From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marcelo Tosatti <mtosatti@redhat.com>
Subject: Re: [PATCH 1/6] kvm.git mmu notifier patch
Date: Mon, 28 Jul 2008 18:15:21 -0300
Message-ID: <20080728211521.GB8342@dmt.cnet>
References: <20080725142452.GA8217@duo.random> <20080728211104.GA8342@dmt.cnet>
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Cc: Avi Kivity <avi@qumranet.com>,
	Marcelo Tosatti <marcelo.tosatti@cyclades.com.br>,
	kvm@vger.kernel.org
To: Andrea Arcangeli <andrea@qumranet.com>
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On Mon, Jul 28, 2008 at 06:11:04PM -0300, Marcelo Tosatti wrote:
> > +static int kvm_unmap_rmapp(struct kvm *kvm, unsigned long *rmapp)
> > +{
> > +	u64 *spte;
> > +	int need_tlb_flush = 0;
> > +
> > +	while ((spte = rmap_next(kvm, rmapp, NULL))) {
                                            ^^^^^^^^

Yeah, I can't read. :-)


> > +		BUG_ON(!(*spte & PT_PRESENT_MASK));
> > +		rmap_printk("kvm_rmap_unmap_hva: spte %p %llx\n", spte, *spte);
> > +		rmap_remove(kvm, spte);
> > +		set_shadow_pte(spte, shadow_trap_nonpresent_pte);
> > +		need_tlb_flush = 1;
> > +	}
> 
> Is rmap_remove() safe during rmap_next() iteration? Don't you need to
> restart the rmap walk from the beginning?
> 
> Remember the discussion around commit
> 6597ca09e6c0e5aec7ffd2b8ab48c671d3c28414.