On Mon, Apr 11, 2022 at 11:35:54AM +0200, Jan Beulich wrote: > Prior extension of these functions to enable per-device quarantine page > tables already didn't add more locking there, but merely left in place > what had been there before. But really locking is unnecessary here: > We're running with pcidevs_lock held (i.e. multiple invocations of the > same function [or their teardown equivalents] are impossible, and hence > there are no "local" races), while all consuming of the data being > populated here can't race anyway due to happening sequentially > afterwards. See also the comment in struct arch_pci_dev.
I would explicitly say that none of the code in the locked region touches any data in the domain_iommu struct, so taking the mapping_lock is unneeded. Long term we might wish to implemented a per-device lock that could be used here, instead of relying on the pcidevs lock. > > Signed-off-by: Jan Beulich <jbeul...@suse.com> Reviewed-by: Roger Pau Monné <roger....@citrix.com> Thanks, Roger.
