Francisco Jerez [Mon, 20 Sep 2010 14:18:28 +0000 (16:18 +0200)]
drm/nouveau: Parse old style perf tables.
Used on nv17-nv28, they contain memory clocks and timings, only one of
the table entries can actually be used, depending on the RAMCFG
straps, and it's usually higher than the frequency programmed on boot
by the BIOS.
The memory timings listed in table version 0x1x are used to init the
0x12xx range but they aren't required for reclocking to work.
Signed-off-by: Francisco Jerez <currojerez@riseup.net> Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com> Acked-by: Matthew Garrett <mjg@redhat.com>
It doesn't seem to revert cleanly, but the problem lies in these
two config entries:
CONFIG_ACPI=y
CONFIG_ACPI_VIDEO=m
Adding a select for ACPI_VIDEO appears to be the best solution, and
is comparable to what is done in DRM_I915. Builds, boots, and appears to
work correctly.
Signed-off-by: Philip J. Turmel <philip@turmel.org> Signed-off-by: Francisco Jerez <currojerez@riseup.net> Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Ben Skeggs [Thu, 16 Sep 2010 05:25:25 +0000 (15:25 +1000)]
drm/nouveau: make the behaviour of get_pll_limits() consistent
This replaces all the pll_types definitions for ones that match the types
used in the tables in recent VBIOS versions.
get_pll_limits() will now accept either type or register value as input
across all limits table versions, and will store the actual register ID
that a PLL type refers to in the returned structure.
Ben Skeggs [Wed, 8 Sep 2010 05:40:30 +0000 (15:40 +1000)]
drm/nouveau: handle fifo pusher errors better
The most important part of this change is that we now instruct PFIFO to
drop all pending fetches, rather than attempting to skip a single dword
and hope that things would magically sort themselves out - they usually
don't, and we end up with PFIFO being completely hung.
This commit also adds somewhat more useful logging when these exceptions
occur.
Francisco Jerez [Tue, 7 Sep 2010 16:24:52 +0000 (18:24 +0200)]
drm/nouveau: Simplify tile region handling.
Instead of emptying the caches to avoid a race with the PFIFO puller,
go straight ahead and try to recover from it when it happens. Also,
kill pfifo->cache_flush and tile->lock, we don't need them anymore.
Signed-off-by: Francisco Jerez <currojerez@riseup.net> Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Ben Skeggs [Fri, 3 Sep 2010 00:25:02 +0000 (10:25 +1000)]
drm/nouveau: protect ramht_find() from oopsing if on channel without ramht
This doesn't actually happen now, but there's a test case for an earlier
kernel where a GPU error is signalled on one of nv50's fake channels, and
the ramht lookup by the IRQ handler triggered an oops.
This adds a check for RAMHT's existance on a channel before looking up
an object handle.
Francisco Jerez [Mon, 30 Aug 2010 13:37:57 +0000 (15:37 +0200)]
drm/nv17-nv4x: Fix analog load detection false positive on rare occasions.
On some boards the residual current DAC outputs can draw when they're
disconnected can be high enough to give a false load detection
positive (I've only seen it in the S-video luma output of some cards,
but just to be sure). The output line capacitance is limited and
sampling twice should fix it reliably.
Signed-off-by: Francisco Jerez <currojerez@riseup.net> Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Francisco Jerez [Thu, 26 Aug 2010 21:07:02 +0000 (23:07 +0200)]
drm/nv20: Use the nv30 CRTC bandwidth calculation code.
nv2x CRTC FIFOs are as large as in nv3x (4kB it seems), and the FIFO
control registers have the same layout: we can make them share the
same implementation.
Previously we were using the nv1x code, but the calculated FIFO
watermarks are usually too low for nv2x and they cause horrible
scanout artifacts. They've gone unnoticed until now because we've been
leaving one of the bandwidth regs uninitialized (CRE 47, which
contains the most significant bits of FFLWM), so everything seemed to
work fine except in some cases after a cold boot, depending on the
memory bandwidth and pixel clocks used.
Signed-off-by: Francisco Jerez <currojerez@riseup.net> Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Francisco Jerez [Thu, 26 Aug 2010 14:13:49 +0000 (16:13 +0200)]
drm/nouveau: Fix suspend on some nv4x AGP cards.
On some nv4x cards (specifically, the ones that use an internal
PCIE->AGP bridge) the AGP controller state isn't preserved after a
suspend/resume cycle, and the AGP control registers have moved from
0x18xx to 0x100xx, so the FW check in nouveau_mem_reset_agp() doesn't
quite work. Check "dev->agp->mode" instead.
Signed-off-by: Francisco Jerez <currojerez@riseup.net> Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
hugetlb, rmap: fix confusing page locking in hugetlb_cow()
The "if (!trylock_page)" block in the avoidcopy path of hugetlb_cow()
looks confusing and is buggy. Originally this trylock_page() was
intended to make sure that old_page is locked even when old_page !=
pagecache_page, because then only pagecache_page is locked.
This patch fixes it by moving page locking into hugetlb_fault().
Change the code so that it will use the correct size for keymap entries.
Do it in a way that makes it harder to screw it up in the future.
Reported-by: Jaime Velasco Juan <jsagarribay@gmail.com> Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br> Signed-off-by: Matthew Garrett <mjg@redhat.com>
Change MSI LAPTOP driver maintainer to Lee, Chun-Yi
Change MSI LAPTOP driver maintainer from Lennart Poettering to Lee, Chun-Yi.
MSI is a Taiwan OEM company, Lee, Chun-Yi can more easy to contact with MSI
and maintain msi-laptop driver.
Thank's for Lennart Poettering's contribute, Lee, Chun-Yi will base on his
article to continue maintain the msi-laptop driver.
Signed-off-by: Lee, Chun-Yi <jlee@novell.com> Signed-off-by: Matthew Garrett <mjg@redhat.com>
Avi Kivity [Tue, 21 Sep 2010 17:59:43 +0000 (19:59 +0200)]
KVM: Fix reboot on Intel hosts
When we reboot, we disable vmx extensions or otherwise INIT gets blocked.
If a task on another cpu hits a vmx instruction, it will fault if vmx is
disabled. We trap that to avoid a nasty oops and spin until the reboot
completes.
Problem is, we sleep with interrupts disabled. This blocks smp_send_stop()
from running, and the reboot process halts.
Fix by enabling interrupts before spinning.
KVM-Stable-Tag. Signed-off-by: Avi Kivity <avi@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
During irqfd assign, we drop irqfds lock before we
schedule inject work. Therefore, deassign running
on another CPU could cause shutdown and flush to run
before inject, causing user after free in inject.
A simple fix it to schedule inject under the lock.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Gregory Haskins <ghaskins@novell.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Andrea Arcangeli [Wed, 22 Sep 2010 20:05:12 +0000 (13:05 -0700)]
mmap: call unlink_anon_vmas() in __split_vma() in case of error
If __split_vma fails because of an out of memory condition the
anon_vma_chain isn't teardown and freed potentially leading to rmap walks
accessing freed vma information plus there's a memleak.
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Acked-by: Johannes Weiner <jweiner@redhat.com> Acked-by: Rik van Riel <riel@redhat.com> Acked-by: Hugh Dickins <hughd@google.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andrea Arcangeli [Wed, 22 Sep 2010 20:05:12 +0000 (13:05 -0700)]
rmap: fix walk during fork
The below bug in fork led to the rmap walk finding the parent huge-pmd
twice instead of just once, because the anon_vma_chain objects of the
child vma still point to the vma->vm_mm of the parent.
The patch fixes it by making the rmap walk accurate during fork. It's not
a big deal normally but it worth being accurate considering the cost is
the same.
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Acked-by: Johannes Weiner <jweiner@redhat.com> Acked-by: Rik van Riel <riel@redhat.com> Acked-by: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andrew Morton [Wed, 22 Sep 2010 20:05:11 +0000 (13:05 -0700)]
drivers/pci/intel-iommu.c: fix build with older gcc's
drivers/pci/intel-iommu.c: In function `__iommu_calculate_agaw':
drivers/pci/intel-iommu.c:437: sorry, unimplemented: inlining failed in call to 'width_to_agaw': function body not available
drivers/pci/intel-iommu.c:445: sorry, unimplemented: called from here
Move the offending function (and its siblings) to top-of-file, remove the
forward declaration.
David Rientjes [Wed, 22 Sep 2010 20:05:10 +0000 (13:05 -0700)]
oom: filter unkillable tasks from tasklist dump
/proc/sys/vm/oom_dump_tasks is enabled by default, so it's necessary to
limit as much information as possible that it should emit.
The tasklist dump should be filtered to only those tasks that are eligible
for oom kill. This is already done for memcg ooms, but this patch extends
it to both cpuset and mempolicy ooms as well as init.
In addition to suppressing irrelevant information, this also reduces
confusion since users currently don't know which tasks in the tasklist
aren't eligible for kill (such as those attached to cpusets or bound to
mempolicies with a disjoint set of mems or nodes, respectively) since that
information is not shown.
Signed-off-by: David Rientjes <rientjes@google.com> Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The FBIOGET_VBLANK device ioctl allows unprivileged users to read 16 bytes
of uninitialized stack memory, because the "reserved" member of the
fb_vblank struct declared on the stack is not altered or zeroed before
being copied back to the user. This patch takes care of it.
Signed-off-by: Dan Rosenberg <dan.j.rosenberg@gmail.com> Cc: Thomas Winischhofer <thomas@winischhofer.net> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This fixes:
incompatible pointer type: => 89
arch/um/kernel/exec.c: warning: passing argument 2 of 'execve1' from
incompatible pointer type: => 69, 85
arch/um/kernel/exec.c: warning: passing argument 3 of 'execve1' from
incompatible pointer type: => 69, 85
which was introduced by d7627467b7a8d ("Make do_execve() take a const
filename pointer")
Signed-off-by: Richard Weinberger <richard@nod.at> Cc: David Howells <dhowells@redhat.com> Cc: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently, /proc/<pid>/smaps has wrong dirty pages accounting.
Shared_Dirty and Private_Dirty output only pte dirty pages and ignore
PG_dirty page flag. It is difference against documentation, but also
inconsistent against Referenced field. (Referenced checks both pte and
page flags)
The warning is caused by trying to cancel an uninitialized work from
fbcon_exit(). Fix it by adding a check for queue.func, similarly to other
places in this code.
Luke Macken [Wed, 22 Sep 2010 20:05:04 +0000 (13:05 -0700)]
efifb: support the EFI framebuffer on more Apple hardware
Enable the EFI framebuffer on 14 more Macs, including the iMac11,1
iMac10,1 iMac8,1 Macmini3,1 Macmini4,1 MacBook5,1 MacBook6,1 MacBook7,1
MacBookPro2,2 MacBookPro5,2 MacBookPro5,3 MacBookPro6,1 MacBookPro6,2 and
MacBookPro7,1
Information gathered from various user submissions.
[akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Luke Macken <lmacken@redhat.com> Signed-off-by: Peter Jones <pjones@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Peter Jones [Wed, 22 Sep 2010 20:05:04 +0000 (13:05 -0700)]
efifb: check that the base address is plausible on pci systems
Some Apple machines have identical DMI data but different memory
configurations for the video. Given that, check that the address in our
table is actually within the range of a PCI BAR on a VGA device in the
machine.
This also fixes up the return value from set_system(), which has always
been wrong, but never resulted in bad behavior since there's only ever
been one matching entry in the dmi table.
The patch
1) stops people's machines from crashing when we get their display wrong,
which seems to be unfortunately inevitable,
2) allows us to support identical dmi data with differing video memory
configurations
This also adds me as the efifb maintainer, since I've effectively been
acting as such for quite some time.
Signed-off-by: Peter Jones <pjones@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jan Kara [Wed, 22 Sep 2010 20:05:03 +0000 (13:05 -0700)]
aio: do not return ERESTARTSYS as a result of AIO
OCFS2 can return ERESTARTSYS from its write function when the process is
signalled while waiting for a cluster lock (and the filesystem is mounted
with intr mount option). Generally, it seems reasonable to allow
filesystems to return this error code from its IO functions. As we must
not leak ERESTARTSYS (and similar error codes) to userspace as a result of
an AIO operation, we have to properly convert it to EINTR inside AIO code
(restarting the syscall isn't really an option because other AIO could
have been already submitted by the same io_submit syscall).
Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Zach Brown <zach.brown@oracle.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Minchan Kim [Wed, 22 Sep 2010 20:05:01 +0000 (13:05 -0700)]
vmscan: check all_unreclaimable in direct reclaim path
M. Vefa Bicakci reported 2.6.35 kernel hang up when hibernation on his
32bit 3GB mem machine.
(https://bugzilla.kernel.org/show_bug.cgi?id=16771). Also he bisected
the regression to
vmscan: fix do_try_to_free_pages() return value when priority==0 reclaim failure
At first impression, this seemed very strange because the above commit
only chenged function return value and hibernate_preallocate_memory()
ignore return value of shrink_all_memory(). But it's related.
Now, page allocation from hibernation code may enter infinite loop if the
system has highmem. The reasons are that vmscan don't care enough OOM
case when oom_killer_disabled.
If kswapd is not freozen, it would set zone->all_unreclaimable to 1 and
then shrink_zones maybe return true(ie, all_unreclaimable is true). So at
last, alloc_pages could go to _nopage_. If it is, it should have no
problem.
This patch adds all_unreclaimable check to protect in direct reclaim path,
too. It can care of hibernation OOM case and help bailout
all_unreclaimable case slightly.
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Minchan Kim <minchan.kim@gmail.com> Reported-by: M. Vefa Bicakci <bicave@superonline.com> Reported-by: <caiqian@redhat.com> Reviewed-by: Johannes Weiner <hannes@cmpxchg.org> Tested-by: <caiqian@redhat.com> Acked-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Rik van Riel <riel@redhat.com> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Alter the maintainer of the AVR32 architecture and the AVR32/AT32AP
machine support to me. Haavard is moving on to new challenges, and we've
found it better to transfer the maintainer part to me. I will have good
contact with Haavard anyway.
In an effort to minimize customer confusion we want to unify naming
convention for VMware-provided kernel modules. This change renames the
balloon driver from vmware_ballon to vmw_balloon.
We expect to follow this naming convention (vmw_<module_name>) for all
modules that are part of mainline kernel and/or being distributed by
VMware, with the sole exception of vmxnet3 driver (since the name of
mainline driver happens to match with the name used in VMware Tools).
arm: fix "arm: fix pci_set_consistent_dma_mask for dmabounce devices"
This fixes the regression caused by the commit 6fee48cd330c68
("dma-mapping: arm: use generic pci_set_dma_mask and
pci_set_consistent_dma_mask").
ARM needs to clip the dma coherent mask for dmabounce devices. This
restores the old trick.
Note that strictly speaking, the DMA API doesn't allow architectures to do
such but I'm not sure it's worth adding the new API to set the dma mask
that allows architectures to clip it.
Reported-by: Krzysztof Halasa <khc@pm.waw.pl> Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 73296bc611 ("procfs: Use generic_file_llseek in /proc/vmcore")
broke seeking on /proc/vmcore. This changes it back to use default_llseek
in order to restore the original behaviour.
The problem with generic_file_llseek is that it only allows seeks up to
inode->i_sb->s_maxbytes, which is zero on procfs and some other virtual
file systems. We should merge generic_file_llseek and default_llseek some
day and clean this up in a proper way, but for 2.6.35/36, reverting vmcore
is the safer solution.
Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Frederic Weisbecker <fweisbec@gmail.com> Reported-by: CAI Qian <caiqian@redhat.com> Tested-by: CAI Qian <caiqian@redhat.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Rientjes [Wed, 22 Sep 2010 20:04:52 +0000 (13:04 -0700)]
oom: always return a badness score of non-zero for eligible tasks
A task's badness score is roughly a proportion of its rss and swap
compared to the system's capacity. The scale ranges from 0 to 1000 with
the highest score chosen for kill. Thus, this scale operates on a
resolution of 0.1% of RAM + swap. Admin tasks are also given a 3% bonus,
so the badness score of an admin task using 3% of memory, for example,
would still be 0.
It's possible that an exceptionally large number of tasks will combine to
exhaust all resources but never have a single task that uses more than
0.1% of RAM and swap (or 3.0% for admin tasks).
This patch ensures that the badness score of any eligible task is never 0
so the machine doesn't unnecessarily panic because it cannot find a task
to kill.
Signed-off-by: David Rientjes <rientjes@google.com> Cc: Dave Hansen <dave@linux.vnet.ibm.com> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dan Rosenberg [Wed, 22 Sep 2010 18:32:56 +0000 (14:32 -0400)]
Prevent freeing uninitialized pointer in compat_do_readv_writev
In 32-bit compatibility mode, the error handling for
compat_do_readv_writev() may free an uninitialized pointer, potentially
leading to all sorts of ugly memory corruption. This is reliably
triggerable by unprivileged users by invoking the readv()/writev()
syscalls with an invalid iovec pointer. The below patch fixes this to
emulate the non-compat version.
Introduced by commit b83733639a49 ("compat: factor out
compat_rw_copy_check_uvector from compat_do_readv_writev")
Signed-off-by: Dan Rosenberg <dan.j.rosenberg@gmail.com> Cc: stable@kernel.org (2.6.35) Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6:
sparc: Prevent no-handler signal syscall restart recursion.
sparc: Don't mask signal when we can't setup signal frame.
sparc64: Fix race in signal instruction flushing.
sparc64: Support RAW perf events.
Al Viro [Mon, 20 Sep 2010 20:48:57 +0000 (21:48 +0100)]
powerpc: fix double syscall restarts
Make sigreturn zero regs->trap, make do_signal() do the same on all
paths. As it is, signal interrupting e.g. read() from fd 512 (==
ERESTARTSYS) with another signal getting unblocked when the first
handler finishes will lead to restart one insn earlier than it ought
to. Same for multiple signals with in-kernel handlers interrupting
that sucker at the same time. Same for multiple signals of any kind
interrupting that sucker on 64bit...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Acked-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block
* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
bdi: Fix warnings in __mark_inode_dirty for /dev/zero and friends
char: Mark /dev/zero and /dev/kmem as not capable of writeback
bdi: Initialize noop_backing_dev_info properly
cfq-iosched: fix a kernel OOPs when usb key is inserted
block: fix blk_rq_map_kern bio direction flag
cciss: freeing uninitialized data on error path
Jan Kara [Tue, 21 Sep 2010 09:51:01 +0000 (11:51 +0200)]
bdi: Fix warnings in __mark_inode_dirty for /dev/zero and friends
Inodes of devices such as /dev/zero can get dirty for example via
utime(2) syscall or due to atime update. Backing device of such inodes
(zero_bdi, etc.) is however unable to handle dirty inodes and thus
__mark_inode_dirty complains. In fact, inode should be rather dirtied
against backing device of the filesystem holding it. This is generally a
good rule except for filesystems such as 'bdev' or 'mtd_inodefs'. Inodes
in these pseudofilesystems are referenced from ordinary filesystem
inodes and carry mapping with real data of the device. Thus for these
inodes we have to use inode->i_mapping->backing_dev_info as we did so
far. We distinguish these filesystems by checking whether sb->s_bdi
points to a non-trivial backing device or not.
Example: Assume we have an ext3 filesystem on /dev/sda1 mounted on /.
There's a device inode A described by a path "/dev/sdb" on this
filesystem. This inode will be dirtied against backing device "8:0"
after this patch. bdev filesystem contains block device inode B coupled
with our inode A. When someone modifies a page of /dev/sdb, it's B that
gets dirtied and the dirtying happens against the backing device "8:16".
Thus both inodes get filed to a correct bdi list.
Cc: stable@kernel.org Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
Jan Kara [Tue, 21 Sep 2010 09:49:01 +0000 (11:49 +0200)]
char: Mark /dev/zero and /dev/kmem as not capable of writeback
These devices don't do any writeback but their device inodes still can get
dirty so mark bdi appropriately so that bdi code does the right thing and files
inodes to lists of bdi carrying the device inodes.
Cc: stable@kernel.org Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>