Hi,
It look like commit 6bdb913f0a70a4dfb7f066fb15e2d6f960701d00 break the
semantic of set_pte_at_notify.
The change of calling first to mmu_notifier_invalidate_range_start, then
to set_pte_at_notify, and then to mmu_notifier_invalidate_range_end
not only increase the amount of locks kvm have to take and release by
factor of 3, but in addition mmu_notifier_invalidate_range_start is zapping
the pte entry from kvm, so when set_pte_at_notify get called, it doesn`t
have any spte to set and it acctuly get called for nothing, the result is
increasing of vmexits for kvm from both do_wp_page and replace_page, and
broken semantic of set_pte_at_notify.
Thanks.
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>