From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paolo Bonzini Subject: Re: [PATCH v13 6/7] arm: KVM: dirty log read write protect support Date: Sat, 08 Nov 2014 08:28:50 +0100 Message-ID: <545DC632.6020002@redhat.com> References: <1415320848-13813-1-git-send-email-m.smarduch@samsung.com> <1415320848-13813-7-git-send-email-m.smarduch@samsung.com> <545C76E9.5090700@redhat.com> <545D21BE.2020203@samsung.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Cc: james.hogan@imgtec.com, christoffer.dall@linaro.org, agraf@suse.de, marc.zyngier@arm.com, cornelia.huck@de.ibm.com, borntraeger@de.ibm.com, catalin.marinas@arm.com, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, kvm-ppc@vger.kernel.org, kvm-ia64@vger.kernel.org, linux-arm-kernel@lists.infradead.org, steve.capper@arm.com, peter.maydell@linaro.org To: Mario Smarduch Return-path: In-Reply-To: <545D21BE.2020203@samsung.com> Sender: kvm-ppc-owner@vger.kernel.org List-Id: kvm.vger.kernel.org On 07/11/2014 20:47, Mario Smarduch wrote: >> That can happen if the error occurred in the final >> copy to userspace, after page tables have been modified. > > Upon error return userspace should terminate logging, error out whether > used for migration or other use cases, with some stale spte TLBs cached > read/write, which doesn't appear to be harmful. Fair enough; for x86 I elected to always do the TLB flush, but you can do it differently. Perhaps add a comment with the above paragraph, thouhg. > But you mention 'final copy' which makes me think I'm missing something? I meant final copy before leaving the function. Paolo