On 14.06.2023 15:23, Roger Pau Monné wrote: > On Wed, Jun 14, 2023 at 02:58:14PM +0200, Jan Beulich wrote: >> On 14.06.2023 10:32, Roger Pau Monne wrote: >>> When the passed domain is DomIO iterate over the list of DomIO >>> assigned devices and flush each pseudo-domid found. >>> >>> invalidate_all_domain_pages() does call amd_iommu_flush_all_pages() >>> with DomIO as a parameter, >> >> Does it? Since the full function is visible in the patch (because of >> the "While there ..." change), it seems pretty clear that it doesn't: >> for_each_domain() iterates over ordinary domains only. > > Oh, I got confused by domain_create() returning early for system > domains. > >>> and hence the underlying >>> _amd_iommu_flush_pages() implementation must be capable of flushing >>> all pseudo-domids used by the quarantine domain logic. >> >> While it didn't occur to me right away when we discussed this, it >> may well be that I left alone all flushing when introducing the pseudo >> domain IDs simply because no flushing would ever happen for the >> quarantine domain. > > But the purpose of the calls to invalidate_all_devices() and > invalidate_all_domain_pages() in amd_iommu_resume() is to cover up for > the lack of Invalidate All support in the IOMMU, so flushing > pseudo-domids is also required in order to flush all possible IOMMU > state. > > Note that as part of invalidate_all_devices() we do invalidate DTEs > for devices assigned to pseudo-domids, hence it seems natural that we > also flush such pseudo-domids. > >>> While there fix invalidate_all_domain_pages() to only attempt to flush >>> the domains that have IOMMU enabled, otherwise the flush is pointless. >> >> For the moment at least it looks to me as if this change alone wants >> to go in. > > I would rather get the current patch with an added call to flush > dom_io in invalidate_all_domain_pages().
The question is: Is there anything that needs flushing for the quarantine domain. Right now I'm thinking that there isn't. Jan
