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Date:   Thu, 25 Oct 2018 14:29:01 +0900
From:   Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
To:     Rafael David Tinoco <rafael.tinoco@linaro.org>
Cc:     linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-mm@kvack.org, Russell King <linux@armlinux.org.uk>,
        Mark Brown <broonie@kernel.org>,
        Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>,
        Nitin Gupta <ngupta@vflare.org>,
        Minchan Kim <minchan@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH 1/2] mm/zsmalloc.c: check encoded object value overflow
 for PAE
Message-ID: <20181025052901.GA17799@jagdpanzerIV>
References: <20181025012745.20884-1-rafael.tinoco@linaro.org>
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On (10/24/18 22:27), Rafael David Tinoco wrote:
>  static unsigned long location_to_obj(struct page *page, unsigned int obj_idx)
>  {
> -	unsigned long obj;
> +	unsigned long obj, pfn;
> +
> +	pfn = page_to_pfn(page);
> +
> +	if (unlikely(OBJ_OVERFLOW(pfn)))
> +		BUG();

The trend these days is to have less BUG/BUG_ON-s in the kernel.

	-ss