> -----Original Message----- > From: Jan Beulich [mailto:jbeul...@suse.com] > Sent: Thursday, September 1, 2016 4:21 PM > To: Wu, Feng <feng...@intel.com> > Cc: andrew.coop...@citrix.com; dario.faggi...@citrix.com; > george.dun...@eu.citrix.com; Tian, Kevin <kevin.t...@intel.com>; xen- > de...@lists.xen.org > Subject: Re: [PATCH v3 2/6] VMX: Properly handle pi when all the assigned > devices are removed > > >>> On 31.08.16 at 05:56, <feng...@intel.com> wrote: > > This patch handles some concern cases when the last assigned device > > is removed from the domain. In this case we should carefully handle > > pi descriptor and the per-cpu blocking list, to make sure: > > - all the PI descriptor are in the right state when next time a > > devices is assigned to the domain again. > > - No remaining vcpus of the domain in the per-cpu blocking list. > > > > Basically, we pause the domain before zapping the PI hooks and > > removing the vCPU from the blocking list, then unpause it after > > that. > > > > Signed-off-by: Feng Wu <feng...@intel.com> > > Looks plausible, but > a) as already for patch 1 I'm missing information on what changed > since v2 and
The biggest changes since v2 is that we use domain pause/unpause (suggested by George) to handle the concern case, while v2 was using some ugly and tricky method to do it, which was considered as hard to maintain. > b) doesn't this make unnecessary patch 1? The purpose of patch 1 is to make sure the two hooks are installed while CPU side PI is available event VT-d PI is not supported, I cannot see why this patch will make it unnecessary. Thanks, Feng > > Jan _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org https://lists.xen.org/xen-devel
