From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joerg Roedel Subject: Re: [PATCH] iommu/rockchip: Perform a reset on shutdown Date: Thu, 15 Mar 2018 15:12:10 +0100 Message-ID: <20180315141210.yb6c6tbzietiuty3@8bytes.org> References: <20180220202504.19275-1-marc.zyngier@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20180220202504.19275-1-marc.zyngier@arm.com> Sender: linux-kernel-owner@vger.kernel.org To: Marc Zyngier Cc: Heiko Stuebner , Robin Murphy , iommu@lists.linux-foundation.org, linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org, linux-kernel@vger.kernel.org List-Id: iommu@lists.linux-foundation.org On Tue, Feb 20, 2018 at 08:25:04PM +0000, Marc Zyngier wrote: > Trying to do a kexec whilst the iommus are still on is proving to be > a challenging exercise. It is terribly unsafe, as we're reusing the > memory allocated for the page tables, leading to a likely crash. > > Let's implement a shutdown method that will at least try to stop > DMA from going crazy behind our back. Note that we need to be > extra cautious when doing so, as the IOMMU may not be clocked > if controlled by a another master, as typical on Rockchip system. > > Suggested-by: Robin Murphy > Signed-off-by: Marc Zyngier Applied, thanks.