The parameter's origin type is long. On an i386 architecture, it can
easily be larger than 0x80000000, causing this function to convert it to a
sign-extended u64 type. Change the type to unsigned long so we get the
correct result.
Signed-off-by: hank <pyu@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: John Stultz <john.stultz@linaro.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Julia Lawall [Sat, 16 Jul 2011 13:30:45 +0000 (23:30 +1000)]
The out_msi_disable label should be before cleanup_nomem to additionally
benefit from the call to iounmap. Subsequent gotos are adjusted to go to
out_msi_disable instead of cleanup_nomem, which now follows it. This is
safe because pci_disable_msi does nothing if pci_enable_msi was not called.
A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)
// <smpl>
@r@
expression e1,e2;
statement S;
@@
e1 = pci_ioremap_bar(...);
... when != e1 = e2
when != iounmap(e1)
when any
(
if (<+...e1...+>) S
|
if(...) { ... return 0; }
|
if (...) { ... when != iounmap(e1)
when != if (...) { ... iounmap(e1) ... }
* return ...;
} else S
)
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk> Acked-by: Brian King <brking@linux.vnet.ibm.com> Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Dan Rosenberg [Sat, 16 Jul 2011 13:30:45 +0000 (23:30 +1000)]
There's a code path in pmcraid that can be reached via device ioctl that
causes all sorts of ugliness, including heap corruption or triggering the
OOM killer due to consecutive allocation of large numbers of pages.
First, the user can call pmcraid_chr_ioctl(), with a type
PMCRAID_PASSTHROUGH_IOCTL. This calls through to
pmcraid_ioctl_passthrough(). Next, a pmcraid_passthrough_ioctl_buffer is
copied in, and the request_size variable is set to
buffer->ioarcb.data_transfer_length, which is an arbitrary 32-bit signed
value provided by the user. If a negative value is provided here, bad
things can happen. For example, pmcraid_build_passthrough_ioadls() is
called with this request_size, which immediately calls
pmcraid_alloc_sglist() with a negative size. The resulting math on
allocating a scatter list can result in an overflow in the kzalloc() call
(if num_elem is 0, the sglist will be smaller than expected), or if
num_elem is unexpectedly large the subsequent loop will call alloc_pages()
repeatedly, a high number of pages will be allocated and the OOM killer
might be invoked.
It looks like preventing this value from being negative in
pmcraid_ioctl_passthrough() would be sufficient. Something like this
might do:
Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com> Cc: Anil Ravindranath <anil_ravindranath@pmc-sierra.com> Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
WANG Cong [Sat, 16 Jul 2011 13:30:44 +0000 (23:30 +1000)]
arch/cris/arch-v10/kernel/irq.c:239: error: implicit declaration of function 'kgdb_init'
arch/cris/arch-v10/kernel/irq.c:240: error: implicit declaration of function 'breakpoint'
Declare these two functions.
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com> Cc: Mikael Starvik <starvik@axis.com> Cc: Jesper Nilsson <jesper.nilsson@axis.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Andrew Morton [Sat, 16 Jul 2011 13:30:43 +0000 (23:30 +1000)]
WARNING: line over 80 characters
#37: FILE: arch/cris/include/asm/thread_info.h:70:
+#define alloc_thread_info_node(tsk, node) ((struct thread_info *) __get_free_pages(GFP_KERNEL,1))
ERROR: space required after that ',' (ctx:VxV)
#37: FILE: arch/cris/include/asm/thread_info.h:70:
+#define alloc_thread_info_node(tsk, node) ((struct thread_info *) __get_free_pages(GFP_KERNEL,1))
^
total: 1 errors, 1 warnings, 18 lines checked
./patches/cris-fix-a-build-error-in-kernel-forkc.patch has style problems, please review. If any of these errors
are false positives report them to the maintainer, see
CHECKPATCH in MAINTAINERS.
Please run checkpatch prior to sending patches
Cc: WANG Cong <xiyou.wangcong@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Peter Zijlstra [Sat, 16 Jul 2011 13:30:42 +0000 (23:30 +1000)]
Vito said:
: The system has many usb disks coming and going day to day, with their
: respective bdi's having min_ratio set to 1 when inserted. It works for
: some time until eventually min_ratio can no longer be set, even when the
: active set of bdi's seen in /sys/class/bdi/*/min_ratio doesn't add up to
: anywhere near 100.
:
: This then leads to an unrelated starvation problem caused by write-heavy
: fuse mounts being used atop the usb disks, a problem the min_ratio setting
: at the underlying devices bdi effectively prevents.
Fix this leakage by resetting the bdi min_ratio when unregistering the
BDI.
2.6.36's 7e496299d4d2 ("tmpfs: make tmpfs scalable with percpu_counter for
used blocks") to make tmpfs scalable with percpu_counter used
inode->i_lock in place of sbinfo->stat_lock around i_blocks updates; but
that was adverse to scalability, and unnecessary, since info->lock is
already held there in the fast paths.
Remove those uses of i_lock, and add info->lock in the three error paths
where it's then needed across shmem_free_blocks(). It's not actually
needed across shmem_unacct_blocks(), but they're so often paired that it
looks wrong to split them apart.
Signed-off-by: Hugh Dickins <hughd@google.com> Acked-by: Tim Chen <tim.c.chen@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
truncate_inode_pages_range()'s final loop has a nice pincer property,
bringing start and end together, squeezing out the last pages. But the
range handling missed out on that, just sliding up the range, perhaps
letting pages come in behind it. Add one more test to give it the same
pincer effect.
Signed-off-by: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Make the pagevec_lookup loops in truncate_inode_pages_range(),
invalidate_mapping_pages() and invalidate_inode_pages2_range() more
consistent with each other.
They were relying upon page->index of an unlocked page, but apologizing
for it: accept it, embrace it, add comments and WARN_ONs, and simplify the
index handling.
invalidate_inode_pages2_range() had special handling for a wrapped
page->index + 1 = 0 case; but MAX_LFS_FILESIZE doesn't let us anywhere
near there, and a corrupt page->index in the radix_tree could cause more
trouble than that would catch. Remove that wrapped handling.
invalidate_inode_pages2_range() uses min() to limit the pagevec_lookup
when near the end of the range: copy that into the other two, although
it's less useful than you might think (it limits the use of the buffer,
rather than the indices looked up).
Signed-off-by: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Use consistent variable names in truncate_pagecache(), truncate_setsize(),
vmtruncate() and vmtruncate_range().
unmap_mapping_range() and vmtruncate_range() have mismatched interfaces:
don't change either, but make the vmtruncates more precise about what they
expect unmap_mapping_range() to do.
vmtruncate_range() is currently called only with page-aligned start and
end+1: can handle unaligned start, but unaligned end+1 would hit BUG_ON in
truncate_inode_pages_range() (lacks partial clearing of the end page).
Signed-off-by: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The often-NULL data arg to read_cache_page() and read_mapping_page()
functions is misdescribed as "destination for read data": no, it's the
first arg to the filler function, often struct file * to ->readpage().
Satisfy checkpatch.pl on those filler prototypes, and tidy up the
declarations in linux/pagemap.h.
Signed-off-by: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Currently we are keeping faulted page locked throughout whole __do_fault
call (except for page_mkwrite code path) after calling file system's fault
code. If we do early COW, we allocate a new page which has to be charged
for a memcg (mem_cgroup_newpage_charge).
This function, however, might block for unbounded amount of time if memcg
oom killer is disabled or fork-bomb is running because the only way out of
the OOM situation is either an external event or OOM-situation fix.
In the end we are keeping the faulted page locked and blocking other
processes from faulting it in which is not good at all because we are
basically punishing potentially an unrelated process for OOM condition in
a different group (I have seen stuck system because of ld-2.11.1.so being
locked).
We can do test easily.
% cgcreate -g memory:A
% cgset -r memory.limit_in_bytes=64M A
% cgset -r memory.memsw.limit_in_bytes=64M A
% cd kernel_dir; cgexec -g memory:A make -j
Then, the whole system will live-locked until you kill 'make -j'
by hands (or push reboot...) This is because some important page in a
a shared library are locked.
Considering again, the new page is not necessary to be allocated
with lock_page() held. And usual page allocation may dive into
long memory reclaim loop with holding lock_page() and can cause
very long latency.
There are 3 ways.
1. do allocation/charge before lock_page()
Pros. - simple and can handle page allocation in the same manner.
This will reduce holding time of lock_page() in general.
Cons. - we do page allocation even if ->fault() returns error.
2. do charge after unlock_page(). Even if charge fails, it's just OOM.
Pros. - no impact to non-memcg path.
Cons. - implemenation requires special cares of LRU and we need to modify
page_add_new_anon_rmap()...
3. do unlock->charge->lock again method.
Pros. - no impact to non-memcg path.
Cons. - This may kill LOCK_PAGE_RETRY optimization. We need to release
lock and get it again...
This patch moves "charge" and memory allocation for COW page
before lock_page(). Then, we can avoid scanning LRU with holding
a lock on a page and latency under lock_page() will be reduced.
Then, above livelock disappears.
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Reported-by: Lutz Vieweg <lvml@5t9.de> Original-idea-by: Michal Hocko <mhocko@suse.cz> Cc: Michal Hocko <mhocko@suse.cz> Cc: Ying Han <yinghan@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
projects / karo-tx-linux.git / log