4.10-stable review patch. If anyone has any objections, please let me know.
------------------
From: Dan Williams <dan.j.williams@xxxxxxxxx>
commit d5483feda85a8f39ee2e940e279547c686aac30c upstream.
Fix failures to create namespaces due to the vmem_altmap not advertising
enough free space to store the memmap.
WARNING: CPU: 15 PID: 8022 at arch/x86/mm/init_64.c:656 arch_add_memory+0xde/0xf0
[..]
Call Trace:
dump_stack+0x63/0x83
__warn+0xcb/0xf0
warn_slowpath_null+0x1d/0x20
arch_add_memory+0xde/0xf0
devm_memremap_pages+0x244/0x440
pmem_attach_disk+0x37e/0x490 [nd_pmem]
nd_pmem_probe+0x7e/0xa0 [nd_pmem]
nvdimm_bus_probe+0x71/0x120 [libnvdimm]
driver_probe_device+0x2bb/0x460
bind_store+0x114/0x160
drv_attr_store+0x25/0x30
In commit 658922e57b84 "libnvdimm, pfn: fix memmap reservation sizing"
we arranged for the capacity to be allocated, but failed to also update
the 'npfns' parameter. This leads to cases where there is enough
capacity reserved to hold all the allocated sections, but
vmemmap_populate_hugepages() still encounters -ENOMEM from
altmap_alloc_block_buf().
This fix is a stop-gap until we can teach the core memory hotplug
implementation to permit sub-section hotplug.
Fixes: 658922e57b84 ("libnvdimm, pfn: fix memmap reservation sizing")
Reported-by: Anisha Allada <anisha.allada@xxxxxxxxx>
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/nvdimm/pfn_devs.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
--- a/drivers/nvdimm/pfn_devs.c
+++ b/drivers/nvdimm/pfn_devs.c
@@ -538,7 +538,8 @@ static struct vmem_altmap *__nvdimm_setu
nd_pfn->npfns = le64_to_cpu(pfn_sb->npfns);
altmap = NULL;
} else if (nd_pfn->mode == PFN_MODE_PMEM) {
- nd_pfn->npfns = (resource_size(res) - offset) / PAGE_SIZE;
+ nd_pfn->npfns = PFN_SECTION_ALIGN_UP((resource_size(res)
+ - offset) / PAGE_SIZE);
if (le64_to_cpu(nd_pfn->pfn_sb->npfns) > nd_pfn->npfns)
dev_info(&nd_pfn->dev,
"number of pfns truncated from %lld to %ld\n",
@@ -625,7 +626,8 @@ static int nd_pfn_init(struct nd_pfn *nd
*/
start += start_pad;
size = resource_size(&nsio->res);
- npfns = (size - start_pad - end_trunc - SZ_8K) / SZ_4K;
+ npfns = PFN_SECTION_ALIGN_UP((size - start_pad - end_trunc - SZ_8K)
+ / PAGE_SIZE);
if (nd_pfn->mode == PFN_MODE_PMEM) {
/*
* vmemmap_populate_hugepages() allocates the memmap array in