From mboxrd@z Thu Jan  1 00:00:00 1970
From: Sasha Levin <sasha.levin@oracle.com>
Subject: Re: fs,seq_file: huge allocations for seq file reads
Date: Tue, 08 Apr 2014 10:51:27 -0400
Message-ID: <53440CEF.7090408@oracle.com>
References: <53440B8B.1010304@oracle.com> <20140408144943.GA6165@redhat.com>
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To: Dave Jones <davej@redhat.com>,
	linux-fsdevel <linux-fsdevel@vger.kernel.org>,
	Al Viro <viro@ZenIV.linux.org.uk>,
	LKML <linux-kernel@vger.kernel.org>, Greg KH <greg@kroah.com>
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On 04/08/2014 10:49 AM, Dave Jones wrote:
> On Tue, Apr 08, 2014 at 10:45:31AM -0400, Sasha Levin wrote:
>  
>  > It seems that when we attempt to read huge chunks of data from a seq file
>  > there would be no check for the size being read, leading to the kernel
>  > attempting to allocate huge chunks of data internally.
>  > 
>  > As far as I remember, there was a PAGE_SIZE limitation on those, but I'm
>  > not certain about that. Could someone please confirm it?
> 
> I've had this diff sitting around for a while to figure out which
> seq_file we're talking about.  I think Al wrote it, I forget..

I'll add it in.

I didn't realize it was a problem with a specific file, I thought it was
an issue with seq files in general.


Thanks,
Sasha