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McKenney" To: David Woodhouse Cc: Christian Borntraeger , peterz@infradead.org, mhillenb@amazon.de, linux-kernel@vger.kernel.org, kvm@vger.kernel.org Subject: Re: [PATCH v2] kvm/x86: Inform RCU of quiescent state when entering guest mode Reply-To: paulmck@linux.vnet.ibm.com References: <20180711174843.GX3593@linux.vnet.ibm.com> <20180711180101.3711464-1-dwmw2@infradead.org> <20180711182053.GA3593@linux.vnet.ibm.com> <20180711183645.GA23820@linux.vnet.ibm.com> <62e945ee-a58e-f9b3-279c-74cd0f5809da@de.ibm.com> <20180711202752.GC3593@linux.vnet.ibm.com> <1531342492.8759.90.camel@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <1531342492.8759.90.camel@infradead.org> User-Agent: Mutt/1.5.21 (2010-09-15) X-TM-AS-GCONF: 00 x-cbid: 18071121-0060-0000-0000-0000028AC1C9 X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00009352; HX=3.00000241; KW=3.00000007; PH=3.00000004; SC=3.00000266; SDB=6.01059948; UDB=6.00544036; IPR=6.00837868; MB=3.00022107; MTD=3.00000008; XFM=3.00000015; UTC=2018-07-11 21:06:53 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 18071121-0061-0000-0000-000045C38265 Message-Id: <20180711210910.GE3593@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2018-07-11_06:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=657 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1806210000 definitions=main-1807110222 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jul 11, 2018 at 09:54:52PM +0100, David Woodhouse wrote: > On Wed, 2018-07-11 at 13:27 -0700, Paul E. McKenney wrote: > > > > Something like this, on top of the earlier patch?  I am not at all > > confident of this patch because there might be other entry/exit > > paths I am missing.  Plus there might be RCU uses on the arch- > > specific patch to and from the guest OS. > > That was going to be my starting point, yes. With some additional > manual review and testing to cover the "not at all confident" part. :) Please feel free to change as needed, up to and including throwing my patch away and starting over. ;-) Thanx, Paul