On Fri, May 17, 2013 at 02:41:30PM +0200, Christian Borntraeger wrote: > Gleb, Paolo, Marcelo, > Applied, thanks. > here are some low level changes to kvm on s390 that we have been > cooking for a while now. > > Patch "s390/pgtable: fix ipte notify bit" will go via Martins > tree into 3.10, but is included to reduce the amount of merge > conflicts. > > Patch "s390: fix gmap_ipte_notifier vs. software dirty pages" > will also go via Martins tree into 3.10 and it fixes a hang with > heavy host paging and KVM. This is optional for merging, but > makes testing on kvm/next easier. > > This series addresses 2 problems: > - paging of guest prefix page > - RCU timeouts > > The first problem is basically that we must not have the host pte > invalid or r/o for the guest prefix pages. (everything else has fully > nested paging but the prefix page must not cause host faults). > It is not enough to pin the page, also the pte has to be r/w all the > time. Mlocking is not enough due to memory compaction, malicious > unmapping etc. > We use the existing callback mechanism of the s390 page table functions > to kick guests out of SIE and hold them until this is done. We cant > use the existing kick functions since we must hold a pgste lock while > we wait for SIE to exit and IPIs might dead lock. > > The second problem is that with KVM on s390 we have seen very long > RCU stalls due to SIE not exiting on interrupts. Instead of returning > to SIE, we now force an exit into the kvm module, which then does the > guest exit/enter magic, fixing rcu. > > The whole bunch is probably too complex for 3.10, so please queue for > 3.11 > > Christian Borntraeger (5): > s390/pgtable: fix ipte notify bit > s390/kvm: Mark if a cpu is in SIE > s390/kvm: Provide a way to prevent reentering SIE > s390/kvm: Kick guests out of sie if prefix page host pte is touched > s390: fix gmap_ipte_notifier vs. software dirty pages > > Martin Schwidefsky (3): > s390/kvm: fix psw rewinding in handle_skey > s390/kvm: rename RCP_xxx defines to PGSTE_xxx > s390/kvm: avoid automatic sie reentry > > arch/s390/include/asm/kvm_host.h | 8 +++- > arch/s390/include/asm/pgtable.h | 83 +++++++++++++++++++--------------------- > arch/s390/kernel/asm-offsets.c | 3 ++ > arch/s390/kernel/entry64.S | 80 ++++++++++++++++++-------------------- > arch/s390/kvm/intercept.c | 39 +------------------ > arch/s390/kvm/kvm-s390.c | 81 ++++++++++++++++++++++++++++++++++++++- > arch/s390/kvm/kvm-s390.h | 5 +++ > arch/s390/kvm/priv.c | 3 +- > arch/s390/mm/pgtable.c | 5 +-- > 9 files changed, 179 insertions(+), 128 deletions(-) > > -- > 1.8.1.4 -- Gleb. -- 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
