The page_table_free_pgste function is used for kvm processes to free page
tables that have the pgste extension. It calls pgtable_page_ctor instead of
pgtable_page_dtor which increases NR_PAGETABLE instead of decreasing it.
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Avoid calling wake_up() from our NMI "bottom halve" from RCU extended
quiescent state in idle. wake_up() has RCU read-side critical sections
but this will be completely ignored by RCU if the cpu is in extended
quiescent state.
Which means that whatever object is being accessed from within the
read-side critical section can be freed concurrently from a different
cpu.
So make sure we leave extended quiescent state before calling wake_up().
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

The AMD K7/K8 CPUs don't save/restore FDP/FIP/FOP unless an exception is
pending.  In order to not leak FIP state from one process to another, we
need to do a floating point load after the fxsave of the old process,
and before the fxrstor of the new FPU state.  That resets the state to
the (uninteresting) kernel load, rather than some potentially sensitive
user information.

We used to do this directly after the FPU state save, but that is
actually very inconvenient, since it

 (a) corrupts what is potentially perfectly good FPU state that we might
     want to lazy avoid restoring later and

 (b) on x86-64 it resulted in a very annoying ordering constraint, where
     "__unlazy_fpu()" in the task switch needs to be delayed until after
     the DS segment has been reloaded just to get the new DS value.

Coupling it to the fxrstor instead of the fxsave automatically avoids
both of these issues, and also ensures that we only do it when actually
necessary (the FP state after a save may never actually get used).  It's
simply a much more natural place for the leaked state cleanup.
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Yes, taking the trap to re-load the FPU/MMX state is expensive, but so
is spending several days looking for a bug in the state save/restore
code.  And the preload code has some rather subtle interactions with
both paravirtualization support and segment state restore, so it's not
nearly as simple as it should be.

Also, now that we no longer necessarily depend on a single bit (ie
TS_USEDFPU) for keeping track of the state of the FPU, we migth be able
to do better.  If we are really switching between two processes that
keep touching the FP state, save/restore is inevitable, but in the case
of having one process that does most of the FPU usage, we may actually
be able to do much better than the preloading.

In particular, we may be able to keep track of which CPU the process ran
on last, and also per CPU keep track of which process' FP state that CPU
has.  For modern CPU's that don't destroy the FPU contents on save time,
that would allow us to do a lazy restore by just re-enabling the
existing FPU state - with no restore cost at all!
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This creates three helper functions that do the TS_USEDFPU accesses, and
makes everybody that used to do it by hand use those helpers instead.

In addition, there's a couple of helper functions for the "change both
CR0.TS and TS_USEDFPU at the same time" case, and the places that do
that together have been changed to use those.  That means that we have
fewer random places that open-code this situation.

The intent is partly to clarify the code without actually changing any
semantics yet (since we clearly still have some hard to reproduce bug in
this area), but also to make it much easier to use another approach
entirely to caching the CR0.TS bit for software accesses.

Right now we use a bit in the thread-info 'status' variable (this patch
does not change that), but we might want to make it a full field of its
own or even make it a per-cpu variable.
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Touching TS_USEDFPU without touching CR0.TS is confusing, so don't do
it.  By moving it into the callers, we always do the TS_USEDFPU next to
the CR0.TS accesses in the source code, and it's much easier to see how
the two go hand in hand.
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit 5b1cbac3 ("i387: make irq_fpu_usable() tests more robust")
added a sanity check to the #NM handler to verify that we never cause
the "Device Not Available" exception in kernel mode.

However, that check actually pinpointed a (fundamental) race where we do
cause that exception as part of the signal stack FPU state save/restore
code.

Because we use the floating point instructions themselves to save and
restore state directly from user mode, we cannot do that atomically with
testing the TS_USEDFPU bit: the user mode access itself may cause a page
fault, which causes a task switch, which saves and restores the FP/MMX
state from the kernel buffers.

This kind of "recursive" FP state save is fine per se, but it means that
when the signal stack save/restore gets restarted, it will now take the
'#NM' exception we originally tried to avoid.  With preemption this can
happen even without the page fault - but because of the user access, we
cannot just disable preemption around the save/restore instruction.

There are various ways to solve this, including using the
"enable/disable_page_fault()" helpers to not allow page faults at all
during the sequence, and fall back to copying things by hand without the
use of the native FP state save/restore instructions.

However, the simplest thing to do is to just allow the #NM from kernel
space, but fix the race in setting and clearing CR0.TS that this all
exposed: the TS bit changes and the TS_USEDFPU bit absolutely have to be
atomic wrt scheduling, so while the actual state save/restore can be
interrupted and restarted, the act of actually clearing/setting CR0.TS
and the TS_USEDFPU bit together must not.

Instead of just adding random "preempt_disable/enable()" calls to what
is already excessively ugly code, this introduces some helper functions
that mostly mirror the "kernel_fpu_begin/end()" functionality, just for
the user state instead.

Those helper functions should probably eventually replace the other
ad-hoc CR0.TS and TS_USEDFPU tests too, but I'll need to think about it
some more: the task switching functionality in particular needs to
expose the difference between the 'prev' and 'next' threads, while the
new helper functions intentionally were written to only work with
'current'.
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The check for save_init_fpu() (introduced in commit 5b1cbac3: "i387:
make irq_fpu_usable() tests more robust") was the wrong way around, but
I hadn't noticed, because my "tests" were bogus: the FPU exceptions are
disabled by default, so even doing a divide by zero never actually
triggers this code at all unless you do extra work to enable them.

So if anybody did enable them, they'd get one spurious warning.
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

EEH may happen during a PCI driver probe. If the driver is trying to
access some register in a loop, the EEH code will try to print the
driver name. But the driver pointer in struct pci_dev is not set until
probe returns successfully.

Use a function to test if the device and the driver pointer is NULL
before accessing the driver's name.
Signed-off-by: NThadeu Lima de Souza Cascardo <cascardo@linux.vnet.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

This fixes a hang that was observed during live partition migration.
Since stop_topology_update must not be called from an interrupt
context, call it earlier in the migration process. The hang observed
can be seen below:

WARNING: at kernel/timer.c:1011
Modules linked in: ip6t_LOG xt_tcpudp xt_pkttype ipt_LOG xt_limit ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 ip6table_raw xt_NOTRACK ipt_REJECT xt_state iptable_raw iptable_filter ip6table_mangle nf_conntrack_netbios_ns nf_conntrack_broadcast nf_conntrack_ipv4 nf_conntrack nf_defrag_ipv4 ip_tables ip6table_filter ip6_tables x_tables ipv6 fuse loop ibmveth sg ext3 jbd mbcache raid456 async_raid6_recov async_pq raid6_pq async_xor xor async_memcpy async_tx raid10 raid1 raid0 scsi_dh_alua scsi_dh_rdac scsi_dh_hp_sw scsi_dh_emc dm_round_robin dm_multipath scsi_dh sd_mod crc_t10dif ibmvfc scsi_transport_fc scsi_tgt scsi_mod dm_snapshot dm_mod
NIP: c0000000000c52d8 LR: c00000000004be28 CTR: 0000000000000000
REGS: c00000005ffd77d0 TRAP: 0700   Not tainted  (3.2.0-git-00001-g07d106d0)
MSR: 8000000000021032 <ME,CE,IR,DR>  CR: 48000084  XER: 00000001
CFAR: c00000000004be20
TASK = c00000005ec78860[0] 'swapper/3' THREAD: c00000005ec98000 CPU: 3
GPR00: 0000000000000001 c00000005ffd7a50 c000000000fbbc98 c000000000ec8340
GPR04: 00000000282a0020 0000000000000000 0000000000004000 0000000000000101
GPR08: 0000000000000012 c00000005ffd4000 0000000000000020 c000000000f3ba88
GPR12: 0000000000000000 c000000007f40900 0000000000000001 0000000000000004
GPR16: 0000000000000001 0000000000000000 0000000000000000 c000000001022310
GPR20: 0000000000000001 0000000000000000 0000000000200200 c000000001029e14
GPR24: 0000000000000000 0000000000000001 0000000000000040 c00000003f74bc80
GPR28: c00000003f74bc84 c000000000f38038 c000000000f16b58 c000000000ec8340
NIP [c0000000000c52d8] .del_timer_sync+0x28/0x60
LR [c00000000004be28] .stop_topology_update+0x20/0x38
Call Trace:
[c00000005ffd7a50] [c00000005ec78860] 0xc00000005ec78860 (unreliable)
[c00000005ffd7ad0] [c00000000004be28] .stop_topology_update+0x20/0x38
[c00000005ffd7b40] [c000000000028378] .__rtas_suspend_last_cpu+0x58/0x260
[c00000005ffd7bf0] [c0000000000fa230] .generic_smp_call_function_interrupt+0x160/0x358
[c00000005ffd7cf0] [c000000000036ec8] .smp_ipi_demux+0x88/0x100
[c00000005ffd7d80] [c00000000005c154] .icp_hv_ipi_action+0x5c/0x80
[c00000005ffd7e00] [c00000000012a088] .handle_irq_event_percpu+0x100/0x318
[c00000005ffd7f00] [c00000000012e774] .handle_percpu_irq+0x84/0xd0
[c00000005ffd7f90] [c000000000022ba8] .call_handle_irq+0x1c/0x2c
[c00000005ec9ba20] [c00000000001157c] .do_IRQ+0x22c/0x2a8
[c00000005ec9bae0] [c0000000000054bc] hardware_interrupt_entry+0x18/0x1c
Exception: 501 at .cpu_idle+0x194/0x2f8
    LR = .cpu_idle+0x194/0x2f8
[c00000005ec9bdd0] [c000000000017e58] .cpu_idle+0x188/0x2f8 (unreliable)
[c00000005ec9be90] [c00000000067ec18] .start_secondary+0x3e4/0x524
[c00000005ec9bf90] [c0000000000093e8] .start_secondary_prolog+0x10/0x14
Instruction dump:
ebe1fff8 4e800020 fbe1fff8 7c0802a6 f8010010 7c7f1b78 f821ff81 78290464
80090014 5400019e 7c0000d0 78000fe0 <0b000000> 4800000c 7c210b78 7c421378
Signed-off-by: NBrian King <brking@linux.vnet.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

We need to disable interrupts when taking the phb->lock. Otherwise
we could deadlock with pci_lock taken from an interrupt.
Signed-off-by: NMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

We use __get_cpu_var() which triggers a false positive warning
in smp_processor_id() thinking interrupts are enabled (at this
point, they are soft-enabled but hard-disabled).
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

We call the cache_hwirq_map() function with a linux IRQ number
but it expects a HW irq number. This triggers a BUG on multic-chip
setups in addition to not doing the right thing.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

With this change, helpers such as instruction_pointer() et al, get defined
in the generic header in terms of GET_IP

Removed the unnecessary definition of profile_pc in !CONFIG_SMP case as
suggested by Mike Frysinger.
Signed-off-by: NSrikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: NAnanth N Mavinakayanahalli <ananth@in.ibm.com>
Acked-by: NMike Frysinger <vapier@gentoo.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

It appears that on the Chroma card, the class code of the root
complex is still wrong even on DD2 or later chips. This could
be a firmware issue, but that breaks resource allocation so let's
unconditionally fix it up.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Some code - especially the crypto layer - wants to use the x86
FP/MMX/AVX register set in what may be interrupt (typically softirq)
context.

That *can* be ok, but the tests for when it was ok were somewhat
suspect.  We cannot touch the thread-specific status bits either, so
we'd better check that we're not going to try to save FP state or
anything like that.

Now, it may be that the TS bit is always cleared *before* we set the
USEDFPU bit (and only set when we had already cleared the USEDFP
before), so the TS bit test may actually have been sufficient, but it
certainly was not obviously so.

So this explicitly verifies that we will not touch the TS_USEDFPU bit,
and adds a few related sanity-checks.  Because it seems that somehow
AES-NI is corrupting user FP state.  The cause is not clear, and this
patch doesn't fix it, but while debugging it I really wanted the code to
be more obviously correct and robust.
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

It was marked asmlinkage for some really old and stale legacy reasons.
Fix that and the equally stale comment.

Noticed when debugging the irq_fpu_usable() bugs.
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

It's useful to print the error code when a called function fails so a
diagnosis of why it failed is possible.  In this case, it fails because
we try to register some data for the wl12xx driver, but as the driver
is not configured, a stub function is used which simply returns -ENOSYS.

Let's do the simple thing for -rc and print the error code.

Also, the return code from platform_register_device() at each of these
sites was not being checked.  Add some checking, and again print the
error code.

This should be fixed properly for the next merge window so we don't
issue error messages merely because a driver is not configured.
Acked-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

While trying to debug my OMAP platforms, they emitted this message:

omap_hwmod: %s: enabled state can only be entered from initialized, idle, or disabled state

The following backtrace said it was from a function called '_enable',
which didn't provide much clue.  Grepping didn't find it either.

The message is wrapped, so unwrap the message so grep can find it.  Do
the same for three other messages in this file.
Acked-by: NPaul Walmsley <paul@pwsan.com>
Acked-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The previous commit causes new section mismatch warnings:

WARNING: arch/arm/mach-omap2/built-in.o(.text+0xdb30): Section mismatch in reference from the function omap_init_hsmmc() to the function .init.text:omap_mux_init_gpio()
The function omap_init_hsmmc() references
the function __init omap_mux_init_gpio().
This is often because omap_init_hsmmc lacks a __init
annotation or the annotation of omap_mux_init_gpio is wrong.

WARNING: arch/arm/mach-omap2/built-in.o(.text+0xdb4c): Section mismatch in reference from the function omap_init_hsmmc() to the function .init.text:omap_mux_init_gpio()
The function omap_init_hsmmc() references
the function __init omap_mux_init_gpio().
This is often because omap_init_hsmmc lacks a __init
annotation or the annotation of omap_mux_init_gpio is wrong.

WARNING: arch/arm/mach-omap2/built-in.o(.text+0xdb60): Section mismatch in reference from the function omap_init_hsmmc() to the function .init.text:omap_mux_init_signal()
The function omap_init_hsmmc() references
the function __init omap_mux_init_signal().
This is often because omap_init_hsmmc lacks a __init
annotation or the annotation of omap_mux_init_signal is wrong.

WARNING: arch/arm/mach-omap2/built-in.o(.text+0xdb6c): Section mismatch in reference from the function omap_init_hsmmc() to the function .init.text:omap_mux_init_signal()
The function omap_init_hsmmc() references
the function __init omap_mux_init_signal().
This is often because omap_init_hsmmc lacks a __init
annotation or the annotation of omap_mux_init_signal is wrong.

WARNING: arch/arm/mach-omap2/built-in.o(.text+0xdb78): Section mismatch in reference from the function omap_init_hsmmc() to the function .init.text:omap_mux_init_signal()
The function omap_init_hsmmc() references
the function __init omap_mux_init_signal().
This is often because omap_init_hsmmc lacks a __init
annotation or the annotation of omap_mux_init_signal is wrong.

WARNING: arch/arm/mach-omap2/built-in.o(.text+0xdb90): Section mismatch in reference from the function omap_init_hsmmc() to the function .init.text:omap_mux_init_signal()
The function omap_init_hsmmc() references
the function __init omap_mux_init_signal().
This is often because omap_init_hsmmc lacks a __init
annotation or the annotation of omap_mux_init_signal is wrong.

WARNING: arch/arm/mach-omap2/built-in.o(.text+0xdb9c): Section mismatch in reference from the function omap_init_hsmmc() to the function .init.text:omap_mux_init_signal()
The function omap_init_hsmmc() references
the function __init omap_mux_init_signal().
This is often because omap_init_hsmmc lacks a __init
annotation or the annotation of omap_mux_init_signal is wrong.

WARNING: arch/arm/mach-omap2/built-in.o(.text+0xdba8): Section mismatch in reference from the function omap_init_hsmmc() to the function .init.text:omap_mux_init_signal()
The function omap_init_hsmmc() references
the function __init omap_mux_init_signal().
This is often because omap_init_hsmmc lacks a __init
annotation or the annotation of omap_mux_init_signal is wrong.

WARNING: arch/arm/mach-omap2/built-in.o(.text+0xdbc0): Section mismatch in reference from the function omap_init_hsmmc() to the function .init.text:omap_mux_init_signal()
The function omap_init_hsmmc() references
the function __init omap_mux_init_signal().
This is often because omap_init_hsmmc lacks a __init
annotation or the annotation of omap_mux_init_signal is wrong.

WARNING: arch/arm/mach-omap2/built-in.o(.text+0xdbcc): Section mismatch in reference from the function omap_init_hsmmc() to the function .init.text:omap_mux_init_signal()
The function omap_init_hsmmc() references
the function __init omap_mux_init_signal().
This is often because omap_init_hsmmc lacks a __init
annotation or the annotation of omap_mux_init_signal is wrong.

WARNING: arch/arm/mach-omap2/built-in.o(.text+0xdbd8): Section mismatch in reference from the function omap_init_hsmmc() to the function .init.text:omap_mux_init_signal()
The function omap_init_hsmmc() references
the function __init omap_mux_init_signal().
This is often because omap_init_hsmmc lacks a __init
annotation or the annotation of omap_mux_init_signal is wrong.

WARNING: arch/arm/mach-omap2/built-in.o(.text+0xdbf8): Section mismatch in reference from the function omap_init_hsmmc() to the function .init.text:omap_mux_init_signal()
The function omap_init_hsmmc() references
the function __init omap_mux_init_signal().
This is often because omap_init_hsmmc lacks a __init
annotation or the annotation of omap_mux_init_signal is wrong.

WARNING: arch/arm/mach-omap2/built-in.o(.text+0xdc04): Section mismatch in reference from the function omap_init_hsmmc() to the function .init.text:omap_mux_init_signal()
The function omap_init_hsmmc() references
the function __init omap_mux_init_signal().
This is often because omap_init_hsmmc lacks a __init
annotation or the annotation of omap_mux_init_signal is wrong.

WARNING: arch/arm/mach-omap2/built-in.o(.text+0xdc10): Section mismatch in reference from the function omap_init_hsmmc() to the function .init.text:omap_mux_init_signal()
The function omap_init_hsmmc() references
the function __init omap_mux_init_signal().
This is often because omap_init_hsmmc lacks a __init
annotation or the annotation of omap_mux_init_signal is wrong.

WARNING: arch/arm/mach-omap2/built-in.o(.text+0xdc28): Section mismatch in reference from the function omap_init_hsmmc() to the function .init.text:omap_mux_init_signal()
The function omap_init_hsmmc() references
the function __init omap_mux_init_signal().
This is often because omap_init_hsmmc lacks a __init
annotation or the annotation of omap_mux_init_signal is wrong.

WARNING: arch/arm/mach-omap2/built-in.o(.text+0xdc34): Section mismatch in reference from the function omap_init_hsmmc() to the function .init.text:omap_mux_init_signal()
The function omap_init_hsmmc() references
the function __init omap_mux_init_signal().
This is often because omap_init_hsmmc lacks a __init
annotation or the annotation of omap_mux_init_signal is wrong.

WARNING: arch/arm/mach-omap2/built-in.o(.text+0xdc40): Section mismatch in reference from the function omap_init_hsmmc() to the function .init.text:omap_mux_init_signal()
The function omap_init_hsmmc() references
the function __init omap_mux_init_signal().
This is often because omap_init_hsmmc lacks a __init
annotation or the annotation of omap_mux_init_signal is wrong.

WARNING: arch/arm/mach-omap2/built-in.o(.text+0xdc58): Section mismatch in reference from the function omap_init_hsmmc() to the function .init.text:omap_mux_init_signal()
The function omap_init_hsmmc() references
the function __init omap_mux_init_signal().
This is often because omap_init_hsmmc lacks a __init
annotation or the annotation of omap_mux_init_signal is wrong.

WARNING: arch/arm/mach-omap2/built-in.o(.text+0xdc64): Section mismatch in reference from the function omap_init_hsmmc() to the function .init.text:omap_mux_init_signal()
The function omap_init_hsmmc() references
the function __init omap_mux_init_signal().
This is often because omap_init_hsmmc lacks a __init
annotation or the annotation of omap_mux_init_signal is wrong.

WARNING: arch/arm/mach-omap2/built-in.o(.text+0xdc70): Section mismatch in reference from the function omap_init_hsmmc() to the function .init.text:omap_mux_init_signal()
The function omap_init_hsmmc() references
the function __init omap_mux_init_signal().
This is often because omap_init_hsmmc lacks a __init
annotation or the annotation of omap_mux_init_signal is wrong.

WARNING: arch/arm/mach-omap2/built-in.o(.text+0xdc7c): Section mismatch in reference from the function omap_init_hsmmc() to the function .init.text:omap_mux_init_signal()
The function omap_init_hsmmc() references
the function __init omap_mux_init_signal().
This is often because omap_init_hsmmc lacks a __init
annotation or the annotation of omap_mux_init_signal is wrong.

Again, as for omap2_hsmmc_init(), these functions are callable at
runtime via the gpio-twl4030.c driver, and so these can't be marked
__init.
Acked-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

WARNING: arch/arm/mach-omap2/built-in.o(.text+0xd0f0): Section mismatch in reference from the function sdp3430_twl_gpio_setup() to the function .init.text:omap2_hsmmc_init()
The function sdp3430_twl_gpio_setup() references
the function __init omap2_hsmmc_init().
This is often because sdp3430_twl_gpio_setup lacks a __init
annotation or the annotation of omap2_hsmmc_init is wrong.

sdp3430_twl_gpio_setup() is called via platform data from the
gpio-twl4030 module, which can be inserted and removed at runtime.
This makes sdp3430_twl_gpio_setup() callable at runtime, and prevents
it being marked with an __init annotation.

As it calls omap2_hsmmc_init() unconditionally, the only resolution to
this warning is to remove the __init markings from omap2_hsmmc_init()
and its called functions.  This addresses the functions in hsmmc.c.
Acked-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

WARNING: arch/arm/mach-omap2/built-in.o(.text+0xb798): Section mismatch in reference from the function omap_4430sdp_display_init() to the function .init.text:omap_display_init()
The function omap_4430sdp_display_init() references
the function __init omap_display_init().
This is often because omap_4430sdp_display_init lacks a __init
annotation or the annotation of omap_display_init is wrong.

Fix this by adding __init to omap_4430sdp_display_init().
Acked-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

WARNING: vmlinux.o(.text+0x1c664): Section mismatch in reference from the function omap_secondary_startup() to the function .cpuinit.text:secondary_startup()
The function omap_secondary_startup() references
the function __cpuinit secondary_startup().
This is often because omap_secondary_startup lacks a __cpuinit
annotation or the annotation of secondary_startup is wrong.

Unfortunately, fixing this causes a new warning which is harder to
solve:

WARNING: arch/arm/mach-omap2/built-in.o(.text+0x5328): Section mismatch in reference from the function omap4_hotplug_cpu() to the function .cpuinit.text:omap_secondary_startup()
The function omap4_hotplug_cpu() references
the function __cpuinit omap_secondary_startup().
This is often because omap4_hotplug_cpu lacks a __cpuinit
annotation or the annotation of omap_secondary_startup is wrong.

because omap4_hotplug_cpu() is used by power management code as well,
which may not end up using omap_secondary_startup().
Acked-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Found by review.

omap4_sdp4430_wifi_mux_init() is called by an __init marked function,
and only calls omap_mux_init_gpio() and omap_mux_init_signal() which
are both also an __init marked functions.

The only reason this doesn't issue a warning is because the compiler
inlines omap4_sdp4430_wifi_mux_init() into omap4_sdp4430_wifi_init().

So, lets add the __init annotation to ensure this remains safe should
the compiler choose not to inline.
Acked-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

WARNING: arch/arm/mach-omap2/built-in.o(.text+0x15a4): Section mismatch in reference from the function omap_mux_init_signals() to the function .init.text:omap_mux_init_signal()
The function omap_mux_init_signals() references
the function __init omap_mux_init_signal().
This is often because omap_mux_init_signals lacks a __init
annotation or the annotation of omap_mux_init_signal is wrong.
Acked-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

On my OMAP4 platform, I'm getting this error message repeated several
times at boot:

omap_vc_i2c_init: I2C config for all channels must match.
omap_vc_i2c_init: I2C config for all channels must match.

This doesn't help identify what the problem is.  Fix this message to
be more informative:

omap_vc_i2c_init: I2C config for vdd_iva does not match other channels (0).
omap_vc_i2c_init: I2C config for vdd_mpu does not match other channels (0).

This allows us to identify which voltage domains have a problem, and
what the I2C configuration state (a boolean, i2c_high_speed) setting
being used actually is.

From this we find that omap4_core_pmic has i2c_high_speed false, but
omap4_iva_pmic and omap4_mpu_pmic both have it set true.
Acked-by: NTony Lindgren <tony@atomide.com>
Acked-by: NKevin Hilman <khilman@ti.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

While testing on my OMAP3430 platform, this error message was emitted:

omap_vc_init_channel: PMIC info requried to configure vc forvdd_core not populated.Hence cannot initialize vc

Trying to find this message was difficult because it was wrapped across
several lines.  It also mis-spells "required", doesn't read very well,
and has spaces lacking.  Let's replace it with a more concise:

omap_vc_init_channel: No PMIC info for vdd_core

While we're here, fix a simple spelling error in a comment.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

When CONFIG_OF is disabled, the compile fails with:

arch/arm/mach-omap2/prm44xx.c:41: error: 'OMAP44XX_IRQ_PRCM' undeclared here (not in a function)
Acked-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Prevent OMAP UARTs from going idle while they are still transferring
data in PIO mode.  This works around an oversight in the OMAP UART
hardware present in OMAP34xx and earlier: an idle UART won't send a
wakeup when the TX FIFO threshold is reached.  This causes long delays
during data transmission when the MPU powerdomain enters a low-power
mode.  The MPU interrupt controller is not able to respond to
interrupts when it's in a low-power state, so the TX buffer is not
refilled until another wakeup event occurs.

This fix changes the erratum i291 DMA idle workaround.  Rather than
toggling between force-idle and no-idle, it will toggle between
smart-idle and no-idle.  The important part of the workaround is the
no-idle part, so this shouldn't result in any change in behavior.

This fix should work on all OMAP UARTs.  Future patches intended for
the 3.4 merge window will make this workaround conditional on a
"feature" flag, and will use the OMAP36xx+ TX event wakeup support.

Thanks to Kevin Hilman <khilman@ti.com> for mentioning the erratum i291
workaround, which led to the development of this approach.
Signed-off-by: NPaul Walmsley <paul@pwsan.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Acked-by: NGovindraj.R <govindraj.raja@ti.com>
Reviewed-by: NKevin Hilman <khilman@ti.com>
Tested-by: NKevin Hilman <khilman@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

When the PMIC is not found, voltdm->pmic will be NULL.  vp.c's
initialization function tries to dereferences this, which causes an
oops:

Unable to handle kernel NULL pointer dereference at virtual address 00000000
pgd = c0004000
[00000000] *pgd=00000000
Internal error: Oops: 5 [#1] PREEMPT
Modules linked in:
CPU: 0    Not tainted  (3.3.0-rc2+ #204)
PC is at omap_vp_init+0x5c/0x15c
LR is at omap_vp_init+0x58/0x15c
pc : [<c03db880>]    lr : [<c03db87c>]    psr: 60000013
sp : c181ff30  ip : c181ff68  fp : c181ff64
r10: c0407808  r9 : c040786c  r8 : c0407814
r7 : c0026868  r6 : c00264fc  r5 : c040ad6c  r4 : 00000000
r3 : 00000040  r2 : 000032c8  r1 : 0000fa00  r0 : 000032c8
Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment kernel
Control: 10c5387d  Table: 80004019  DAC: 00000015
Process swapper (pid: 1, stack limit = 0xc181e2e8)
Stack: (0xc181ff30 to 0xc1820000)
ff20:                                     c0381d00 c02e9c6d c0383582 c040786c
ff40: c040ad6c c00264fc c0026868 c0407814 00000000 c03d9de4 c181ff8c c181ff68
ff60: c03db448 c03db830 c02e982c c03fdfb8 c03fe004 c0039988 00000013 00000000
ff80: c181ff9c c181ff90 c03d9df8 c03db390 c181ffdc c181ffa0 c0008798 c03d9df0
ffa0: c181ffc4 c181ffb0 c0055a44 c0187050 c0039988 c03fdfb8 c03fe004 c0039988
ffc0: 00000013 00000000 00000000 00000000 c181fff4 c181ffe0 c03d1284 c0008708
ffe0: 00000000 c03d1208 00000000 c181fff8 c0039988 c03d1214 1077ce40 01f7ee08
Backtrace:
[<c03db824>] (omap_vp_init+0x0/0x15c) from [<c03db448>] (omap_voltage_late_init+0xc4/0xfc)
[<c03db384>] (omap_voltage_late_init+0x0/0xfc) from [<c03d9df8>] (omap2_common_pm_late_init+0x14/0x54)
 r8:00000000 r7:00000013 r6:c0039988 r5:c03fe004 r4:c03fdfb8
[<c03d9de4>] (omap2_common_pm_late_init+0x0/0x54) from [<c0008798>] (do_one_initcall+0x9c/0x164)
[<c00086fc>] (do_one_initcall+0x0/0x164) from [<c03d1284>] (kernel_init+0x7c/0x120)
[<c03d1208>] (kernel_init+0x0/0x120) from [<c0039988>] (do_exit+0x0/0x2cc)
 r5:c03d1208 r4:00000000
Code: e5ca300b e5900034 ebf69027 e5994024 (e5941000)
---[ end trace aed617dddaf32c3d ]---
Kernel panic - not syncing: Attempted to kill init!
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The ARM kernel uses undefined instructions to implement
BUG/BUG_ON(). This leads to problems where people don't read one
line above the Oops message and see the "kernel BUG at ..."
message and so they wrongly assume the kernel has hit an
undefined instruction.

Instead of printing:

 Internal error: Oops - undefined instruction: 0 [#1] PREEMPT SMP

print

 Internal error: Oops - BUG: 0 [#1] PREEMPT SMP

This should prevent people from thinking the BUG_ON was an
undefined instruction when it was actually intentional.
Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>
Acked-by: NSimon Glass <sjg@chromium.org>
Tested-by: NSimon Glass <sjg@chromium.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

armv7's flush_cache_all() flushes caches via set/way. To
determine the cache attributes (line size, number of sets,
etc.) the assembly first writes the CSSELR register to select a
cache level and then reads the CCSIDR register. The CSSELR register
is banked per-cpu and is used to determine which cache level CCSIDR
reads. If the task is migrated between when the CSSELR is written and
the CCSIDR is read the CCSIDR value may be for an unexpected cache
level (for example L1 instead of L2) and incorrect cache flushing
could occur.

Disable interrupts across the write and read so that the correct
cache attributes are read and used for the cache flushing
routine. We disable interrupts instead of disabling preemption
because the critical section is only 3 instructions and we want
to call v7_dcache_flush_all from __v7_setup which doesn't have a
full kernel stack with a struct thread_info.

This fixes a problem we see in scm_call() when flush_cache_all()
is called from preemptible context and sometimes the L2 cache is
not properly flushed out.
Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>
Acked-by: NCatalin Marinas <catalin.marinas@arm.com>
Reviewed-by: NNicolas Pitre <nico@linaro.org>
Cc: stable@vger.kernel.org
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

With an admittedly exotic choice of configuration options
(CC_OPTIMIZE_FOR_SIZE, THUMB2, some other size-minimizing ones)
and compiler, the proc_info table can end up being misaligned,
and the kernel being unbootable (Error: unrecognized/unsupported
processor variant).

Forcing the alignement to 4 bytes in the linker script fixes the
issue.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The following patch fixes a bug introduced by the following
commit:

        e050e3f0 ("perf: Fix broken interrupt rate throttling")

The patch caused the following warning to pop up depending on
the sampling frequency adjustments:

  ------------[ cut here ]------------
  WARNING: at arch/x86/kernel/cpu/perf_event.c:995 x86_pmu_start+0x79/0xd4()

It was caused by the following call sequence:

perf_adjust_freq_unthr_context.part() {
     stop()
     if (delta > 0) {
          perf_adjust_period() {
              if (period > 8*...) {
                  stop()
                  ...
                  start()
              }
          }
      }
      start()
}

Which caused a double start and a double stop, thus triggering
the assert in x86_pmu_start().

The patch fixes the problem by avoiding the double calls. We
pass a new argument to perf_adjust_period() to indicate whether
or not the event is already stopped. We can't just remove the
start/stop from that function because it's called from
__perf_event_overflow where the event needs to be reloaded via a
stop/start back-toback call.

The patch reintroduces the assertion in x86_pmu_start() which
was removed by commit:

	84f2b9b2 ("perf: Remove deprecated WARN_ON_ONCE()")

In this second version, we've added calls to disable/enable PMU
during unthrottling or frequency adjustment based on bug report
of spurious NMI interrupts from Eric Dumazet.
Reported-and-tested-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NStephane Eranian <eranian@google.com>
Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: markus@trippelsdorf.de
Cc: paulus@samba.org
Link: http://lkml.kernel.org/r/20120207133956.GA4932@quad
[ Minor edits to the changelog and to the code ]
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Upstream commit d1fce9c1

   "ARM: restart: bcmring: use new restart hook"

breaks building of this platform, since what used to be the
last field of the MACHINE_START/END block didn't have a
trailing comma.  Once another field was added below, we get:

arch/arm/mach-bcmring/arch.c:198: error: request for member 'restart' in something not a structure or union
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: NJiandong Zheng <jdzheng@broadcom.com>
Signed-off-by: NOlof Johansson <olof@lixom.net>

Remove BCMRING DMA map code which is no longer used.

This also fixes a build error with dma.c introduced by
bfcd2ea6.
Signed-off-by: NJiandong Zheng <jdzheng@broadcom.com>
Signed-off-by: NOlof Johansson <olof@lixom.net>

Enable use of the generic atomic64 implementation on AVR32 platforms.
Without this the kernel fails to build as the architecture does not
provide its version.
Signed-off-by: NFabio Baltieri <fabio.baltieri@gmail.com>
Acked-by: NHans-Christian Egtvedt <egtvedt@samfundet.no>
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Defining memscan() as memchr() is wrong, because the return values of
memscan() and memchr() are different when the character is not found.  So
use the generic memscan() implementation to fix this.
Signed-off-by: NAkinobu Mita <akinobu.mita@gmail.com>
Cc: Chris Zankel <chris@zankel.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

CC: stable@kernel.org #2.6.37 and onwards
Signed-off-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

When a user offlines a VCPU and then onlines it, we get:

NMI watchdog disabled (cpu2): hardware events not enabled
BUG: scheduling while atomic: swapper/2/0/0x00000002
Modules linked in: dm_multipath dm_mod xen_evtchn iscsi_boot_sysfs iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi scsi_mod libcrc32c crc32c radeon fbco
 ttm bitblit softcursor drm_kms_helper xen_blkfront xen_netfront xen_fbfront fb_sys_fops sysimgblt sysfillrect syscopyarea xen_kbdfront xenfs [last unloaded:

Pid: 0, comm: swapper/2 Tainted: G           O 3.2.0phase15.1-00003-gd6f7f5b-dirty #4
Call Trace:
 [<ffffffff81070571>] __schedule_bug+0x61/0x70
 [<ffffffff8158eb78>] __schedule+0x798/0x850
 [<ffffffff8158ed6a>] schedule+0x3a/0x50
 [<ffffffff810349be>] cpu_idle+0xbe/0xe0
 [<ffffffff81583599>] cpu_bringup_and_idle+0xe/0x10

The reason for this should be obvious from this call-chain:
cpu_bringup_and_idle:
 \- cpu_bringup
  |   \-[preempt_disable]
  |
  |- cpu_idle
       \- play_dead [assuming the user offlined the VCPU]
       |     \
       |     +- (xen_play_dead)
       |          \- HYPERVISOR_VCPU_off [so VCPU is dead, once user
       |          |                       onlines it starts from here]
       |          \- cpu_bringup [preempt_disable]
       |
       +- preempt_enable_no_reschedule()
       +- schedule()
       \- preempt_enable()

So we have two preempt_disble() and one preempt_enable(). Calling
preempt_enable() after the cpu_bringup() in the xen_play_dead
fixes the imbalance.
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>