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Peter Anvin" , Juergen Gross , Jiri Slaby , Kees Cook , kvm list , LKML , Thomas Hellstrom , Linux Virtualization , X86 ML , Sean Christopherson Subject: Re: Should SEV-ES #VC use IST? (Re: [PATCH] Allow RDTSC and RDTSCP from userspace) Message-ID: <20200623161355.GF32590@zn.tnic> References: <20200623113007.GH31822@suse.de> <20200623114818.GD4817@hirez.programming.kicks-ass.net> <20200623120433.GB14101@suse.de> <20200623125201.GG4817@hirez.programming.kicks-ass.net> <20200623134003.GD14101@suse.de> <20200623135916.GI4817@hirez.programming.kicks-ass.net> <20200623145344.GA117543@hirez.programming.kicks-ass.net> <20200623145914.GF14101@suse.de> <20200623152326.GL4817@hirez.programming.kicks-ass.net> <56af2f70-a1c6-aa64-006e-23f2f3880887@citrix.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <56af2f70-a1c6-aa64-006e-23f2f3880887@citrix.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jun 23, 2020 at 04:39:26PM +0100, Andrew Cooper wrote: > P.S. did you also hear that with Rowhammer, userspace has a nonzero > quantity of control over generating #MC, depending on how ECC is > configured on the platform. Where does that #MC point to? Can it control for which address to flip the bits for, i.e., make the #MC appear it has been generated for an address in kernel space? -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette