diff options
authorYinghai Lu <yinghai@kernel.org>2015-09-04 15:42:39 -0700
committerSasha Levin <sasha.levin@oracle.com>2015-10-27 22:14:54 -0400
commit7feb2fc286e0712a6c17fa68ae20f7aa24a475df (patch)
parentc613e5be6cd5b8c3da2fd15d5757cb4e0bd4da03 (diff)
mm: check if section present during memory block registering
[ Upstream commit 04697858d89e4bf2650364f8d6956e2554e8ef88 ] Tony Luck found on his setup, if memory block size 512M will cause crash during booting. BUG: unable to handle kernel paging request at ffffea0074000020 IP: get_nid_for_pfn+0x17/0x40 PGD 128ffcb067 PUD 128ffc9067 PMD 0 Oops: 0000 [#1] SMP Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.2.0-rc8 #1 ... Call Trace: ? register_mem_sect_under_node+0x66/0xe0 register_one_node+0x17b/0x240 ? pci_iommu_alloc+0x6e/0x6e topology_init+0x3c/0x95 do_one_initcall+0xcd/0x1f0 The system has non continuous RAM address: BIOS-e820: [mem 0x0000001300000000-0x0000001cffffffff] usable BIOS-e820: [mem 0x0000001d70000000-0x0000001ec7ffefff] usable BIOS-e820: [mem 0x0000001f00000000-0x0000002bffffffff] usable BIOS-e820: [mem 0x0000002c18000000-0x0000002d6fffefff] usable BIOS-e820: [mem 0x0000002e00000000-0x00000039ffffffff] usable So there are start sections in memory block not present. For example: memory block : [0x2c18000000, 0x2c20000000) 512M first three sections are not present. The current register_mem_sect_under_node() assume first section is present, but memory block section number range [start_section_nr, end_section_nr] would include not present section. For arch that support vmemmap, we don't setup memmap for struct page area within not present sections area. So skip the pfn range that belong to absent section. [akpm@linux-foundation.org: simplification] [rientjes@google.com: more simplification] Fixes: bdee237c0343 ("x86: mm: Use 2GB memory block size on large memory x86-64 systems") Fixes: 982792c782ef ("x86, mm: probe memory block size for generic x86 64bit") Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: David Rientjes <rientjes@google.com> Reported-by: Tony Luck <tony.luck@intel.com> Tested-by: Tony Luck <tony.luck@intel.com> Cc: Greg KH <greg@kroah.com> Cc: Ingo Molnar <mingo@elte.hu> Tested-by: David Rientjes <rientjes@google.com> Cc: <stable@vger.kernel.org> [3.15+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
1 files changed, 10 insertions, 0 deletions
diff --git a/drivers/base/node.c b/drivers/base/node.c
index 472168cd0c97..74d45823890b 100644
--- a/drivers/base/node.c
+++ b/drivers/base/node.c
@@ -396,6 +396,16 @@ int register_mem_sect_under_node(struct memory_block *mem_blk, int nid)
for (pfn = sect_start_pfn; pfn <= sect_end_pfn; pfn++) {
int page_nid;
+ /*
+ * memory block could have several absent sections from start.
+ * skip pfn range from absent section
+ */
+ if (!pfn_present(pfn)) {
+ pfn = round_down(pfn + PAGES_PER_SECTION,
+ continue;
+ }
page_nid = get_nid_for_pfn(pfn);
if (page_nid < 0)