On 02/14/2011 03:09 PM, Tejun Heo wrote: > On Mon, Feb 14, 2011 at 02:14:57PM +0100, Milan Broz wrote: >>> But it doesn't fix the read-only snapshot issue and I guess there will be >>> the same problem with read-only MD code too. >>> (so the 2) issue here https://lkml.org/lkml/2011/2/12/209). > > So, the problem is caused by dm opening members rw even for ro > devices, right? The patch uncover these shortcomings in code. (Unfortunately quite late in RC...) >> I am not sure if this is complete fix... note that: >> - what happens during mirror resync and read-only log? >> - for COW, it there situation we need to update header in read-oly mode? (invalidated snap?) > > But if the underlying device is marked ro, dm shouldn't update it at > all. The device should be opened ro and ro policy should be enforced. Sure. So we need to check these situations I described. Btw the same pattern is in MD code in lock_rdev() ... Milan -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
