On Tue, Jun 28, 2016 at 1:31 AM, Yigal Korman <[email protected]> wrote: > Before this patch, passing a range that is beyond the physical memory > range will succeed, the user will see a /dev/pmem0 and will be able to > access it. Reads will always return 0 and writes will be silently > ignored. > > I've gotten more than one bug report about mkfs.{xfs,ext4} or nvml > failing that were eventually tracked down to be wrong values passed to > memmap. > > This patch prevents the above issue by instead of adding a new memory > range, only update a RAM memory range with the PRAM type. This way, > passing the wrong memmap will either not give you a pmem at all or give > you a smaller one that actually has RAM behind it. > > And if someone still needs to fake a pmem that doesn't have RAM behind > it, they can simply do memmap=XX@YY,XX!YY. > > Signed-off-by: Yigal Korman <[email protected]> > Acked-by: Dan Williams <[email protected]> > Acked-by: Johannes Thumshirn <[email protected]> > Tested-by: Boaz Harrosh <[email protected]> > ---
I have some other libnvdimm fixes heading upstream shortly if x86 folks just want to ack this one...
