| Message ID | 1445294398-17487-1-git-send-email-kamal@canonical.com |
|---|---|
| State | New |
| Headers | show |
diff --git a/drivers/base/node.c b/drivers/base/node.c index a3b82e9..672e83e 100644 --- a/drivers/base/node.c +++ b/drivers/base/node.c @@ -390,6 +390,16 @@ 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, + PAGES_PER_SECTION) - 1; + continue; + } + page_nid = get_nid_for_pfn(pfn); if (page_nid < 0) continue;
This is a note to let you know that I have just added a patch titled mm: check if section present during memory block registering to the linux-3.19.y-queue branch of the 3.19.y-ckt extended stable tree which can be found at: http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.19.y-queue This patch is scheduled to be released in version 3.19.8-ckt8. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.19.y-ckt tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ------ From d16bccea97ec96192483c6ee8280b4a645bc8643 Mon Sep 17 00:00:00 2001 From: Yinghai Lu <yinghai@kernel.org> Date: Fri, 4 Sep 2015 15:42:39 -0700 Subject: mm: check if section present during memory block registering commit 04697858d89e4bf2650364f8d6956e2554e8ef88 upstream. 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> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- drivers/base/node.c | 10 ++++++++++ 1 file changed, 10 insertions(+) -- 1.9.1