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>
Sage Weil [Tue, 21 Sep 2010 21:35:37 +0000 (14:35 -0700)]
fs: {lock,unlock}_flocks() stubs to prepare for BKL removal
The lock structs are currently protected by the BKL, but are accessed by
code in fs/locks.c and misc file system and DLM code. These stubs will
allow all users to switch to the new interface before the implementation
is changed to a spinlock.
Mathias Nyman [Thu, 26 Aug 2010 07:36:44 +0000 (07:36 +0000)]
i2c-omap: Make sure i2c bus is free before setting it to idle
If the i2c bus receives an interrupt with both BB (bus busy) and
ARDY (register access ready) statuses set during the tranfer of the last message
the bus was put to idle while still busy.
This caused bus to timeout.
Signed-off-by: Mathias Nyman <mathias.nyman@nokia.com> Acked-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Merge branch 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
sched: Fix nohz balance kick
sched: Fix user time incorrectly accounted as system time on 32-bit
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
ceph: select CRYPTO
ceph: check mapping to determine if FILE_CACHE cap is used
ceph: only send one flushsnap per cap_snap per mds session
ceph: fix cap_snap and realm split
ceph: stop sending FLUSHSNAPs when we hit a dirty capsnap
ceph: correctly set 'follows' in flushsnap messages
ceph: fix dn offset during readdir_prepopulate
ceph: fix file offset wrapping at 4GB on 32-bit archs
ceph: fix reconnect encoding for old servers
ceph: fix pagelist kunmap tail
ceph: fix null pointer deref on anon root dentry release
Merge branch 'drm-intel-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/ickle/drm-intel
* 'drm-intel-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/ickle/drm-intel:
drm/i915: Hold a reference to the object whilst unbinding the eviction list
drm/i915,agp/intel: Add second set of PCI-IDs for B43
drm/i915: Fix Sandybridge fence registers
drm/i915/crt: Downgrade warnings for hotplug failures
drm/i915: Ensure that the crtcinfo is populated during mode_fixup()
* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus:
lguest: update comments to reflect LHCALL_LOAD_GDT_ENTRY.
virtio: console: Prevent userspace from submitting NULL buffers
virtio: console: Fix poll blocking even though there is data to read
There's a situation where the nohz balancer will try to wake itself:
cpu-x is idle which is also ilb_cpu
got a scheduler tick during idle
and the nohz_kick_needed() in trigger_load_balance() checks for
rq_x->nr_running which might not be zero (because of someone waking a
task on this rq etc) and this leads to the situation of the cpu-x
sending a kick to itself.
And this can cause a lockup.
Avoid this by not marking ourself eligible for kicking.
cfq-iosched: fix a kernel OOPs when usb key is inserted
Mike reported a kernel crash when a usb key hotplug is performed while all
kernel thrads are not in a root cgroup and are running in one of the child
cgroups of blkio controller.
BUG: unable to handle kernel NULL pointer dereference at 0000002c
IP: [<c11c7b08>] cfq_get_queue+0x232/0x412
*pde = 00000000
Oops: 0000 [#1] PREEMPT
last sysfs file: /sys/devices/pci0000:00/0000:00:1d.7/usb2/2-1/2-1:1.0/host3/scsi_host/host3/uevent
The problem here is that we don't have bdi->dev information available when
thread does some IO. Hence when dev_name() tries to access bdi->dev, it
crashes.
This problem does not happen if kernel threads are in root group as root
group is statically allocated at device initialization time and we don't
hit this piece of code.
Fix it by delaying the filling of major and minor number information of
device in blk_group. Initially a blk_group is created with 0 as device
information and this information is filled later once some more IO comes
in from same group.
Dan Carpenter [Mon, 13 Sep 2010 12:09:33 +0000 (14:09 +0200)]
cciss: freeing uninitialized data on error path
The "h->scatter_list" is allocated inside a for loop. If any of those
allocations fail, then the rest of the list is uninitialized data. When
we free it we should start from the top and free backwards so that we
don't call kfree() on uninitialized pointers.
Also if the allocation for "h->scatter_list" fails then we would get an
Oops here. I should have noticed this when I send: 4ee69851c "cciss:
handle allocation failure." but I didn't. Sorry about that.
Signed-off-by: Dan Carpenter <error27@gmail.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
David S. Miller [Tue, 21 Sep 2010 06:24:52 +0000 (23:24 -0700)]
sparc64: Fix race in signal instruction flushing.
If another cpu does a very wide munmap() on the signal frame area,
it can tear down the page table hierarchy from underneath us.
Borrow an idea from the 64-bit fault path's get_user_insn(), and
disable cross call interrupts during the page table traversal
to lock them in place while we operate.
Reported-by: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
Amit Shah [Tue, 14 Sep 2010 07:56:16 +0000 (13:26 +0530)]
virtio: console: Prevent userspace from submitting NULL buffers
A userspace could submit a buffer with 0 length to be written to the
host. Prevent such a situation.
This was not needed previously, but recent changes in the way write()
works exposed this condition to trigger a virtqueue event to the host,
causing a NULL buffer to be sent across.
Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> CC: stable@kernel.org
Hans de Goede [Thu, 16 Sep 2010 09:13:08 +0000 (14:43 +0530)]
virtio: console: Fix poll blocking even though there is data to read
I found this while working on a Linux agent for spice, the symptom I was
seeing was select blocking on the spice vdagent virtio serial port even
though there were messages queued up there.
virtio_console's port_fops_poll checks port->inbuf != NULL to determine
if read won't block. However if an application reads enough bytes from
inbuf through port_fops_read, to empty the current port->inbuf,
port->inbuf will be NULL even though there may be buffers left in the
virtqueue.
This causes poll() to block even though there is data to be read,
this patch fixes this by using will_read_block(port) instead of the
port->inbuf != NULL check.
Signed-off-By: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: stable@kernel.org
Dan Carpenter [Mon, 6 Sep 2010 12:32:30 +0000 (14:32 +0200)]
Staging: vt6655: fix buffer overflow
"param->u.wpa_associate.wpa_ie_len" comes from the user. We should
check it so that the copy_from_user() doesn't overflow the buffer.
Also further down in the function, we assume that if
"param->u.wpa_associate.wpa_ie_len" is set then "abyWPAIE[0]" is
initialized. To make that work, I changed the test here to say that if
"wpa_ie_len" is set then "wpa_ie" has to be a valid pointer or we return
-EINVAL.
Oddly, we only use the first element of the abyWPAIE[] array. So I
suspect there may be some other issues in this function.
The netfilter hook seems to be misused and may leak skbs in situations
when NF_HOOK returns NF_STOLEN. It may not filter everything as
expected. Also the ethernet bridge tables are not yet capable to
understand batman-adv packet correctly.
It was only added for testing purposes and can be removed again.
Mika Westerberg [Sat, 4 Sep 2010 07:23:23 +0000 (10:23 +0300)]
serial: amba-pl010: fix set_ldisc
Commit d87d9b7d1 ("tty: serial - fix tty referencing in set_ldisc") changed
set_ldisc to take ldisc number as parameter. This patch fixes AMBA PL010 driver
according the new prototype.
Signed-off-by: Mika Westerberg <mika.westerberg@iki.fi> Cc: Alan Cox <alan@linux.intel.com> Cc: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The TIOCGICOUNT device ioctl in both mos7720.c and mos7840.c allows
unprivileged users to read uninitialized stack memory, because the
"reserved" member of the serial_icounter_struct struct declared on the
stack is not altered or zeroed before being copied back to the user.
This patch takes care of it.
Ming Lei [Mon, 6 Sep 2010 15:27:09 +0000 (23:27 +0800)]
USB: otg: twl4030: fix phy initialization(v1)
Commit 461c317705eca5cac09a360f488715927fd0a927(into 2.6.36-v3)
is put forward to power down phy if no usb cable is connected,
but does introduce the two issues below:
1), phy is not into work state if usb cable is connected
with PC during poweron, so musb device mode is not usable
in such case, follows the reasons:
-twl4030_phy_resume is not called, so
regulators are not enabled
i2c access are not enabled
usb mode not configurated
2), The kernel warings[1] of regulators 'unbalanced disables'
is caused if poweron without usb cable connected
with PC or b-device.
This patch fixes the two issues above:
-power down phy only if no usb cable is connected with PC
and b-device
-do phy initialization(via __twl4030_phy_resume) if usb cable
is connected with PC(vbus event) or another b-device(ID event) in
twl4030_usb_probe.
This patch also doesn't put VUSB3V1 LDO into active mode in
twl4030_usb_ldo_init until VBUS/ID change detected, so we can
save more power consumption than before.
This patch is verified OK on Beagle board either connected with
usb cable or not when poweron.
Signed-off-by: Ming Lei <tom.leiming@gmail.com> Cc: David Brownell <dbrownell@users.sourceforge.net> Cc: Felipe Balbi <me@felipebalbi.com> Cc: Anand Gadiyar <gadiyar@ti.com> Cc: Mike Frysinger <vapier@gentoo.org> Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
usb: musb_debugfs: don't use the struct file private_data field with seq_files
seq_files use the private_data field of a file struct for storing a seq_file structure,
data should be stored in seq_file's own private field (e.g. file->private_data->private)
Otherwise seq_release() will free the private data when the file is closed.
Chris Wilson [Mon, 20 Sep 2010 09:31:40 +0000 (10:31 +0100)]
drm/i915: Hold a reference to the object whilst unbinding the eviction list
During heavy aperture thrashing we may be forced to wait upon several active
objects during eviction. The active list may be the last reference to
these objects and so the action of waiting upon one of them may cause
another to be freed (and itself unbound). To prevent the object
disappearing underneath us, we need to acquire and hold a reference
whilst unbinding.
Reported-by: Shawn Starr <shawn.starr@rogers.com>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=18902 Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Al Viro [Mon, 20 Sep 2010 14:13:25 +0000 (15:13 +0100)]
frv: double syscall restarts, syscall restart in sigreturn()
We need to make sure that only the first do_signal() to be handled on
the way out syscall will bother with syscall restarts; additionally, the
check on the "signal has user handler" path had been wrong - compare
with restart prevention in sigreturn()...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Al Viro [Mon, 20 Sep 2010 14:13:14 +0000 (15:13 +0100)]
frv: avoid infinite loop of SIGSEGV delivery
Use force_sigsegv() rather than force_sig(SIGSEGV, ...) as the former
resets the SEGV handler pointer which will kill the process, rather than
leaving it open to an infinite loop if the SEGV handler itself caused a
SEGV signal.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Al Viro [Mon, 20 Sep 2010 14:13:09 +0000 (15:13 +0100)]
frv: fix address verification holes in setup_frame/setup_rt_frame
a) sa_handler might be maliciously set to point to kernel memory;
blindly dereferencing it in FDPIC case is a Bad Idea(tm).
b) I'm not sure you need that set_fs(USER_DS) there at all, but if you
do, you'd better do it *before* checking the frame you've decided to
use with access_ok(), lest sigaltstack() becomes a convenient
roothole.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 4969c1192d15 ("mm: fix swapin race condition") is now agreed to
be incomplete. There's a race, not very much less likely than the
original race envisaged, in which it is further necessary to check that
the swapcache page's swap has not changed.
Here's the reasoning: cast in terms of reuse_swap_page(), but probably
could be reformulated to rely on try_to_free_swap() instead, or on
swapoff+swapon.
A, faults into do_swap_page(): does page1 = lookup_swap_cache(swap1) and
comes through the lock_page(page1).
B, a racing thread of the same process, faults on the same address: does
page1 = lookup_swap_cache(swap1) and now waits in lock_page(page1), but
for whatever reason is unlucky not to get the lock any time soon.
A carries on through do_swap_page(), a write fault, but cannot reuse the
swap page1 (another reference to swap1). Unlocks the page1 (but B
doesn't get it yet), does COW in do_wp_page(), page2 now in that pte.
C, perhaps the parent of A+B, comes in and write faults the same swap
page1 into its mm, reuse_swap_page() succeeds this time, swap1 is freed.
kswapd comes in after some time (B still unlucky) and swaps out some
pages from A+B and C: it allocates the original swap1 to page2 in A+B,
and some other swap2 to the original page1 now in C. But does not
immediately free page1 (actually it couldn't: B holds a reference),
leaving it in swap cache for now.
B at last gets the lock on page1, hooray! Is PageSwapCache(page1)? Yes.
Is pte_same(*page_table, orig_pte)? Yes, because page2 has now been
given the swap1 which page1 used to have. So B proceeds to insert page1
into A+B's page_table, though its content now belongs to C, quite
different from what A wrote there.
B ought to have checked that page1's swap was still swap1.
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mattst88/alpha-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mattst88/alpha-2.6:
alpha: deal with multiple simultaneously pending signals
alpha: fix a 14 years old bug in sigreturn tracing
alpha: unb0rk sigsuspend() and rt_sigsuspend()
alpha: belated ERESTART_RESTARTBLOCK race fix
alpha: Shift perf event pending work earlier in timer interrupt
alpha: wire up fanotify and prlimit64 syscalls
alpha: kill big kernel lock
alpha: fix build breakage in asm/cacheflush.h
alpha: remove unnecessary cast from void* in assignment.
alpha: Use static const char * const where possible
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (21 commits)
dca: disable dca on IOAT ver.3.0 multiple-IOH platforms
netpoll: Disable IRQ around RCU dereference in netpoll_rx
sctp: Do not reset the packet during sctp_packet_config().
net/llc: storing negative error codes in unsigned short
MAINTAINERS: move atlx discussions to netdev
drivers/net/cxgb3/cxgb3_main.c: prevent reading uninitialized stack memory
drivers/net/eql.c: prevent reading uninitialized stack memory
drivers/net/usb/hso.c: prevent reading uninitialized memory
xfrm: dont assume rcu_read_lock in xfrm_output_one()
r8169: Handle rxfifo errors on 8168 chips
3c59x: Remove atomic context inside vortex_{set|get}_wol
tcp: Prevent overzealous packetization by SWS logic.
net: RPS needs to depend upon USE_GENERIC_SMP_HELPERS
phylib: fix PAL state machine restart on resume
net: use rcu_barrier() in rollback_registered_many
bonding: correctly process non-linear skbs
ipv4: enable getsockopt() for IP_NODEFRAG
ipv4: force_igmp_version ignored when a IGMPv3 query received
ppp: potential NULL dereference in ppp_mp_explode()
net/llc: make opt unsigned in llc_ui_setsockopt()
...
Jan Harkes [Sat, 18 Sep 2010 03:26:01 +0000 (23:26 -0400)]
Coda: mount hangs because of missed REQ_WRITE rename
Coda's REQ_* defines were renamed to avoid clashes with the block layer
(commit 4aeefdc69f7b: "coda: fixup clash with block layer REQ_*
defines").
However one was missed and response messages are no longer matched with
requests and waiting threads are no longer woken up. This patch fixes
this.
Signed-off-by: Jan Harkes <jaharkes@cs.cmu.edu>
[ Also fixed up whitespace while at it -Linus ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Al Viro [Sat, 18 Sep 2010 12:42:27 +0000 (08:42 -0400)]
alpha: deal with multiple simultaneously pending signals
Unlike the other targets, alpha sets _one_ sigframe and
buggers off until the next syscall/interrupt, even if
more signals are pending. It leads to quite a few unpleasant
inconsistencies, starting with SIGSEGV potentially arriving
not where it should and including e.g. mess with sigsuspend();
consider two pending signals blocked until sigsuspend()
unblocks them. We pick the first one; then, if we are hit
by interrupt while in the handler, we process the second one
as well. If we are not, and if no syscalls had been made,
we get out of the first handler and leave the second signal
pending; normally sigreturn() would've picked it anyway, but
here it starts with restoring the original mask and voila -
the second signal is blocked again. On everything else we
get both delivered consistently.
It's actually easy to fix; the only thing to watch out for
is prevention of double syscall restart. Fortunately, the
idea I've nicked from arm fix by rmk works just fine...
Testcase demonstrating the behaviour in question; on alpha
we get one or both flags set (usually one), on everything
else both are always set.
#include <signal.h>
#include <stdio.h>
int had1, had2;
void f1(int sig) { had1 = 1; }
void f2(int sig) { had2 = 1; }
main()
{
sigset_t set1, set2;
sigemptyset(&set1);
sigemptyset(&set2);
sigaddset(&set2, 1);
sigaddset(&set2, 2);
signal(1, f1);
signal(2, f2);
sigprocmask(SIG_SETMASK, &set2, NULL);
raise(1);
raise(2);
sigsuspend(&set1);
printf("had1:%d had2:%d\n", had1, had2);
}
Tested-by: Michael Cree <mcree@orcon.net.nz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Matt Turner <mattst88@gmail.com>
Al Viro [Sat, 18 Sep 2010 12:41:16 +0000 (08:41 -0400)]
alpha: fix a 14 years old bug in sigreturn tracing
The way sigreturn() is implemented on alpha breaks PTRACE_SYSCALL,
all way back to 1.3.95 when alpha has grown PTRACE_SYSCALL support.
What happens is direct return to ret_from_syscall, in order to bypass
mangling of a3 (error indicator) and prevent other mutilations of
registers (e.g. by syscall restart). That's fine, but... the entire
TIF_SYSCALL_TRACE codepath is kept separate on alpha and post-syscall
stopping/notifying the tracer is after the syscall. And the normal
path we are forcibly switching to doesn't have it.
So we end up with *one* stop in traced sigreturn() vs. two in other
syscalls. And yes, strace is visibly broken by that; try to strace
the following
#include <signal.h>
#include <stdio.h>
void f(int sig) {}
main()
{
signal(SIGHUP, f);
raise(SIGHUP);
write(1, "eeeek\n", 6);
}
and watch the show. The
close(1) = 405
in the end of strace output is coming from return value of write() (6 ==
__NR_close on alpha) and syscall number of exit_group() (__NR_exit_group ==
405 there).
The fix is fairly simple - the only thing we end up missing is the call
of syscall_trace() and we can tell whether we'd been called from the
SYSCALL_TRACE path by checking ra value. Since we are setting the
switch_stack up (that's what sys_sigreturn() does), we have the right
environment for calling syscall_trace() - just before we call
undo_switch_stack() and return. Since undo_switch_stack() will overwrite
s0 anyway, we can use it to store the result of "has it been called from
SYSCALL_TRACE path?" check. The same thing applies in rt_sigreturn().
Tested-by: Michael Cree <mcree@orcon.net.nz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Matt Turner <mattst88@gmail.com>
Al Viro [Sat, 18 Sep 2010 12:40:07 +0000 (08:40 -0400)]
alpha: unb0rk sigsuspend() and rt_sigsuspend()
Old code used to set regs->r0 and regs->r19 to force the right
return value. Leaving that after switch to ERESTARTNOHAND
was a Bad Idea(tm), since now that screws the restart - if we
hit the case when get_signal_to_deliver() returns 0, we will
step back to syscall insn, with v0 set to EINTR and a3 to 1.
The latter won't matter, since EINTR is 4, aka __NR_write.
results on alpha in immediate message to stdout...
Fix is obvious; moreover, since we don't need regs anymore, we can
switch to normal prototypes for these guys and lose the wrappers.
Even better, rt_sigsuspend() is identical to generic version in
kernel/signal.c now.
Tested-by: Michael Cree <mcree@orcon.net.nz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Matt Turner <mattst88@gmail.com>
Michael Cree [Sun, 19 Sep 2010 06:05:40 +0000 (02:05 -0400)]
alpha: Shift perf event pending work earlier in timer interrupt
Pending work from the performance event subsystem is executed in
the timer interrupt. This patch shifts the call to
perf_event_do_pending() before the call to update_process_times()
as the latter may call back into the perf event subsystem and it
is prudent to have the pending work executed first.
Signed-off-by: Michael Cree <mcree@orcon.net.nz> Signed-off-by: Matt Turner <mattst88@gmail.com>
All uses of the BKL on alpha are totally bogus, nothing
is really protected by this. Remove the remaining users
so we don't have to mark alpha as 'depends on BKL'.
Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: linux-alpha@vger.kernel.org Signed-off-by: Matt Turner <mattst88@gmail.com>
Alpha SMP flush_icache_user_range() is implemented as an inline
function inside include/asm/cacheflush.h. It dereferences @current
but doesn't include linux/sched.h and thus causes build failure if
linux/sched.h wasn't included previously. Fix it by including the
needed header file explicitly.
Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Matt Turner <mattst88@gmail.com>
dca: disable dca on IOAT ver.3.0 multiple-IOH platforms
Direct Cache Access is not supported on IOAT ver.3.0 multiple-IOH platforms.
This patch blocks registering of dca providers when multiple IOH detected with IOAT ver.3.0.
Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Herbert Xu [Fri, 17 Sep 2010 23:55:03 +0000 (16:55 -0700)]
netpoll: Disable IRQ around RCU dereference in netpoll_rx
We cannot use rcu_dereference_bh safely in netpoll_rx as we may
be called with IRQs disabled. We could however simply disable
IRQs as that too causes BH to be disabled and is safe in either
case.
Thanks to John Linville for discovering this bug and providing
a patch.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
sctp: Do not reset the packet during sctp_packet_config().
sctp_packet_config() is called when getting the packet ready
for appending of chunks. The function should not touch the
current state, since it's possible to ping-pong between two
transports when sending, and that can result packet corruption
followed by skb overlfow crash.
Reported-by: Thomas Dreibholz <dreibh@iem.uni-due.de> Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Merge branch 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging
* 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging:
hwmon: (lm95241) Replace rate sysfs attribute with update_interval
hwmon: (adm1031) Replace update_rate sysfs attribute with update_interval
hwmon: (w83627ehf) Use proper exit sequence
hwmon: (emc1403) Remove unnecessary hwmon_device_unregister
hwmon: (f75375s) Do not overwrite values read from registers
hwmon: (f75375s) Shift control mode to the correct bit position
hwmon: New subsystem maintainers
hwmon: (lis3lv02d) Prevent NULL pointer dereference
Merge branch 'for-linus' of git://neil.brown.name/md
* 'for-linus' of git://neil.brown.name/md:
md: fix v1.x metadata update when a disk is missing.
md: call md_update_sb even for 'external' metadata arrays.
Al Viro [Fri, 17 Sep 2010 13:34:39 +0000 (14:34 +0100)]
arm: fix really nasty sigreturn bug
If a signal hits us outside of a syscall and another gets delivered
when we are in sigreturn (e.g. because it had been in sa_mask for
the first one and got sent to us while we'd been in the first handler),
we have a chance of returning from the second handler to location one
insn prior to where we ought to return. If r0 happens to contain -513
(-ERESTARTNOINTR), sigreturn will get confused into doing restart
syscall song and dance.
Incredible joy to debug, since it manifests as random, infrequent and
very hard to reproduce double execution of instructions in userland
code...
The fix is simple - mark it "don't bother with restarts" in wrapper,
i.e. set r8 to 0 in sys_sigreturn and sys_rt_sigreturn wrappers,
suppressing the syscall restart handling on return from these guys.
They can't legitimately return a restart-worthy error anyway.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> Cc: stable@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Sage Weil [Fri, 17 Sep 2010 16:54:08 +0000 (09:54 -0700)]
ceph: check mapping to determine if FILE_CACHE cap is used
See if the i_data mapping has any pages to determine if the FILE_CACHE
capability is currently in use, instead of assuming it is any time the
rdcache_gen value is set (i.e., issued -> used).
This allows the MDS RECALL_STATE process work for inodes that have cached
pages.
hwmon: (adm1031) Replace update_rate sysfs attribute with update_interval
The attribute reflects an interval, not a rate.
Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com> Acked-by: Ira W. Snyder <iws@ovro.caltech.edu> Signed-off-by: Jean Delvare <khali@linux-fr.org>
hwmon: (f75375s) Do not overwrite values read from registers
All bits in the values read from registers to be used for the next
write were getting overwritten, avoid doing so to not mess with the
current configuration.
hwmon: (f75375s) Shift control mode to the correct bit position
The spec notes that fan0 and fan1 control mode bits are located in bits
7-6 and 5-4 respectively, but the FAN_CTRL_MODE macro was making the
bits shift by 5 instead of by 4.
Jean Delvare [Fri, 17 Sep 2010 15:24:11 +0000 (17:24 +0200)]
hwmon: New subsystem maintainers
Guenter Roeck volunteered to adopt the hwmon subsystem as long as he
wasn't the only maintainer. As this was also my own condition, we can
add the two of us as co-maintainers of the hwmon subsystem.
Signed-off-by: Jean Delvare <khali@linux-fr.org> Acked-by: Guenter Roeck <guenter.roeck@ericsson.com>
Sage Weil [Fri, 17 Sep 2010 15:03:08 +0000 (08:03 -0700)]
ceph: only send one flushsnap per cap_snap per mds session
Sending multiple flushsnap messages is problematic because we ignore
the response if the tid doesn't match, and the server may only respond to
each one once. It's also a waste.
So, skip cap_snaps that are already on the flushing list, unless the caller
tells us to resend (because we are reconnecting).