From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoffer Dall Subject: Re: [PATCH] arm/arm64: KVM: Map the BSS at HYP Date: Mon, 24 Oct 2016 10:10:37 +0200 Message-ID: <20161024081037.GG13680@cbox> References: <1476968441-29003-1-git-send-email-marc.zyngier@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org To: Marc Zyngier Return-path: Content-Disposition: inline In-Reply-To: <1476968441-29003-1-git-send-email-marc.zyngier@arm.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu List-Id: kvm.vger.kernel.org On Thu, Oct 20, 2016 at 02:00:41PM +0100, Marc Zyngier wrote: > When used with a compiler that doesn't implement "asm goto" > (such as the AArch64 port of GCC 4.8), jump labels generate a > memory access to find out about the value of the key (instead > of just patching the code). The key itself is likely to be > stored in the BSS. > > This is perfectly fine, except that we don't map the BSS at HYP, > leading to an exploding kernel at the first access. The obvious > fix is simply to map the BSS there (which should have been done > a long while ago, but hey...). > > Reported-by: Eric Auger > Tested-by: Eric Auger > Signed-off-by: Marc Zyngier Acked-by: Christoffer Dall