From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Zijlstra Subject: Re: [PATCH V4 1/2] perf ignore LBR and extra_regs. Date: Wed, 9 Jul 2014 16:16:31 +0200 Message-ID: <20140709141631.GE9918@twins.programming.kicks-ass.net> References: <1404838181-3911-1-git-send-email-kan.liang@intel.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="ILuaRSyQpoVaJ1HG" Cc: andi@firstfloor.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org To: kan.liang@intel.com Return-path: Content-Disposition: inline In-Reply-To: <1404838181-3911-1-git-send-email-kan.liang@intel.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org --ILuaRSyQpoVaJ1HG Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Tue, Jul 08, 2014 at 09:49:40AM -0700, kan.liang@intel.com wrote: > +/* > + * Under certain circumstances, access certain MSR may cause #GP. > + * The function tests if the input MSR can be safely accessed. > + */ > +static inline bool check_msr(unsigned long msr) > +{ > + u64 value; > + > + if (rdmsrl_safe(msr, &value) < 0) > + return false; > + if (wrmsrl_safe(msr, value) < 0) > + return false; > + return true; > +} What does this thing return after patch 2? does the write still fault or will KVM silently take writes too? --ILuaRSyQpoVaJ1HG Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iQIcBAEBAgAGBQJTvU66AAoJEHZH4aRLwOS6e/sP/iPnsBNTry0G/nEjfacMK61t Q6sxleac2QVj8DD6JzvjIOVOuSYULdWQmbcpPn7vaJ9yjqhphFW6MQeKvUL3gJyD 3QzVX01qmafz/NUZYOWU8dEsRwm+MuGnrRMCRSIXL+vEZsmCY7QmQmNX97NHlalB vaN5Wp3I12h6WxYOAYnrX/9SI3OMQ3TktcRE6s+4327UjitDnFcdDUxbacLiOaCy TA3HPNXhHi5kV/qmh5gTNT54gwWitCS5qtz6oupqSUZY5M5BS43tNgPzmzzcRI6u wNluZO2ctlk1WMg9pidmGO1usC0TVAMzJA87NLMbt70H2A3KQUa5Xi8YYLswgBuK bU+o10RMeAdo5C2/YiuXkqW4nd6J3220ho3x1cjmwiAPFrkx7ha05B0IA8NfLb2E 55WNMztAwn7D1gdWp4jm2gtgO01RAoY5K/STUVLockp5s0ZgByXGteIWTVRSoGke sfxE/AfHhfSK5jY53iNXB+WO0IjVV3sDIZeO5PsavNkdU69W2kR6LiQU7c4C5nhU H8hLhlQYsxrPhSN+RftPtYGAgNw9p/cz07kZCPF4gxrVX1lcBZ4BEfg2Gli7753l lAmfjR7Oui4iLkPty5Hd5KSjKrVSCH0Xu6tHHVjUbnWRMfPQendERizMPDnEzVBx AW8reqbFAnOqe/g294Cn =tbGS -----END PGP SIGNATURE----- --ILuaRSyQpoVaJ1HG--