RE: [PATCH v4 0/2] Fix and enable pmem as RAM device on arm64

[Justin He]

Hi David
> -----Original Message-----
> From: David Hildenbrand <david@xxxxxxxxxx>
> Sent: Friday, July 10, 2020 4:30 PM
> To: Justin He <Justin.He@xxxxxxx>; Catalin Marinas
> <Catalin.Marinas@xxxxxxx>; Will Deacon <will@xxxxxxxxxx>; Tony Luck
> <tony.luck@xxxxxxxxx>; Fenghua Yu <fenghua.yu@xxxxxxxxx>; Yoshinori Sato
> <ysato@xxxxxxxxxxxxxxxxxxxx>; Rich Felker <dalias@xxxxxxxx>; Dave Hansen
> <dave.hansen@xxxxxxxxxxxxxxx>; Andy Lutomirski <luto@xxxxxxxxxx>; Peter
> Zijlstra <peterz@xxxxxxxxxxxxx>; Thomas Gleixner <tglx@xxxxxxxxxxxxx>;
> Ingo Molnar <mingo@xxxxxxxxxx>; Borislav Petkov <bp@xxxxxxxxx>
> Cc: x86@xxxxxxxxxx; H. Peter Anvin <hpa@xxxxxxxxx>; Dan Williams
> <dan.j.williams@xxxxxxxxx>; Vishal Verma <vishal.l.verma@xxxxxxxxx>; Dave
> Jiang <dave.jiang@xxxxxxxxx>; Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>;
> Baoquan He <bhe@xxxxxxxxxx>; Chuhong Yuan <hslester96@xxxxxxxxx>; Mike
> Rapoport <rppt@xxxxxxxxxxxxx>; Logan Gunthorpe <logang@xxxxxxxxxxxx>;
> Masahiro Yamada <masahiroy@xxxxxxxxxx>; Michal Hocko <mhocko@xxxxxxxx>;
> linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; linux-
> ia64@xxxxxxxxxxxxxxx; linux-sh@xxxxxxxxxxxxxxx; linux-nvdimm@xxxxxxxxxxxx;
> linux-mm@xxxxxxxxx; Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>; Kaly
> Xin <Kaly.Xin@xxxxxxx>
> Subject: Re: [PATCH v4 0/2] Fix and enable pmem as RAM device on arm64
> 
> On 10.07.20 05:16, Jia He wrote:
> > This fixies a few issues when I tried to enable pmem as RAM device on
> arm64.
> >
> > To use memory_add_physaddr_to_nid as a fallback nid, it would be better
> > implement a general version (__weak) in mm/memory_hotplug. After that,
> arm64/
> > sh/s390 can simply use the general version, and PowerPC/ia64/x86 will
> use
> > arch specific version.
> >
> > Tested on ThunderX2 host/qemu "-M virt" guest with a nvdimm device. The
> > memblocks from the dax pmem device can be either hot-added or hot-
> removed
> > on arm64 guest. Also passed the compilation test on x86.
> >
> > Changes:
> > v4: - remove "device-dax: use fallback nid when numa_node is invalid",
> wait
> >       for Dan Williams' phys_addr_to_target_node() patch
> 
> So, this series no longer does what it promises? "Fix and enable pmem as
> RAM device on arm64"
> 
Hmm, a little bit awkward but seems no long what it promises. How about
sending patch1 patch2 individually without this cover-letter?

--
Cheers,
Justin (Jia He)