>-----Original Message----- >From: Peter Xu <pet...@redhat.com> >Sent: Friday, June 9, 2023 9:37 PM >To: Duan, Zhenzhong <zhenzhong.d...@intel.com> >Cc: qemu-devel@nongnu.org; m...@redhat.com; jasow...@redhat.com; >pbonz...@redhat.com; richard.hender...@linaro.org; edua...@habkost.net; >marcel.apfelb...@gmail.com; alex.william...@redhat.com; >c...@redhat.com; da...@redhat.com; phi...@linaro.org; >kwankh...@nvidia.com; c...@nvidia.com; Liu, Yi L <yi.l....@intel.com>; Peng, >Chao P <chao.p.p...@intel.com> >Subject: Re: [PATCH v3 4/5] intel_iommu: Fix address space unmap > >On Fri, Jun 09, 2023 at 03:31:46AM +0000, Duan, Zhenzhong wrote: >> >> >> >-----Original Message----- >> >From: Peter Xu <pet...@redhat.com> >> >Sent: Thursday, June 8, 2023 9:48 PM >> >To: Duan, Zhenzhong <zhenzhong.d...@intel.com> >> >Cc: qemu-devel@nongnu.org; m...@redhat.com; jasow...@redhat.com; >> >pbonz...@redhat.com; richard.hender...@linaro.org; >> >edua...@habkost.net; marcel.apfelb...@gmail.com; >> >alex.william...@redhat.com; c...@redhat.com; da...@redhat.com; >> >phi...@linaro.org; kwankh...@nvidia.com; c...@nvidia.com; Liu, Yi L >> ><yi.l....@intel.com>; Peng, Chao P <chao.p.p...@intel.com> >> >Subject: Re: [PATCH v3 4/5] intel_iommu: Fix address space unmap >> > >> >On Thu, Jun 08, 2023 at 05:52:30PM +0800, Zhenzhong Duan wrote: >> >> During address space unmap, corresponding IOVA tree entries are >> >> also removed. But DMAMap is set beyond notifier's scope by 1, so in >> >> theory there is possibility to remove a continuous entry above the >> >> notifier's scope but falling in adjacent notifier's scope. >> > >> >This function is only called in "loop over all notifiers" case (or >> >replay() that just got removed, but even so there'll be only 1 >> >notifier normally iiuc at least for vt-d), hopefully it means no bug >> >exist (no Fixes needed, no backport needed either), but still worth fixing >> >it >up. >> >> Not two notifiers as vtd-ir splits for vt-d? > >The two notifiers will all be attached to the same IOMMU mr, so >IOMMU_NOTIFIER_FOREACH() will loop over them all always? Yes. > >And this actually shouldn't matter, IMHO, as the IR split has the 0xfeeXXXXX >hole only, so when notifying with end=0xfee00000 (comparing to >end=0xfedfffff) it shouldn't make a difference iiuc because there should have >no iova entry at 0xfee00000 anyway in the tree. Clear.
Thanks Zhenzhong
