From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:55499) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ez8Oo-0003Hf-8k for qemu-devel@nongnu.org; Thu, 22 Mar 2018 18:09:31 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ez8Ok-0001Eu-UF for qemu-devel@nongnu.org; Thu, 22 Mar 2018 18:09:30 -0400 Received: from mx1.redhat.com ([209.132.183.28]:45998) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1ez8Ok-0001El-Ox for qemu-devel@nongnu.org; Thu, 22 Mar 2018 18:09:26 -0400 Date: Thu, 22 Mar 2018 22:09:24 +0000 From: "Richard W.M. Jones" Message-ID: <20180322220924.GJ2787@redhat.com> References: <1521221171-47213-1-git-send-email-mjc@sifive.com> <20180319194242.GQ2787@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Subject: Re: [Qemu-devel] [PATCH v3] RISC-V: Fix riscv_isa_string memory size bug List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Michael Clark , dj@redhat.com Cc: Philippe =?iso-8859-1?Q?Mathieu-Daud=E9?= , QEMU Developers , Palmer Dabbelt , Peter Maydell On Thu, Mar 22, 2018 at 02:06:24PM -0700, Michael Clark wrote: > On Mon, Mar 19, 2018 at 2:39 PM, Michael Clark wrote: > > On Mon, Mar 19, 2018 at 12:42 PM, Richard W.M. Jones > > wrote: > >> Did you see the problem with restoring floating point registers on > >> context switch? The test case is quite simple: > >> > >> http://oirase.annexia.org/tmp/sched.c > > > > No I didn't. Thanks. > From my local testing, it appears to only show up with SMP enabled. With 1 > CPU enabled the sched.c test passes. > I'll could try and revert this and see if it makes any difference... > however I think the float code has changed substantially with respect to > handling of flags. We could backport the more conservative approach of > handling MSTATUS_FS in the float routines. We should also run the test case > on hardware to rule out linux-kernel MSTATUS_FS bugs... DJ, am I remembering correctly that you tried the test case on the HiFive evaluation board and it didn't demonstrate the bug? Rich. -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones Read my programming and virtualization blog: http://rwmj.wordpress.com libguestfs lets you edit virtual machines. Supports shell scripting, bindings from many languages. http://libguestfs.org