From mboxrd@z Thu Jan  1 00:00:00 1970
From: dyoung@redhat.com (Dave Young)
Date: Tue, 13 Mar 2018 09:54:58 +0800
Subject: [Query] ARM64 kaslr support - randomness, seeding and kdump
In-Reply-To: <CAKv+Gu8qd=rpJkG_GoVO=kkmc4qx_zZD8c_wwE16gr=8wSShSw@mail.gmail.com>
References: <CACi5LpMhHt4bjEueOzHZTGpzuR2zoQqXcReL-khoSNLG6=FVmg@mail.gmail.com>
 <CAKv+Gu8qd=rpJkG_GoVO=kkmc4qx_zZD8c_wwE16gr=8wSShSw@mail.gmail.com>
Message-ID: <20180313015458.GA4352@dhcp-128-65.nay.redhat.com>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On 03/12/18 at 08:58pm, Ard Biesheuvel wrote:
[snip]
> > - We pass the dtb over to the kdump kernel for arm64 kdump, but the
> > '/chosen/kaslr-seed' property would be zeroed out already by the
> > primary kernel and the secondary would work in a *nokaslr* environment
> > due to the same (see [4] for example)
> >
> 
> What would be the point of randomizing the placement of the kdump
> kernel? And don't say 'because x86 does it', because that is not a
> good reason.

Kdump kernel does not need kaslr. Actually in Fedora we use 'nokaslr'
even for x86_64

Thanks
Dave

From mboxrd@z Thu Jan  1 00:00:00 1970
Return-path: <kexec-bounces+dwmw2=infradead.org@lists.infradead.org>
Date: Tue, 13 Mar 2018 09:54:58 +0800
From: Dave Young <dyoung@redhat.com>
Subject: Re: [Query] ARM64 kaslr support - randomness, seeding and kdump
Message-ID: <20180313015458.GA4352@dhcp-128-65.nay.redhat.com>
References: <CACi5LpMhHt4bjEueOzHZTGpzuR2zoQqXcReL-khoSNLG6=FVmg@mail.gmail.com>
 <CAKv+Gu8qd=rpJkG_GoVO=kkmc4qx_zZD8c_wwE16gr=8wSShSw@mail.gmail.com>
MIME-Version: 1.0
Content-Disposition: inline
In-Reply-To: <CAKv+Gu8qd=rpJkG_GoVO=kkmc4qx_zZD8c_wwE16gr=8wSShSw@mail.gmail.com>
List-Id: <kexec.lists.infradead.org>
List-Unsubscribe: <http://lists.infradead.org/mailman/options/kexec>,
 <mailto:kexec-request@lists.infradead.org?subject=unsubscribe>
List-Archive: <http://lists.infradead.org/pipermail/kexec/>
List-Post: <mailto:kexec@lists.infradead.org>
List-Help: <mailto:kexec-request@lists.infradead.org?subject=help>
List-Subscribe: <http://lists.infradead.org/mailman/listinfo/kexec>,
 <mailto:kexec-request@lists.infradead.org?subject=subscribe>
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit
Sender: "kexec" <kexec-bounces@lists.infradead.org>
Errors-To: kexec-bounces+dwmw2=infradead.org@lists.infradead.org
To: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>, Bhupesh Sharma <bhsharma@redhat.com>, kexec@lists.infradead.org, AKASHI Takahiro <takahiro.akashi@linaro.org>, Bhupesh SHARMA <bhupesh.linux@gmail.com>, linux-arm-kernel <linux-arm-kernel@lists.infradead.org>

On 03/12/18 at 08:58pm, Ard Biesheuvel wrote:
[snip]
> > - We pass the dtb over to the kdump kernel for arm64 kdump, but the
> > '/chosen/kaslr-seed' property would be zeroed out already by the
> > primary kernel and the secondary would work in a *nokaslr* environment
> > due to the same (see [4] for example)
> >
> 
> What would be the point of randomizing the placement of the kdump
> kernel? And don't say 'because x86 does it', because that is not a
> good reason.

Kdump kernel does not need kaslr. Actually in Fedora we use 'nokaslr'
even for x86_64

Thanks
Dave

_______________________________________________
kexec mailing list
kexec@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/kexec