On Wed, 17 Nov 2021 17:39:59 +0000, David Woodhouse <dwmw2@xxxxxxxxxxxxx> wrote: > > From: David Woodhouse <dwmw@xxxxxxxxxxxx> > > The kvm_dirty_ring_get() function uses kvm_get_running_vcpu() to work out > which dirty ring to use, but there are some use cases where that doesn't > work. > > There's one in setting the Xen shared info page, introduced in commit > 629b5348841a ("KVM: x86/xen: update wallclock region") and reported by > "butt3rflyh4ck" <butterflyhuangxx@xxxxxxxxx> in > https://lore.kernel.org/kvm/CAFcO6XOmoS7EacN_n6v4Txk7xL7iqRa2gABg3F7E3Naf5uG94g@xxxxxxxxxxxxxx/ > > There's also about to be another one when the newly-reintroduced > gfn_to_pfn_cache needs to mark a page as dirty from the MMU notifier > which invalidates the mapping. In that case, we will *know* the vcpu > that can be 'blamed' for dirtying the page, and we just need to be > able to pass it in as an explicit argument when doing so. > > This patch preemptively resolves the second issue, and paves the way > for resolving the first. A complete fix for the first issue will need > us to switch the Xen shinfo to be owned by a particular vCPU, which > will happen in a separate patch. > > Signed-off-by: David Woodhouse <dwmw@xxxxxxxxxxxx> > --- > arch/arm64/kvm/mmu.c | 2 +- > arch/x86/kvm/mmu/mmu.c | 2 +- > arch/x86/kvm/mmu/spte.c | 2 +- > arch/x86/kvm/mmu/tdp_mmu.c | 2 +- > arch/x86/kvm/x86.c | 4 ++-- > include/linux/kvm_dirty_ring.h | 6 ++++-- > include/linux/kvm_host.h | 3 ++- > virt/kvm/dirty_ring.c | 8 ++++++-- > virt/kvm/kvm_main.c | 18 +++++++++--------- > 9 files changed, 27 insertions(+), 20 deletions(-) What's the base for this series? This patch fails to compile for me (at least on arm64), and the following patch doesn't apply on -rc1. Thanks, M. -- Without deviation from the norm, progress is not possible.