Because we have disk backend imitation for NVDimm kind memory, I think it is more
flexible for user to specify the real or not real pmem rather than we check in qemu using the pmem_is_pmem API ________________________________ From: Stefan Hajnoczi <[email protected]> Sent: Thursday, May 31, 2018 1:09:42 PM To: [email protected] Cc: [email protected]; Haozhong Zhang; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; Junyan He; [email protected]; [email protected]; [email protected]; [email protected] Subject: Re: [Qemu-devel] [PATCH 2/9 V5] hostmem-file: add the 'pmem' option On Thu, May 10, 2018 at 10:08:51AM +0800, [email protected] wrote: > From: Junyan He <[email protected]> > > When QEMU emulates vNVDIMM labels and migrates vNVDIMM devices, it > needs to know whether the backend storage is a real persistent memory, > in order to decide whether special operations should be performed to > ensure the data persistence. > > This boolean option 'pmem' allows users to specify whether the backend > storage of memory-backend-file is a real persistent memory. If > 'pmem=on', QEMU will set the flag RAM_PMEM in the RAM block of the > corresponding memory region. I'm still not sure if this option is necessary since pmem_is_pmem() is available with the introduction of the libpmem dependency. Why can't it be used? Stefan
