linux-toradex.git/mm/hugetlb.c, branch v3.1.7

thp: set compound tail page _count to zero

2011-12-21T20:58:22+00:00

commit 58a84aa92723d1ac3e1cc4e3b0ff49291663f7e1 upstream.

Commit 70b50f94f1644 ("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 
Reviewed-by: Andrea Arcangeli 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

hugetlb: release pages in the error path of hugetlb_cow()

2011-12-09T16:54:31+00:00

commit ea4039a34c4c206d015d34a49d0b00868e37db1d upstream.

If we fail to prepare an anon_vma, the {new, old}_page should be released,
or they will leak.

Signed-off-by: Hillf Danton 
Reviewed-by: Andrea Arcangeli 
Cc: Hugh Dickins 
Cc: Johannes Weiner 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Cc: Michal Hocko 
Signed-off-by: Greg Kroah-Hartman

mm: hugetlb: fix coding style issues

2011-07-26T03:57:09+00:00

Fix coding style issues flagged by checkpatch.pl

Signed-off-by: Chris Forbes 
Acked-by: Eric B Munson 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

hugetlb: add phys addr to struct huge_bootmem_page

2011-07-26T03:57:07+00:00

This is needed on HIGHMEM systems - we don't always have a virtual
address so store the physical address and map it in as needed.

[akpm@linux-foundation.org: cleanup]
Signed-off-by: Becky Bruce 
Cc: Benjamin Herrenschmidt 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: fix negative commitlimit when gigantic hugepages are allocated

2011-06-16T03:04:01+00:00

When 1GB hugepages are allocated on a system, free(1) reports less
available memory than what really is installed in the box.  Also, if the
total size of hugepages allocated on a system is over half of the total
memory size, CommitLimit becomes a negative number.

The problem is that gigantic hugepages (order > MAX_ORDER) can only be
allocated at boot with bootmem, thus its frames are not accounted to
'totalram_pages'.  However, they are accounted to hugetlb_total_pages()

What happens to turn CommitLimit into a negative number is this
calculation, in fs/proc/meminfo.c:

        allowed = ((totalram_pages - hugetlb_total_pages())
                * sysctl_overcommit_ratio / 100) + total_swap_pages;

A similar calculation occurs in __vm_enough_memory() in mm/mmap.c.

Also, every vm statistic which depends on 'totalram_pages' will render
confusing values, as if system were 'missing' some part of its memory.

Impact of this bug:

When gigantic hugepages are allocated and sysctl_overcommit_memory ==
OVERCOMMIT_NEVER.  In a such situation, __vm_enough_memory() goes through
the mentioned 'allowed' calculation and might end up mistakenly returning
-ENOMEM, thus forcing the system to start reclaiming pages earlier than it
would be ususal, and this could cause detrimental impact to overall
system's performance, depending on the workload.

Besides the aforementioned scenario, I can only think of this causing
annoyances with memory reports from /proc/meminfo and free(1).

[akpm@linux-foundation.org: standardize comment layout]
Reported-by: Russ Anderson 
Signed-off-by: Rafael Aquini 
Acked-by: Russ Anderson 
Cc: Andrea Arcangeli 
Cc: Christoph Lameter 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: fix ENOSPC returned by handle_mm_fault()

2011-06-06T09:00:27+00:00

Al Viro observes that in the hugetlb case, handle_mm_fault() may return
a value of the kind ENOSPC when its caller is expecting a value of the
kind VM_FAULT_SIGBUS: fix alloc_huge_page()'s failure returns.

Signed-off-by: Hugh Dickins 
Acked-by: Al Viro 
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds

mm: don't access vm_flags as 'int'

2011-05-26T16:20:31+00:00

The type of vma->vm_flags is 'unsigned long'. Neither 'int' nor
'unsigned int'. This patch fixes such misuse.

Signed-off-by: KOSAKI Motohiro 
[ Changed to use a typedef - we'll extend it to cover more cases
  later, since there has been discussion about making it a 64-bit
  type..                      - Linus ]
Signed-off-by: Linus Torvalds

mm: Convert i_mmap_lock to a mutex

2011-05-25T15:39:18+00:00

Straightforward conversion of i_mmap_lock to a mutex.

Signed-off-by: Peter Zijlstra 
Acked-by: Hugh Dickins 
Cc: Benjamin Herrenschmidt 
Cc: David Miller 
Cc: Martin Schwidefsky 
Cc: Russell King 
Cc: Paul Mundt 
Cc: Jeff Dike 
Cc: Richard Weinberger 
Cc: Tony Luck 
Cc: KAMEZAWA Hiroyuki 
Cc: Mel Gorman 
Cc: KOSAKI Motohiro 
Cc: Nick Piggin 
Cc: Namhyung Kim 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Merge branch 'master' into for-next

2011-04-26T08:22:59+00:00

Fast-forwarded to current state of Linus' tree as there are patches to be
applied for files that didn't exist on the old branch.

treewide: remove extra semicolons

2011-04-10T15:01:05+00:00

Signed-off-by: Justin P. Mattock 
Signed-off-by: Jiri Kosina