linux/mm
Cliff Wickman a9ff785e44 mm/pagewalk.c: walk_page_range should avoid VM_PFNMAP areas
A panic can be caused by simply cat'ing /proc/<pid>/smaps while an
application has a VM_PFNMAP range.  It happened in-house when a
benchmarker was trying to decipher the memory layout of his program.

/proc/<pid>/smaps and similar walks through a user page table should not
be looking at VM_PFNMAP areas.

Certain tests in walk_page_range() (specifically split_huge_page_pmd())
assume that all the mapped PFN's are backed with page structures.  And
this is not usually true for VM_PFNMAP areas.  This can result in panics
on kernel page faults when attempting to address those page structures.

There are a half dozen callers of walk_page_range() that walk through a
task's entire page table (as N.  Horiguchi pointed out).  So rather than
change all of them, this patch changes just walk_page_range() to ignore
VM_PFNMAP areas.

The logic of hugetlb_vma() is moved back into walk_page_range(), as we
want to test any vma in the range.

VM_PFNMAP areas are used by:
- graphics memory manager   gpu/drm/drm_gem.c
- global reference unit     sgi-gru/grufile.c
- sgi special memory        char/mspec.c
- and probably several out-of-tree modules

[akpm@linux-foundation.org: remove now-unused hugetlb_vma() stub]
Signed-off-by: Cliff Wickman <cpw@sgi.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: David Sterba <dsterba@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: KOSAKI Motohiro <kosaki.motohiro@gmail.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-24 16:22:53 -07:00
..
Kconfig mmKconfig: add an option to disable bounce 2013-04-29 15:54:40 -07:00
Kconfig.debug
Makefile memcg: add memory.pressure_level events 2013-04-29 15:54:38 -07:00
backing-dev.c writeback: expose the bdi_wq workqueue 2013-04-01 19:08:06 -07:00
balloon_compaction.c mm: introduce a common interface for balloon pages mobility 2012-12-11 17:22:26 -08:00
bootmem.c mm: Add alloc_bootmem_low_pages_nopanic() 2013-01-29 19:32:59 -08:00
bounce.c Merge branch 'for-3.10/core' of git://git.kernel.dk/linux-block 2013-05-08 10:13:35 -07:00
cleancache.c mm: cleancache: clean up cleancache_enabled 2013-04-30 17:04:01 -07:00
compaction.c mm: add & use zone_end_pfn() and zone_spans_pfn() 2013-02-23 17:50:20 -08:00
debug-pagealloc.c
dmapool.c dmapool: make DMAPOOL_DEBUG detect corruption of free marker 2012-12-11 17:22:24 -08:00
fadvise.c teach SYSCALL_DEFINE<n> how to deal with long long/unsigned long long 2013-03-03 22:46:22 -05:00
failslab.c
filemap.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2013-05-01 17:51:54 -07:00
filemap_xip.c lift sb_start_write() out of ->write() 2013-04-09 14:12:56 -04:00
fremap.c Revert "mm: introduce VM_POPULATE flag to better deal with racy userspace programs" 2013-03-28 17:45:51 -07:00
frontswap.c frontswap: get rid of swap_lock dependency 2013-04-30 17:04:00 -07:00
highmem.c Some nice cleanups, and even a patch my wife did as a "live" demo for 2012-12-20 08:37:05 -08:00
huge_memory.c mm/THP: use pmd_populate() to update the pmd with pgtable_t pointer 2013-05-24 16:22:51 -07:00
hugetlb.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2013-04-30 09:36:50 -07:00
hugetlb_cgroup.c mm/hugetlb: create hugetlb cgroup file in hugetlb_init 2012-12-18 15:02:15 -08:00
hwpoison-inject.c
init-mm.c
internal.h mm: accelerate munlock() treatment of THP pages 2013-02-27 19:10:09 -08:00
interval_tree.c
kmemcheck.c
kmemleak-test.c
kmemleak.c hlist: drop the node parameter from iterators 2013-02-27 19:10:24 -08:00
ksm.c ksm: fix m68k build: only NUMA needs pfn_to_nid 2013-03-08 15:05:34 -08:00
maccess.c
madvise.c mm: madvise: complete input validation before taking lock 2013-04-29 15:54:37 -07:00
memblock.c memblock: fix missing comment of memblock_insert_region() 2013-04-29 15:54:38 -07:00
memcontrol.c mm: memcg: remove incorrect VM_BUG_ON for swap cache pages in uncharge 2013-05-24 16:22:51 -07:00
memory-failure.c HWPOISON: check dirty flag to match against clean page 2013-04-29 15:54:28 -07:00
memory.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2013-04-30 09:36:50 -07:00
memory_hotplug.c mm/memory_hotplug.c: fix printk format warnings 2013-05-24 16:22:52 -07:00
mempolicy.c mm/mempolicy.c: fix sp_node_init() argument ordering 2013-03-08 15:05:34 -08:00
mempool.c
migrate.c mm compaction: fix of improper cache flush in migration code 2013-05-24 16:22:51 -07:00
mincore.c swap: make each swap partition have one address_space 2013-02-23 17:50:17 -08:00
mlock.c Revert "mm: introduce VM_POPULATE flag to better deal with racy userspace programs" 2013-03-28 17:45:51 -07:00
mm_init.c mm: init: report on last-nid information stored in page->flags 2013-02-23 17:50:18 -08:00
mmap.c shm: fix null pointer deref when userspace specifies invalid hugepage size 2013-05-09 14:22:47 -07:00
mmu_context.c mm: remove old aio use_mm() comment 2013-05-07 18:38:27 -07:00
mmu_notifier.c mm: mmu_notifier: re-fix freed page still mapped in secondary MMU 2013-05-24 16:22:51 -07:00
mmzone.c mm: rename page struct field helpers 2013-02-23 17:50:18 -08:00
mprotect.c mm/mprotect.c: coding-style cleanups 2012-12-18 15:02:15 -08:00
mremap.c mm/rmap: rename anon_vma_unlock() => anon_vma_unlock_write() 2013-02-23 17:50:17 -08:00
msync.c
nobootmem.c mm, nobootmem: do memset() after memblock_reserve() 2013-04-29 15:54:39 -07:00
nommu.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal 2013-05-01 07:21:43 -07:00
oom_kill.c memcg, oom: provide more precise dump info while memcg oom happening 2013-02-23 17:50:08 -08:00
page-writeback.c mm: make snapshotting pages for stable writes a per-bio operation 2013-04-29 15:54:33 -07:00
page_alloc.c mm: Fix virt_to_page() warning 2013-05-22 08:05:16 -07:00
page_cgroup.c memcontrol: use N_MEMORY instead N_HIGH_MEMORY 2012-12-12 17:38:32 -08:00
page_io.c Merge branch 'for-3.10/core' of git://git.kernel.dk/linux-block 2013-05-08 10:13:35 -07:00
page_isolation.c mm: fix zone_watermark_ok_safe() accounting of isolated pages 2013-01-04 16:11:46 -08:00
pagewalk.c mm/pagewalk.c: walk_page_range should avoid VM_PFNMAP areas 2013-05-24 16:22:53 -07:00
percpu-km.c
percpu-vm.c
percpu.c mm, percpu: Make sure percpu_alloc early parameter has an argument 2012-12-02 06:23:04 -08:00
pgtable-generic.c mm: Only flush the TLB when clearing an accessible pte 2012-12-11 14:28:34 +00:00
process_vm_access.c Fix: compat_rw_copy_check_uvector() misuse in aio, readv, writev, and security keys 2013-03-12 11:05:45 -07:00
quicklist.c
readahead.c teach SYSCALL_DEFINE<n> how to deal with long long/unsigned long long 2013-03-03 22:46:22 -05:00
rmap.c rmap: recompute pgoff for unmapping huge page 2013-04-29 15:54:28 -07:00
shmem.c aio: don't include aio.h in sched.h 2013-05-07 20:16:25 -07:00
slab.c Merge branch 'slab/for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/linux 2013-05-07 08:42:20 -07:00
slab.h slab: Common definition for kmem_cache_node 2013-02-01 12:32:09 +02:00
slab_common.c mm/slab: Fix crash during slab init 2013-05-08 15:02:33 -07:00
slob.c mm: rename page struct field helpers 2013-02-23 17:50:18 -08:00
slub.c Merge branch 'slab/for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/linux 2013-05-07 08:42:20 -07:00
sparse-vmemmap.c sparse-vmemmap: specify vmemmap population range in bytes 2013-04-29 15:54:35 -07:00
sparse.c mm, hotplug: avoid compiling memory hotremove functions when disabled 2013-04-29 15:54:37 -07:00
swap.c aio: don't include aio.h in sched.h 2013-05-07 20:16:25 -07:00
swap_state.c mm: thp: add split tail pages to shrink page list in page reclaim 2013-04-29 15:54:38 -07:00
swapfile.c frontswap: get rid of swap_lock dependency 2013-04-30 17:04:00 -07:00
truncate.c mm: drop vmtruncate 2012-12-20 18:46:29 -05:00
util.c swap: make each swap partition have one address_space 2013-02-23 17:50:17 -08:00
vmalloc.c mm/vmalloc.c: add vfree comment 2013-05-07 18:38:27 -07:00
vmpressure.c memcg: add memory.pressure_level events 2013-04-29 15:54:38 -07:00
vmscan.c mm: thp: add split tail pages to shrink page list in page reclaim 2013-04-29 15:54:38 -07:00
vmstat.c mm/vmstat: add note on safety of drain_zonestat 2013-04-29 15:54:38 -07:00