Re-jig the CPU abort helpers to take the PC/PSR in r4/r5 rather
than r2/r3.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Tail-call the main C prefetch abort handler code from the per-CPU
helper code.  Also note that the helper function becomes ABI
compliant in terms of the registers preserved.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This avoids the irq entry assembly corrupting r5, thereby allowing it
to be preserved through to the svc exit code.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

All handlers now call trace_hardirqs_off, so move this common code into
the (svc|usr)_entry assembler macros.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

As we no longer re-enable interrupts in these exception handlers, add
the irqsoff tracing calls to them so that the kernel tracks the state
more accurately.

Note that these calls are conditional on IRQSOFF_TRACER:

  kernel ----------> user ---------> kernel
          ^ irqs enabled   ^ irqs disabled

No kernel code can run on the local CPU until we've re-entered the
kernel through one of the exception handlers - and userspace can not
take any locks etc.  So, the kernel doesn't care about the IRQ mask
state while userspace is running unless we're doing IRQ off latency
tracing.  So, we can (and do) avoid the overhead of updating the IRQ
mask state on every kernel->user and user->kernel transition.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Add irqtrace function calls to the undefined exception handler, so
that we get sane lockdep traces from locking problems in undefined
exception handlers.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Avoid enabling interrupts if the parent context had interrupts enabled
in the abort handler assembly code, and move this into the breakpoint/
page/alignment fault handlers instead.

This gets rid of some special-casing for the breakpoint fault handlers
from the low level abort handler path.
Acked-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This avoids unnecessary instructions for CPUs which implement the IFAR
(instruction fault address register).
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This allows us to avoid moving registers twice to work around the
clobbered registers when we add calls to trace_hardirqs_{on,off}.

Ensure that all SVC handlers return with SPSR in r5 for consistency.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

There's no point checking to see whether IRQs were masked in the parent
context when returning from IRQ handling - the fact that we're handling
an IRQ means that the parent context must have had IRQs unmasked.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

irq_enter() and irq_exit() already take care of the preempt_count
handling for interrupts, which increment and decrement the hardirq
bits of the preempt count.  So we can remove the preempt count handing
in our IRQ entry/exit assembly, like x86 did some 9 years ago.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

We can test bits 27:25 and 20 of the instruction at the same time;
there's no need to separate out the check of bit 20.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Require all callers of abort macros to specify the registers to be
used.  This improves the documentation at the callsites as to which
registers are being used by this assembly code.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Replace r4 with ip for calling abort helpers - ip is allowed to be
corrupted by called functions in the ABI, so it makes more sense to
use such a register.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Directly referencing registers in macros makes assembly code harder
to change, because the macros have side effects which are non-obvious.
Use the provided 'base' register rather than directly referencing r4.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Platforms provide an empty irq_prio_table macro, and as nothing uses
this macro, it can simply be removed.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

To make SLUB work on UML we need this_cpu_cmpxchg from
asm-generic/percpu.h.
Signed-off-by: NRichard Weinberger <richard@nod.at>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

commit 21a3c964 uses node_start/end_pfn(nid) for detection start/end
of nodes. But, it's not defined in linux/mmzone.h but defined in
/arch/???/include/mmzone.h which is included only under
CONFIG_NEED_MULTIPLE_NODES=y.

Then, we see
  mm/page_cgroup.c: In function 'page_cgroup_init':
  mm/page_cgroup.c:308: error: implicit declaration of function 'node_start_pfn'
  mm/page_cgroup.c:309: error: implicit declaration of function 'node_end_pfn'

So, fixiing page_cgroup.c is an idea...

But node_start_pfn()/node_end_pfn() is a very generic macro and
should be implemented in the same manner for all archs.
(m32r has different implementation...)

This patch removes definitions of node_start/end_pfn() in each archs
and defines a unified one in linux/mmzone.h. It's not under
CONFIG_NEED_MULTIPLE_NODES, now.

A result of macro expansion is here (mm/page_cgroup.c)

for !NUMA
 start_pfn = ((&contig_page_data)->node_start_pfn);
  end_pfn = ({ pg_data_t *__pgdat = (&contig_page_data); __pgdat->node_start_pfn + __pgdat->node_spanned_pages;});

for NUMA (x86-64)
  start_pfn = ((node_data[nid])->node_start_pfn);
  end_pfn = ({ pg_data_t *__pgdat = (node_data[nid]); __pgdat->node_start_pfn + __pgdat->node_spanned_pages;});

Changelog:
 - fixed to avoid using "nid" twice in node_end_pfn() macro.
Reported-and-acked-by: NRandy Dunlap <randy.dunlap@oracle.com>
Reported-and-tested-by: NIngo Molnar <mingo@elte.hu>
Acked-by: NMel Gorman <mgorman@suse.de>
Signed-off-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Ensure that the TLS register is saved and restored over a suspend
cycle, so that userspace programs don't see a corrupted TLS value.
Tested-by: NKevin Hilman <khilman@ti.com>
Acked-by: NJean Pihet <j-pihet@ti.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Add the missing suspend/resume pointers for the suspend code.  This
is needed when building for multiple CPUs.
Tested-by: NKevin Hilman <khilman@ti.com>
Acked-by: NJean Pihet <j-pihet@ti.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The bit shift operation in smp_ctl_set_bit does not specify the type
of the shifted bit so integer is used as default. Therefore it is not
possible to set bits in the upper 32 bit of the control register if
the kernel runs in 64 bit mode. Fix this by specifying the type as
unsigned long.
Signed-off-by: NJan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

The sampling interval for the hardware sampler is specified in cycles.
(see SA23-2260-01 The Load-Program-Parameter and the CPU-Measurement
Facilities)
The current default value will therefore result in millions of samples.
This patch changes the default sampling interval to 4M, which will
result in ~1500 samples per second on a z196 reducing the overhead
of sampling.
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

On specific configurations with hwsampler opcontrol --start returns an
error on "echo 1 >/dev/oprofile/enable". Turns out that the hw sampling
interval is not checked against the hardware limits.
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

A user can create the Kconfig combination !VIRTUALIZATION, S390_GUEST
which results in the following warnings:

warning: (S390_GUEST) selects VIRTIO which has unmet direct dependencies (VIRTUALIZATION)
warning: (S390_GUEST && VIRTIO_PCI && VIRTIO_BALLOON) selects VIRTIO_RING which has unmet direct dependencies (VIRTUALIZATION && VIRTIO)
warning: (S390_GUEST) selects VIRTIO which has unmet direct dependencies (VIRTUALIZATION)
warning: (S390_GUEST && VIRTIO_PCI && VIRTIO_BALLOON) selects VIRTIO_RING which has unmet direct dependencies (VIRTUALIZATION && VIRTIO)

S390_GUEST has to select VIRTUALIZATION before selecting VIRTIO and
friends.
Reported-by: NJan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

MN10300's asm/uaccess.h needs to #include linux/kernel.h to get might_sleep()
otherwise it fails to build on MN10300 allyesconfig.  This fails in a few
places with messages like the following:

  In file included from security/keys/trusted.c:14:
  include/linux/uaccess.h: In function '__copy_from_user_nocache':
  include/linux/uaccess.h:52: error: implicit declaration of function 'might_sleep'
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The iop13xx_defconfig didn't build since the platform code uses
defines from <asm/ptrace.h>. Simply add the include so it
compiles.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

It is easy to mis-maintain the proc_types table such that the
entries become wrongly-sized and misaligned when the kernel is
built in Thumb-2.

This patch adds an assembly-time check which will turn most common
size/alignment mistakes in this table into build failures, to avoid
having to debug the boot-time kernel hang which would happen if the
resulting kernel were actually booted.
Signed-off-by: NDave Martin <dave.martin@linaro.org>
Acked-by: NNicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

When we bring a CPU online, we should wait for it to become active
before entering the idle thread, so we know that the scheduler and
thread migration is going to work.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The DGT runs at 27 MHz divided by 4 on 8660 and 8960.
Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NDavid Brown <davidb@codeaurora.org>

The 128-bit multiply in pvclock.h was missing an output constraint for
EDX which caused a register corruption to appear.  Thanks to Ulrich for
diagnosing the EDX corruption and Avi for providing this fix.
Signed-off-by: NZachary Amsden <zamsden@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

The condition is opposite, it always maps huge page for the dirty tracked page
Reported-by: NSteve <stefan.bosak@gmail.com>
Signed-off-by: NSteve <stefan.bosak@gmail.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Only decache guest CR3 value if vcpu->arch.cr3 is stale.
Fixes loadvm with live guest.
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
Tested-by: NMarkus Schade <markus.schade@gmail.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

On 3.0-rc1 I get

In file included from arch/x86/kvm/mmu.c:2856:
arch/x86/kvm/paging_tmpl.h: In function ‘paging32_walk_addr_generic’:
arch/x86/kvm/paging_tmpl.h:124: warning: ‘ptep_user’ may be used uninitialized in this function
In file included from arch/x86/kvm/mmu.c:2852:
arch/x86/kvm/paging_tmpl.h: In function ‘paging64_walk_addr_generic’:
arch/x86/kvm/paging_tmpl.h:124: warning: ‘ptep_user’ may be used uninitialized in this function

caused by 6e2ca7d1. According to Takuya
Yoshikawa, ptep_user won't be used uninitialized so shut up gcc.

Cc: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Link: http://lkml.kernel.org/r/20110530094604.GC21833@liondog.tnicSigned-off-by: NBorislav Petkov <bp@alien8.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Commit 916f676f started reserving boot service code since some systems
require you to keep that code around until SetVirtualAddressMap is called.

However, in some cases those areas will overlap with reserved regions.
The proper medium-term fix is to fix the bootloader to prevent the
conflicts from occurring by moving the kernel to a better position,
but the kernel should check for this possibility, and only reserve regions
which can be reserved.
Signed-off-by: NMaarten Lankhorst <m.b.lankhorst@gmail.com>
Link: http://lkml.kernel.org/r/4DF7A005.1050407@gmail.comAcked-by: NMatthew Garrett <mjg@redhat.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Some msm targets have timers whose lower bits are unreliable. So, we
present our timers as lower frequency than they actually are, and ignore
the bottom 5 bits on such targets. This compensation was erroneously
removed from the msm_read_timer_count function, so restore it.

This was broken by 94790ec2 "msm: timer: SMP timer support for msm".
Signed-off-by: NJeff Ohlstein <johlstei@codeaurora.org>

The "Thumb bit" of a symbol is only really meaningful for function
symbols (STT_FUNC).

However, sometimes a branch is relocated against a non-function
symbol; for example, PC-relative branches to anonymous assembler
local symbols are typically fixed up against the start-of-section
symbol, which is not a function symbol.  Some inline assembler
generates references of this type, such as fixup code generated by
macros in <asm/uaccess.h>.

The existing relocation code for R_ARM_THM_CALL/R_ARM_THM_JUMP24
interprets this case as an error, because the target symbol appears
to be an ARM symbol; but this is really not the case, since the
target symbol is just a base in these cases.  The addend defines
the precise offset to the target location, but since the addend is
encoded in a non-interworking Thumb branch instruction, there is no
explicit Thumb bit in the addend.  Because these instructions never
interwork, the implied Thumb bit in the addend is 1, and the
destination is Thumb by definition.

This patch removes the extraneous Thumb bit check for non-function
symbols, enabling modules containing the affected relocation types
to be loaded.  No modification to the actual relocation code is
required, since this code does not take bit[0] of the
location->destination offset into account in any case.

Function symbols are always checked for interworking conflicts, as
before.
Signed-off-by: NDave Martin <dave.martin@linaro.org>
Acked-by: NCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The h7201/h7202 machines did not build since they define
ARM_DMA_ZONE_OFFSET but do not select ZONE_DMA. Fix it up by
selecting ZONE_DMA in their Kconfig.

Cc: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The assembly code in entry-macro-multi.S does not build without
the include asm/assembler.h in the case of CONFIG_SMP=y.

Fixes the rather theoretical SMP build of mach-shmobile/entry-intc.c:

arch/arm/include/asm/entry-macro-multi.S: Assembler messages:
arch/arm/include/asm/entry-macro-multi.S:20: Error: bad instruction `alt_smp(test_for_ipi r0,r6,r5,lr)'
arch/arm/include/asm/entry-macro-multi.S:20: Error: bad instruction `alt_up_b(9997f)'
make[1]: *** [arch/arm/mach-shmobile/entry-intc.o] Error 1
make: *** [arch/arm/mach-shmobile] Error 2
make: *** Waiting for unfinished jobs....
Signed-off-by: NMagnus Damm <damm@opensource.se>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The earlier attempts (24bdb0b6)
at fixing this problem caused other problems to surface (PV guests
with no PCI passthrough would have SWIOTLB turned on - which meant
64MB of precious contingous DMA32 memory being eaten up per guest).
The problem was: "on xen we add an extra memory region at the end of
the e820, and on this particular machine this extra memory region
would start below 4g and cross over the 4g boundary:

[0xfee01000-0x192655000)

Unfortunately e820_end_of_low_ram_pfn does not expect an
e820 layout like that so it returns 4g, therefore initial_memory_mapping
will map [0 - 0x100000000), that is a memory range that includes some
reserved memory regions."

The memory range was the IOAPIC regions, and with the 1-1 mapping
turned on, it would map them as RAM, not as MMIO regions. This caused
the hypervisor to complain. Fortunately this is experienced only under
the initial domain so we guard for it.
Acked-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>