Re: [PATCH 3.10] pstore: Make spinlock per zone instead of global

[Willy Tarreau <w@1wt.eu>]

On Fri, Jul 28, 2017 at 02:52:15PM +0800, Leo Yan wrote:
> On Fri, Jul 28, 2017 at 06:25:55AM +0200, Willy Tarreau wrote:
> > Hi Leo,
> > 
> > There was no upstream commit ID here but I found it in mainline here :
> > 
> >   commit 109704492ef637956265ec2eb72ae7b3b39eb6f4
> >   Author: Joel Fernandes <joelaf@google.com>
> >   Date:   Thu Oct 20 00:34:00 2016 -0700
> > 
> >     pstore: Make spinlock per zone instead of global
> >     
> > What worries me is that some later fixes were issued, apparently to fix
> > an oops and a warning after this patch :
> 
> Yes, below two patches I also notices. But at least I have not
> reproduce them on Android common kernel 4.4. I only faced the hang
> issue and the first patch just fixes it.

OK but maybe by breaking something else that the other ones have to
fix. That's my main concern in fact.

> BTW, I tried to port the second and third patch, but seems the
> second patch is dependency on one extra patch; so avoid to introduce
> complexity to resolve issue, I just port the first one for fixing
> issues.

OK.

> > Also, the information you added to the commit message references a trace
> > on a 4.4 kernel. Do you confirm that you got the same issue on 3.10 ?
> 
> No, I only can confirm this on kernel 4.4. Now only kernel 4.4 are
> avaliable on the board, and I verified mainline kernel can work well;
> so this is why I can check difference between them and find the first
> patch is critical.

Given that 3.10 only has a few months left, if 3.10 isn't available on
this hardware, do you really think we need to fix something in it that
apparently nobody will be in situation to experience, at the risk of
possibly adding some partial breakage ?

I'm not opposed, really just asking.

Thanks,
Willy