Commit Graph

299229 Commits

Author SHA1 Message Date
Konrad Rzeszutek Wilk
b7e5ffe5d8 xen/pte: Fix crashes when trying to see non-existent PGD/PMD/PUD/PTEs
If I try to do "cat /sys/kernel/debug/kernel_page_tables"
I end up with:

BUG: unable to handle kernel paging request at ffffc7fffffff000
IP: [<ffffffff8106aa51>] ptdump_show+0x221/0x480
PGD 0
Oops: 0000 [#1] SMP
CPU 0
.. snip..
RAX: 0000000000000000 RBX: ffffc00000000fff RCX: 0000000000000000
RDX: 0000800000000000 RSI: 0000000000000000 RDI: ffffc7fffffff000

which is due to the fact we are trying to access a PFN that is not
accessible to us. The reason (at least in this case) was that
PGD[256] is set to __HYPERVISOR_VIRT_START which was setup (by the
hypervisor) to point to a read-only linear map of the MFN->PFN array.
During our parsing we would get the MFN (a valid one), try to look
it up in the MFN->PFN tree and find it invalid and return ~0 as PFN.
Then pte_mfn_to_pfn would happilly feed that in, attach the flags
and return it back to the caller. 'ptdump_show' bitshifts it and
gets and invalid value that it tries to dereference.

Instead of doing all of that, we detect the ~0 case and just
return !_PAGE_PRESENT.

This bug has been in existence .. at least until 2.6.37 (yikes!)

CC: stable@kernel.org
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-05-07 10:21:13 -04:00
Konrad Rzeszutek Wilk
558daa289a xen/apic: Return the APIC ID (and version) for CPU 0.
On x86_64 on AMD machines where the first APIC_ID is not zero, we get:

ACPI: LAPIC (acpi_id[0x01] lapic_id[0x10] enabled)
BIOS bug: APIC version is 0 for CPU 1/0x10, fixing up to 0x10
BIOS bug: APIC version mismatch, boot CPU: 0, CPU 1: version 10

which means that when the ACPI processor driver loads and
tries to parse the _Pxx states it fails to do as, as it
ends up calling acpi_get_cpuid which does this:

for_each_possible_cpu(i) {
        if (cpu_physical_id(i) == apic_id)
                return i;
}

And the bootup CPU, has not been found so it fails and returns -1
for the first CPU - which then subsequently in the loop that
"acpi_processor_get_info" does results in returning an error, which
means that "acpi_processor_add" failing and per_cpu(processor)
is never set (and is NULL).

That means that when xen-acpi-processor tries to load (much much
later on) and parse the P-states it gets -ENODEV from
acpi_processor_register_performance() (which tries to read
the per_cpu(processor)) and fails to parse the data.

Reported-by-and-Tested-by:  Stefan Bader <stefan.bader@canonical.com>
Suggested-by:  Boris Ostrovsky <boris.ostrovsky@amd.com>
[v2: Bit-shift APIC ID by 24 bits]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-05-07 10:18:47 -04:00
Julia Lawall
a7a97c6394 drivers/video/xen-fbfront.c: add missing cleanup code
The operations in the subsequent error-handling code appear to be also
useful here.

Acked-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
[v1: Collapse some of the error handling functions]
[v2: Fix compile warning]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-05-07 06:41:56 -04:00
David Vrabel
7eb7ce4d2e xen: correctly check for pending events when restoring irq flags
In xen_restore_fl_direct(), xen_force_evtchn_callback() was being
called even if no events were pending.  This resulted in (depending on
workload) about a 100 times as many xen_version hypercalls as
necessary.

Fix this by correcting the sense of the conditional jump.

This seems to give a significant performance benefit for some
workloads.

There is some subtle tricksy "..since the check here is trying to
check both pending and masked in a single cmpw, but I think this is
correct. It will call check_events now only when the combined
mask+pending word is 0x0001 (aka unmasked, pending)." (Ian)

CC: stable@kernel.org
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-04-27 16:04:21 -04:00
Konrad Rzeszutek Wilk
b930fe5e1f xen/acpi: Workaround broken BIOSes exporting non-existing C-states.
We did a similar check for the P-states but did not do it for
the C-states. What we want to do is ignore cases where the DSDT
has definition for sixteen CPUs, but the machine only has eight
CPUs and we get:
xen-acpi-processor: (CX): Hypervisor error (-22) for ACPI CPU14

Reported-by: Tobias Geiger <tobias.geiger@vido.info>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-04-26 22:07:28 -04:00
Konrad Rzeszutek Wilk
cf405ae612 xen/smp: Fix crash when booting with ACPI hotplug CPUs.
When we boot on a machine that can hotplug CPUs and we
are using 'dom0_max_vcpus=X' on the Xen hypervisor line
to clip the amount of CPUs available to the initial domain,
we get this:

(XEN) Command line: com1=115200,8n1 dom0_mem=8G noreboot dom0_max_vcpus=8 sync_console mce_verbosity=verbose console=com1,vga loglvl=all guest_loglvl=all
.. snip..
DMI: Intel Corporation S2600CP/S2600CP, BIOS SE5C600.86B.99.99.x032.072520111118 07/25/2011
.. snip.
SMP: Allowing 64 CPUs, 32 hotplug CPUs
installing Xen timer for CPU 7
cpu 7 spinlock event irq 361
NMI watchdog: disabled (cpu7): hardware events not enabled
Brought up 8 CPUs
.. snip..
	[acpi processor finds the CPUs are not initialized and starts calling
	arch_register_cpu, which creates /sys/devices/system/cpu/cpu8/online]
CPU 8 got hotplugged
CPU 9 got hotplugged
CPU 10 got hotplugged
.. snip..
initcall 1_acpi_battery_init_async+0x0/0x1b returned 0 after 406 usecs
calling  erst_init+0x0/0x2bb @ 1

	[and the scheduler sticks newly started tasks on the new CPUs, but
	said CPUs cannot be initialized b/c the hypervisor has limited the
	amount of vCPUS to 8 - as per the dom0_max_vcpus=8 flag.
	The spinlock tries to kick the other CPU, but the structure for that
	is not initialized and we crash.]
BUG: unable to handle kernel paging request at fffffffffffffed8
IP: [<ffffffff81035289>] xen_spin_lock+0x29/0x60
PGD 180d067 PUD 180e067 PMD 0
Oops: 0002 [#1] SMP
CPU 7
Modules linked in:

Pid: 1, comm: swapper/0 Not tainted 3.4.0-rc2upstream-00001-gf5154e8 #1 Intel Corporation S2600CP/S2600CP
RIP: e030:[<ffffffff81035289>]  [<ffffffff81035289>] xen_spin_lock+0x29/0x60
RSP: e02b:ffff8801fb9b3a70  EFLAGS: 00010282

With this patch, we cap the amount of vCPUS that the initial domain
can run, to exactly what dom0_max_vcpus=X has specified.

In the future, if there is a hypercall that will allow a running
domain to expand past its initial set of vCPUS, this patch should
be re-evaluated.

CC: stable@kernel.org
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-04-26 22:07:21 -04:00
Stefano Stabellini
521394e4e6 xen: use the pirq number to check the pirq_eoi_map
In pirq_check_eoi_map use the pirq number rather than the Linux irq
number to check whether an eoi is needed in the pirq_eoi_map.

The reason is that the irq number is not always identical to the
pirq number so if we wrongly use the irq number to check the
pirq_eoi_map we are going to check for the wrong pirq to EOI.

As a consequence some interrupts might not be EOI'ed by the
guest correctly.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Tested-by: Tobias Geiger <tobias.geiger@vido.info>
[v1: Added some extra wording to git commit]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-04-26 18:02:02 -04:00
Konrad Rzeszutek Wilk
df88b2d96e xen/enlighten: Disable MWAIT_LEAF so that acpi-pad won't be loaded.
There are exactly four users of __monitor and __mwait:

 - cstate.c (which allows acpi_processor_ffh_cstate_enter to be called
   when the cpuidle API drivers are used. However patch
   "cpuidle: replace xen access to x86 pm_idle and default_idle"
   provides a mechanism to disable the cpuidle and use safe_halt.
 - smpboot (which allows mwait_play_dead to be called). However
   safe_halt is always used so we skip that.
 - intel_idle (same deal as above).
 - acpi_pad.c. This the one that we do not want to run as we
   will hit the below crash.

Why do we want to expose MWAIT_LEAF in the first place?
We want it for the xen-acpi-processor driver - which uploads
C-states to the hypervisor. If MWAIT_LEAF is set, the cstate.c
sets the proper address in the C-states so that the hypervisor
can benefit from using the MWAIT functionality. And that is
the sole reason for using it.

Without this patch, if a module performs mwait or monitor we
get this:

invalid opcode: 0000 [#1] SMP
CPU 2
.. snip..
Pid: 5036, comm: insmod Tainted: G           O 3.4.0-rc2upstream-dirty #2 Intel Corporation S2600CP/S2600CP
RIP: e030:[<ffffffffa000a017>]  [<ffffffffa000a017>] mwait_check_init+0x17/0x1000 [mwait_check]
RSP: e02b:ffff8801c298bf18  EFLAGS: 00010282
RAX: ffff8801c298a010 RBX: ffffffffa03b2000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffff8801c29800d8 RDI: ffff8801ff097200
RBP: ffff8801c298bf18 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000
R13: ffffffffa000a000 R14: 0000005148db7294 R15: 0000000000000003
FS:  00007fbb364f2700(0000) GS:ffff8801ff08c000(0000) knlGS:0000000000000000
CS:  e033 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 000000000179f038 CR3: 00000001c9469000 CR4: 0000000000002660
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process insmod (pid: 5036, threadinfo ffff8801c298a000, task ffff8801c29cd7e0)
Stack:
 ffff8801c298bf48 ffffffff81002124 ffffffffa03b2000 00000000000081fd
 000000000178f010 000000000178f030 ffff8801c298bf78 ffffffff810c41e6
 00007fff3fb30db9 00007fff3fb30db9 00000000000081fd 0000000000010000
Call Trace:
 [<ffffffff81002124>] do_one_initcall+0x124/0x170
 [<ffffffff810c41e6>] sys_init_module+0xc6/0x220
 [<ffffffff815b15b9>] system_call_fastpath+0x16/0x1b
Code: <0f> 01 c8 31 c0 0f 01 c9 c9 c3 00 00 00 00 00 00 00 00 00 00 00 00
RIP  [<ffffffffa000a017>] mwait_check_init+0x17/0x1000 [mwait_check]
 RSP <ffff8801c298bf18>
---[ end trace 16582fc8a3d1e29a ]---
Kernel panic - not syncing: Fatal exception

With this module (which is what acpi_pad.c would hit):

MODULE_AUTHOR("Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>");
MODULE_DESCRIPTION("mwait_check_and_back");
MODULE_LICENSE("GPL");
MODULE_VERSION();

static int __init mwait_check_init(void)
{
	__monitor((void *)&current_thread_info()->flags, 0, 0);
	__mwait(0, 0);
	return 0;
}
static void __exit mwait_check_exit(void)
{
}
module_init(mwait_check_init);
module_exit(mwait_check_exit);

Reported-by: Liu, Jinsong <jinsong.liu@intel.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-04-26 17:46:20 -04:00
Konrad Rzeszutek Wilk
3d81acb1cd Revert "xen/p2m: m2p_find_override: use list_for_each_entry_safe"
This reverts commit b960d6c43a.

If we have another thread (very likely) touched the list, we
end up hitting a problem "that the next element is wrong because
we should be able to cope with that. The problem is that the
next->next pointer would be set LIST_POISON1. " (Stefano's
comment on the patch).

Reverting for now.

Suggested-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-04-20 11:56:00 -04:00
Konrad Rzeszutek Wilk
186bab1ce0 xen/resume: Fix compile warnings.
linux/drivers/xen/manage.c: In function 'do_suspend':
linux/drivers/xen/manage.c:160:5: warning: 'si.cancelled' may be used uninitialized in this function

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-04-19 15:12:49 -04:00
Konrad Rzeszutek Wilk
3066616ce2 xen/xenbus: Add quirk to deal with misconfigured backends.
A rather annoying and common case is when booting a PVonHVM guest
and exposing the PV KBD and PV VFB - as broken toolstacks don't
always initialize the backends correctly.

Normally The HVM guest is using the VGA driver and the emulated
keyboard for this (though upstream version of QEMU implements
PV KBD, but still uses a VGA driver). We provide a very basic
two-stage wait mechanism - where we wait for 30 seconds for all
devices, and then for 270 for all them except the two mentioned.

That allows us to wait for the essential devices, like network
or disk for the full 6 minutes.

To trigger this, put this in your guest config:

vfb = [ 'vnc=1, vnclisten=0.0.0.0 ,vncunused=1']

instead of this:
vnc=1
vnclisten="0.0.0.0"

CC: stable@kernel.org
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
[v3: Split delay in non-essential (30 seconds) and essential
 devices per Ian and Stefano suggestion]
[v4: Added comments per Stefano suggestion]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-04-19 12:45:01 -04:00
Konrad Rzeszutek Wilk
a71e23d992 xen/blkback: Fix warning error.
drivers/block/xen-blkback/xenbus.c: In function 'xen_blkbk_discard':
drivers/block/xen-blkback/xenbus.c:419:4: warning: passing argument 1 of 'dev_warn' makes pointer from integer without a cast
+[enabled by default]
include/linux/device.h:894:5: note: expected 'const struct device *' but argument is of type 'long int'

It is unclear how that mistake made it in. It surely is wrong.

Acked-by: Jens Axboe <axboe@kernel.dk>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-04-18 15:54:08 -04:00
Konrad Rzeszutek Wilk
681e4a5e13 Merge commit 'c104f1fa1ecf4ee0fc06e31b1f77630b2551be81' into stable/for-linus-3.4
* commit 'c104f1fa1ecf4ee0fc06e31b1f77630b2551be81': (14566 commits)
  cpufreq: OMAP: fix build errors: depends on ARCH_OMAP2PLUS
  sparc64: Eliminate obsolete __handle_softirq() function
  sparc64: Fix bootup crash on sun4v.
  kconfig: delete last traces of __enabled_ from autoconf.h
  Revert "kconfig: fix __enabled_ macros definition for invisible and un-selected symbols"
  kconfig: fix IS_ENABLED to not require all options to be defined
  irq_domain: fix type mismatch in debugfs output format
  staging: android: fix mem leaks in __persistent_ram_init()
  staging: vt6656: Don't leak memory in drivers/staging/vt6656/ioctl.c::private_ioctl()
  staging: iio: hmc5843: Fix crash in probe function.
  panic: fix stack dump print on direct call to panic()
  drivers/rtc/rtc-pl031.c: enable clock on all ST variants
  Revert "mm: vmscan: fix misused nr_reclaimed in shrink_mem_cgroup_zone()"
  hugetlb: fix race condition in hugetlb_fault()
  drivers/rtc/rtc-twl.c: use static register while reading time
  drivers/rtc/rtc-s3c.c: add placeholder for driver private data
  drivers/rtc/rtc-s3c.c: fix compilation error
  MAINTAINERS: add PCDP console maintainer
  memcg: do not open code accesses to res_counter members
  drivers/rtc/rtc-efi.c: fix section mismatch warning
  ...
2012-04-18 15:52:50 -04:00
Stefano Stabellini
b960d6c43a xen/p2m: m2p_find_override: use list_for_each_entry_safe
Use list_for_each_entry_safe and remove the spin_lock acquisition in
m2p_find_override.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-04-17 13:27:28 -04:00
Stefano Stabellini
e8e937be97 xen/gntdev: do not set VM_PFNMAP
Since we are using the m2p_override we do have struct pages
corresponding to the user vma mmap'ed by gntdev.

Removing the VM_PFNMAP flag makes get_user_pages work on that vma.
An example test case would be using a Xen userspace block backend
(QDISK) on a file on NFS using O_DIRECT.

CC: stable@kernel.org
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-04-17 13:27:17 -04:00
Julia Lawall
6b5e7d9ef7 xen/grant-table: add error-handling code on failure of gnttab_resume
Jump to the label ini_nomem as done on the failure of the page allocations
above.

The code at ini_nomem is modified to accommodate different return values.

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-04-17 00:29:32 -04:00
Linus Torvalds
c104f1fa1e Merge branch 'for-3.4/drivers' of git://git.kernel.dk/linux-block
Pull block driver bits from Jens Axboe:

 - A series of fixes for mtip32xx.  Most from Asai at Micron, but also
   one from Greg, getting rid of the dependency on PCIE_HOTPLUG.

 - A few bug fixes for xen-blkfront, and blkback.

 - A virtio-blk fix for Vivek, making resize actually work.

 - Two fixes from Stephen, making larger transfers possible on cciss.
   This is needed for tape drive support.

* 'for-3.4/drivers' of git://git.kernel.dk/linux-block:
  block: mtip32xx: remove HOTPLUG_PCI_PCIE dependancy
  mtip32xx: dump tagmap on failure
  mtip32xx: fix handling of commands in various scenarios
  mtip32xx: Shorten macro names
  mtip32xx: misc changes
  mtip32xx: Add new sysfs entry 'status'
  mtip32xx: make setting comp_time as common
  mtip32xx: Add new bitwise flag 'dd_flag'
  mtip32xx: fix error handling in mtip_init()
  virtio-blk: Call revalidate_disk() upon online disk resize
  xen/blkback: Make optional features be really optional.
  xen/blkback: Squash the discard support for 'file' and 'phy' type.
  mtip32xx: fix incorrect value set for drv_cleanup_done, and re-initialize and start port in mtip_restart_port()
  cciss: Fix scsi tape io with more than 255 scatter gather elements
  cciss: Initialize scsi host max_sectors for tape drive support
  xen-blkfront: make blkif_io_lock spinlock per-device
  xen/blkfront: don't put bdev right after getting it
  xen-blkfront: use bitmap_set() and bitmap_clear()
  xen/blkback: Enable blkback on HVM guests
  xen/blkback: use grant-table.c hypercall wrappers
2012-04-13 18:45:13 -07:00
Linus Torvalds
d8dd0b6d48 Merge branch 'for-3.4/core' of git://git.kernel.dk/linux-block
Pull block core bits from Jens Axboe:
 "It's a nice and quiet round this time, since most of the tricky stuff
  has been pushed to 3.5 to give it more time to mature.  After a few
  hectic block IO core changes for 3.3 and 3.2, I'm quite happy with a
  slow round.

  Really minor stuff in here, the only real functional change is making
  the auto-unplug threshold a per-queue entity.  The threshold is set so
  that it's low enough that we don't hold off IO for too long, but still
  big enough to get a nice benefit from the batched insert (and hence
  queue lock cost reduction).  For raid configurations, this currently
  breaks down."

* 'for-3.4/core' of git://git.kernel.dk/linux-block:
  block: make auto block plug flush threshold per-disk based
  Documentation: Add sysfs ABI change for cfq's target latency.
  block: Make cfq_target_latency tunable through sysfs.
  block: use lockdep_assert_held for queue locking
  block: blk_alloc_queue_node(): use caller's GFP flags instead of GFP_KERNEL
2012-04-13 18:07:19 -07:00
Kevin Hilman
2d59dcfb54 cpufreq: OMAP: fix build errors: depends on ARCH_OMAP2PLUS
The OMAP driver needs a 'depends on ARCH_OMAP2PLUS' since it only
builds for OMAP2+ platforms.

This 'depends on' was in the original patch from Russell King, but was
erroneously removed by me when making this option user-selectable in
commit b09db45c (cpufreq: OMAP driver depends CPUfreq tables.)  This
patch remedies that.

Apologies to Russell King for breaking his originally working patch.

Also, thanks to Grazvydas Ignotas for reporting the same problem.

Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Grazvydas Ignotas <notasas@gmail.com>
Signed-off-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-04-13 17:57:40 -07:00
Linus Torvalds
7d93101fc7 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc
Pull sparc fixes from David Miller.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  sparc64: Eliminate obsolete __handle_softirq() function
  sparc64: Fix bootup crash on sun4v.
2012-04-13 12:41:21 -07:00
Linus Torvalds
6e1173399d hwmon patches for 3.4-rc3
Fix build warnings in four drivers
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Merge tag 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging

Pull hwmon patches from Guenter Roeck:
 "Fix build warnings in four drivers"

* tag 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
  hwmon: (pmbus_core) Fix compiler warning
  hwmon: (smsc47m1) Fix compiler warning
  hwmon: (acpi_power_meter) Fix compiler warning seen in some configurations
  hwmon: (smsc47b397) Fix compiler warning
2012-04-13 12:19:41 -07:00
Linus Torvalds
461c14917e GPIO bug fixes on top of v3.4-rc2
Miscellaneous bug fixes to GPIO drivers and for a corner case in the
 gpio device tree parsing code.
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Merge tag 'gpio-for-linus' of git://git.secretlab.ca/git/linux-2.6

Pull GPIO bug fixes from Grant Likely:
 "Miscellaneous bug fixes to GPIO drivers and for a corner case in the
  gpio device tree parsing code."

* tag 'gpio-for-linus' of git://git.secretlab.ca/git/linux-2.6:
  gpio/exynos: Fix compiler warning in gpio-samsung.c file
  gpio: Fix range check in of_gpio_simple_xlate()
  gpio: Fix uninitialized variable bit in adp5588_irq_handler
  gpio/sodaville: Convert sodaville driver to new irqdomain API
2012-04-13 12:18:20 -07:00
Linus Torvalds
cf7d8a5550 SPI bug fixes on top of v3.4-rc2
Miscellaneous driver bug fixes.  No major changes in this branch.
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Merge tag 'spi-for-linus' of git://git.secretlab.ca/git/linux-2.6

Pull SPI bug fixes from Grant Likely:
 "Miscellaneous driver bug fixes.  No major changes in this branch."

* tag 'spi-for-linus' of git://git.secretlab.ca/git/linux-2.6:
  spi/imx: prevent NULL pointer dereference in spi_imx_probe()
  spi/imx: mark base member in spi_imx_data as __iomem
  spi/mpc83xx: fix NULL pdata dereference bug
  spi/davinci: Fix DMA API usage in davinci
  spi/pL022: include types.h to remove compilation warnings
2012-04-13 12:17:45 -07:00
Paul E. McKenney
3d3eeb2ef2 sparc64: Eliminate obsolete __handle_softirq() function
The invocation of softirq is now handled by irq_exit(), so there is no
need for sparc64 to invoke it on the trap-return path.  In fact, doing so
is a bug because if the trap occurred in the idle loop, this invocation
can result in lockdep-RCU failures.  The problem is that RCU ignores idle
CPUs, and the sparc64 trap-return path to the softirq handlers fails to
tell RCU that the CPU must be considered non-idle while those handlers
are executing.  This means that RCU is ignoring any RCU read-side critical
sections in those handlers, which in turn means that RCU-protected data
can be yanked out from under those read-side critical sections.

The shiny new lockdep-RCU ability to detect RCU read-side critical sections
that RCU is ignoring located this problem.

The fix is straightforward: Make sparc64 stop manually invoking the
softirq handlers.

Reported-by: Meelis Roos <mroos@linux.ee>
Suggested-by: David Miller <davem@davemloft.net>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Meelis Roos <mroos@linux.ee>
Cc: stable@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-13 11:58:38 -07:00
David S. Miller
9e0daff30f sparc64: Fix bootup crash on sun4v.
The DS driver registers as a subsys_initcall() but this can be too
early, in particular this risks registering before we've had a chance
to allocate and setup module_kset in kernel/params.c which is
performed also as a subsyts_initcall().

Register DS using device_initcall() insteal.

Signed-off-by: David S. Miller <davem@davemloft.net>
Cc: stable@vger.kernel.org
2012-04-13 11:56:22 -07:00
Linus Torvalds
4166fb6459 Add a fix for a bug hit by Alexey Shvetsov in ib_srtp that hits on
non-mlx4 hardware.
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Merge tag 'srpt-srq-type' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband

Pull infiniband fix from Roland Dreier:
 "Add a fix for a bug hit by Alexey Shvetsov in ib_srtp that hits on
  non-mlx4 hardware."

* tag 'srpt-srq-type' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband:
  IB/srpt: Set srq_type to IB_SRQT_BASIC
2012-04-12 18:51:32 -07:00
Paul Gortmaker
e4757cab4c kconfig: delete last traces of __enabled_ from autoconf.h
We've now fixed IS_ENABLED() and friends to not require any special
"__enabled_" prefixed versions of the normal Kconfig options, so delete
the last traces of them being generated.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-04-12 18:35:58 -07:00
Paul Gortmaker
a959613533 Revert "kconfig: fix __enabled_ macros definition for invisible and un-selected symbols"
This reverts commit 953742c8fe.

Dumping two lines into autoconf.h for all existing Kconfig options
results in a giant file (~16k lines) we have to process each time we
compile something.  We've weaned IS_ENABLED() and similar off of
requiring the __enabled_ definitions so now we can revert the change
which caused all the extra lines.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-04-12 18:35:58 -07:00
Paul Gortmaker
69349c2dc0 kconfig: fix IS_ENABLED to not require all options to be defined
Using IS_ENABLED() within C (vs.  within CPP #if statements) in its
current form requires us to actually define every possible bool/tristate
Kconfig option twice (__enabled_* and __enabled_*_MODULE variants).

This results in a huge autoconf.h file, on the order of 16k lines for a
x86_64 defconfig.

Fixing IS_ENABLED to be able to work on the smaller subset of just
things that we really have defined is step one to fixing this.  Which
means it has to not choke when fed non-enabled options, such as:

  include/linux/netdevice.h:964:1: warning: "__enabled_CONFIG_FCOE_MODULE" is not defined [-Wundef]

The original prototype of how to implement a C and preprocessor
compatible way of doing this came from the Google+ user "comex ." in
response to Linus' crowdsourcing challenge for a possible improvement on
his earlier C specific solution:

	#define config_enabled(x)       (__stringify(x)[0] == '1')

In this implementation, I've chosen variable names that hopefully make
how it works more understandable.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-04-12 18:35:58 -07:00
Linus Torvalds
7c427f4550 USB fixes for 3.4-rc2
Here are a number of fixes for the USB core and drivers for 3.4-rc2
 
 Lots of tiny xhci fixes here, a few usb-serial driver fixes and new device ids,
 and a smattering of other minor fixes in different USB drivers.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'usb-3.4-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb

Pull USB fixes from Greg KH:
 "Here are a number of fixes for the USB core and drivers for 3.4-rc2

  Lots of tiny xhci fixes here, a few usb-serial driver fixes and new
  device ids, and a smattering of other minor fixes in different USB
  drivers.

  Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"

* tag 'usb-3.4-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (30 commits)
  USB: update usbtmc api documentation
  xHCI: Correct the #define XHCI_LEGACY_DISABLE_SMI
  xHCI: use gfp flags from caller instead of GFP_ATOMIC
  xHCI: add XHCI_RESET_ON_RESUME quirk for VIA xHCI host
  USB: fix bug of device descriptor got from superspeed device
  xhci: Fix register save/restore order.
  xhci: Restore event ring dequeue pointer on resume.
  xhci: Don't write zeroed pointers to xHC registers.
  xhci: Warn when hosts don't halt.
  xhci: don't re-enable IE constantly
  usb: xhci: fix section mismatch in linux-next
  xHCI: correct to print the true HSEE of USBCMD
  USB: serial: fix race between probe and open
  UHCI: hub_status_data should indicate if ports are resuming
  EHCI: keep track of ports being resumed and indicate in hub_status_data
  USB: fix race between root-hub suspend and remote wakeup
  USB: sierra: add support for Sierra Wireless MC7710
  USB: ftdi_sio: fix race condition in TIOCMIWAIT, and abort of TIOCMIWAIT when the device is removed
  USB: ftdi_sio: fix status line change handling for TIOCMIWAIT and TIOCGICOUNT
  USB: don't ignore suspend errors for root hubs
  ...
2012-04-12 15:37:21 -07:00
Linus Torvalds
f4f9c1ac78 tty and serial fixes for 3.4-rc2
Here are some tty and serial fixes for 3.4-rc2.
 
 Most important here is the pl011 fix, which has been reported by about
 100 different people, which means more people use it than I expected :)
 
 There are also some 8250 driver reverts due to some problems reported by
 them.  And other minor fixes as well.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-3.4-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty and serial fixes from Greg KH:
 "Here are some tty and serial fixes for 3.4-rc2.

  Most important here is the pl011 fix, which has been reported by about
  100 different people, which means more people use it than I expected
  :)

  There are also some 8250 driver reverts due to some problems reported
  by them.  And other minor fixes as well.

  Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"

* tag 'tty-3.4-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  pch_uart: Add Kontron COMe-mTT10 uart clock quirk
  pch_uart: Fix MSI setting issue
  serial/8250_pci: add a "force background timer" flag and use it for the "kt" serial port
  Revert "serial/8250_pci: setup-quirk workaround for the kt serial controller"
  Revert "serial/8250_pci: init-quirk msi support for kt serial controller"
  tty/serial/omap: console can only be built-in
  serial: samsung: fix omission initialize ulcon in reset port fn()
  printk(): add KERN_CONT where needed in hpet and vt code
  tty/serial: atmel_serial: fix RS485 half-duplex problem
  tty: serial: altera_uart: Check for NULL platform_data in probe.
  isdn/gigaset: use gig_dbg() for debugging output
  omap-serial: Fix the error handling in the omap_serial probe
  serial: PL011: move interrupt clearing
2012-04-12 15:36:33 -07:00
Linus Torvalds
3dbc35a339 Staging tree fixes for 3.4-rc2
Here are a number of bugfixes for the drivers/staging/ portion of the kernel
 that have been reported recently.
 Nothing major here, with maybe the exception of the ramster code can now be
 built so it is enabled in the build again, and lots of memory leaks that people
 like to have fixed on their systems.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'staging-3.4-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging

Pull staging tree fixes from Greg KH:
 "Here are a number of bugfixes for the drivers/staging/ portion of the
  kernel that have been reported recently.

  Nothing major here, with maybe the exception of the ramster code can
  now be built so it is enabled in the build again, and lots of memory
  leaks that people like to have fixed on their systems.

  Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"

* tag 'staging-3.4-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
  staging: android: fix mem leaks in __persistent_ram_init()
  staging: vt6656: Don't leak memory in drivers/staging/vt6656/ioctl.c::private_ioctl()
  staging: iio: hmc5843: Fix crash in probe function.
  staging/xgifb: fix display on XGI Volari Z11m cards
  Staging: android: timed_gpio: Fix resource leak in timed_gpio_probe error paths
  android: make persistent_ram based drivers depend on HAVE_MEMBLOCK
  staging: iio: ak8975: Remove i2c client data corruption
  staging: drm/omap: move where DMM driver is registered
  staging: zsmalloc: fix memory leak
  Staging: rts_pstor: off by one in for loop
  staging: ozwpan: Added new maintainer for ozwpan
  staging:rts_pstor:Avoid "Bad target number" message when probing driver
  staging:rts_pstor:Fix possible panic by NULL pointer dereference
  Staging: vt6655-6: check keysize before memcpy()
  staging/media/as102: Don't call release_firmware() on uninitialized variable
  staging:iio:core add missing increment of loop index in iio_map_array_unregister()
  staging: ramster: unbreak my heart
  staging/vme: Fix module parameters
  staging: sep: Fix sign of error
2012-04-12 15:35:12 -07:00
Linus Torvalds
f5ad501006 Driver core and kobject fixes for 3.4-rc2
Here are some minor fixes for the driver core and kobjects that people have
 reported recently.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-3.4-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core and kobject fixes from Greg KH:
 "Here are some minor fixes for the driver core and kobjects that people
  have reported recently.

  Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"

* tag 'driver-core-3.4-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  kobject: provide more diagnostic info for kobject_add_internal() failures
  sysfs: handle 'parent deleted before child added'
  sysfs: Prevent crash on unset sysfs group attributes
  sysfs: Update the name hash for an entry after changing the namespace
  drivers/base: fix compiler warning in SoC export driver - idr should be ida
  drivers/base: Remove unneeded spin_lock_init call for soc_lock
2012-04-12 15:34:33 -07:00
Linus Torvalds
b3dfd76c94 irqdomain bug fixes for v3.4-rc3
Format string bug fix for irqdomain debug output on 64 bit platforms
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Merge tag 'irqdomain-for-linus' of git://git.secretlab.ca/git/linux-2.6

Pull a fix for the recent irqdomain bug fixes from Grant Likely:
 "I flubbed one patch in the last pull request which broke a format
  string on 64 bit platforms.  Here's the fix."

* tag 'irqdomain-for-linus' of git://git.secretlab.ca/git/linux-2.6:
  irq_domain: fix type mismatch in debugfs output format
2012-04-12 15:33:16 -07:00
Grant Likely
5269a9ab7d irq_domain: fix type mismatch in debugfs output format
sizeof(void*) returns an unsigned long, but it was being used as a width parameter to a "%-*s" format string which requires an int.  On 64 bit platforms this causes a type mismatch:

    linux/kernel/irq/irqdomain.c:575: warning: field width should have type
    'int', but argument 6 has type 'long unsigned int'

This change casts the size to an int so printf gets the right data type.

Reported-by: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: David Daney <david.daney@cavium.com>
2012-04-12 16:25:48 -06:00
Linus Torvalds
9b1ef1de20 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull trivial perf build failure fix from Thomas Gleixner.

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf tools: Fix getrusage() related build failure on glibc trunk
2012-04-12 15:20:24 -07:00
Linus Torvalds
ccb1ec95e9 Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fixes from Thomas Gleixner:
 "The itimer removal one is not strictly a fix, but I really wanted to
  avoid a rebase of the urgent ones."

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  Revert "clocksource: Load the ACPI PM clocksource asynchronously"
  clockevents: tTack broadcast device mode change in tick_broadcast_switch_to_oneshot()
  itimer: Use printk_once instead of WARN_ONCE
  nohz: Fix stale jiffies update in tick_nohz_restart()
  tick: Document TICK_ONESHOT config option
  proc: stats: Use arch_idle_time for idle and iowait times if available
  itimer: Schedule silent NULL pointer fixup in setitimer() for removal
2012-04-12 15:16:26 -07:00
Linus Torvalds
4a1d7544fe Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Thomas Gleixner.

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86: Use correct byte-sized register constraint in __add()
  x86: Use correct byte-sized register constraint in __xchg_op()
  x86: vsyscall: Use NULL instead 0 for a pointer argument
2012-04-12 15:06:07 -07:00
Jesper Juhl
474a89885f staging: android: fix mem leaks in __persistent_ram_init()
If, in __persistent_ram_init(), the call to
persistent_ram_buffer_init() fails or the call to
persistent_ram_init_ecc() fails then we fail to free the memory we
allocated to 'prz' with kzalloc() - thus leaking it.

To prevent the leaks I consolidated all error exits from the function
at a 'err:' label at the end and made all error cases jump to that
label where we can then make sure we always free 'prz'. This is safe
since all the situations where the code bails out happen before 'prz'
has been stored anywhere and although we'll do a redundant kfree(NULL)
call in the case of kzalloc() itself failing that's OK since kfree()
deals gracefully with NULL pointers and I felt it was more important
to keep all error exits at a single location than to avoid that one
harmless/redundant kfree() on a error path.

Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Acked-by: Colin Cross <ccross@android.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-12 14:34:32 -07:00
Jesper Juhl
17b7e1ba1e staging: vt6656: Don't leak memory in drivers/staging/vt6656/ioctl.c::private_ioctl()
If copy_to_user() fails in the WLAN_CMD_GET_NODE_LIST case of the
switch in drivers/staging/vt6656/ioctl.c::private_ioctl() we'll leak
the memory allocated to 'pNodeList'. Fix that by kfree'ing the memory
in the failure case.
Also remove a pointless cast (to type 'PSNodeList') of a kmalloc()
return value - kmalloc() returns a void pointer that is implicitly
converted, so there is no need for an explicit cast.

Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-12 14:34:31 -07:00
Marek Belisko
62d2feb980 staging: iio: hmc5843: Fix crash in probe function.
Fix crash after issuing:
	echo hmc5843 0x1e > /sys/class/i2c-dev/i2c-2/device/new_device

	[   37.180999] device: '2-001e': device_add
	[   37.188293] bus: 'i2c': add device 2-001e
	[   37.194549] PM: Adding info for i2c:2-001e
	[   37.200958] bus: 'i2c': driver_probe_device: matched device 2-001e with driver hmc5843
	[   37.210815] bus: 'i2c': really_probe: probing driver hmc5843 with device 2-001e
	[   37.224884] HMC5843 initialized
	[   37.228759] ------------[ cut here ]------------
	[   37.233612] kernel BUG at mm/slab.c:505!
	[   37.237701] Internal error: Oops - BUG: 0 [#1] PREEMPT
	[   37.243103] Modules linked in:
	[   37.246337] CPU: 0    Not tainted  (3.3.1-gta04+ #28)
	[   37.251647] PC is at kfree+0x84/0x144
	[   37.255493] LR is at kfree+0x20/0x144
	[   37.259338] pc : [<c00b408c>]    lr : [<c00b4028>]    psr: 40000093
	[   37.259368] sp : de249cd8  ip : 0000000c  fp : 00000090
	[   37.271362] r10: 0000000a  r9 : de229eac  r8 : c0236274
	[   37.276855] r7 : c09d6490  r6 : a0000013  r5 : de229c00  r4 : de229c10
	[   37.283691] r3 : c0f00218  r2 : 00000400  r1 : c0eea000  r0 : c00b4028
	[   37.290527] Flags: nZcv  IRQs off  FIQs on  Mode SVC_32  ISA ARM  Segment user
	[   37.298095] Control: 10c5387d  Table: 9e1d0019  DAC: 00000015
	[   37.304107] Process sh (pid: 91, stack limit = 0xde2482f0)
	[   37.309844] Stack: (0xde249cd8 to 0xde24a000)
	[   37.314422] 9cc0:                                                       de229c10 de229c00
	[   37.322998] 9ce0: de229c10 ffffffea 00000005 c0236274 de140a80 c00b4798 dec00080 de140a80
	[   37.331573] 9d00: c032f37c dec00080 000080d0 00000001 de229c00 de229c10 c048d578 00000005
	[   37.340148] 9d20: de229eac 0000000a 00000090 c032fa40 00000001 00000000 00000001 de229c10
	[   37.348724] 9d40: de229eac 00000029 c075b558 00000001 00000003 00000004 de229c10 c048d594
	[   37.357299] 9d60: 00000000 60000013 00000018 205b0007 37332020 3432322e 5d343838 c0060020
	[   37.365905] 9d80: de251600 00000001 00000000 de251600 00000001 c0065a84 de229c00 de229c48
	[   37.374481] 9da0: 00000006 0048d62c de229c38 de229c00 de229c00 de1f6c00 de1f6c20 00000001
	[   37.383056] 9dc0: 00000000 c048d62c 00000000 de229c00 de229c00 de1f6c00 de1f6c20 00000001
	[   37.391632] 9de0: 00000000 c048d62c 00000000 c0330164 00000000 de1f6c20 c048d62c de1f6c00
	[   37.400207] 9e00: c0330078 de1f6c04 c078d714 de189b58 00000000 c02ccfd8 de1f6c20 c0795f40
	[   37.408782] 9e20: c0238330 00000000 00000000 c02381a8 de1b9fc0 de1f6c20 de1f6c20 de249e48
	[   37.417358] 9e40: c0238330 c0236bb0 decdbed8 de7d0f14 de1f6c20 de1f6c20 de1f6c54 de1f6c20
	[   37.425933] 9e60: 00000000 c0238030 de1f6c20 c078d7bc de1f6c20 c02377ec de1f6c20 de1f6c28
	[   37.434509] 9e80: dee64cb0 c0236138 c047c554 de189b58 00000000 c004b45c de1f6c20 de1f6cd8
	[   37.443084] 9ea0: c0edfa6c de1f6c00 dee64c68 de1f6c04 de1f6c20 dee64cb8 c047c554 de189b58
	[   37.451690] 9ec0: 00000000 c02cd634 dee64c68 de249ef4 de23b008 dee64cb0 0000000d de23b000
	[   37.460266] 9ee0: de23b007 c02cd78c 00000002 00000000 00000000 35636d68 00333438 00000000
	[   37.468841] 9f00: 00000000 00000000 001e0000 00000000 00000000 00000000 00000000 0a10cec0
	[   37.477416] 9f20: 00000002 de249f80 0000000d dee62990 de189b40 c0234d88 0000000d c010c354
	[   37.485992] 9f40: 0000000d de210f28 000acc88 de249f80 0000000d de248000 00000000 c00b7bf8
	[   37.494567] 9f60: de210f28 000acc88 de210f28 000acc88 00000000 00000000 0000000d c00b7ed8
	[   37.503143] 9f80: 00000000 00000000 0000000d 00000000 0007fa28 0000000d 000acc88 00000004
	[   37.511718] 9fa0: c000e544 c000e380 0007fa28 0000000d 00000001 000acc88 0000000d 00000000
	[   37.520294] 9fc0: 0007fa28 0000000d 000acc88 00000004 00000001 00000020 00000002 00000000
	[   37.528869] 9fe0: 00000000 beab8624 0000ea05 b6eaebac 600d0010 00000001 00000000 00000000
	[   37.537475] [<c00b408c>] (kfree+0x84/0x144) from [<c0236274>] (device_add+0x530/0x57c)
	[   37.545806] [<c0236274>] (device_add+0x530/0x57c) from [<c032fa40>] (iio_device_register+0x8c8/0x990)
	[   37.555480] [<c032fa40>] (iio_device_register+0x8c8/0x990) from [<c0330164>] (hmc5843_probe+0xec/0x114)
	[   37.565338] [<c0330164>] (hmc5843_probe+0xec/0x114) from [<c02ccfd8>] (i2c_device_probe+0xc4/0xf8)
	[   37.574737] [<c02ccfd8>] (i2c_device_probe+0xc4/0xf8) from [<c02381a8>] (driver_probe_device+0x118/0x218)
	[   37.584777] [<c02381a8>] (driver_probe_device+0x118/0x218) from [<c0236bb0>] (bus_for_each_drv+0x4c/0x84)
	[   37.594818] [<c0236bb0>] (bus_for_each_drv+0x4c/0x84) from [<c0238030>] (device_attach+0x78/0xa4)
	[   37.604125] [<c0238030>] (device_attach+0x78/0xa4) from [<c02377ec>] (bus_probe_device+0x28/0x9c)
	[   37.613433] [<c02377ec>] (bus_probe_device+0x28/0x9c) from [<c0236138>] (device_add+0x3f4/0x57c)
	[   37.622650] [<c0236138>] (device_add+0x3f4/0x57c) from [<c02cd634>] (i2c_new_device+0xf8/0x19c)
	[   37.631805] [<c02cd634>] (i2c_new_device+0xf8/0x19c) from [<c02cd78c>] (i2c_sysfs_new_device+0xb4/0x130)
	[   37.641754] [<c02cd78c>] (i2c_sysfs_new_device+0xb4/0x130) from [<c0234d88>] (dev_attr_store+0x18/0x24)
	[   37.651611] [<c0234d88>] (dev_attr_store+0x18/0x24) from [<c010c354>] (sysfs_write_file+0x10c/0x140)
	[   37.661193] [<c010c354>] (sysfs_write_file+0x10c/0x140) from [<c00b7bf8>] (vfs_write+0xb0/0x178)
	[   37.670410] [<c00b7bf8>] (vfs_write+0xb0/0x178) from [<c00b7ed8>] (sys_write+0x3c/0x68)
	[   37.678833] [<c00b7ed8>] (sys_write+0x3c/0x68) from [<c000e380>] (ret_fast_syscall+0x0/0x3c)
	[   37.687683] Code: 1593301c e5932000 e3120080 1a000000 (e7f001f2)
	[   37.700775] ---[ end trace aaf805debdb69390 ]---

Client data was assigned to iio_dev structure in probe but in
hmc5843_init_client function casted to private driver data structure which
is wrong. Possibly calling mutex_init(&data->lock); corrupt data
which the lead to above crash.

Signed-off-by: Marek Belisko <marek.belisko@open-nandra.com>
Cc: stable <stable@vger.kernel.org>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-12 14:34:31 -07:00
Linus Torvalds
ecca5c3acc Merge branch 'akpm' (Andrew's patch-bomb)
Merge fixes from Andrew Morton.

* emailed from Andrew Morton <akpm@linux-foundation.org>: (14 patches)
  panic: fix stack dump print on direct call to panic()
  drivers/rtc/rtc-pl031.c: enable clock on all ST variants
  Revert "mm: vmscan: fix misused nr_reclaimed in shrink_mem_cgroup_zone()"
  hugetlb: fix race condition in hugetlb_fault()
  drivers/rtc/rtc-twl.c: use static register while reading time
  drivers/rtc/rtc-s3c.c: add placeholder for driver private data
  drivers/rtc/rtc-s3c.c: fix compilation error
  MAINTAINERS: add PCDP console maintainer
  memcg: do not open code accesses to res_counter members
  drivers/rtc/rtc-efi.c: fix section mismatch warning
  drivers/rtc/rtc-r9701.c: reset registers if invalid values are detected
  drivers/char/random.c: fix boot id uniqueness race
  memcg: fix broken boolen expression
  memcg: fix up documentation on global LRU
2012-04-12 14:15:21 -07:00
Linus Torvalds
174808af90 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Fix bluetooth userland regression reported by Keith Packard, from
    Gustavo Padovan.

 2) Revert ath9k PS idle change, from Sujith Manoharan.

 3) Correct default TCP memory limits (again), from Eric Dumazet.

 4) Fix tcp_rcv_rtt_update() accidental use of unscaled RTT, from Neal
    Cardwell.

 5) We made a facility for layers like wireless to say how much tailroom
    they need in the SKB for link layer stuff such as wireless
    encryption etc., but TCP works hard to fill every SKB out to the end
    defeating this specification.

    This leads to every TCP packet getting reallocated by the wireless
    code in order to have the right amount of tailroom available.

    Fix TCP to only fill SKBs out to the real amount of data area it
    asked for during the allocation, this way it won't eat into the
    slack added for the device's tailroom needs.

    Reported by Marc Merlin and fixed by Eric Dumazet.

 6) Leaks, endian bugs, and new device IDs in bluetooth from Santosh
    Nayak, João Paulo Rechi Vita, Cho, Yu-Chen, Andrei Emeltchenko,
    AceLan Kao, and Andrei Emeltchenko.

 7) OOPS on tty_close fix in bluetooth's hci_ldisc from Johan Hovold.

 8) netfilter erroneously scales TCP window twice, fix from Changli Gao.

 9) Memleak fix in wext-core from Julia Lawall.

10) Consistently handle invalid TCP packets in ipv4 vs.  ipv6 conntrack,
    from Jozsef Kadlecsik.

11) Validate IP header length properly in netfilter conntrack's
    ipv4_get_l4proto().

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (39 commits)
  NFC: Fix the LLCP Tx fragmentation loop
  rtlwifi: Add missing DMA buffer unmapping for PCI drivers
  rtlwifi: Preallocate USB read buffers and eliminate kalloc in read routine
  tcp: avoid order-1 allocations on wifi and tx path
  net: allow pskb_expand_head() to get maximum tailroom
  bridge: Do not send queries on multicast group leaves
  MAINTAINERS: Mark NATSEMI driver as orphan'd.
  tcp: fix tcp_rcv_rtt_update() use of an unscaled RTT sample
  tcp: restore correct limit
  Revert "ath9k: fix going to full-sleep on PS idle"
  rt2x00: Fix rfkill_polling register function.
  bcma: fix build error on MIPS; implicit pcibios_enable_device
  netfilter: nf_conntrack: fix incorrect logic in nf_conntrack_init_net
  netfilter: nf_ct_ipv4: packets with wrong ihl are invalid
  netfilter: nf_ct_ipv4: handle invalid IPv4 and IPv6 packets consistently
  net/wireless/wext-core.c: add missing kfree
  rtlwifi: Fix oops on rate-control failure
  mac80211: Convert WARN_ON to WARN_ON_ONCE
  rtlwifi: rtl8192de: Fix firmware initialization
  nl80211: ensure interface is up in various APIs
  ...
2012-04-12 14:04:33 -07:00
Linus Torvalds
778c2dee6f Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linux
Pull drm fixes from Dave Airlie:
 "Mostly exynos and intel.

  Intel has 3 regression fixers (more info in intel merge commit), along
  with some other make hw work fixes, exynos has some cleanups and an
  ioctl fix.

  A couple of radeon fixes, couple of build fixes, and a savage
  userspace interface possible overflow fix."

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux: (23 commits)
  drm/exynos: fixed exynos broken ioctl
  drm/i915: clear fencing tracking state when retiring requests
  drm/exynos: fix to pointer manager member of struct exynos_drm_subdrv
  drm/exynos: fix struct for operation callback functions to driver name
  drm/exynos: use define instead of default_win member in struct mixer_context
  drm/exynos: rename s/HDMI_OVERLAY_NUMBER/MIXER_WIN_NR
  drm/exynos: remove unused codes in hdmi and mixer
  drm/exynos: remove unnecessary type conversion of hdmi and mixer
  drm/i915: make rc6 module parameter read-only
  drm/i915: implement ColorBlt w/a
  drm/i915/ringbuffer: Exclude last 2 cachlines of ring on 845g
  Revert "drm/i915: reenable gmbus on gen3+ again"
  drm/radeon: only add the mm i2c bus if the hw_i2c module param is set
  vgaarb.h: fix build warnings
  drm/i915: properly compute dp dithering for user-created modes
  drm/radeon/kms: fix DVO setup on some r4xx chips
  drm/savage: fix integer overflows in savage_bci_cmdbuf()
  drm/radeon: replace udelay with mdelay for long timeouts
  drm/i915: Finish any pending operations on the framebuffer before disabling
  drm/i915: Removed IVB forced enable of sprite dest key.
  ...
2012-04-12 13:58:23 -07:00
Linus Torvalds
e42bd6e4a6 A few more fixes for md in 3.4
Two are tagged for -stable. They can cause an oops, but very rarely.
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Merge tag 'md-3.4-fixes' of git://neil.brown.name/md

Pull a few more fixes for md from NeilBrown:
 "Two are tagged for -stable.  They can cause an oops, but very rarely."

* tag 'md-3.4-fixes' of git://neil.brown.name/md:
  md/bitmap: prevent bitmap_daemon_work running while initialising bitmap
  md/raid1,raid10: Fix calculation of 'vcnt' when processing error recovery.
  MD: Bitmap version cleanup.
2012-04-12 13:12:56 -07:00
Jason Wessel
026ee1f66a panic: fix stack dump print on direct call to panic()
Commit 6e6f0a1f0f ("panic: don't print redundant backtraces on oops")
causes a regression where no stack trace will be printed at all for the
case where kernel code calls panic() directly while not processing an
oops, and of course there are 100's of instances of this type of call.

The original commit executed the check (!oops_in_progress), but this will
always be false because just before the dump_stack() there is a call to
bust_spinlocks(1), which does the following:

  void __attribute__((weak)) bust_spinlocks(int yes)
  {
	if (yes) {
		++oops_in_progress;

The proper way to resolve the problem that original commit tried to
solve is to avoid printing a stack dump from panic() when the either of
the following conditions is true:

  1) TAINT_DIE has been set (this is done by oops_end())
     This indicates and oops has already been printed.
  2) oops_in_progress > 1
     This guards against the rare case where panic() is invoked
     a second time, or in between oops_begin() and oops_end()

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: <stable@vger.kernel.org>	[3.3+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-04-12 13:12:12 -07:00
Linus Walleij
2f39721683 drivers/rtc/rtc-pl031.c: enable clock on all ST variants
The ST variants of the PL031 all require bit 26 in the control register
to be set before they work properly.  Discovered this when testing on
the Nomadik board where it would suprisingly just stand still.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Mian Yousaf Kaukab <mian.yousaf.kaukab@stericsson.com>
Cc: Alessandro Rubini <rubini@unipv.it>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-04-12 13:12:12 -07:00
Ying Han
41c9308812 Revert "mm: vmscan: fix misused nr_reclaimed in shrink_mem_cgroup_zone()"
This reverts commit c38446cc65.

Before the commit, the code makes senses to me but not after the commit.
The "nr_reclaimed" is the number of pages reclaimed by scanning through
the memcg's lru lists.  The "nr_to_reclaim" is the target value for the
whole function.  For example, we like to early break the reclaim if
reclaimed 32 pages under direct reclaim (not DEF_PRIORITY).

After the reverted commit, the target "nr_to_reclaim" is decremented each
time by "nr_reclaimed" but we still use it to compare the "nr_reclaimed".
It just doesn't make sense to me...

Signed-off-by: Ying Han <yinghan@google.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Hillf Danton <dhillf@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-04-12 13:12:12 -07:00
Chris Metcalf
66aebce747 hugetlb: fix race condition in hugetlb_fault()
The race is as follows:

Suppose a multi-threaded task forks a new process (on cpu A), thus
bumping up the ref count on all the pages.  While the fork is occurring
(and thus we have marked all the PTEs as read-only), another thread in
the original process (on cpu B) tries to write to a huge page, taking an
access violation from the write-protect and calling hugetlb_cow().  Now,
suppose the fork() fails.  It will undo the COW and decrement the ref
count on the pages, so the ref count on the huge page drops back to 1.
Meanwhile hugetlb_cow() also decrements the ref count by one on the
original page, since the original address space doesn't need it any
more, having copied a new page to replace the original page.  This
leaves the ref count at zero, and when we call unlock_page(), we panic.

	fork on CPU A				fault on CPU B
	=============				==============
	...
	down_write(&parent->mmap_sem);
	down_write_nested(&child->mmap_sem);
	...
	while duplicating vmas
		if error
			break;
	...
	up_write(&child->mmap_sem);
	up_write(&parent->mmap_sem);		...
						down_read(&parent->mmap_sem);
						...
						lock_page(page);
						handle COW
						page_mapcount(old_page) == 2
						alloc and prepare new_page
	...
	handle error
	page_remove_rmap(page);
	put_page(page);
	...
						fold new_page into pte
						page_remove_rmap(page);
						put_page(page);
						...
				oops ==>	unlock_page(page);
						up_read(&parent->mmap_sem);

The solution is to take an extra reference to the page while we are
holding the lock on it.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-04-12 13:12:12 -07:00
Konstantin Shlyakhovoy
f3ec434c69 drivers/rtc/rtc-twl.c: use static register while reading time
RTC stores time and date in several registers.  Due to the fact that
these registers can't be read instantaneously, there is a chance that
reading from counting registers gives an error of one minute, one hour,
one day, etc.

To address this issue, the RTC has hardware support to copy the RTC
counting registers to static shadowed registers.  The current
implementation does not use this feature, and in a stress test, we can
reproduce this error at a rate of around two times per 300000 readings.

Fix the implementation to ensure that the right snapshot of time is
captured.

Signed-off-by: Konstantin Shlyakhovoy <x0155534@ti.com>
Signed-off-by: Nishanth Menon <nm@ti.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Benoit Cousson <b-cousson@ti.com>
Cc: linux-omap <linux-omap@vger.kernel.org>
Acked-by: Mykola Oleksiienko <x0174904@ti.com>
Acked-by: Oleksandr Dmytryshyn <oleksandr.dmytryshyn@ti.com>
Acked-by: Graeme Gregory <gg@slimlogic.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-04-12 13:12:12 -07:00