> -----Original Message----- > From: Xen-devel <xen-devel-boun...@lists.xenproject.org> On Behalf Of Jan > Beulich > Sent: 03 March 2020 10:17 > To: xen-devel@lists.xenproject.org > Cc: Andrew Cooper <andrew.coop...@citrix.com>; Roger Pau Monné > <roger....@citrix.com>; Wei Liu <w...@xen.org>; Paul Durrant <p...@xen.org> > Subject: [EXTERNAL][Xen-devel] [PATCH v5 1/4] x86/HVM: cancel emulation > when register state got altered > > Re-execution (after having received data from a device model) relies on > the same register state still being in place as it was when the request > was first sent to the device model. Therefore vCPU state changes > effected by remote sources need to result in no attempt of re-execution. > Instead the returned data is to simply be ignored. > > Note that any such asynchronous state changes happen with the vCPU at > least paused (potentially down and/or not marked ->is_initialised), so > there's no issue with fiddling with register state behind the actively > running emulator's back. Hence the new function doesn't need to > synchronize with the core emulation logic. > > Suggested-by: Andrew Cooper <andrew.coop...@citrix.com> > Signed-off-by: Jan Beulich <jbeul...@suse.com>
Need we be concerned with any page-split I/O here? That may manifest as two separate emulations and AFAICT it would be possible for only the second part to be aborted by this change. Paul _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel
