From mboxrd@z Thu Jan 1 00:00:00 1970 From: "H. Peter Anvin" Subject: Re: [patch 0/7 v2] kexec kernel efi runtime support Date: Sun, 10 Nov 2013 18:21:09 -0800 Message-ID: <52803F15.3080204@zytor.com> References: <20131105082007.872550445@dhcp-16-126.nay.redhat.com> <20131108143118.GA22636@console-pimps.org> <20131109035739.GB4294@dhcp-16-126.nay.redhat.com> <527DC1BE.6030107@zytor.com> <20131111021356.GC4407@dhcp-16-126.nay.redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20131111021356.GC4407-je1gSBvt1TcFLmT5oZ11vB/sF2h8X+2i0E9HWUfgJXw@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "kexec" Errors-To: kexec-bounces+glkk-kexec=m.gmane.org-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org To: Dave Young Cc: Matt Fleming , linux-efi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, mjg59-1xO5oi07KQx4cg9Nei1l7Q@public.gmane.org, Greg KH , x86-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, kexec-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, James.Bottomley-d9PhHud1JfjCXq6kfMZ53/egYHeGw8Jk@public.gmane.org, horms-/R6kz+dDXgpPR4JQBCEnsQ@public.gmane.org, bp-Gina5bIWoIWzQB+pC5nmwQ@public.gmane.org, ebiederm-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org, vgoyal-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org List-Id: linux-efi@vger.kernel.org On 11/10/2013 06:13 PM, Dave Young wrote: > > Huang Ying created the debugfs file for boot_params. > His first version patch tried sysfs, but sysfs is not designed for such > binary blobs so finally it go to debugfs. > That is a misunderstanding. Binary blobs can exist in sysfs as long as the blob is something that is inherently a blob. This is admittedly a corner case, but it is without any doubt a protocol-defined binary structure. The reason it was put in debugfs is that there was no non-debug user for it at the time. > Any idea for this is welcome, till now I have no better idea for such kind > of data. We should have another *fs instead of using debugfs. The problem with debugfs is that things go into debugfs with largely no auditing. As a result, mounting debugfs is very likely to mean that your system is exploitable one way or another. -hpa