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Date:   Wed, 29 May 2019 18:25:32 +0200
From:   Michal Hocko <mhocko@kernel.org>
To:     Dianzhang Chen <dianzhangchen0@gmail.com>
Cc:     cl@linux.com, penberg@kernel.org, rientjes@google.com,
        iamjoonsoo.kim@lge.com, akpm@linux-foundation.org,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mm/slab_common.c: fix possible spectre-v1 in
 kmalloc_slab()
Message-ID: <20190529162532.GG18589@dhcp22.suse.cz>
References: <1559133448-31779-1-git-send-email-dianzhangchen0@gmail.com>
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On Wed 29-05-19 20:37:28, Dianzhang Chen wrote:
[...]
> @@ -1056,6 +1057,7 @@ struct kmem_cache *kmalloc_slab(size_t size, gfp_t flags)
>  		if (!size)
>  			return ZERO_SIZE_PTR;
>  
> +		size = array_index_nospec(size, 193);
>  		index = size_index[size_index_elem(size)];

What is this 193 magic number?
-- 
Michal Hocko
SUSE Labs