Re: Please help cherry pick four mmc related changes into the 4.14 stable kernel

From: Greg KH <gregkh@linuxfoundation.org>
To: Yongqin Liu <yongqin.liu@linaro.org>
Cc: stable@vger.kernel.org,
	"Naresh Kamboju" <naresh.kamboju@linaro.org>,
	"Benjamin Copeland" <benjamin.copeland@linaro.org>,
	"Sumit Semwal" <sumit.semwal@linaro.org>,
	"Daniel Díaz" <daniel.diaz@linaro.org>,
	"Alistair Delva" <adelva@google.com>,
	"Steve Muckle" <smuckle@google.com>,
	"Todd Kjos" <tkjos@google.com>,
	"Bajjuri, Praneeth" <praneeth@ti.com>,
	"Vincent Guittot" <vincent.guittot@linaro.org>,
	"Anders Roxell" <anders.roxell@linaro.org>,
	linux-mmc@vger.kernel.org, linux-block@vger.kernel.org,
	"Ulf Hansson" <ulf.hansson@linaro.org>
Subject: Re: Please help cherry pick four mmc related changes into the 4.14 stable kernel
Date: Mon, 13 Jun 2022 20:11:18 +0200	[thread overview]
Message-ID: <Yqd9xjOiOapfBt/A@kroah.com> (raw)
In-Reply-To: <CAMSo37WW9veYH6=tHqUR2pa_7YX1UuzHqLBHit60P2QyzQmCEw@mail.gmail.com>

On Wed, Jun 08, 2022 at 01:09:54AM +0800, Yongqin Liu wrote:
> Hi, All
> 
> With the 4.14.281 version[1], there were three mmc related changes merged,
> but that causes one boot failure with the X15 Android builds, a problem
> similar to one reported before here[2].
> After being confirmed with Ulf Hansson, and verified with the X15 Android build,
> it needs to have the following four commits cherry-picked to the 4.14
> branch as well.
> 
>     4f32b45c9a2c mmc: core: Allow host controllers to require R1B for CMD6
>     5fc615c1e3eb mmc: core: Respect MMC_CAP_NEED_RSP_BUSY for erase/trim/discard
>     d091259b8d7a mmc: core: Respect MMC_CAP_NEED_RSP_BUSY for eMMC sleep command
>     23161bed631a mmc: sdhci-omap: Fix busy detection by enabling
> MMC_CAP_NEED_RSP_BUSY
> 
> The above four commits are from the 4.19 branch, as they are a little
> easier to be cherry-picked
> into the 4.14 branch, compared to the commits from the mainline branch.
> (I have confirmed that the four commits are all in 4.19, 5.4, 5.10 and
> mainline branches already).
> 
> Saying that, there will be still one merge conflict reported when
> cherry picking the commit of
> 4f32b45c9a2c, it's easy to resolve though.
> To avoid the merge conflict, it could be done like this as well:
> 1. revert the 327b6689898b commit from 4.14 first, so that the commits in step#2
>     could be cherry-picked without any problem
>         327b6689898b mmc: core: Default to generic_cmd6_time as
> timeout in __mmc_switch()
> 2. git cherry-pick the following commits from 4.19 into the 4.14 branch
>         4f32b45c9a2c mmc: core: Allow host controllers to require R1B for CMD6
>         5fc615c1e3eb mmc: core: Respect MMC_CAP_NEED_RSP_BUSY for
> erase/trim/discard
>         d091259b8d7a mmc: core: Respect MMC_CAP_NEED_RSP_BUSY for eMMC
> sleep command
>         23161bed631a mmc: sdhci-omap: Fix busy detection by enabling
> MMC_CAP_NEED_RSP_BUSY
>         26c6f614cf02 mmc: mmc: core: Default to generic_cmd6_time as
> timeout in __mmc_switch()
>     The last commit of 26c6f614cf02 is for the revert in step#1.
> 
> I am not sure which way is more convenient for the maintenance work
> here, so just list both of them here
> for your information.
> And please let me know if there is anything else I could help on this
> cherry pick work here.

Please send properly backported patches to us, trying to do the revert
and fixup like you describe above is going to be hard to verify I got it
right.  A series of patches is best as that way we know you tested it
properly and sent us the correct patches.

thanks,

greg k-h