From mboxrd@z Thu Jan  1 00:00:00 1970
From: Walter Wu <walter-zh.wu@mediatek.com>
Subject: Re: [PATCH v2 0/2] mm/kasan: dump alloc/free stack for page
 allocator
Date: Tue, 10 Sep 2019 20:45:49 +0800
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To: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>, Alexander Potapenko <glider@google.com>, Dmitry Vyukov <dvyukov@google.com>, Matthias Brugger <matthias.bgg@gmail.com>, Andrew Morton <akpm@linux-foundation.org>, Martin Schwidefsky <schwidefsky@de.ibm.com>, Will Deacon <will@kernel.org>, Andrey Konovalov <andreyknvl@google.com>, Arnd Bergmann <arnd@arndb.de>, Thomas Gleixner <tglx@linutronix.de>, Michal Hocko <mhocko@kernel.org>, Qian Cai <cai@lca.pw>, linux-kernel@vger.kernel.org, kasan-dev@googlegroups.com, linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, wsd_upstream@mediatek.com
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On Tue, 2019-09-10 at 13:53 +0200, Vlastimil Babka wrote:
> On 9/10/19 12:50 PM, Andrey Ryabinin wrote:
> > 
> > 
> > For slab objects we memorize both alloc and free stacks. You'll never know in advance what information will be usefull
> > to fix an issue, so it usually better to provide more information. I don't think we should do anything different for pages.
> 
> Exactly, thanks.
> 
> > Given that we already have the page_owner responsible for providing alloc/free stacks for pages, all that we should in KASAN do is to
> > enable the feature by default. Free stack saving should be decoupled from debug_pagealloc into separate option so that it can be enabled
> > by KASAN and/or debug_pagealloc.
> 
> Right. Walter, can you do it that way, or should I?
> 
> Thanks,
> Vlastimil

I will send new patch v3.