On 08/07/2015 07:07 AM, Ming Lei wrote: > On Mon, Aug 3, 2015 at 7:00 PM, Alexander Graf <ag...@suse.de> wrote: >>
[ .. ] >> >> because the guest thinks the disk is formatted with 4k sector size, >> while mkfs thought it's formatted with 512 byte sector size. > > I am wondering if mkfs is remembering the sector size of actual block > device, and at least it can't be found by 'dumpe2fs'. And it shouldn't have > do that, otherwise it isn't flexible. And one fs image often can be looped > successully by loop because loop's block size is 512. > > That is why I am wondering if we need support other logical block size > for loop. > If you were to install a bootloader (like lilo or zipl for S/390) it needs to write the _physical_ block addresses of the kernel and the initrd. And these do vary, depending in the physical blocksize. So while the filesystems indeed do not care (all translation is done in the block driver, not the filesystem), bootloaders most certainly do. If you were to create a bootable disk on 4k disks you need this patch. Cheers, Hannes -- Dr. Hannes Reinecke zSeries & Storage h...@suse.de +49 911 74053 688 SUSE LINUX GmbH, Maxfeldstr. 5, 90409 Nürnberg GF: F. Imendörffer, J. Smithard, J. Guild, D. Upmanyu, G. Norton HRB 21284 (AG Nürnberg) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
