From: Jon Hunter <jonathanh@nvidia.com>
To: Joakim Zhang <qiangqing.zhang@nxp.com>,
Giuseppe Cavallaro <peppe.cavallaro@st.com>,
Alexandre Torgue <alexandre.torgue@st.com>,
Jose Abreu <joabreu@synopsys.com>
Cc: "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
linux-tegra <linux-tegra@vger.kernel.org>,
Jakub Kicinski <kuba@kernel.org>
Subject: Re: Regression v5.12-rc3: net: stmmac: re-init rx buffers when mac resume back
Date: Thu, 1 Apr 2021 17:28:33 +0100 [thread overview]
Message-ID: <563db756-ebef-6c8b-ce7c-9dcadaecfea1@nvidia.com> (raw)
In-Reply-To: <DB8PR04MB6795ECCB5E6E2091A45DADAEE67C9@DB8PR04MB6795.eurprd04.prod.outlook.com>
On 31/03/2021 12:41, Joakim Zhang wrote:
...
>> In answer to your question, resuming from suspend does work on this board
>> without your change. We have been testing suspend/resume now on this board
>> since Linux v5.8 and so we have the ability to bisect such regressions. So it is
>> clear to me that this is the change that caused this, but I am not sure why.
>
> Yes, I know this issue is regression caused by my patch. I just want to analyze the potential reasons. Due to the code change only related to the page recycle and reallocate.
> So I guess if this page operate need IOMMU works when IOMMU is enabled. Could you help check if IOMMU driver resume before STMMAC? Our common desire is to find the root cause, right?
Yes of course that is the desire here indeed. I had assumed that the
suspend/resume order was good because we have never seen any problems,
but nonetheless it is always good to check. Using ftrace I enabled
tracing of the appropriate suspend/resume functions and this is what
I see ...
# tracer: function
#
# entries-in-buffer/entries-written: 4/4 #P:6
#
# _-----=> irqs-off
# / _----=> need-resched
# | / _---=> hardirq/softirq
# || / _--=> preempt-depth
# ||| / delay
# TASK-PID CPU# |||| TIMESTAMP FUNCTION
# | | | |||| | |
rtcwake-748 [000] ...1 536.700777: stmmac_pltfr_suspend <-platform_pm_suspend
rtcwake-748 [000] ...1 536.735532: arm_smmu_pm_suspend <-platform_pm_suspend
rtcwake-748 [000] ...1 536.757290: arm_smmu_pm_resume <-platform_pm_resume
rtcwake-748 [003] ...1 536.856771: stmmac_pltfr_resume <-platform_pm_resume
So I don't see any ordering issues that could be causing this.
Jon
--
nvpublic
next prev parent reply other threads:[~2021-04-01 17:56 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-03-24 10:50 Regression v5.12-rc3: net: stmmac: re-init rx buffers when mac resume back Jon Hunter
2021-03-24 12:20 ` Joakim Zhang
2021-03-24 12:39 ` Jon Hunter
2021-03-25 7:53 ` Joakim Zhang
2021-03-25 8:00 ` Jon Hunter
2021-03-25 8:12 ` Joakim Zhang
2021-03-30 12:50 ` Jon Hunter
2021-03-31 7:43 ` Joakim Zhang
2021-03-31 11:10 ` Joakim Zhang
2021-03-31 11:29 ` Jon Hunter
2021-03-31 11:41 ` Joakim Zhang
2021-04-01 16:28 ` Jon Hunter [this message]
2021-04-13 8:41 ` Jon Hunter
2021-04-13 12:13 ` Joakim Zhang
2021-04-13 16:06 ` Thierry Reding
2021-04-13 16:43 ` Jakub Kicinski
2021-04-14 2:18 ` Joakim Zhang
2021-04-14 7:40 ` Thierry Reding
2021-04-14 8:06 ` Joakim Zhang
2021-04-14 12:22 ` Joakim Zhang
2021-03-31 11:11 ` Jon Hunter
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=563db756-ebef-6c8b-ce7c-9dcadaecfea1@nvidia.com \
--to=jonathanh@nvidia.com \
--cc=alexandre.torgue@st.com \
--cc=joabreu@synopsys.com \
--cc=kuba@kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-tegra@vger.kernel.org \
--cc=netdev@vger.kernel.org \
--cc=peppe.cavallaro@st.com \
--cc=qiangqing.zhang@nxp.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).