820141724.GA29034@lst.de>
2021-08-20 19:56 ` Luis Chamberlain [this message]
2021-08-26 6:12 ` Zhenyu Wang
2021-09-28 7:41 ` Wang, Zhi A
2021-09-28 14:00 ` Luis Chamberlain
2021-09-28 14:35 ` Wang, Zhi A
2021-09-28 15:05 ` Jason Gunthorpe
2021-09-29 18:27 ` Wang, Zhi A
2021-09-29 18:55 ` Jason Gunthorpe
2021-10-01 13:01 ` Wang, Zhi A
2021-10-05 7:33 ` Wang, Zhi A
2021-08-26 6:08 ` Zhenyu Wang
2021-07-29 8:19 ` Wang, Zhi A
2021-07-22 13:16 ` Greg KH
[not found] ` <20210721155355.173183-2-hch@lst.de>
2021-08-03 9:27 ` [PATCH 01/21] drm/i915/gvt: integrate into the main Makefile Zhenyu Wang
[not found] ` <20210721155355.173183-5-hch@lst.de>
2021-08-09 11:29 ` [PATCH 04/21] drm/i915/gvt: move the gvt code into kvmgt.ko Joonas Lahtinen
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=YSAI8pKAvvW/8S2O@bombadil.infradead.org \
--to=mcgrof@kernel.org \
--cc=dri-devel@lists.freedesktop.org \
--cc=gregkh@linuxfoundation.org \
--cc=hch@lst.de \
--cc=intel-gfx@lists.freedesktop.org \
--cc=intel-gvt-dev@lists.freedesktop.org \
--cc=jani.nikula@intel.com \
--cc=jani.nikula@linux.intel.com \
--cc=jgg@nvidia.com \
--cc=joonas.lahtinen@linux.intel.com \
--cc=kraxel@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=rodrigo.vivi@intel.com \
--cc=zhenyuw@linux.intel.com \
--cc=zhi.a.wang@intel.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).