[{"id":1760615,"web_url":"http://patchwork.ozlabs.org/comment/1760615/","msgid":"<20170831034236.GE22549@fergus.ozlabs.ibm.com>","list_archive_url":null,"date":"2017-08-31T03:42:36","subject":"Re: [PATCH] KVM: PPC: Book3S HV: Fix case where HDEC is treated as\n\t32-bit on POWER9","submitter":{"id":67079,"url":"http://patchwork.ozlabs.org/api/people/67079/","name":"Paul Mackerras","email":"paulus@ozlabs.org"},"content":"On Fri, Aug 25, 2017 at 07:52:12PM +1000, Paul Mackerras wrote:\n> Commit 2f2724630f7a (\"KVM: PPC: Book3S HV: Cope with host using large\n> decrementer mode\", 2017-05-22) added code to treat the hypervisor\n> decrementer (HDEC) as a 64-bit value on POWER9 rather than 32-bit.\n> Unfortunately, that commit missed one place where HDEC is treated\n> as a 32-bit value. This fixes it.\n> \n> This bug should not have any user-visible consequences that I can\n> think of, beyond an occasional unnecessary exit to the host kernel.\n> If the hypervisor decrementer has gone negative, then the bottom\n> 32 bits will be negative for about 4 seconds after that, so as\n> long as we get out of the guest within those 4 seconds we won't\n> conclude that the HDEC interrupt is spurious.\n> \n> Reported-by: Suraj Jitindar Singh \n> Fixes: 2f2724630f7a (\"KVM: PPC: Book3S HV: Cope with host using large decrementer mode\")\n> Signed-off-by: Paul Mackerras \n\nPatch applied to my kvm-ppc-next branch.\n\nPaul.\n--\nTo unsubscribe from this list: send the line \"unsubscribe kvm-ppc\" in\nthe body of a message to majordomo@vger.kernel.org\nMore majordomo info at http://vger.kernel.org/majordomo-info.html","headers":{"Return-Path":"","X-Original-To":"incoming@patchwork.ozlabs.org","Delivered-To":"patchwork-incoming@bilbo.ozlabs.org","Authentication-Results":["ozlabs.org;\n\tspf=none (mailfrom) smtp.mailfrom=vger.kernel.org\n\t(client-ip=209.132.180.67; helo=vger.kernel.org;\n\tenvelope-from=kvm-ppc-owner@vger.kernel.org;\n\treceiver=)","ozlabs.org;\n\tdkim=fail reason=\"signature verification failed\" (2048-bit key;\n\tsecure) header.d=ozlabs.org header.i=@ozlabs.org header.b=\"Ft/a1Nlg\";\n\tdkim-atps=neutral"],"Received":["from vger.kernel.org (vger.kernel.org [209.132.180.67])\n\tby ozlabs.org (Postfix) with ESMTP id 3xjSss0Vrmz9t2M\n\tfor ;\n\tThu, 31 Aug 2017 13:44:17 +1000 (AEST)","(majordomo@vger.kernel.org) by vger.kernel.org via listexpand\n\tid S1751276AbdHaDoN (ORCPT );\n\tWed, 30 Aug 2017 23:44:13 -0400","from ozlabs.org ([103.22.144.67]:42141 \"EHLO ozlabs.org\"\n\trhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP\n\tid S1751237AbdHaDoK (ORCPT );\n\tWed, 30 Aug 2017 23:44:10 -0400","by ozlabs.org (Postfix, from userid 1003)\n\tid 3xjSsj22Vzz9sNc; Thu, 31 Aug 2017 13:44:08 +1000 (AEST)"],"DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=ozlabs.org; s=201707; \n\tt=1504151049; bh=zcQjqryIbnLTBlPtla/fqY47zwprrVFf83GBGanEIew=;\n\th=Date:From:To:Subject:References:In-Reply-To:From;\n\tb=Ft/a1NlgAU88jjmrjVysO8yIK1B5FLsYxflD6mQBnNr0jZZePzzZUqvFkAdHOPgXT\n\tBgW3tCnvN/FnsGA1e3uy6lDkMN4W9tV7gkmGr71YZoNK284dc4kA4n7X0xkPcyH5bu\n\tOzkeF2EPxF+DHUGENtrhhbILiD76iIGnu2lazyhCZ+cA7UKkHtaoB5M0tXq7KFRQPa\n\tP8G+Ai9lcRl5ebHx5F2XvAN15WCiBPQWJO2ixTdNGIfHMSMH6CPB6CHKaVXcQMRdVl\n\tuPc6Pb0sXZcNStJzf4ziVIpBqnSwrqoA2oOWXav0HOs7hHREi7H5JLz4Ss/iHE3WYu\n\t7EXeGQ0Su/V8w==","Date":"Thu, 31 Aug 2017 13:42:36 +1000","From":"Paul Mackerras ","To":"kvm@vger.kernel.org, kvm-ppc@vger.kernel.org","Subject":"Re: [PATCH] KVM: PPC: Book3S HV: Fix case where HDEC is treated as\n\t32-bit on POWER9","Message-ID":"<20170831034236.GE22549@fergus.ozlabs.ibm.com>","References":"<20170825095212.GB14035@fergus.ozlabs.ibm.com>","MIME-Version":"1.0","Content-Type":"text/plain; charset=us-ascii","Content-Disposition":"inline","In-Reply-To":"<20170825095212.GB14035@fergus.ozlabs.ibm.com>","User-Agent":"Mutt/1.5.24 (2015-08-30)","Sender":"kvm-ppc-owner@vger.kernel.org","Precedence":"bulk","List-ID":"","X-Mailing-List":"kvm-ppc@vger.kernel.org"}}]