Punit Agrawal 86658b819c KVM: arm/arm64: Skip updating PMD entry if no change ... Contention on updating a PMD entry by a large number of vcpus can lead to duplicate work when handling stage 2 page faults. As the page table update follows the break-before-make requirement of the architecture, it can lead to repeated refaults due to clearing the entry and flushing the tlbs. This problem is more likely when - * there are large number of vcpus * the mapping is large block mapping such as when using PMD hugepages (512MB) with 64k pages. Fix this by skipping the page table update if there is no change in the entry being updated. Cc: stable@vger.kernel.org Fixes: ad361f093c ("KVM: ARM: Support hugetlbfs backed huge pages") Reviewed-by: Suzuki Poulose <suzuki.poulose@arm.com> Acked-by: Christoffer Dall <christoffer.dall@arm.com> Signed-off-by: Punit Agrawal <punit.agrawal@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>		2018-08-13 15:31:35 +01:00
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kvm	KVM: arm/arm64: Skip updating PMD entry if no change	2018-08-13 15:31:35 +01:00
lib	KVM: eventfd: fix NULL deref irqbypass consumer	2017-01-12 14:42:34 +01:00
Makefile	virt: Add virt directory to the top Makefile	2015-10-01 15:06:44 +02:00