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d78bca7296
When the MM code is invalidating a range of pages, it calls the KVM kvm_mmu_notifier_invalidate_range_start() notifier function, which calls kvm_unmap_hva_range(), which arranges to flush all the existing host HPTEs for guest pages. However, the Linux PTEs for the range being flushed are still valid at that point. We are not supposed to establish any new references to pages in the range until the ...range_end() notifier gets called. The PPC-specific KVM code doesn't get any explicit notification of that; instead, we are supposed to use mmu_notifier_retry() to test whether we are or have been inside a range flush notifier pair while we have been getting a page and instantiating a host HPTE for the page. This therefore adds a call to mmu_notifier_retry inside kvmppc_mmu_map_page(). This call is inside a region locked with kvm->mmu_lock, which is the same lock that is called by the KVM MMU notifier functions, thus ensuring that no new notification can proceed while we are in the locked region. Inside this region we also create the host HPTE and link the corresponding hpte_cache structure into the lists used to find it later. We cannot allocate the hpte_cache structure inside this locked region because that can lead to deadlock, so we allocate it outside the region and free it if we end up not using it. This also moves the updates of vcpu3s->hpte_cache_count inside the regions locked with vcpu3s->mmu_lock, and does the increment in kvmppc_mmu_hpte_cache_map() when the pte is added to the cache rather than when it is allocated, in order that the hpte_cache_count is accurate. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de> |
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| boot | ||
| configs | ||
| crypto | ||
| include | ||
| kernel | ||
| kvm | ||
| lib | ||
| math-emu | ||
| mm | ||
| net | ||
| oprofile | ||
| perf | ||
| platforms | ||
| sysdev | ||
| xmon | ||
| Kconfig | ||
| Kconfig.debug | ||
| Makefile | ||
| relocs_check.pl | ||