Subject: Re: next-20160401+: ARM: DRA7: linux-next regression: mm/slab: clean-up kmem_cache_node setup

From: Joonsoo Kim <[email-masked]>
Date: Wed, 20 Apr 2016 16:49:00 +0900

Ccing Stephen.

On Wed, Apr 20, 2016 at 08:11:41AM +0100, Jon Hunter wrote:
> Hi Joonsoo,
> 
> On 11/04/16 12:44, Jon Hunter wrote:
> > On 11/04/16 03:02, Joonsoo Kim wrote:
> >> On Fri, Apr 08, 2016 at 03:39:20PM -0500, Nishanth Menon wrote:
> >>> Hi,
> >>>
> >>> http://marc.info/?l=linux-omap&m=146014314115625&w=2 series works with
> >>> v4.6-rc2 kernel, however, it fails with linux-next for suspend-to-ram
> >>> (mem) on BeagleBoard-X15
> >>>
> >>> next-20160327 - good
> >>> next-20160329 - good
> >>> next-20160330 - Fails to boot - I2C crashes
> >>> next-20160331-  Fails to boot - USB crashes
> >>> next-20160401 -> bad
> >>> next-20160408 -> bad
> >>>
> >>> Bisect log of next-20160408 vs v4.6-rc2 ->
> >>> http://pastebin.ubuntu.com/15697856/
> >>>
> >>> # first bad commit: [2b629704a2b6a5b239f23750e5517a9d8c3a4e8c]
> >>> mm/slab: clean-up kmem_cache_node setup
> >>>
> >>
> >> Hello,
> >>
> >> I made a mistake on that patch. Could you try to test below one on
> >> top of it.
> >>
> >> Thanks.
> >>
> >> --------->8----------------
> >> From d3af3cc409527e9be6beb62ea395cde67f3c5029 Mon Sep 17 00:00:00 2001
> >> From: Joonsoo Kim <[email-masked]>
> >> Date: Mon, 11 Apr 2016 10:48:29 +0900
> >> Subject: [PATCH] mm/slab: clean-up kmem_cache_node setup-fix
> >>
> >> After calling free_block(), we need to re-calculate array_cache's
> >> avail counter. Fix it.
> >>
> >> And, it's better to free objects in shared array when it is
> >> really necessary. Check it before calling free_block().
> >>
> >> Signed-off-by: Joonsoo Kim <[email-masked]>
> >> ---
> >>  mm/slab.c | 3 ++-
> >>  1 file changed, 2 insertions(+), 1 deletion(-)
> >>
> >> diff --git a/mm/slab.c b/mm/slab.c
> >> index fcd5fbb..27cb390 100644
> >> --- a/mm/slab.c
> >> +++ b/mm/slab.c
> >> @@ -927,9 +927,10 @@ static int setup_kmem_cache_node(struct kmem_cache *cachep,
> >>  
> >>  	n = get_node(cachep, node);
> >>  	spin_lock_irq(&n->list_lock);
> >> -	if (n->shared) {
> >> +	if (n->shared && force_change) {
> >>  		free_block(cachep, n->shared->entry,
> >>  				n->shared->avail, node, &list);
> >> +		n->shared->avail = 0;
> >>  	}
> >>  
> >>  	if (!n->shared || force_change) {
> > 
> > This also fixes a regression on -next for Tegra that was bisected down
> > to the same culprit. So ...
> > 
> > Tested-by: Jon Hunter <[email-masked]>
> 
> This fix still doesn't appear to have made it into -next and this has
> been broken now for nearly 3 weeks. Any chance we can get this into -next?

Sorry about that.

Hello, Stephen.

It seems that Andrew is busy now. I guess he will be back soon but
could you merge this fix to the next tree directly?

Thanks.