On 20.09.2017 16:30, Daniel P. Berrange wrote: > On Wed, Sep 20, 2017 at 02:58:55PM +0300, Nikolay Shirokovskiy wrote: >> saferead is not suitable for direct reads. If file size is not multiple >> of align size then we get EINVAL on the read(2) that is supposed to >> return 0 because read buffer will not be aligned at this point. >> >> Let's not read again after partial read and check that we read >> everything by comparing the number of total bytes read against file size. > > What scenario did you actually hit this problem in ? IIUC, we should > only be using O_DIRECT against block devices or plain files, and in both > those cases we should never see short-read unless we hit EOF. Yes. But saferead is generic function and rereads file after short read. Here we got EINVAL because of misalignement. Nikolay -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list
