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From: Michal Hocko <mhocko@kernel.org>
To: "Chenjie (K)" <chenjie6@huawei.com>
Cc: linux-mm@kvack.org, akpm@linux-foundation.org,
	linux-kernel@vger.kernel.org, David.Woodhouse@intel.com,
	zhihui.gao@huawei.com, panxuesong@huawei.com
Subject: Re: [PATCH] memory:bugxfix panic on cat or write /dev/kmem
Date: Mon, 27 Jun 2016 13:37:57 +0200	[thread overview]
Message-ID: <20160627113757.GH31799@dhcp22.suse.cz> (raw)
In-Reply-To: <576DDC46.6050607@huawei.com>

On Sat 25-06-16 09:20:06, Chenjie (K) wrote:
> 
> 
> On 2016/6/23 20:42, Michal Hocko wrote:
> > On Fri 24-06-16 01:30:10, chenjie6@huawei.com wrote:
> > > From: chenjie <chenjie6@huawei.com>
> > > 
> > > cat /dev/kmem and echo > /dev/kmem will lead panic
> > 
> > Writing to /dev/kmem without being extremely careful is a disaster AFAIK
> > and even reading from the file can lead to unexpected results. Anyway
> > I am trying to understand what exactly you are trying to fix here. Why
> > writing to/reading from zero pfn should be any special wrt. any other
> > potentially dangerous addresses
> > 
> 
> cat /dev/mem not panic. cat /dev/kmem, just the user's operation for
> nothing.

I am sorry, but I do not follow. Could you be more specific please?
-- 
Michal Hocko
SUSE Labs

      reply	other threads:[~2016-06-27 11:38 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-06-23 17:30 [PATCH] memory:bugxfix panic on cat or write /dev/kmem chenjie6
2016-06-23 12:42 ` Michal Hocko
2016-06-25  1:20   ` Chenjie (K)
2016-06-27 11:37     ` Michal Hocko [this message]

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