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Date:   Wed, 12 Apr 2023 13:51:12 +0200
From:   Michal Hocko <mhocko@suse.com>
To:     Jaewon Kim <jaewon31.kim@samsung.com>
Cc:     "jstultz@google.com" <jstultz@google.com>,
        "tjmercier@google.com" <tjmercier@google.com>,
        "sumit.semwal@linaro.org" <sumit.semwal@linaro.org>,
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        "akpm@linux-foundation.org" <akpm@linux-foundation.org>,
        "hannes@cmpxchg.org" <hannes@cmpxchg.org>,
        "linux-mm@kvack.org" <linux-mm@kvack.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "jaewon31.kim@gmail.com" <jaewon31.kim@gmail.com>
Subject: Re: [PATCH v3] dma-buf/heaps: system_heap: avoid too much allocation
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On Wed 12-04-23 20:37:59, Jaewon Kim wrote:
> Limiting dmabuf memory may be required. But I think there
> is no nice and reasonable way so far.

If that is really the way then the patch doesn't really add a big
benefit. It doesn't really prevent OOMs (or panics due to OOM) as the
allocator still allows to consume arbitrary amount of memory. The
provided check is not able to tell between buggy and legit calls.
-- 
Michal Hocko
SUSE Labs