Impact: avoid recursive kfree calls, less slab activity on heavy load

debugobjects checks on kfree whether tracked objects are freed. When a
tracked object is freed debugobjects frees the internal reference
object as well. The debug object slab cache is marked to not recurse
into debugobjects when a slab objects is freed, but the recursive call
can be problematic versus locking in the memory allocator.

Defer the freeing of debug slab objects via schedule_work. The reasons
not to use RCU are:

1) rcu makes the data structure larger
2) there is no real need for rcu as nothing references the obj after
   we freed it
3) under heavy load it is easier to reuse the to be freed objects instead
   of allocating new objects from the slab. This lowered the slab activity
   significantly in a heavy load networking test where lots of timers are
   created/destroyed. The workqueue based delayed free allows us just to
   put the to be freed objects back into the object pool and reuse them
   right away.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
LKML-Reference: <200903162049.58058.nickpiggin@yahoo.com.au>

Impact: refactor/consolidate object management, prepare for delayed free

debugobjects allocates static reference objects to track objects which
are initialized or activated before the slab cache becomes
available. These static reference objects have to be handled
seperately in free_object(). The handling of these objects is in the
way of implementing a delayed free functionality. The delayed free is
required to avoid callbacks into the mm code from
debug_check_no_obj_freed().

Replace the static object references with dynamic ones after the slab
cache has been initialized. The static objects are now marked initdata.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
LKML-Reference: <200903162049.58058.nickpiggin@yahoo.com.au>

While trying to debug why my Atom netbook is falling over booting
rawhide debug-enabled kernels, I stumbled across the fact that we've
been enabling object debugging by default. However, once you default it
to on, you've got no way to turn it back off again at runtime.

Add a boolean toggle to turn it off. I would just make it an int
module_param, however people may already expect the boolean enable
behaviour, so just add an analogue for disabling.
Signed-off-by: Kyle McMartin <kyle@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging-2.6:
  Staging: w35und: fix usb_control_msg() error handling in wb35_probe()
  Staging: w35und: fix registration with wlan stack
  Staging: panel: fix oops on panel_cleanup_module
  Staging: rtl8187se: Fix oops and memory poison caused by builtin ieee80211.
  Staging: rtl8187se: fix Kconfig dependencies

* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6: (21 commits)
  USB: musb: fix srp sysfs entry deletion
  USB: musb: resume suspended root hub on disconnect
  USB: musb: use right poll limit for low speed devices
  USB: musb: be careful with 64K+ transfer lengths, host side
  USB: musb: fix data toggle saving with shared FIFO
  USB: musb: host endpoint_disable() oops fixes
  USB: musb: fix urb_dequeue() method
  USB: musb: fix musb_host_tx() for shared endpoint FIFO
  USB: musb: be careful with 64K+ transfer lengths (gadget side)
  usb: musb: make Davinci *work* in mainline
  USB: usb_get_string should check the descriptor type
  USB: gadget: fix build error in omap_apollon_2420_defconfig
  USB: g_file_storage: automatically disable stalls under Atmel
  USB: usb-storage: add IGNORE_RESIDUE flag for Genesys Logic adapters
  USB: Quirk for Hummingbird huc56s / Conexant ACM modem
  USB: serial: add support for second revision of Ericsson F3507G WWAN card
  USB: cdc-acm: add usb id for motomagx phones
  USB: option: add BenQ 3g modem information
  usb: gadget: obex: select correct ep descriptors
  USB: EHCI: slow down ITD reuse
  ...

* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus:
  Revert "MIPS: Print irq handler description"
  MIPS: CVE-2009-0029: Enable syscall wrappers.
  MIPS: Alchemy: In plat_time_init() t reaches -1, tested: 0
  MIPS: Only allow Cavium OCTEON to be configured for boards that support it

Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86: enable DMAR by default
  xen: disable interrupts early, as start_kernel expects
  gpu/drm, x86, PAT: io_mapping_create_wc and resource_size_t
  gpu/drm, x86, PAT: Handle io_mapping_create_wc() errors in a clean way
  x86, Voyager: fix compile by lifting the degeneracy of phys_cpu_present_map
  x86, doc: fix references to Documentation/x86/i386/boot.txt

* 'sh/for-2.6.29' of git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6:
  sh: ap325rxa: Revert ov772x support.
  serial: sh-sci: fix overrun error handling for SH7785 SCIF.
  sh: Storage class should be before const qualifier

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6:
  V4L/DVB (10696): Remove outdated README for the flexcop-driver
  V4L/DVB (10695): Update Technisat card documentation
  V4L/DVB (10694): [PATCH] software IRQ watchdog for Flexcop B2C2 DVB PCI cards
  V4L/DVB (10663): soc-camera: fix S_CROP breakage on PXA and SuperH
  V4L/DVB (10659): em28xx: register device to soundcard for sysfs

Commit 8e961870 removed the FREEZE/THAW
handling in xfs_compat_ioctl but never added any compat handler back, so
now any freeze/thaw request from a 32-bit binary ond 64-bit userspace
will fail.

As these ioctls are 32/64-bit compatible two simple COMPATIBLE_IOCTL
entries in fs/compat_ioctl.c will do the job.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Future iLO devices will have an HP vendor id.
Signed-off-by: David Altobelli <david.altobelli@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Add __ref as a sparse modifier.
Signed-off-by: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

We should allow testing of all modifiers not just attributes.  Extend
testing and test for all the know modifiers.
Signed-off-by: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

We must make sure we do not misrecognise a modifier as an Identifier
when trying to match types.  Prevent us matching this:

	void * __ref
Signed-off-by: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

We may have any modifier following a pointer type star.  Handle this:

	void * __user * __user foo;
Signed-off-by: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

We need to handle interspersed modifiers in the middle of pointer types,
for example:

	void * __user * __user bar;
Signed-off-by: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

We are triggering the -p0 check for our own diffs generated using --file
command line option.  Suppress this check for files.
Signed-off-by: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

We say that in_atomic() is ok in the core kernel, but then always report
it regardless of where in the kernel it is.  Keep quiet if it is used in
kernel/*.
Signed-off-by: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

I just got this new warning from kmemcheck:

    WARNING: kmemcheck: Caught 32-bit read from freed memory (c7806a60)
    a06a80c7ecde70c1a04080c700000000a06709c1000000000000000000000000
     f f f f f f f f f f f f f f f f f f f f f f f f f f f f f f f f
     ^

    Pid: 0, comm: swapper Not tainted (2.6.29-rc4 #230)
    EIP: 0060:[<c1096df7>] EFLAGS: 00000286 CPU: 0
    EIP is at __purge_vmap_area_lazy+0x117/0x140
    EAX: 00070f43 EBX: c7806a40 ECX: c1677080 EDX: 00027b66
    ESI: 00002001 EDI: c170df0c EBP: c170df00 ESP: c178830c
     DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068
    CR0: 80050033 CR2: c7806b14 CR3: 01775000 CR4: 00000690
    DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000
    DR6: 00004000 DR7: 00000000
     [<c1096f3e>] free_unmap_vmap_area_noflush+0x6e/0x70
     [<c1096f6a>] remove_vm_area+0x2a/0x70
     [<c1097025>] __vunmap+0x45/0xe0
     [<c10970de>] vunmap+0x1e/0x30
     [<c1008ba5>] text_poke+0x95/0x150
     [<c1008ca9>] alternatives_smp_unlock+0x49/0x60
     [<c171ef47>] alternative_instructions+0x11b/0x124
     [<c171f991>] check_bugs+0xbd/0xdc
     [<c17148c5>] start_kernel+0x2ed/0x360
     [<c171409e>] __init_begin+0x9e/0xa9
     [<ffffffff>] 0xffffffff

It happened here:

    $ addr2line -e vmlinux -i c1096df7
    mm/vmalloc.c:540

Code:

	list_for_each_entry(va, &valist, purge_list)
		__free_vmap_area(va);

It's this instruction:

    mov    0x20(%ebx),%edx

Which corresponds to a dereference of va->purge_list.next:

    (gdb) p ((struct vmap_area *) 0)->purge_list.next
    Cannot access memory at address 0x20

It seems that we should use "safe" list traversal here, as the element
is freed inside the loop. Please verify that this is the right fix.
Acked-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: <stable@kernel.org>		[2.6.28.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The new vmap allocator can wrap the address and get confused in the case
of large allocations or VMALLOC_END near the end of address space.

Problem reported by Christoph Hellwig on a 32-bit XFS workload.
Signed-off-by: Nick Piggin <npiggin@suse.de>
Reported-by: Christoph Hellwig <hch@lst.de>
Cc: <stable@kernel.org>		[2.6.28.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

free_uid() and free_user_ns() are corecursive when CONFIG_USER_SCHED=n,
but free_user_ns() is called from free_uid() by way of uid_hash_remove(),
which requires uidhash_lock to be held.  free_user_ns() then calls
free_uid() to complete the destruction.

Fix this by deferring the destruction of the user_namespace.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: Herton Ronaldo Krzesinski <herton@mandriva.com.br>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Commit 4ea3ada2 declares d_obtain_alias()
as EXPORT_SYMBOL_GPL where it's supposed to replace d_alloc_anon which was
previously declared as EXPORT_SYMBOL and thus available to any loadable
module.

This patch reverts that.
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The w1_ds2433 driver does not read from the hardware if the CRC was valid
on the last read.  The validcrc flag should be cleared after a write so
that the new value can be read.
Signed-off-by: Ben Gardner <gardner.ben@gmail.com>
Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The SRP sysfs attribute is dependent on gadget mode; any
gadget may support SRP.  But "rmmod musb_hdrc" didn't
remove that attribute; fix.
Signed-off-by: Vikram Pandita <vikram.pandita@ti.com>
Acked-by: Felipe Balbi <me@felipebalbi.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

If this is not done, khubd will not be informed of the disconnect
and will assume the device is still there.

Easily seen when a hub is connected with no device attached to it;
it will autosuspend.  When the hub is disconnected, it still shows
up in /proc/bus/usb/devices
Signed-off-by: Anand Gadiyar <gadiyar@ti.com>
Acked-by: Felipe Balbi <felipe.balbi@nokia.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Remove wrongly applied upper limit on the interrupt transfer
interval for low speed devices (not much of an error per se,
according to USB specs).
Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Feeding 32-bit length cast down to 'u16' to min() to calculate the FIFO
count in musb_host_tx() risks sending a short packet prematurely for
transfer sizes over 64 KB.

Similarly, although data transfer size shouldn't exceed 65535 bytes for
the control endpoint, making musb_h_ep0_continue() more robust WRT URBs
with possibly oversized buffer will not hurt either...
Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Felipe Balbi <felipe.balbi@nokia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

For some strange reason the host side musb_giveback() decides
that it's always got an IN transfer when the hardware endpoint
is using a shared FIFO.  This causes musb_save_toggle() to read
the toggle state from the RXCSR register instead of TXCSR, and
may also cause unneeded reloading of RX endpoint registers.
Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

The musb_h_disable() routine can oops in some cases:

 - It's not safe to read hep->hcpriv outside musb->lock,
   since it gets changed on completion IRQ paths.

 - The list iterators aren't safe to use in that way;
   just remove the first element while !list_empty(),
   so deletions on other code paths can't make trouble.

We need two "scrub the list" loops because only one branch
should touch hardware and advance the schedule.

[ dbrownell@users.sourceforge.net: massively simplify
  patch description; add key points as code comments ]
Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

The urb_dequeue() method forgets to unlink 'struct musb_qh' from the
control or bulk schedules when the URB being cancelled is the only
one queued to its endpoint.  That will cause musb_advance_schedule()
to block once it reaches 'struct musb_qh' with now empty URB list, so
URBs queued for other endpoints after the one being dequeued will not
be served.

Fix by unlinking the QH from the list except when it's already being
handled (typically by musb_giveback).  Since a QH with an empty URB
list is now supposed to be freed, do that.  And remove a now-useless
check from musb_advance_schedule().

[ dbrownell@users.sourceforge.net: update patch description,
  and fold in a dequeue() comment patch ]
Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Felipe Balbi <felipe.balbi@nokia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

The input queue should be used for TX on endpoints which
share FIFO hardware.  The host TX path wasn't doing that.

Shared FIFOs are most often configured for periodic endpoints,
which are mostly used for RX/IN transfers ... that's probably
how this bug managed to linger for a long time.

[ dbrownell@users.sourceforge.net: update patch description ]
Signed-off-by: Dmitry Krivoschekov <dkrivoschekov@ru.mvista.com>
Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Acked-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Felipe Balbi <felipe.balbi@nokia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

request->actual is an unsigned and we should use the same
variable type for fifo_count otherwise we might lose some
data if request->length >= 64kbytes.

[ dbrownell@users.sourceforge.net: fix compiler warning ]
Signed-off-by: Felipe Balbi <felipe.balbi@nokia.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Now that the musb build fixes for DaVinci got merged (RC3?), kick in
the other bits needed to get it finally *working* in mainline:

 - Use clk_enable()/clk_disable() ... the "always enable USB clocks"
   code this originally relied on has since been removed.

 - Initialize the USB device only after the relevant I2C GPIOs are
   available, so the host side can properly enable VBUS.

 - Tweak init sequencing to cope with mainline's relatively late init
   of the I2C system bus for power switches, transceivers, and so on.

Sanity tested on DM6664 EVM for host and peripheral modes; that system
won't boot with CONFIG_PM enabled, so OTG can't yet be tested.  Also
verified on OMAP3.

(Unrelated:  correct the MODULE_PARM_DESC spelling of musb_debug.)
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Felipe Balbi <me@felipebalbi.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

This patch (as1218) fixes a problem with a radio-control joystick used
in the "walkera 4#3" helicopter.  This device responds to the initial
Get-String-Descriptor request for string 0 (which is really the list
of supported languages) by sending its config descriptor!  The
usb_get_string() routine needs to check whether it got the right
type of descriptor.

Oddly enough, this sort of check is already present in
usb_get_descriptor().  The patch changes the error code from -EPROTO
to -ENODATA, because -EPROTO shows up in so many other contexts to
indicate a hardware failure rather than a firmware error.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Guillermo Jarabo <williamjap@gmail.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

===================================================================

In apollon case, it only used udc, so udc configuration should select
USB_OTG_UTILS also.
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

This patch (as1220) automatically disables stalls when g_file_storage
finds itself running with an Atmel device controller, because the
Atmel hardware/driver isn't capable of halting bulk endpoints
correctly.
Reported-by: Stanislaw Gruszka <stf_xl@wp.pl>
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

This patch (as1219) adds the IGNORE_RESIDUE flag to the unusual_devs
entries for Genesys Logic's USB-IDE adapter.  Although this device
usually gets the residue correct, there is one command crucial to the
operation of CD and DVD drives which it messes up.
Tested-by: Mike Lampard <mike@mtgambier.net>
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Signed-off-by: Adam J. Richter <adam_richter2004@yahoo.com>
Cc: Oliver Neukum <oliver@neukum.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>