Received-SPF: pass (google.com: domain of linux-kernel+bounces-94891-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:45d1:ec00::1 as permitted sender) client-ip=2604:1380:45d1:ec00::1;
Date: Wed, 6 Mar 2024 18:52:52 -0800
From: Isaku Yamahata <isaku.yamahata@linux.intel.com>
To: David Matlack <dmatlack@google.com>
Cc: isaku.yamahata@intel.com, kvm@vger.kernel.org, isaku.yamahata@gmail.com,
	linux-kernel@vger.kernel.org,
	Sean Christopherson <seanjc@google.com>,
	Paolo Bonzini <pbonzini@redhat.com>,
	Michael Roth <michael.roth@amd.com>,
	Federico Parola <federico.parola@polito.it>,
	isaku.yamahata@linux.intel.com
Subject: Re: [RFC PATCH 2/8] KVM: Add KVM_MAP_MEMORY vcpu ioctl to
 pre-populate guest memory
Message-ID: <20240307025252.GH368614@ls.amr.corp.intel.com>
References: <cover.1709288671.git.isaku.yamahata@intel.com>
 <012b59708114ba121735769de94756fa5af3204d.1709288671.git.isaku.yamahata@intel.com>
 <ZekPD_L7vam2W-CJ@google.com>
Precedence: bulk
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Disposition: inline
In-Reply-To: <ZekPD_L7vam2W-CJ@google.com>

On Wed, Mar 06, 2024 at 04:49:19PM -0800,
David Matlack <dmatlack@google.com> wrote:

> > +			cond_resched();
> > +
> > +		r = kvm_arch_vcpu_map_memory(vcpu, mapping);
> > +		if (r)
> > +			break;
> > +
> > +		added = true;
> > +	}
> > +
> > +	srcu_read_unlock(&vcpu->kvm->srcu, idx);
> > +	vcpu_put(vcpu);
> > +
> > +	if (added && mapping->nr_pages > 0)
> > +		r = -EAGAIN;
> 
> This can overwrite the return value from kvm_arch_vcpu_map_memory().

This is to convert ERESTART into EAGAIN.  I'll drop this check
and document EINTR so that caller should be aware of partial population.
-- 
Isaku Yamahata <isaku.yamahata@linux.intel.com>