linux/include
Wu Fengguang 3310225dfc lib: proportion: lower PROP_MAX_SHIFT to 32 on 64-bit kernel
PROP_MAX_SHIFT should be set to <=32 on 64-bit box. This fixes two bugs
in the below lines of bdi_dirty_limit():

	bdi_dirty *= numerator;
	do_div(bdi_dirty, denominator);

1) divide error: do_div() only uses the lower 32 bit of the denominator,
   which may trimmed to be 0 when PROP_MAX_SHIFT > 32.

2) overflow: (bdi_dirty * numerator) could easily overflow if numerator
   used up to 48 bits, leaving only 16 bits to bdi_dirty

Cc: <stable@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reported-by: Ilya Tumaykin <librarian_rus@yahoo.com>
Tested-by: Ilya Tumaykin <librarian_rus@yahoo.com>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2012-02-01 16:53:46 +08:00
..
acpi Merge branches 'atomicio-apei', 'hotplug', 'sony-nvs-nosave' and 'thermal-netlink' into release 2012-01-23 19:47:06 -05:00
asm-generic Merge branch 'for-next' of git://git.infradead.org/users/dhowells/linux-headers 2012-01-14 18:03:30 -08:00
crypto
drm drm: Fix authentication kernel crash 2012-01-25 09:27:45 +00:00
keys keys: add a "logon" key type 2012-01-17 22:39:40 -06:00
linux lib: proportion: lower PROP_MAX_SHIFT to 32 on 64-bit kernel 2012-02-01 16:53:46 +08:00
math-emu
media Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media 2012-01-18 12:53:54 -08:00
misc
mtd mtd: document that MEMWRITE ioctl is NAND-specific 2012-01-09 18:18:36 +00:00
net net/tcp: Fix tcp memory limits initialization when !CONFIG_SYSCTL 2012-01-30 12:41:06 -05:00
pcmcia
rdma rdma/core: Fix sparse warnings 2012-01-04 09:17:45 -08:00
rxrpc
scsi [SCSI] libfc: Declare local functions static 2012-01-16 12:45:48 +04:00
sound Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound 2012-01-12 08:00:30 -08:00
target target: Set additional sense length field in sense data 2011-12-16 06:29:04 +00:00
trace writeback: fix NULL bdi->dev in trace writeback_single_inode 2012-02-01 16:53:40 +08:00
video Merge branch 'for-next' of git://git.infradead.org/users/dhowells/linux-headers 2012-01-14 18:03:30 -08:00
xen Merge branch 'for-3.3/drivers' of git://git.kernel.dk/linux-block 2012-01-15 12:48:41 -08:00
Kbuild