Instead of exporting the very low-level internals of the FPU state
save/restore code (ie things like 'fpu_owner_task'), we should export
the higher-level interfaces.

Inlining these things is pointless anyway: sure, sometimes the end
result is small, but while 'stts()' can result in just three x86
instructions, those are not cheap instructions (writing %cr0 is a
serializing instruction and a very slow one at that).

So the overhead of a function call is not noticeable, and we really
don't want random modules mucking about with our internal state save
logic anyway.

So this unexports 'fpu_owner_task', and instead uninlines and exports
the actual functions that modules can use: fpu_kernel_begin/end() and
unlazy_fpu().
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1202211339590.5354@i5.linux-foundation.orgSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>

(And define it properly for x86-32, which had its 'current_task'
declaration in separate from x86-64)

Bitten by my dislike for modules on the machines I use, and the fact
that apparently nobody else actually wanted to test the patches I sent
out.

Snif. Nobody else cares.

Anyway, we probably should uninline the 'kernel_fpu_begin()' function
that is what modules actually use and that references this, but this is
the minimal fix for now.
Reported-by: NJosh Boyer <jwboyer@gmail.com>
Reported-and-tested-by: NJongman Heo <jongman.heo@samsung.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This makes us recognize when we try to restore FPU state that matches
what we already have in the FPU on this CPU, and avoids the restore
entirely if so.

To do this, we add two new data fields:

 - a percpu 'fpu_owner_task' variable that gets written any time we
   update the "has_fpu" field, and thus acts as a kind of back-pointer
   to the task that owns the CPU.  The exception is when we save the FPU
   state as part of a context switch - if the save can keep the FPU
   state around, we leave the 'fpu_owner_task' variable pointing at the
   task whose FP state still remains on the CPU.

 - a per-thread 'last_cpu' field, that indicates which CPU that thread
   used its FPU on last.  We update this on every context switch
   (writing an invalid CPU number if the last context switch didn't
   leave the FPU in a lazily usable state), so we know that *that*
   thread has done nothing else with the FPU since.

These two fields together can be used when next switching back to the
task to see if the CPU still matches: if 'fpu_owner_task' matches the
task we are switching to, we know that no other task (or kernel FPU
usage) touched the FPU on this CPU in the meantime, and if the current
CPU number matches the 'last_cpu' field, we know that this thread did no
other FP work on any other CPU, so the FPU state on the CPU must match
what was saved on last context switch.

In that case, we can avoid the 'f[x]rstor' entirely, and just clear the
CR0.TS bit.
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This inlines what is usually just a couple of instructions, but more
importantly it also fixes the theoretical error case (can that FPU
restore really ever fail? Maybe we should remove the checking).

We can't start sending signals from within the scheduler, we're much too
deep in the kernel and are holding the runqueue lock etc.  So don't
bother even trying.
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This makes sure we clear the FPU usage counter for newly created tasks,
just so that we start off in a known state (for example, don't try to
preload the FPU state on the first task switch etc).

It also fixes a thinko in when we increment the fpu_counter at task
switch time, introduced by commit 34ddc81a ("i387: re-introduce FPU
state preloading at context switch time").  We should increment the
*new* task fpu_counter, not the old task, and only if we decide to use
that state (whether lazily or preloaded).
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

After all the FPU state cleanups and finally finding the problem that
caused all our FPU save/restore problems, this re-introduces the
preloading of FPU state that was removed in commit b3b0870e ("i387:
do not preload FPU state at task switch time").

However, instead of simply reverting the removal, this reimplements
preloading with several fixes, most notably

 - properly abstracted as a true FPU state switch, rather than as
   open-coded save and restore with various hacks.

   In particular, implementing it as a proper FPU state switch allows us
   to optimize the CR0.TS flag accesses: there is no reason to set the
   TS bit only to then almost immediately clear it again.  CR0 accesses
   are quite slow and expensive, don't flip the bit back and forth for
   no good reason.

 - Make sure that the same model works for both x86-32 and x86-64, so
   that there are no gratuitous differences between the two due to the
   way they save and restore segment state differently due to
   architectural differences that really don't matter to the FPU state.

 - Avoid exposing the "preload" state to the context switch routines,
   and in particular allow the concept of lazy state restore: if nothing
   else has used the FPU in the meantime, and the process is still on
   the same CPU, we can avoid restoring state from memory entirely, just
   re-expose the state that is still in the FPU unit.

   That optimized lazy restore isn't actually implemented here, but the
   infrastructure is set up for it.  Of course, older CPU's that use
   'fnsave' to save the state cannot take advantage of this, since the
   state saving also trashes the state.

In other words, there is now an actual _design_ to the FPU state saving,
rather than just random historical baggage.  Hopefully it's easier to
follow as a result.
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This moves the bit that indicates whether a thread has ownership of the
FPU from the TS_USEDFPU bit in thread_info->status to a word of its own
(called 'has_fpu') in task_struct->thread.has_fpu.

This fixes two independent bugs at the same time:

 - changing 'thread_info->status' from the scheduler causes nasty
   problems for the other users of that variable, since it is defined to
   be thread-synchronous (that's what the "TS_" part of the naming was
   supposed to indicate).

   So perfectly valid code could (and did) do

	ti->status |= TS_RESTORE_SIGMASK;

   and the compiler was free to do that as separate load, or and store
   instructions.  Which can cause problems with preemption, since a task
   switch could happen in between, and change the TS_USEDFPU bit. The
   change to TS_USEDFPU would be overwritten by the final store.

   In practice, this seldom happened, though, because the 'status' field
   was seldom used more than once, so gcc would generally tend to
   generate code that used a read-modify-write instruction and thus
   happened to avoid this problem - RMW instructions are naturally low
   fat and preemption-safe.

 - On x86-32, the current_thread_info() pointer would, during interrupts
   and softirqs, point to a *copy* of the real thread_info, because
   x86-32 uses %esp to calculate the thread_info address, and thus the
   separate irq (and softirq) stacks would cause these kinds of odd
   thread_info copy aliases.

   This is normally not a problem, since interrupts aren't supposed to
   look at thread information anyway (what thread is running at
   interrupt time really isn't very well-defined), but it confused the
   heck out of irq_fpu_usable() and the code that tried to squirrel
   away the FPU state.

   (It also caused untold confusion for us poor kernel developers).

It also turns out that using 'task_struct' is actually much more natural
for most of the call sites that care about the FPU state, since they
tend to work with the task struct for other reasons anyway (ie
scheduling).  And the FPU data that we are going to save/restore is
found there too.

Thanks to Arjan Van De Ven <arjan@linux.intel.com> for pointing us to
the %esp issue.

Cc: Arjan van de Ven <arjan@linux.intel.com>
Reported-and-tested-by: NRaphael Prevost <raphael@buro.asia>
Acked-and-tested-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Tested-by: NPeter Anvin <hpa@zytor.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The conversion of the ktime to a value suitable for the clock comparator
does not take changes to wall_to_monotonic into account. In fact the
conversion just needs the boot clock (sched_clock_base_cc) and the
total_sleep_time.

This is applicable to 3.2+ kernels.

CC: stable@vger.kernel.org
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

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>

perf on POWER stopped working after commit e050e3f0 (perf: Fix
broken interrupt rate throttling). That patch exposed a bug in
the POWER perf_events code.

Since the PMCs count upwards and take an exception when the top bit
is set, we want to write 0x80000000 - left in power_pmu_start. We were
instead programming in left which effectively disables the counter
until we eventually hit 0x80000000. This could take seconds or longer.

With the patch applied I get the expected number of samples:

          SAMPLE events:       9948
Signed-off-by: NAnton Blanchard <anton@samba.org>
Acked-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: <stable@kernel.org>

Program Check exceptions are the result of WARNs, BUGs, some
type of breakpoints, kprobe, and other illegal instructions.

We want interrupts (and thus preemption) to remain disabled
while doing the initial stage of testing the reason and
branching off to a debugger or kprobe, so we are still on
the original CPU which makes debugging easier in various cases.

This is how the code was intended, hence the local_irq_enable()
right in the middle of program_check_exception().

However, the assembly exception prologue for that exception was
incorrectly marked as enabling interrupts, which defeats that
(and records a redundant enable with lockdep).
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Since we are heading towards removing the Legacy iSeries platform, start
by no longer building it for ppc64_defconfig.
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Upstream changes to the way PHB resources are registered
broke the resource fixup for FSL boards.

We can no longer rely on the resource pointer array for the PHB's
pci_bus structure, so let's leave it alone and go straight for
the PHB resources instead. This also makes the code generally
more readable.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

A kernel oops/panic prints an instruction dump showing several
instructions before and after the instruction which caused the
oops/panic.

The code intended that the faulting instruction be enclosed in angle
brackets, however a bug caused the faulting instruction to be
interpreted by printk() as the message log level.

To fix this, the KERN_CONT log level is added before the actual text of
the printed message.

=== Before the patch ===

[ 1081.587266] Instruction dump:
[ 1081.590236] 7c000110 7c0000f8 5400077c 552907f6 7d290378 992b0003 4e800020 38000001
[ 1081.598034] 3d20c03a 9009a114 7c0004ac 39200000
[ 1081.602500]  4e800020 3803ffd0 2b800009

<4>[ 1081.587266] Instruction dump:
<4>[ 1081.590236] 7c000110 7c0000f8 5400077c 552907f6 7d290378 992b0003 4e800020 38000001
<4>[ 1081.598034] 3d20c03a 9009a114 7c0004ac 39200000
<98090000>[ 1081.602500]  4e800020 3803ffd0 2b800009

=== After the patch ===

[   51.385216] Instruction dump:
[   51.388186] 7c000110 7c0000f8 5400077c 552907f6 7d290378 992b0003 4e800020 38000001
[   51.395986] 3d20c03a 9009a114 7c0004ac 39200000 <98090000> 4e800020 3803ffd0 2b800009

<4>[   51.385216] Instruction dump:
<4>[   51.388186] 7c000110 7c0000f8 5400077c 552907f6 7d290378 992b0003 4e800020 38000001
<4>[   51.395986] 3d20c03a 9009a114 7c0004ac 39200000 <98090000> 4e800020 3803ffd0 2b800009
Signed-off-by: NIra W. Snyder <iws@ovro.caltech.edu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.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>

Driver at91_ide is broken and should not be fixed: remove it.
Modification of device files that where making use of it. The
PATA driver (pata_at91) is able to replace at91_ide.
Signed-off-by: NJean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Acked-by: NNicolas Ferre <nicolas.ferre@atmel.com>

SMC, Static Memory Controller will need more accessors to fine
configure its parameters.
Signed-off-by: NJean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Acked-by: NNicolas Ferre <nicolas.ferre@atmel.com>

Registration of at91_udc as a module will enable SoC
related code.

Fix following an idea from Karel Znamenacek.
Signed-off-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: NKarel Znamenacek <karel@ryston.cz>
Acked-by: NJean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Cc: stable <stable@vger.kernel.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>