goggin, edward wrote:
Should one be using the multi-path device-mapper mapped device
name or one of the SCSI target device names for the whole disk
device when modifying a SCSI disk's partition table with fdisk(8)?
If the former, drivers/block/ioctl.c:blkdev_reread_part()
currently returns EINVAL since the mapped device is not
partitionable. I can't imagine the recommendation is the
latter, since there is no mechanism in place to synchronize
the kernel's partition table handling amongst multiple target
devices.
--
As discussed earlier, one face of this problem is that kpartx does
buffered reads to grab the on-disk partition table, leading to
situations where kpartx ->fdisk -> kpartx sequence does not garanty
partitons-to-maps layout will reflect reality.
To address this particular problem, do you think adding O_DIRECT to the
open() call in kpartx.c would be enough ?
Regards,
cvaroqui