linux/arch/x86/mm
Toshi Kani d9fe4fab11 x86/mm/pat: Add untrack_pfn_moved for mremap
mremap() with MREMAP_FIXED on a VM_PFNMAP range causes the following
WARN_ON_ONCE() message in untrack_pfn().

  WARNING: CPU: 1 PID: 3493 at arch/x86/mm/pat.c:985 untrack_pfn+0xbd/0xd0()
  Call Trace:
  [<ffffffff817729ea>] dump_stack+0x45/0x57
  [<ffffffff8109e4b6>] warn_slowpath_common+0x86/0xc0
  [<ffffffff8109e5ea>] warn_slowpath_null+0x1a/0x20
  [<ffffffff8106a88d>] untrack_pfn+0xbd/0xd0
  [<ffffffff811d2d5e>] unmap_single_vma+0x80e/0x860
  [<ffffffff811d3725>] unmap_vmas+0x55/0xb0
  [<ffffffff811d916c>] unmap_region+0xac/0x120
  [<ffffffff811db86a>] do_munmap+0x28a/0x460
  [<ffffffff811dec33>] move_vma+0x1b3/0x2e0
  [<ffffffff811df113>] SyS_mremap+0x3b3/0x510
  [<ffffffff817793ee>] entry_SYSCALL_64_fastpath+0x12/0x71

MREMAP_FIXED moves a pfnmap from old vma to new vma.  untrack_pfn() is
called with the old vma after its pfnmap page table has been removed,
which causes follow_phys() to fail.  The new vma has a new pfnmap to
the same pfn & cache type with VM_PAT set.  Therefore, we only need to
clear VM_PAT from the old vma in this case.

Add untrack_pfn_moved(), which clears VM_PAT from a given old vma.
move_vma() is changed to call this function with the old vma when
VM_PFNMAP is set.  move_vma() then calls do_munmap(), and untrack_pfn()
is a no-op since VM_PAT is cleared.

Reported-by: Stas Sergeev <stsp@list.ru>
Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/1450832064-10093-2-git-send-email-toshi.kani@hpe.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-01-05 11:10:05 +01:00
..
kmemcheck x86: Replace __get_cpu_var uses 2014-08-26 13:45:49 -04:00
Makefile x86/mm: Turn CONFIG_X86_PTDUMP into a module 2015-11-23 10:50:13 +01:00
amdtopology.c x86/mm/numa: Simplify some bit mangling 2013-04-10 19:06:26 +02:00
debug_pagetables.c x86/mm/ptdump: Make (debugfs)/kernel_page_tables read-only 2015-12-04 12:55:01 +01:00
dump_pagetables.c x86/mm: Turn CONFIG_X86_PTDUMP into a module 2015-11-23 10:50:13 +01:00
extable.c x86, extable: Switch to relative exception table entries 2012-04-20 17:22:34 -07:00
fault.c x86/vm86: Clean up vm86.h includes 2015-07-31 13:31:10 +02:00
gup.c x86/mm: Fix gup_huge_p?d() to handle large PAT bit 2015-09-22 21:27:33 +02:00
highmem_32.c kmap_atomic_to_page() has no users, remove it 2015-11-09 15:11:24 -08:00
hugetlbpage.c mm/hugetlb: pmd_huge() returns true for non-present hugepage 2015-02-11 17:06:01 -08:00
init.c libnvdimm for 4.4: 2015-11-10 12:07:22 -08:00
init_32.c x86/mm: Warn on W^X mappings 2015-10-06 11:11:48 +02:00
init_64.c libnvdimm for 4.4: 2015-11-10 12:07:22 -08:00
iomap_32.c Merge branch 'x86-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-06-22 17:59:09 -07:00
ioremap.c x86/mm: Drop WARN from multi-BAR check 2015-12-29 12:34:38 +01:00
kasan_init_64.c kasan: update log messages 2015-11-05 19:34:48 -08:00
kmmio.c x86: Delete non-required instances of include <linux/init.h> 2014-01-06 21:25:18 -08:00
mm_internal.h x86: Enable PAT to use cache mode translation tables 2014-11-16 11:04:26 +01:00
mmap.c x86/mpx: Do not set ->vm_ops on MPX VMAs 2015-07-21 07:57:16 +02:00
mmio-mod.c x86: delete __cpuinit usage from all x86 files 2013-07-14 19:36:56 -04:00
mpx.c x86/mpx: Fix 32-bit address space calculation 2015-11-12 09:20:37 +01:00
numa.c mem-hotplug: handle node hole when initializing numa_meminfo. 2015-09-08 15:35:28 -07:00
numa_32.c x86: Fix the initialization of physnode_map 2014-02-01 22:15:51 -08:00
numa_64.c x86, mm: kill numa_free_all_bootmem() 2012-11-17 11:59:47 -08:00
numa_emulation.c x86: delete __cpuinit usage from all x86 files 2013-07-14 19:36:56 -04:00
numa_internal.h x86-32, mm: Rip out x86_32 NUMA remapping code 2013-01-31 14:12:30 -08:00
pageattr-test.c x86/mm/pat: Make mm/pageattr[-test].c explicitly non-modular 2015-08-25 09:48:38 +02:00
pageattr.c Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-11-03 21:23:56 -08:00
pat.c x86/mm/pat: Add untrack_pfn_moved for mremap 2016-01-05 11:10:05 +01:00
pat_internal.h x86/mm/pat: Convert to pr_*() usage 2015-05-27 14:40:59 +02:00
pat_rbtree.c x86/mm/pat: Convert to pr_*() usage 2015-05-27 14:40:59 +02:00
pf_in.c x86: Eliminate various 'set but not used' warnings 2011-05-21 19:10:33 +02:00
pf_in.h
pgtable.c x86/mm/mtrr: Enhance MTRR checks in kernel mapping helpers 2015-05-27 14:40:58 +02:00
pgtable_32.c x86: Remove set_pmd_pfn 2014-09-01 10:15:31 +02:00
physaddr.c x86, mm: Make DEBUG_VIRTUAL work earlier in boot 2013-01-25 16:33:22 -08:00
physaddr.h x86: split __phys_addr out into separate file 2009-09-10 11:48:55 -07:00
setup_nx.c x86: delete __cpuinit usage from all x86 files 2013-07-14 19:36:56 -04:00
srat.c x86/mm: Introduce max_possible_pfn 2015-12-06 12:46:31 +01:00
testmmiotrace.c x86, kmmio/mmiotrace: Fix double free of kmmio_fault_pages 2010-06-18 11:30:09 +02:00
tlb.c x86, mm: trace when an IPI is about to be sent 2015-09-04 16:54:41 -07:00