Ubi patch proposition for 3.10.y

[Richard Genoud]

2014-09-08 12:04 GMT+02:00 Willy Tarreau <w at 1wt.eu>:
> Hi Artem,
>
> On Mon, Sep 08, 2014 at 12:58:38PM +0300, Artem Bityutskiy wrote:
>> On Fri, 2014-08-29 at 14:26 +0200, jean-philippe francois wrote:
>> > Hi,
>> >
>> > I think commit 4b3e0a25... [1] (UBI: Call scan_all() with correct
>> > offset in error case) should be added to 3.10.y stable branch.
>>
>> This is the "fastmap" fix, and fastmap is called experimental. We do not
>> have enough confidence it is production ready. Specifically, I'd like to
>> hear someone doing extensive power-cut testing with this feature. The
>> power-cut tolerance is one of the "selling features" of UBI/UBIFS, after
>> all.
>>
>> Therefore I never added fastmap fixes to the stable queue.
>>
>> But if someone is willing to put all the fastmap fixes together, add the
>> "stable tags" with the right kernel version "markings", and test for few
>> older kernels, then I will recommend them to be included to the stable.
>> Although I am not sure the stable maintainers would like accept them.
>>
>> But I do not recommend adding this single patch to the stable queue.
>>
>> But better, if people started paying more attention to "fastmap", we may
>> agree that from now on we are careful about the sending the fixes to the
>> stable queue.
>
> Personally, I think that whatever feature provided in a kernel release is
> subject to being used and deserves its fixes. There are some cases where
> we *know* that some features are not used (eg: when they don't work without
> a lot of patching or tweaking), but if they seem to work for end users, they
> are likely to be used.
>
> Just my two cents,
> Willy

And fastmap is a really sexy feature...
I couldn't resist adding it to my project.
We are not in production yet, but we will be soon.
For now, I'm letting end users playing with it. That's a good test usually :).

And for the record, I'm stuck with 3.14.18 for now, so I'll welcome
fixes on fastmap.


Richard.