Fix for inability of br_dump_ifinfo to handle non-zero start index:
loop index never increases when entered with non-zero start.
Spotted by Kirill Korotaev.
Signed-off-by: Andrey Savochkin <saw@swsoft.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Allan Stephens [Tue, 4 Jul 2006 02:39:36 +0000 (19:39 -0700)]
[TIPC] Fixed sk_buff panic caused by tipc_link_bundle_buf (REVISED)
The recent change to direct inspection of bundle buffer tailroom did not
account for the possiblity of unrequested tailroom added by skb_alloc(),
thereby allowing a bundle to be created that exceeds the current link MTU.
An additional check now ensures that bundling works correctly no matter
if the bundle buffer is smaller, larger, or equal to the link MTU.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com> Signed-off-by: Per Liden <per.liden@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
[ROSE]: Try all routes when establishing a ROSE connections.
From Jean-Paul F6FBB
ROSE will only try to establish a route using the first route in its
routing table. Fix to iterate through all additional routes if a
connection attempt has failed.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: David S. Miller <davem@davemloft.net>
drivers/dma/ioatdma.c: In function 'ioat_init_module':
drivers/dma/ioatdma.c:830: warning: control reaches end of non-void function
Signed-off-by: Benoit Boissinot <benoit.boissinot@ens-lyon.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc:
powerpc: add defconfig for Freescale MPC8349E-mITX board
powerpc: Add base support for the Freescale MPC8349E-mITX eval board
Documentation: correct values in MPC8548E SEC example node
[POWERPC] Actually copy over i8259.c to arch/ppc/syslib this time
[POWERPC] Add new interrupt mapping core and change platforms to use it
[POWERPC] Copy i8259 code back to arch/ppc
[POWERPC] New device-tree interrupt parsing code
[POWERPC] Use the genirq framework
[PATCH] genirq: Allow fasteoi handler to retrigger disabled interrupts
[POWERPC] Update the SWIM3 (powermac) floppy driver
[POWERPC] Fix error handling in detecting legacy serial ports
[POWERPC] Fix booting on Momentum "Apache" board (a Maple derivative)
[POWERPC] Fix various offb and BootX-related issues
[POWERPC] Add a default config for 32-bit CHRP machines
[POWERPC] fix implicit declaration on cell.
[POWERPC] change get_property to return void *
[PATCH] sched: cleanup, convert sched.c-internal typedefs to struct
convert:
- runqueue_t to 'struct rq'
- prio_array_t to 'struct prio_array'
- migration_req_t to 'struct migration_req'
I was the one who added these but they are both against the kernel coding
style and also were used inconsistently at places. So just get rid of them at
once, now that we are flushing the scheduler patch-queue anyway.
Conversion was mostly scripted, the result was reviewed and all secondary
whitespace and style impact (if any) was fixed up by hand.
Paul Mackerras [Mon, 3 Jul 2006 07:25:40 +0000 (00:25 -0700)]
[PATCH] lockdep: irqtrace subsystem, move account_system_vtime() calls into kernel/softirq.c
At the moment, powerpc and s390 have their own versions of do_softirq which
include local_bh_disable() and __local_bh_enable() calls. They end up
calling __do_softirq (in kernel/softirq.c) which also does
local_bh_disable/enable.
Apparently the two levels of disable/enable trigger a warning from some
validation code that Ingo is working on, and he would like to see the outer
level removed. But to do that, we have to move the account_system_vtime
calls that are currently in the arch do_softirq() implementations for
powerpc and s390 into the generic __do_softirq() (this is a no-op for other
archs because account_system_vtime is defined to be an empty inline
function on all other archs). This patch does that.
Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
nv_do_nic_poll() is called from timer softirqs, which has interrupts enabled,
but np->lock might also be taken by some other interrupt context.
The driver does disable_irq() to get around this problem, so annotate the
disable_irq()/enable_irq() calls for lockdep.
Has no effect on non-lockdep kernels.
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Cc: Ayaz Abdulla <aabdulla@nvidia.com> Cc: Manfred Spraul <manfred@colorfullife.com> Cc: Jeff Garzik <jeff@garzik.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
On Fri, 2006-06-30 at 15:45 -0700, Miles Lane wrote:
> Okay, I rebuilt my kernel with your combo patch applied.
> Then, I inserted my US Robotics USR2210 PCMCIA wifi card,
> ran "pccardutil eject", popped out the card and then inserted
> a Compaq iPaq wifi card. This triggered the following.
>
> [ INFO: possible circular locking dependency detected ]
> -------------------------------------------------------
> syslogd/1886 is trying to acquire lock:
> (&dev->queue_lock){-+..}, at: [<c11a50b5>] dev_queue_xmit+0x120/0x24b
>
> but task is already holding lock:
> (&dev->_xmit_lock){-+..}, at: [<c11a5118>] dev_queue_xmit+0x183/0x24b
>
> which lock already depends on the new lock.
ok this appears to be hostap playing games... it has 2 network devices
for one piece of hardware and one calls the other via the networking
layer; there is thankfully a natural ordering between the two, so just
making the slave one a separate type ought to make this work.
Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: "John W. Linville" <linville@tuxdriver.com> Cc: Jeff Garzik <jeff@garzik.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Teach sk_lock semantics to the lock validator. In the softirq path the
slock has mutex_trylock()+mutex_unlock() semantics, in the process context
sock_lock() case it has mutex_lock()/mutex_unlock() semantics.
Thus we treat sock_owned_by_user() flagged areas as an exclusion area too,
not just those areas covered by a held sk_lock.slock.
Effect on non-lockdep kernels: minimal, sk_lock_sock_init() has been turned
into an inline function.
Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
[PATCH] lockdep: annotate vlan net device as being a special class
vlan network devices have devices nesting below it, and are a special
"super class" of normal network devices; split their locks off into a
separate class since they always nest.
[deweerdt@free.fr: fix possible null-pointer deref] Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Frederik Deweerdt <frederik.deweerdt@gmail.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
extern int blkdev_put_partition(struct block_device *);
static int
blkdev_get_whole(struct block_device *bdev, mode_t mode, unsigned flags);
which on non-lockdep are the same as open_by_devnum(), blkdev_put()
and blkdev_get().
- a subclass parameter to do_open(). [unused on non-lockdep]
- a subclass parameter to __blkdev_put(), which is a new internal
function for the main blkdev_put*() functions. [parameter unused
on non-lockdep kernels, except for two sanity check WARN_ON()s]
these functions carry no semantical difference - they only express
object dependencies towards the lockdep subsystem.
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Cc: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Teach special (recursive) locking code to the lock validator. Has no effect
on non-lockdep kernels.
Fix initialize-locks-via-memcpy assumptions.
Effects on non-lockdep kernels: the subclass nesting parameter is passed into
cache_free_alien() and __cache_free(), and turns one internal
kmem_cache_free() call into an open-coded __cache_free() call.
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Christoph Lameter <clameter@engr.sgi.com> Cc: Manfred Spraul <manfred@colorfullife.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The s_umount rwsem needs to be classified as per-superblock since it's
perfectly legit to keep multiple of those recursively in the VFS locking
rules.
Has no effect on non-lockdep kernels.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Teach special (per-filesystem) locking code to the lock validator.
Minimal effect on non-lockdep kernels: one extra parameter to alloc_super().
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
lockdep needs to have the waitqueue lock initialized for on-stack waitqueues
implicitly initialized by DECLARE_COMPLETION(). Annotate on-stack completions
accordingly.
Make use of local_irq_enable_in_hardirq() API to annotate places that enable
hardirqs in hardirq context.
Has no effect on non-lockdep kernels.
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
3c59x.c's vortex_timer() function knows that vp->lock can only be used by an
irq context that it disabled - and can hence take the vp->lock without
disabling hardirqs. Teach lockdep about this.
Has no effect on non-lockdep kernels.
Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
8390.c knows that ei_local->page_lock can only be used by an irq context that
it disabled - and can hence take the ->page_lock without disabling hardirqs.
Teach lockdep about this.
Has no effect on non-lockdep kernels.
Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Jeff Garzik <jeff@garzik.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The ops structure has complex locking rules, where not all ops are equal, some
are subordinate on others for some complex sound cards. This requires for
lockdep checking that each individual reg_mutex is considered in separation
for its locking rules.
Has no effect on non-lockdep kernels.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Takashi Iwai <tiwai@suse.de> Cc: Jaroslav Kysela <perex@suse.cz> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
In usbfs's fs_remove_file() function, the aim is to remove a file or
directory from usbfs. This is done by first taking the i_mutex of the
parent directory of this file/dir via
mutex_lock(&parent->d_inode->i_mutex);
and then to call either usbfs_rmdir() for a directory or usbfs_unlink()
for a file. Both these functions then take the i_mutex for the
to-be-removed object themselves:
mutex_lock(&inode->i_mutex);
This is a classical parent->child locking order relationship that the VFS uses
all over the place; the VFS locking rule is "you need to take the parent
first". This patch annotates the usbfs code to make this explicit and thus
informs the lockdep code that those two locks indeed have this relationship.
The rules for unlink that we already use in the VFS for unlink are to use
I_MUTEX_PARENT for the parent directory, and a normal mutex for the file
itself; this patch follows that convention.
Has no effect on non-lockdep kernels.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The quota code plays interesting games with the lock ordering; to quote Jan:
| i_mutex of inode containing quota file is acquired after all other
| quota locks. i_mutex of all other inodes is acquired before quota
| locks. Quota code makes sure (by resetting inode operations and
| setting special flag on inode) that noone tries to enter quota code
| while holding i_mutex on a quota file...
The good news is that all of this special case i_mutex grabbing happens in the
(per filesystem) low level quota write function. For this special case we
need a new I_MUTEX_* nesting level, since this just entirely outside any of
the regular VFS locking rules for i_mutex. I trust Jan on his blue eyes that
this is not ever going to deadlock; and based on that the patch below is what
it takes to inform lockdep of these very interesting new locking rules.
The new locking rule for the I_MUTEX_QUOTA nesting level is that this is the
deepest possible level of nesting for i_mutex, and that this only should be
used in quota write (and possibly read) function of filesystems. This makes
the lock ordering of the I_MUTEX_* levels:
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: Jan Kara <jack@ucw.cz> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
NTFS uses lots of type-opaque objects which acquire their true identity
runtime - so the lock validator needs to be helped in a couple of places to
figure out object types.
Many thanks to Anton Altaparmakov for giving lots of explanations about NTFS
locking rules.
Has no effect on non-lockdep kernels.
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Anton Altaparmakov <aia21@cantab.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add i_mutex ordering annotations to the sunrpc rpc_pipe code. This code has 3
levels of i_mutex hierarchy in some cases: parent dir, client dir and file
inside client dir; the i_mutex ordering is I_MUTEX_PARENT -> I_MUTEX_CHILD ->
I_MUTEX_NORMAL
This patch applies this ordering annotation to the various functions. This is
in line with the VFS expected ordering where it is always OK to lock a child
after locking a parent; the sunrpc code is very diligent in doing this
correctly.
Has no effect on non-lockdep kernels.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Cc: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Teach special (recursive) locking code to the lock validator. Has no effect
on non-lockdep kernels.
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
ieee1394 reuses the skb infrastructure of the networking code, and uses two
skb-head queues: ->pending_packet_queue and hpsbpkt_queue. The latter is used
in the usual fashion: processed from a kernel thread. The other one,
->pending_packet_queue is also processed from hardirq context (f.e. in
hpsb_bus_reset()), which is not what the networking code usually does (which
completes from softirq or process context). This locking assymetry can be
totally correct if done carefully, but it can also be dangerous if networking
helper functions are reused, which could assume traditional networking use.
It would probably be more robust to push this completion into a workqueue -
but technically the code can be 100% correct, and lockdep has to be taught
about it. The solution is to split the ->pending_packet_queue skb-head->lock
class from the networking lock-class by using a private lock-validator key.
Has no effect on non-lockdep kernels.
Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Stefan Richter <stefanr@s5r6.in-berlin.de> Cc: Jody McIntyre <scjody@modernduck.com> Cc: Ben Collins <bcollins@debian.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Teach special (recursive) locking code to the lock validator. Has no effect
on non-lockdep kernels.
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Teach special (recursive) locking code to the lock validator. Also splits
af_unix's sk_receive_queue.lock class from the other networking skb-queue
locks. Has no effect on non-lockdep kernels.
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Teach special (multi-initialized, per-address-family) locking code to the lock
validator. Has no effect on non-lockdep kernels.
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Teach special (recursive) locking code to the lock validator. Has no effect
on non-lockdep kernels.
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Teach per-CPU runqueue locks and recursive locking code to the lock validator.
Has no effect on non-lockdep kernels.
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Split the per-CPU timer base locks up into separate lock classes, because they
are used recursively.
Has no effect on non-lockdep kernels.
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Teach special (multi-initialized) locking code to the lock validator. Has no
effect on non-lockdep kernels.
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The PS/2 code has a natural device order and there is a one level recursion in
this device order in terms of the cmd_mutex; annotate this explicit recursion
as ok.
Has no effect on non-lockdep kernels.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Cc: Dmitry Torokhov <dtor_core@ameritech.net> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Teach special (recursive) locking code to the lock validator. Has no effect
on non-lockdep kernels.
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Create one lock class for all waitqueue locks in the kernel. Has no effect on
non-lockdep kernels.
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Teach special (recursive) locking code to the lock validator. Has no effect
on non-lockdep kernels.
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Teach special (recursive) locking code to the lock validator. Introduces
double_lock_hb() to unify double- hash-bucket-lock taking.
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Teach special (recursive) locking code to the lock validator. Has no effect
on non-lockdep kernels.
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Teach special (recursive) locking code to the lock validator. Has no effect
on non-lockdep kernels.
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Teach special (dual-initialized) locking code to the lock validator. Has no
effect on non-lockdep kernels.
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Teach special (rwsem-in-irq) locking code to the lock validator. Has no
effect on non-lockdep kernels.
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
[PATCH] lockdep: s390 turn validator off in machine-check handler
Machine checks on s390 are always enabled (except in the machine check handler
itself). Therefore use lockdep_off()/on() in the machine check handler to
avoid deadlocks in the lock validator.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Arjan van de Ven <arjan@infradead.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
On lockdep we have a quite big spinlock_t, so keep the size down.
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Make printk()-ing from within the lock validation code safer by using the
lockdep-recursion counter.
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Disable SMP alternatives fixups (the patching in of NOPs on 1-CPU systems) if
the lock validator is enabled: there is a binutils section handling bug that
causes corrupted instructions when UP instructions are patched in.
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
[PATCH] lockdep: print all lock classes on SysRQ-D
Print all lock-classes on SysRq-D.
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Use the lock validator framework to prove mutex locking correctness.
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Use the lock validator framework to prove spinlock and rwlock locking
correctness.
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Use the lock validator framework to prove rwsem locking correctness.
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Lock validator /proc/lockdep and /proc/lockdep_stats support.
(FIXME: should go into debugfs)
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
[PATCH] lockdep: allow read_lock() recursion of same class
From: Ingo Molnar <mingo@elte.hu>
lockdep so far only allowed read-recursion for the same lock instance.
This is enough in the overwhelming majority of cases, but a hostap case
triggered and reported by Miles Lane relies on same-class
different-instance recursion. So we relax the restriction on read-lock
recursion.
(This change does not allow rwsem read-recursion, which is still
forbidden.)
Do 'make oldconfig' and accept all the defaults for new config options -
reboot into the kernel and if everything goes well it should boot up fine and
you should have /proc/lockdep and /proc/lockdep_stats files.
Typically if the lock validator finds some problem it will print out
voluminous debug output that begins with "BUG: ..." and which syslog output
can be used by kernel developers to figure out the precise locking scenario.
What does the lock validator do? It "observes" and maps all locking rules as
they occur dynamically (as triggered by the kernel's natural use of spinlocks,
rwlocks, mutexes and rwsems). Whenever the lock validator subsystem detects a
new locking scenario, it validates this new rule against the existing set of
rules. If this new rule is consistent with the existing set of rules then the
new rule is added transparently and the kernel continues as normal. If the
new rule could create a deadlock scenario then this condition is printed out.
When determining validity of locking, all possible "deadlock scenarios" are
considered: assuming arbitrary number of CPUs, arbitrary irq context and task
context constellations, running arbitrary combinations of all the existing
locking scenarios. In a typical system this means millions of separate
scenarios. This is why we call it a "locking correctness" validator - for all
rules that are observed the lock validator proves it with mathematical
certainty that a deadlock could not occur (assuming that the lock validator
implementation itself is correct and its internal data structures are not
corrupted by some other kernel subsystem). [see more details and conditionals
of this statement in include/linux/lockdep.h and
Documentation/lockdep-design.txt]
Furthermore, this "all possible scenarios" property of the validator also
enables the finding of complex, highly unlikely multi-CPU multi-context races
via single single-context rules, increasing the likelyhood of finding bugs
drastically. In practical terms: the lock validator already found a bug in
the upstream kernel that could only occur on systems with 3 or more CPUs, and
which needed 3 very unlikely code sequences to occur at once on the 3 CPUs.
That bug was found and reported on a single-CPU system (!). So in essence a
race will be found "piecemail-wise", triggering all the necessary components
for the race, without having to reproduce the race scenario itself! In its
short existence the lock validator found and reported many bugs before they
actually caused a real deadlock.
To further increase the efficiency of the validator, the mapping is not per
"lock instance", but per "lock-class". For example, all struct inode objects
in the kernel have inode->inotify_mutex. If there are 10,000 inodes cached,
then there are 10,000 lock objects. But ->inotify_mutex is a single "lock
type", and all locking activities that occur against ->inotify_mutex are
"unified" into this single lock-class. The advantage of the lock-class
approach is that all historical ->inotify_mutex uses are mapped into a single
(and as narrow as possible) set of locking rules - regardless of how many
different tasks or inode structures it took to build this set of rules. The
set of rules persist during the lifetime of the kernel.
To see the rough magnitude of checking that the lock validator does, here's a
portion of /proc/lockdep_stats, fresh after bootup:
[bunk@stusta.de: cleanups] Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Introduce DEBUG_LOCKING_API_SELFTESTS, which uses the generic lock debugging
code's silent-failure feature to run a matrix of testcases. There are 210
testcases currently:
+-----------------------
| Locking API testsuite:
+------------------------------+------+------+------+------+------+------+
| spin |wlock |rlock |mutex | wsem | rsem |
-------------------------------+------+------+------+------+------+------+
A-A deadlock: ok | ok | ok | ok | ok | ok |
A-B-B-A deadlock: ok | ok | ok | ok | ok | ok |
A-B-B-C-C-A deadlock: ok | ok | ok | ok | ok | ok |
A-B-C-A-B-C deadlock: ok | ok | ok | ok | ok | ok |
A-B-B-C-C-D-D-A deadlock: ok | ok | ok | ok | ok | ok |
A-B-C-D-B-D-D-A deadlock: ok | ok | ok | ok | ok | ok |
A-B-C-D-B-C-D-A deadlock: ok | ok | ok | ok | ok | ok |
double unlock: ok | ok | ok | ok | ok | ok |
bad unlock order: ok | ok | ok | ok | ok | ok |
--------------------------------------+------+------+------+------+------+
recursive read-lock: | ok | | ok |
--------------------------------------+------+------+------+------+------+
non-nested unlock: ok | ok | ok | ok |
--------------------------------------+------+------+------+
hard-irqs-on + irq-safe-A/12: ok | ok | ok |
soft-irqs-on + irq-safe-A/12: ok | ok | ok |
hard-irqs-on + irq-safe-A/21: ok | ok | ok |
soft-irqs-on + irq-safe-A/21: ok | ok | ok |
sirq-safe-A => hirqs-on/12: ok | ok | ok |
sirq-safe-A => hirqs-on/21: ok | ok | ok |
hard-safe-A + irqs-on/12: ok | ok | ok |
soft-safe-A + irqs-on/12: ok | ok | ok |
hard-safe-A + irqs-on/21: ok | ok | ok |
soft-safe-A + irqs-on/21: ok | ok | ok |
hard-safe-A + unsafe-B #1/123: ok | ok | ok |
soft-safe-A + unsafe-B #1/123: ok | ok | ok |
hard-safe-A + unsafe-B #1/132: ok | ok | ok |
soft-safe-A + unsafe-B #1/132: ok | ok | ok |
hard-safe-A + unsafe-B #1/213: ok | ok | ok |
soft-safe-A + unsafe-B #1/213: ok | ok | ok |
hard-safe-A + unsafe-B #1/231: ok | ok | ok |
soft-safe-A + unsafe-B #1/231: ok | ok | ok |
hard-safe-A + unsafe-B #1/312: ok | ok | ok |
soft-safe-A + unsafe-B #1/312: ok | ok | ok |
hard-safe-A + unsafe-B #1/321: ok | ok | ok |
soft-safe-A + unsafe-B #1/321: ok | ok | ok |
hard-safe-A + unsafe-B #2/123: ok | ok | ok |
soft-safe-A + unsafe-B #2/123: ok | ok | ok |
hard-safe-A + unsafe-B #2/132: ok | ok | ok |
soft-safe-A + unsafe-B #2/132: ok | ok | ok |
hard-safe-A + unsafe-B #2/213: ok | ok | ok |
soft-safe-A + unsafe-B #2/213: ok | ok | ok |
hard-safe-A + unsafe-B #2/231: ok | ok | ok |
soft-safe-A + unsafe-B #2/231: ok | ok | ok |
hard-safe-A + unsafe-B #2/312: ok | ok | ok |
soft-safe-A + unsafe-B #2/312: ok | ok | ok |
hard-safe-A + unsafe-B #2/321: ok | ok | ok |
soft-safe-A + unsafe-B #2/321: ok | ok | ok |
hard-irq lock-inversion/123: ok | ok | ok |
soft-irq lock-inversion/123: ok | ok | ok |
hard-irq lock-inversion/132: ok | ok | ok |
soft-irq lock-inversion/132: ok | ok | ok |
hard-irq lock-inversion/213: ok | ok | ok |
soft-irq lock-inversion/213: ok | ok | ok |
hard-irq lock-inversion/231: ok | ok | ok |
soft-irq lock-inversion/231: ok | ok | ok |
hard-irq lock-inversion/312: ok | ok | ok |
soft-irq lock-inversion/312: ok | ok | ok |
hard-irq lock-inversion/321: ok | ok | ok |
soft-irq lock-inversion/321: ok | ok | ok |
hard-irq read-recursion/123: ok |
soft-irq read-recursion/123: ok |
hard-irq read-recursion/132: ok |
soft-irq read-recursion/132: ok |
hard-irq read-recursion/213: ok |
soft-irq read-recursion/213: ok |
hard-irq read-recursion/231: ok |
soft-irq read-recursion/231: ok |
hard-irq read-recursion/312: ok |
soft-irq read-recursion/312: ok |
hard-irq read-recursion/321: ok |
soft-irq read-recursion/321: ok |
--------------------------------+-----+----------------
Good, all 210 testcases passed! |
--------------------------------+
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Accurate hard-IRQ-flags and softirq-flags state tracing.
This allows us to attach extra functionality to IRQ flags on/off
events (such as trace-on/off).
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
[PATCH] lockdep: stacktrace subsystem, i386 support
Framework to generate and save stacktraces quickly, without printing anything
to the console. i386 support.
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Framework to generate and save stacktraces quickly, without printing anything
to the console.
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
[PATCH] lockdep: i386 remove multi entry backtraces
Remove CONFIG_STACK_BACKTRACE_COLS.
This feature didnt work out: instead of making kernel debugging more
efficient, it produces much harder to read stacktraces! Check out this trace
for example:
- introduce and use __SPIN_LOCK_UNLOCKED for array initializations,
to pass in the name string of locks, used by debugging
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Work around weird section nesting build bug causing smp-alternatives failures
under certain circumstances.
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
projects / linux-2.6 / log