From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andre Przywara Date: Fri, 26 Apr 2013 16:14:18 +0200 Subject: [U-Boot] [RFC PATCH 0/6] ARMv7: Add HYP mode switching support In-Reply-To: References: <1366982099-22360-1-git-send-email-andre.przywara@linaro.org> <517A7FFA.2010000@linaro.org> Message-ID: <517A8BBA.1030803@linaro.org> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de On 04/26/2013 03:42 PM, Peter Maydell wrote: > On 26 April 2013 14:24, Andre Przywara wrote: >> On 04/26/2013 03:18 PM, Peter Maydell wrote: >>> The obvious question here is "why do we need a new command?". >>> The kernel booting specification says "boot the kernel in >>> Hyp mode" so we should just always do that for booting Linux, >>> surely? > >> Because it avoids regressions. I kind of feel uneasy to do a lot of >> tinkering with secure state and the GIC unconditionally, especially if >> enabled on many boards with virt-capable CPUs. > > There aren't exactly very many of those out there, so if we > default to "boot in HYP mode" then (a) KVM will just work > out of the box and (b) people doing u-boot ports to their > board will find any issues and be able to submit fixes. > If we don't turn it on by default then we'll end up stuck > in a world where KVM doesn't work on half the virt capable > boards out there. OK, that's a point. I changed the code already and will include it in the next revision. Thanks, Andre. > > I have no objection to a "turn this off" escape hatch if > you think it's useful. > > -- PMM >