alistair23-linux/mm
Youquan Song 58a84aa927 thp: set compound tail page _count to zero
Commit 70b50f94f1 ("mm: thp: tail page refcounting fix") keeps all
page_tail->_count zero at all times.  But the current kernel does not
set page_tail->_count to zero if a 1GB page is utilized.  So when an
IOMMU 1GB page is used by KVM, it wil result in a kernel oops because a
tail page's _count does not equal zero.

  kernel BUG at include/linux/mm.h:386!
  invalid opcode: 0000 [#1] SMP
  Call Trace:
    gup_pud_range+0xb8/0x19d
    get_user_pages_fast+0xcb/0x192
    ? trace_hardirqs_off+0xd/0xf
    hva_to_pfn+0x119/0x2f2
    gfn_to_pfn_memslot+0x2c/0x2e
    kvm_iommu_map_pages+0xfd/0x1c1
    kvm_iommu_map_memslots+0x7c/0xbd
    kvm_iommu_map_guest+0xaa/0xbf
    kvm_vm_ioctl_assigned_device+0x2ef/0xa47
    kvm_vm_ioctl+0x36c/0x3a2
    do_vfs_ioctl+0x49e/0x4e4
    sys_ioctl+0x5a/0x7c
    system_call_fastpath+0x16/0x1b
  RIP  gup_huge_pud+0xf2/0x159

Signed-off-by: Youquan Song <youquan.song@intel.com>
Reviewed-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-12-09 07:50:28 -08:00
..
backing-dev.c backing-dev: ensure wakeup_timer is deleted 2011-11-11 13:29:04 +01:00
bootmem.c mm: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
bounce.c Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
cleancache.c
compaction.c mm: compaction: make compact_zone_order() static 2011-10-31 17:30:49 -07:00
debug-pagealloc.c debug-pagealloc: add support for highmem pages 2011-10-31 17:30:48 -07:00
dmapool.c mm: fix implicit stat.h usage in dmapool.c 2011-10-31 09:20:12 -04:00
fadvise.c
failslab.c fault-injection: add ability to export fault_attr in arbitrary directory 2011-08-03 14:25:20 -10:00
filemap.c mm: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
filemap_xip.c mm: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
fremap.c mm: delete various needless include <linux/module.h> 2011-10-31 09:20:11 -04:00
highmem.c Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
huge_memory.c thp: reduce khugepaged freezing latency 2011-12-09 07:50:28 -08:00
hugetlb.c thp: set compound tail page _count to zero 2011-12-09 07:50:28 -08:00
hwpoison-inject.c
init-mm.c atomic: use <linux/atomic.h> 2011-07-26 16:49:47 -07:00
internal.h mm: thp: tail page refcounting fix 2011-11-02 16:06:57 -07:00
Kconfig memblock: add NO_BOOTMEM config symbol 2011-10-31 17:30:47 -07:00
Kconfig.debug
kmemcheck.c
kmemleak-test.c
kmemleak.c mm: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
ksm.c oom: fix race while temporarily setting current's oom_score_adj 2011-10-31 17:30:45 -07:00
maccess.c mm: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
madvise.c fs: kill i_alloc_sem 2011-07-20 20:47:46 -04:00
Makefile Cross Memory Attach 2011-10-31 17:30:44 -07:00
memblock.c mm/memblock.c: quiet sparse noise 2011-10-31 17:30:50 -07:00
memcontrol.c Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
memory-failure.c Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
memory.c Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
memory_hotplug.c mm: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
mempolicy.c Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
mempool.c mm: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
migrate.c Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
mincore.c mm: clarify the radix_tree exceptional cases 2011-08-03 14:25:24 -10:00
mlock.c Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
mm_init.c mm: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
mmap.c Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
mmu_context.c mm: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
mmu_notifier.c mm: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
mmzone.c mm: delete various needless include <linux/module.h> 2011-10-31 09:20:11 -04:00
mprotect.c
mremap.c thp: mremap support and TLB optimization 2011-10-31 17:30:48 -07:00
msync.c
nobootmem.c mm: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
nommu.c xen: map foreign pages for shared rings by updating the PTEs directly 2011-11-16 12:13:08 -05:00
oom_kill.c oom: do not kill tasks with oom_score_adj OOM_SCORE_ADJ_MIN 2011-11-15 22:41:51 -02:00
page-writeback.c writeback: remove vm_dirties and task->dirties 2011-11-17 20:49:06 +08:00
page_alloc.c thp: set compound tail page _count to zero 2011-12-09 07:50:28 -08:00
page_cgroup.c mm/page_cgroup.c: quiet sparse noise 2011-11-02 16:07:00 -07:00
page_io.c
page_isolation.c
pagewalk.c pagewalk: fix code comment for THP 2011-07-25 20:57:09 -07:00
percpu-km.c
percpu-vm.c percpu: fix chunk range calculation 2011-11-22 08:09:46 -08:00
percpu.c percpu: explain why per_cpu_ptr_to_phys() is more complicated than necessary 2011-11-23 08:20:53 -08:00
pgtable-generic.c
prio_tree.c
process_vm_access.c Cross Memory Attach 2011-10-31 17:30:44 -07:00
quicklist.c mm: delete various needless include <linux/module.h> 2011-10-31 09:20:11 -04:00
readahead.c mm: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
rmap.c Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
shmem.c Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
slab.c slab, lockdep: Fix silly bug 2011-12-05 09:44:00 +01:00
slob.c mm: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
slub.c slub: avoid potential NULL dereference or corruption 2011-11-24 08:44:19 +02:00
sparse-vmemmap.c mm: delete various needless include <linux/module.h> 2011-10-31 09:20:11 -04:00
sparse.c mm: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
swap.c Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
swap_state.c mm: delete various needless include <linux/module.h> 2011-10-31 09:20:11 -04:00
swapfile.c Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
thrash.c mm/thrash.c: quiet sparse noise 2011-10-31 17:30:50 -07:00
truncate.c mm: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
util.c mm: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
vmalloc.c xen: map foreign pages for shared rings by updating the PTEs directly 2011-11-16 12:13:08 -05:00
vmscan.c vmscan: use atomic-long for shrinker batching 2011-12-09 07:50:27 -08:00
vmstat.c mm/vmstat.c: cache align vm_stat 2011-10-31 17:30:51 -07:00