Re: [libvirt] [PATCHv2 2/2] qemu: add separate rerror_policy for disk errors

Previously libvirt's disk device XML only had a single attribute, error_policy, to control both read and write error policy, but qemu has separate options for controlling read and write. In one case (enospc) a policy is allowed for write errors but not read errors. This patch adds a separate attribute that sets only the read error policy. If just error_policy is set, it will apply to both read and write error policy (previous behavior), but if the new rerror_policy attribute is set, it will override error_policy for read errors only. Possible values for rerror_policy are "stop", "report", and "ignore" ("report" is the qemu-controlled default for rerror_policy when error_policy isn't specified). For consistency, the value "report" has been added to the possible values for error_policy as well.