Message-ID: <2a181fd4-9248-d68d-7eee-43b19db96461@leemhuis.info>
Date:   Mon, 6 Dec 2021 18:39:19 +0100
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Subject: Re: [PATCH] bus: mhi: core: Add support for forced PM resume
Content-Language: en-BS
To:     Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>,
        mhi@lists.linux.dev
Cc:     hemantk@codeaurora.org, bbhatt@codeaurora.org,
        loic.poulain@linaro.org, linux-arm-msm@vger.kernel.org,
        linux-kernel@vger.kernel.org, ath11k@lists.infradead.org,
        linux-wireless@vger.kernel.org, kvalo@codeaurora.org,
        stable@vger.kernel.org, Pengyu Ma <mapengyu@gmail.com>
References: <20211206161059.107007-1-manivannan.sadhasivam@linaro.org>
From:   Thorsten Leemhuis <regressions@leemhuis.info>
In-Reply-To: <20211206161059.107007-1-manivannan.sadhasivam@linaro.org>
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Hi, this is your Linux kernel regression tracker speaking.

On 06.12.21 17:10, Manivannan Sadhasivam wrote:
> From: Loic Poulain <loic.poulain@linaro.org>
> 
> For whatever reason, some devices like QCA6390, WCN6855 using ath11k
> are not in M3 state during PM resume, but still functional. The
> mhi_pm_resume should then not fail in those cases, and let the higher
> level device specific stack continue resuming process.
> 
> Add a new parameter to mhi_pm_resume, to force resuming, whatever the
> current MHI state is. This fixes a regression with non functional
> ath11k WiFi after suspend/resume cycle on some machines.
> 
> Bug report: https://bugzilla.kernel.org/show_bug.cgi?id=214179
> 
> Cc: stable@vger.kernel.org #5.13
> Fixes: 020d3b26c07a ("bus: mhi: Early MHI resume failure in non M3 state")
> Reported-by: Kalle Valo <kvalo@codeaurora.org>
> Reported-by: Pengyu Ma <mapengyu@gmail.com>

FWIW: In case you need to send an improved patch, could you please add
this before the 'Reported-by:' (see (¹) below for the reasoning):

Link: https://lore.kernel.org/regressions/871r5p0x2u.fsf@codeaurora.org/

And if the patch is already good to go: could the subsystem maintainer
please add it when applying? See(¹) for the reasoning.

Thx.

Ciao, Thorsten, your Linux kernel regression tracker.

(¹) Long story: The commit message would benefit from a link to the
regression report on the mailing list, for reasons explained in
Documentation/process/submitting-patches.rst. To quote:

```
If related discussions or any other background information behind the
change can be found on the web, add 'Link:' tags pointing to it. In case
your patch fixes a bug, for example, add a tag with a URL referencing
the report in the mailing list archives or a bug tracker;
```

This concept is old, but the text was reworked recently to make this use
case for the Link: tag clearer. For details see:
https://git.kernel.org/linus/1f57bd42b77c

Yes, that "Link:" is not really crucial; but it's good to have if
someone needs to look into the backstory of this change sometime in the
future. But I care for a different reason. I'm tracking this regression
(and others) with regzbot, my Linux kernel regression tracking bot. This
bot will notice if a patch with a Link: tag to a tracked regression gets
posted and record that, which allowed anyone looking into the regression
to quickly gasp the current status from regzbot's webui
(https://linux-regtracking.leemhuis.info/regzbot ) or its reports. The
bot will also notice if a commit with a Link: tag to a regression report
is applied by Linus and then automatically mark the regression as
resolved then.

IOW: this tag makes my life a regression tracker a lot easier, as I
otherwise have to tell regzbot manually when the fix lands. :-/

P.S.: As a Linux kernel regression tracker I'm getting a lot of reports
on my table. I can only look briefly into most of them. Unfortunately
therefore I sometimes will get things wrong or miss something important.
I hope that's not the case here; if you think it is, don't hesitate to
tell me about it in a public reply. That's in everyone's interest, as
what I wrote above might be misleading to everyone reading this; any
suggestion I gave they thus might sent someone reading this down the
wrong rabbit hole, which none of us wants.

BTW, I have no personal interest in this issue, which is tracked using
regzbot, my Linux kernel regression tracking bot
(https://linux-regtracking.leemhuis.info/regzbot/). I'm only posting
this mail to get things rolling again and hence don't need to be CC on
all further activities wrt to this regression.

#regzbot ^backmonitor:
https://lore.kernel.org/regressions/871r5p0x2u.fsf@codeaurora.org/