Commit ae64ffca authored Nov 29, 2012 by Jianguo Wu Committed by Linus Torvalds Nov 30, 2012

mm/vmemmap: fix wrong use of virt_to_page



I enable CONFIG_DEBUG_VIRTUAL and CONFIG_SPARSEMEM_VMEMMAP, when doing
memory hotremove, there is a kernel BUG at arch/x86/mm/physaddr.c:20.

It is caused by free_section_usemap()->virt_to_page(), virt_to_page() is
only used for kernel direct mapping address, but sparse-vmemmap uses
vmemmap address, so it is going wrong here.

  ------------[ cut here ]------------
  kernel BUG at arch/x86/mm/physaddr.c:20!
  invalid opcode: 0000 [#1] SMP
  Modules linked in: acpihp_drv acpihp_slot edd cpufreq_conservative cpufreq_userspace cpufreq_powersave acpi_cpufreq mperf fuse vfat fat loop dm_mod coretemp kvm crc32c_intel ipv6 ixgbe igb iTCO_wdt i7core_edac edac_core pcspkr iTCO_vendor_support ioatdma microcode joydev sr_mod i2c_i801 dca lpc_ich mfd_core mdio tpm_tis i2c_core hid_generic tpm cdrom sg tpm_bios rtc_cmos button ext3 jbd mbcache usbhid hid uhci_hcd ehci_hcd usbcore usb_common sd_mod crc_t10dif processor thermal_sys hwmon scsi_dh_alua scsi_dh_hp_sw scsi_dh_rdac scsi_dh_emc scsi_dh ata_generic ata_piix libata megaraid_sas scsi_mod
  CPU 39
  Pid: 6454, comm: sh Not tainted 3.7.0-rc1-acpihp-final+ #45 QCI QSSC-S4R/QSSC-S4R
  RIP: 0010:[<ffffffff8103c908>]  [<ffffffff8103c908>] __phys_addr+0x88/0x90
  RSP: 0018:ffff8804440d7c08  EFLAGS: 00010006
  RAX: 0000000000000006 RBX: ffffea0012000000 RCX: 000000000000002c
  ...

Signed-off-by: Jianguo Wu <wujianguo@huawei.com>
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Reviewd-by: Wen Congyang <wency@cn.fujitsu.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Reviewed-by: Michal Hocko <mhocko@suse.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 58d00209

mm/sparse.c

+4 −6

Original line number	Diff line number	Diff line
		@@ -617,7 +617,7 @@ static void __kfree_section_memmap(struct page *memmap, unsigned long nr_pages)
		{
		return; /* XXX: Not implemented yet */
		}
		static void free_map_bootmem(struct page *page, unsigned long nr_pages)
		static void free_map_bootmem(struct page *memmap, unsigned long nr_pages)
		{
		}
		#else
		@@ -658,10 +658,11 @@ static void __kfree_section_memmap(struct page *memmap, unsigned long nr_pages)
		get_order(sizeof(struct page) * nr_pages));
		}

		static void free_map_bootmem(struct page *page, unsigned long nr_pages)
		static void free_map_bootmem(struct page *memmap, unsigned long nr_pages)
		{
		unsigned long maps_section_nr, removing_section_nr, i;
		unsigned long magic;
		struct page *page = virt_to_page(memmap);

		for (i = 0; i < nr_pages; i++, page++) {
		magic = (unsigned long) page->lru.next;
		@@ -710,13 +711,10 @@ static void free_section_usemap(struct page memmap, unsigned long usemap)
		*/

		if (memmap) {
		struct page *memmap_page;
		memmap_page = virt_to_page(memmap);

		nr_pages = PAGE_ALIGN(PAGES_PER_SECTION * sizeof(struct page))
		>> PAGE_SHIFT;

		free_map_bootmem(memmap_page, nr_pages);
		free_map_bootmem(memmap, nr_pages);
		}
		}