Re: [RFC v4 0/3] pstore/rom: new support logger for block devices

From: ååé
Date: Fri Jan 04 2019 - 02:03:44 EST


hi Tony:
On 2019-01-04 01:18, Luck, Tony wrote:
> I'm curious why you call this "pstore/rom" rather than the more descriptive "pstore/block".
Because there is "pstore/ram", so i name it as "pstore/rom".
It's nice to rename it "pstore/block", i will change it in next version
of patch.
>
> It looks to be a really good idea.
Should i add "Acked-by" in next version of patch?
I have little experience in sending patch to upstream linux.
>
> I think you need to document how the "write" function for the block device must be written.
> Since pstore calls this at "panic" time, the write path:
>
> + Cannot allocate any memory
> + Must be polled, not interrupt driven
> + Cannot take any locks that may be held by regular code
> + ... perhaps other restrictions that I can't think of right now
>
> The memory allocation restriction is likely easy to get around. Just allocate anything
> you need at pstore "init" time rather than waiting until the panic.
>I will provide a documemt for it in next version of patch.
> -Tony
>