On Thu, 2013-09-19 at 23:19 -0500, Bhushan Bharat-R65777 wrote: > > > -----Original Message----- > > From: Wood Scott-B07421 > > Sent: Friday, September 20, 2013 2:38 AM > > To: Bhushan Bharat-R65777 > > Cc: benh@xxxxxxxxxxxxxxxxxxx; agraf@xxxxxxx; paulus@xxxxxxxxx; > > kvm@xxxxxxxxxxxxxxx; kvm-ppc@xxxxxxxxxxxxxxx; linuxppc-dev@xxxxxxxxxxxxxxxx; > > Bhushan Bharat-R65777 > > Subject: Re: [PATCH 5/6 v5] kvm: booke: clear host tlb reference flag on guest > > tlb invalidation > > > > This breaks when you have both E500_TLB_BITMAP and E500_TLB_TLB0 set. > > I do not see any case where we set both E500_TLB_BITMAP and > E500_TLB_TLB0. This would happen if you have a guest TLB1 entry that is backed by some 4K pages and some larger pages (e.g. if the guest maps CCSR with one big TLB1 and there are varying I/O passthrough regions mapped). It's not common, but it's possible. > Also we have not optimized that yet (keeping track of > multiple shadow TLB0 entries for one guest TLB1 entry) This is about correctness, not optimization. > We uses these bit flags only for TLB1 and if size of stlbe is 4K then > we set E500_TLB_TLB0 otherwise we set E500_TLB_BITMAP. Although I > think that E500_TLB_BITMAP should be set only if stlbe size is less > than gtlbe size. Why? Even if there's only one bit set in the map, we need it to keep track of which entry was used. -Scott -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
