Hi Dan > -----Original Message----- > From: Dan Williams <[email protected]> > Sent: Thursday, July 9, 2020 11:39 AM > To: Justin He <[email protected]> > Cc: Catalin Marinas <[email protected]>; Will Deacon > <[email protected]>; Tony Luck <[email protected]>; Fenghua Yu > <[email protected]>; Yoshinori Sato <[email protected]>; Rich > Felker <[email protected]>; Dave Hansen <[email protected]>; Andy > Lutomirski <[email protected]>; Peter Zijlstra <[email protected]>; > Thomas Gleixner <[email protected]>; Ingo Molnar <[email protected]>; > Borislav Petkov <[email protected]>; David Hildenbrand <[email protected]>; X86 > ML <[email protected]>; H. Peter Anvin <[email protected]>; Vishal Verma > <[email protected]>; Dave Jiang <[email protected]>; Andrew > Morton <[email protected]>; Baoquan He <[email protected]>; Chuhong > Yuan <[email protected]>; Mike Rapoport <[email protected]>; Logan > Gunthorpe <[email protected]>; Masahiro Yamada <[email protected]>; > Michal Hocko <[email protected]>; Linux ARM <linux-arm- > [email protected]>; Linux Kernel Mailing List <linux- > [email protected]>; [email protected]; Linux-sh <linux- > [email protected]>; linux-nvdimm <[email protected]>; Linux MM > <[email protected]>; Jonathan Cameron <[email protected]>; Kaly > Xin <[email protected]> > Subject: Re: [PATCH v3 5/6] device-dax: use fallback nid when numa_node is > invalid > > On Wed, Jul 8, 2020 at 7:07 PM Jia He <[email protected]> wrote: > > > > numa_off is set unconditionally at the end of dummy_numa_init(), > > even with a fake numa node. ACPI detects node id as NUMA_NO_NODE(-1) in > > acpi_map_pxm_to_node() because it regards numa_off as turning off the > numa > > node. Hence dev_dax->target_node is NUMA_NO_NODE on arm64 with fake numa. > > > > Without this patch, pmem can't be probed as a RAM device on arm64 if > SRAT table > > isn't present: > > $ndctl create-namespace -fe namespace0.0 --mode=devdax --map=dev -s 1g - > a 64K > > kmem dax0.0: rejecting DAX region [mem 0x240400000-0x2bfffffff] with > invalid node: -1 > > kmem: probe of dax0.0 failed with error -22 > > > > This fixes it by using fallback memory_add_physaddr_to_nid() as nid. > > > > Suggested-by: David Hildenbrand <[email protected]> > > Signed-off-by: Jia He <[email protected]> > > --- > > drivers/dax/kmem.c | 21 +++++++++++++-------- > > 1 file changed, 13 insertions(+), 8 deletions(-) > > > > diff --git a/drivers/dax/kmem.c b/drivers/dax/kmem.c > > index 275aa5f87399..218f66057994 100644 > > --- a/drivers/dax/kmem.c > > +++ b/drivers/dax/kmem.c > > @@ -31,22 +31,23 @@ int dev_dax_kmem_probe(struct device *dev) > > int numa_node; > > int rc; > > > > + /* Hotplug starting at the beginning of the next block: */ > > + kmem_start = ALIGN(res->start, memory_block_size_bytes()); > > + > > /* > > * Ensure good NUMA information for the persistent memory. > > * Without this check, there is a risk that slow memory > > * could be mixed in a node with faster memory, causing > > - * unavoidable performance issues. > > + * unavoidable performance issues. Furthermore, fallback node > > + * id can be used when numa_node is invalid. > > */ > > numa_node = dev_dax->target_node; > > if (numa_node < 0) { > > - dev_warn(dev, "rejecting DAX region %pR with invalid > node: %d\n", > > - res, numa_node); > > - return -EINVAL; > > + numa_node = memory_add_physaddr_to_nid(kmem_start); > > I think this fixup belongs to the core to set a fallback value for > dev_dax->target_node. > > I'm close to having patches to provide a functional > phys_addr_to_target_node() for arm64.
Should My this patch(5/6) wait on your new phys_addr_to_target_node() patch? Thanks for the clarification. -- Cheers, Justin (Jia He)
