otherwise we will get for some user-space applications
that use 'clone' with CLONE_CHILD_SETTID | CLONE_CHILD_CLEARTID
end up hitting an assert in glibc manifested by:

general protection ip:7f80720d364c sp:7fff98fd8a80 error:0 in
libc-2.13.so[7f807209e000+180000]

This is due to the nature of said operations which sets and clears
the PID.  "In the successful one I can see that the page table of
the parent process has been updated successfully to use a
different physical page, so the write of the tid on
that page only affects the child...

On the other hand, in the failed case, the write seems to happen before
the copy of the original page is done, so both the parent and the child
end up with the same value (because the parent copies the page after
the write of the child tid has already happened)."
(Roger's analysis). The nature of this is due to the Xen's commit
of 51e2cac257ec8b4080d89f0855c498cbbd76a5e5
"x86/pvh: set only minimal cr0 and cr4 flags in order to use paging"
the CR0_WP was removed so COW features of the Linux kernel were not
operating properly.

While doing that also update the rest of the CR0 flags to be inline
with what a baremetal Linux kernel would set them to.

In 'secondary_startup_64' (baremetal Linux) sets:

X86_CR0_PE | X86_CR0_MP | X86_CR0_ET | X86_CR0_NE | X86_CR0_WP |
X86_CR0_AM | X86_CR0_PG

The hypervisor for HVM type guests (which PVH is a bit) sets:
X86_CR0_PE | X86_CR0_ET | X86_CR0_TS
For PVH it specifically sets:
X86_CR0_PG

Which means we need to set the rest: X86_CR0_MP | X86_CR0_NE  |
X86_CR0_WP | X86_CR0_AM to have full parity.
Signed-off-by: NRoger Pau Monne <roger.pau@citrix.com>
Signed-off-by: NMukesh Rathor <mukesh.rathor@oracle.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
[v1: Took out the cr4 writes to be a seperate patch]
[v2: 0-DAY kernel found xen_setup_gdt to be missing a static]

The usage of 'select' means it will enable the CONFIG
options without checking their dependencies. That meant
we would inadvertently turn on CONFIG_XEN_PVHM while its
core dependency (CONFIG_PCI) was turned off.

This patch fixes the warnings and compile failures:

warning: (XEN_PVH) selects XEN_PVHVM which has unmet direct
dependencies (HYPERVISOR_GUEST && XEN && PCI && X86_LOCAL_APIC)
Reported-by: NJim Davis <jim.epost@gmail.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

Remove duplicated include.
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

Oddly enough it compiles for my ancient compiler but with
the supplied .config it does blow up. Fix is easy enough.
Reported-by: Nkbuild test robot <fengguang.wu@intel.com>
Reported-by: NJim Davis <jim.epost@gmail.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

PVH allows PV linux guest to utilize hardware extended capabilities,
such as running MMU updates in a HVM container.

The Xen side defines PVH as (from docs/misc/pvh-readme.txt,
with modifications):

"* the guest uses auto translate:
 - p2m is managed by Xen
 - pagetables are owned by the guest
 - mmu_update hypercall not available
* it uses event callback and not vlapic emulation,
* IDT is native, so set_trap_table hcall is also N/A for a PVH guest.

For a full list of hcalls supported for PVH, see pvh_hypercall64_table
in arch/x86/hvm/hvm.c in xen.  From the ABI prespective, it's mostly a
PV guest with auto translate, although it does use hvm_op for setting
callback vector."

Use .ascii and .asciz to define xen feature string. Note, the PVH
string must be in a single line (not multiple lines with \) to keep the
assembler from putting null char after each string before \.
This patch allows it to be configured and enabled.

We also use introduce the 'XEN_ELFNOTE_SUPPORTED_FEATURES' ELF note to
tell the hypervisor that 'hvm_callback_vector' is what the kernel
needs. We can not put it in 'XEN_ELFNOTE_FEATURES' as older hypervisor
parse fields they don't understand as errors and refuse to load
the kernel. This work-around fixes the problem.
Signed-off-by: NMukesh Rathor <mukesh.rathor@oracle.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>

In PVH the shared grant frame is the PFN and not MFN,
hence its mapped via the same code path as HVM.

The allocation of the grant frame is done differently - we
do not use the early platform-pci driver and have an
ioremap area - instead we use balloon memory and stitch
all of the non-contingous pages in a virtualized area.

That means when we call the hypervisor to replace the GMFN
with a XENMAPSPACE_grant_table type, we need to lookup the
old PFN for every iteration instead of assuming a flat
contingous PFN allocation.

Lastly, we only use v1 for grants. This is because PVHVM
is not able to use v2 due to no XENMEM_add_to_physmap
calls on the error status page (see commit
69e8f430
 xen/granttable: Disable grant v2 for HVM domains.)

Until that is implemented this workaround has to
be in place.

Also per suggestions by Stefano utilize the PVHVM paths
as they share common functionality.

v2 of this patch moves most of the PVH code out in the
arch/x86/xen/grant-table driver and touches only minimally
the generic driver.

v3, v4: fixes us some of the code due to earlier patches.
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>

The 'xen_hvm_resume_frames' used to be an 'unsigned long'
and contain the virtual address of the grants. That was OK
for most architectures (PVHVM, ARM) were the grants are contiguous
in memory. That however is not the case for PVH - in which case
we will have to do a lookup for each virtual address for the PFN.

Instead of doing that, lets make it a structure which will contain
the array of PFNs, the virtual address and the count of said PFNs.

Also provide a generic functions: gnttab_setup_auto_xlat_frames and
gnttab_free_auto_xlat_frames to populate said structure with
appropriate values for PVHVM and ARM.

To round it off, change the name from 'xen_hvm_resume_frames' to
a more descriptive one - 'xen_auto_xlat_grant_frames'.

For PVH, in patch "xen/pvh: Piggyback on PVHVM for grant driver"
we will populate the 'xen_auto_xlat_grant_frames' by ourselves.

v2 moves the xen_remap in the gnttab_setup_auto_xlat_frames
and also introduces xen_unmap for gnttab_free_auto_xlat_frames.
Suggested-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
[v3: Based on top of 'asm/xen/page.h: remove redundant semicolon']
Acked-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>

PVH is a PV guest with a twist - there are certain things
that work in it like HVM and some like PV. There is
a similar mode - PVHVM where we run in HVM mode with
PV code enabled - and this patch explores that.

The most notable PV interfaces are the XenBus and event channels.

We will piggyback on how the event channel mechanism is
used in PVHVM - that is we want the normal native IRQ mechanism
and we will install a vector (hvm callback) for which we
will call the event channel mechanism.

This means that from a pvops perspective, we can use
native_irq_ops instead of the Xen PV specific. Albeit in the
future we could support pirq_eoi_map. But that is
a feature request that can be shared with PVHVM.
Signed-off-by: NMukesh Rathor <mukesh.rathor@oracle.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: NDavid Vrabel <david.vrabel@citrix.com>
Acked-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>

In xen_add_extra_mem() we can skip updating P2M as it's managed
by Xen. PVH maps the entire IO space, but only RAM pages need
to be repopulated.
Signed-off-by: NMukesh Rathor <mukesh.rathor@oracle.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: NDavid Vrabel <david.vrabel@citrix.com>
Acked-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>

The VCPU bringup protocol follows the PV with certain twists.
From xen/include/public/arch-x86/xen.h:

Also note that when calling DOMCTL_setvcpucontext and VCPU_initialise
for HVM and PVH guests, not all information in this structure is updated:

 - For HVM guests, the structures read include: fpu_ctxt (if
 VGCT_I387_VALID is set), flags, user_regs, debugreg[*]

 - PVH guests are the same as HVM guests, but additionally use ctrlreg[3] to
 set cr3. All other fields not used should be set to 0.

This is what we do. We piggyback on the 'xen_setup_gdt' - but modify
a bit - we need to call 'load_percpu_segment' so that 'switch_to_new_gdt'
can load per-cpu data-structures. It has no effect on the VCPU0.

We also piggyback on the %rdi register to pass in the CPU number - so
that when we bootup a new CPU, the cpu_bringup_and_idle will have
passed as the first parameter the CPU number (via %rdi for 64-bit).
Signed-off-by: NMukesh Rathor <mukesh.rathor@oracle.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

During early bootup we start life using the Xen provided
GDT, which means that we are running with %cs segment set
to FLAT_KERNEL_CS (FLAT_RING3_CS64 0xe033, GDT index 261).

But for PVH we want to be use HVM type mechanism for
segment operations. As such we need to switch to the HVM
one and also reload ourselves with the __KERNEL_CS:eip
to run in the proper GDT and segment.

For HVM this is usually done in 'secondary_startup_64' in
(head_64.S) but since we are not taking that bootup
path (we start in PV - xen_start_kernel) we need to do
that in the early PV bootup paths.

For good measure we also zero out the %fs, %ds, and %es
(not strictly needed as Xen has already cleared them
for us). The %gs is loaded by 'switch_to_new_gdt'.
Signed-off-by: NMukesh Rathor <mukesh.rathor@oracle.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: NDavid Vrabel <david.vrabel@citrix.com>

For PVHVM the shared_info structure is provided via the same way
as for normal PV guests (see include/xen/interface/xen.h).

That is during bootup we get 'xen_start_info' via the %esi register
in startup_xen. Then later we extract the 'shared_info' from said
structure (in xen_setup_shared_info) and start using it.

The 'xen_setup_shared_info' is all setup to work with auto-xlat
guests, but there are two functions which it calls that are not:
xen_setup_mfn_list_list and xen_setup_vcpu_info_placement.
This patch modifies the P2M code (xen_setup_mfn_list_list)
while the "Piggyback on PVHVM for event channels" modifies
the xen_setup_vcpu_info_placement.
Signed-off-by: NMukesh Rathor <mukesh.rathor@oracle.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

We also optimize one - the TLB flush. The native operation would
needlessly IPI offline VCPUs causing extra wakeups. Using the
Xen one avoids that and lets the hypervisor determine which
VCPU needs the TLB flush.
Signed-off-by: NMukesh Rathor <mukesh.rathor@oracle.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

.. which are surprisingly small compared to the amount for PV code.

PVH uses mostly native mmu ops, we leave the generic (native_*) for
the majority and just overwrite the baremetal with the ones we need.

At startup, we are running with pre-allocated page-tables
courtesy of the tool-stack. But we still need to graft them
in the Linux initial pagetables. However there is no need to
unpin/pin and change them to R/O or R/W.

Note that the xen_pagetable_init due to 7836fec9d0994cc9c9150c5a33f0eb0eb08a335a
"xen/mmu/p2m: Refactor the xen_pagetable_init code." does not
need any changes - we just need to make sure that xen_post_allocator_init
does not alter the pvops from the default native one.
Signed-off-by: NMukesh Rathor <mukesh.rathor@oracle.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>

Stefano noticed that the code runs only under 64-bit so
the comments about 32-bit are pointless.

Also we change the condition for xen_revector_p2m_tree
returning the same value (because it could not allocate
a swath of space to put the new P2M in) or it had been
called once already. In such we return early from the
function.
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>

The revectoring and copying of the P2M only happens when
!auto-xlat and on 64-bit builds. It is not obvious from
the code, so lets have seperate 32 and 64-bit functions.

We also invert the check for auto-xlat to make the code
flow simpler.
Suggested-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

P2M is not available for PVH. Fortunatly for us the
P2M code already has mostly the support for auto-xlat guest thanks to
commit 3d24bbd7
"grant-table: call set_phys_to_machine after mapping grant refs"
which: "
introduces set_phys_to_machine calls for auto_translated guests
(even on x86) in gnttab_map_refs and gnttab_unmap_refs.
translated by swiotlb-xen... " so we don't need to muck much.

with above mentioned "commit you'll get set_phys_to_machine calls
from gnttab_map_refs and gnttab_unmap_refs but PVH guests won't do
anything with them " (Stefano Stabellini) which is OK - we want
them to be NOPs.

This is because we assume that an "IOMMU is always present on the
plaform and Xen is going to make the appropriate IOMMU pagetable
changes in the hypercall implementation of GNTTABOP_map_grant_ref
and GNTTABOP_unmap_grant_ref, then eveything should be transparent
from PVH priviligied point of view and DMA transfers involving
foreign pages keep working with no issues[sp]

Otherwise we would need a P2M (and an M2P) for PVH priviligied to
track these foreign pages .. (see arch/arm/xen/p2m.c)."
(Stefano Stabellini).

We still have to inhibit the building of the P2M tree.
That had been done in the past by not calling
xen_build_dynamic_phys_to_machine (which setups the P2M tree
and gives us virtual address to access them). But we are missing
a check for xen_build_mfn_list_list - which was continuing to setup
the P2M tree and would blow up at trying to get the virtual
address of p2m_missing (which would have been setup by
xen_build_dynamic_phys_to_machine).

Hence a check is needed to not call xen_build_mfn_list_list when
running in auto-xlat mode.

Instead of replicating the check for auto-xlat in enlighten.c
do it in the p2m.c code. The reason is that the xen_build_mfn_list_list
is called also in xen_arch_post_suspend without any checks for
auto-xlat. So for PVH or PV with auto-xlat - we would needlessly
allocate space for an P2M tree.
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: NDavid Vrabel <david.vrabel@citrix.com>
Acked-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>

We don't use the filtering that 'xen_cpuid' is doing
because the hypervisor treats 'XEN_EMULATE_PREFIX' as
an invalid instruction. This means that all of the filtering
will have to be done in the hypervisor/toolstack.

Without the filtering we expose to the guest the:

 - cpu topology (sockets, cores, etc);
 - the APERF (which the generic scheduler likes to
    use), see  5e626254
    "xen/setup: filter APERFMPERF cpuid feature out"
 - and the inability to figure out whether MWAIT_LEAF
   should be exposed or not. See
   df88b2d9
   "xen/enlighten: Disable MWAIT_LEAF so that acpi-pad won't be loaded."
 - x2apic, see  4ea9b9ac
   "xen: mask x2APIC feature in PV"

We also check for vector callback early on, as it is a required
feature. PVH also runs at default kernel IOPL.

Finally, pure PV settings are moved to a separate function that are
only called for pure PV, ie, pv with pvmmu. They are also #ifdef
with CONFIG_XEN_PVMMU.
Signed-off-by: NMukesh Rathor <mukesh.rathor@oracle.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>

Which is a PV guest with auto page translation enabled
and with vector callback. It is a cross between PVHVM and PV.

The Xen side defines PVH as (from docs/misc/pvh-readme.txt,
with modifications):

"* the guest uses auto translate:
 - p2m is managed by Xen
 - pagetables are owned by the guest
 - mmu_update hypercall not available
* it uses event callback and not vlapic emulation,
* IDT is native, so set_trap_table hcall is also N/A for a PVH guest.

For a full list of hcalls supported for PVH, see pvh_hypercall64_table
in arch/x86/hvm/hvm.c in xen.  From the ABI prespective, it's mostly a
PV guest with auto translate, although it does use hvm_op for setting
callback vector."

Also we use the PV cpuid, albeit we can use the HVM (native) cpuid.
However, we do have a fair bit of filtering in the xen_cpuid and
we can piggyback on that until the hypervisor/toolstack filters
the appropiate cpuids. Once that is done we can swap over to
use the native one.

We setup a Kconfig entry that is disabled by default and
cannot be enabled.

Note that on ARM the concept of PVH is non-existent. As Ian
put it: "an ARM guest is neither PV nor HVM nor PVHVM.
It's a bit like PVH but is different also (it's further towards
the H end of the spectrum than even PVH).". As such these
options (PVHVM, PVH) are never enabled nor seen on ARM
compilations.
Signed-off-by: NMukesh Rathor <mukesh.rathor@oracle.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

Most of the functions in page.h are prefaced with
	if (xen_feature(XENFEAT_auto_translated_physmap))
		return mfn;

Except the mfn_to_local_pfn. At a first sight, the function
should work without this patch - as the 'mfn_to_mfn' has
a similar check. But there are no such check in the
'get_phys_to_machine' function - so we would crash in there.

This fixes it by following the convention of having the
check for auto-xlat in these static functions.
Signed-off-by: NMukesh Rathor <mukesh.rathor@oracle.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>

Commit bee980d9 (xen/events: Handle VIRQ_TIMER before any other hardirq
in event loop) effectively made the VIRQ_TIMER the highest priority event
when using the 2-level ABI.

Set the VIRQ_TIMER priority to the highest so this behaviour is retained
when using the FIFO-based ABI.
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>
Reviewed-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>

Signed-off-by: NWei Liu <liuw@liuw.name>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>

Since we have  xen_has_pv_devices,xen_has_pv_disk_devices,
xen_has_pv_nic_devices, and xen_has_pv_and_legacy_disk_devices
to figure out the different 'unplug' behaviors - lets
use those instead of this single int.
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

The user has the option of disabling the platform driver:
00:02.0 Unassigned class [ff80]: XenSource, Inc. Xen Platform Device (rev 01)

which is used to unplug the emulated drivers (IDE, Realtek 8169, etc)
and allow the PV drivers to take over. If the user wishes
to disable that they can set:

  xen_platform_pci=0
  (in the guest config file)

or
  xen_emul_unplug=never
  (on the Linux command line)

except it does not work properly. The PV drivers still try to
load and since the Xen platform driver is not run - and it
has not initialized the grant tables, most of the PV drivers
stumble upon:

input: Xen Virtual Keyboard as /devices/virtual/input/input5
input: Xen Virtual Pointer as /devices/virtual/input/input6M
------------[ cut here ]------------
kernel BUG at /home/konrad/ssd/konrad/linux/drivers/xen/grant-table.c:1206!
invalid opcode: 0000 [#1] SMP
Modules linked in: xen_kbdfront(+) xenfs xen_privcmd
CPU: 6 PID: 1389 Comm: modprobe Not tainted 3.13.0-rc1upstream-00021-ga6c892b-dirty #1
Hardware name: Xen HVM domU, BIOS 4.4-unstable 11/26/2013
RIP: 0010:[<ffffffff813ddc40>]  [<ffffffff813ddc40>] get_free_entries+0x2e0/0x300
Call Trace:
 [<ffffffff8150d9a3>] ? evdev_connect+0x1e3/0x240
 [<ffffffff813ddd0e>] gnttab_grant_foreign_access+0x2e/0x70
 [<ffffffffa0010081>] xenkbd_connect_backend+0x41/0x290 [xen_kbdfront]
 [<ffffffffa0010a12>] xenkbd_probe+0x2f2/0x324 [xen_kbdfront]
 [<ffffffff813e5757>] xenbus_dev_probe+0x77/0x130
 [<ffffffff813e7217>] xenbus_frontend_dev_probe+0x47/0x50
 [<ffffffff8145e9a9>] driver_probe_device+0x89/0x230
 [<ffffffff8145ebeb>] __driver_attach+0x9b/0xa0
 [<ffffffff8145eb50>] ? driver_probe_device+0x230/0x230
 [<ffffffff8145eb50>] ? driver_probe_device+0x230/0x230
 [<ffffffff8145cf1c>] bus_for_each_dev+0x8c/0xb0
 [<ffffffff8145e7d9>] driver_attach+0x19/0x20
 [<ffffffff8145e260>] bus_add_driver+0x1a0/0x220
 [<ffffffff8145f1ff>] driver_register+0x5f/0xf0
 [<ffffffff813e55c5>] xenbus_register_driver_common+0x15/0x20
 [<ffffffff813e76b3>] xenbus_register_frontend+0x23/0x40
 [<ffffffffa0015000>] ? 0xffffffffa0014fff
 [<ffffffffa001502b>] xenkbd_init+0x2b/0x1000 [xen_kbdfront]
 [<ffffffff81002049>] do_one_initcall+0x49/0x170

.. snip..

which is hardly nice. This patch fixes this by having each
PV driver check for:
 - if running in PV, then it is fine to execute (as that is their
   native environment).
 - if running in HVM, check if user wanted 'xen_emul_unplug=never',
   in which case bail out and don't load any PV drivers.
 - if running in HVM, and if PCI device 5853:0001 (xen_platform_pci)
   does not exist, then bail out and not load PV drivers.
 - (v2) if running in HVM, and if the user wanted 'xen_emul_unplug=ide-disks',
   then bail out for all PV devices _except_ the block one.
   Ditto for the network one ('nics').
 - (v2) if running in HVM, and if the user wanted 'xen_emul_unplug=unnecessary'
   then load block PV driver, and also setup the legacy IDE paths.
   In (v3) make it actually load PV drivers.

Reported-by: Sander Eikelenboom <linux@eikelenboom.it
Reported-by: NAnthony PERARD <anthony.perard@citrix.com>
Reported-and-Tested-by: NFabio Fantoni <fabio.fantoni@m2r.biz>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
[v2: Add extra logic to handle the myrid ways 'xen_emul_unplug'
can be used per Ian and Stefano suggestion]
[v3: Make the unnecessary case work properly]
[v4: s/disks/ide-disks/ spotted by Fabio]
Reviewed-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com> [for PCI parts]
CC: stable@vger.kernel.org

After commit 88f718e3
"ARM: pxa: delete the custom GPIO header" a compilation
error was introduced in the PXA25x gadget driver.
An attempt to fix the problem was made in
commit b144e4ab
"usb: gadget: fix pxa25x compilation problems"
by explictly stating the driver needs the <mach/hardware.h>
header, which solved the compilation for a few boards,
such as the pxa255-idp and its defconfig.

However the Lubbock board has this special clause in
drivers/usb/gadget/pxa25x_udc.c:

This include file has an implicit dependency on
<mach/irqs.h> having been included before <mach/lubbock.h>
was included.

Before commit 88f718e3
"ARM: pxa: delete the custom GPIO header" this implicit
dependency for the pxa25x_udc compile on the Lubbock was
satisfied by <linux/gpio.h> implicitly including
<mach/gpio.h> which was in turn including <mach/irqs.h>,
apart from the earlier added <mach/hardware.h>.

Fix this by having the PXA25x <mach/lubbock.h> explicitly
include <mach/irqs.h>.
Reported-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Cc: Greg Kroah-Hartmann <gregkh@linuxfoundation.org>
Cc: Felipe Balbi <balbi@ti.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NHaojian Zhuang <haojian.zhuang@gmail.com>
Signed-off-by: NOlof Johansson <olof@lixom.net>

Looks like the LCD panel on LDP has been broken quite a while, and
recently got fixed by commit 0b2aa8be (gpio: twl4030: Fix regression
for twl gpio output). However, there's still an issue left where the panel
backlight does not come on if the LCD drivers are built into the
kernel.

Fix the issue by registering the DPI LCD panel only after the twl4030
GPIO has probed.
Reported-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Acked-by: NTomi Valkeinen <tomi.valkeinen@ti.com>
[tony@atomide.com: updated per Tomi's comments]
Signed-off-by: NTony Lindgren <tony@atomide.com>

Commit 7d7e1eba (ARM: OMAP2+: Prepare for irqs.h removal) and commit
ec2c0825 (ARM: OMAP2+: Remove hardcoded IRQs and enable SPARSE_IRQ)
updated the way interrupts for OMAP2/3 devices are defined in the
HWMOD data structures to being an index plus a fixed offset (defined
by OMAP_INTC_START).

Couple of irqs in the OMAP2/3 hwmod data were misconfigured completely
as they were missing this OMAP_INTC_START relative offset. Add this
offset back to fix the incorrect irq data for the following modules:
	OMAP2 - GPMC, RNG
	OMAP3 - GPMC, ISP MMU & IVA MMU
Signed-off-by: NSuman Anna <s-anna@ti.com>
Fixes: 7d7e1eba ("ARM: OMAP2+: Prepare for irqs.h removal")
Fixes: ec2c0825 ("ARM: OMAP2+: Remove hardcoded IRQs and enable SPARSE_IRQ")
Cc: Tony Lindgren <tony@atomide.com>
Signed-off-by: NPaul Walmsley <paul@pwsan.com>

With commit '7dedd346: ARM: OMAP2+: hwmod: Fix a crash in _setup_reset() with
 DEBUG_LL' we moved from parsing cmdline to identify uart used for earlycon
to using the requsite hwmod CONFIG_DEBUG_OMAPxUARTy FLAGS.

On DRA7 though, we seem to be missing this flag, and atleast on the DRA7 EVM
where we use uart1 for console, boot fails with DEBUG_LL enabled.
Reported-by: NLokesh Vutla <lokeshvutla@ti.com>
Tested-by:  Lokesh Vutla <lokeshvutla@ti.com> # on a different base
Signed-off-by: NRajendra Nayak <rnayak@ti.com>
Fixes: 7dedd346 ("ARM: OMAP2+: hwmod: Fix a crash in _setup_reset() with DEBUG_LL")
Signed-off-by: NPaul Walmsley <paul@pwsan.com>

Linux 3.10 changed the timing of how thread_info->flags is touched:

	x86: Use generic idle loop
	(7d1a9417)

This caused Intel NHM-EX and WSM-EX servers to experience a large number
of immediate MONITOR/MWAIT break wakeups, which caused cpuidle to demote
from deep C-states to shallow C-states, which caused these platforms
to experience a significant increase in idle power.

Note that this issue was already present before the commit above,
however, it wasn't seen often enough to be noticed in power measurements.

Here we extend an errata workaround from the Core2 EX "Dunnington"
to extend to NHM-EX and WSM-EX, to prevent these immediate
returns from MWAIT, reducing idle power on these platforms.

While only acpi_idle ran on Dunnington, intel_idle
may also run on these two newer systems.
As of today, there are no other models that are known
to need this tweak.

Link: http://lkml.kernel.org/r/CAJvTdK=%2BaNN66mYpCGgbHGCHhYQAKx-vB0kJSWjVpsNb_hOAtQ@mail.gmail.comSigned-off-by: NLen Brown <len.brown@intel.com>
Link: http://lkml.kernel.org/r/baff264285f6e585df757d58b17788feabc68918.1387403066.git.len.brown@intel.com
Cc: <stable@vger.kernel.org> # 3.12.x, 3.11.x, 3.10.x
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

Commit 8f34a1da ("arm64: ptrace: use HW_BREAKPOINT_EMPTY type for
disabled breakpoints") fixed an issue with GDB trying to zero breakpoint
control registers. The problem there is that the arch hw_breakpoint code
will attempt to create a (disabled), execute breakpoint of length 0.

This will fail validation and report unexpected failure to GDB. To avoid
this, we treated disabled breakpoints as HW_BREAKPOINT_EMPTY, but that
seems to have broken with recent kernels, causing watchpoints to be
treated as TYPE_INST in the core code and returning ENOSPC for any
further breakpoints.

This patch fixes the problem by prioritising the `enable' field of the
breakpoint: if it is cleared, we simply update the perf_event_attr to
indicate that the thing is disabled and don't bother changing either the
type or the length. This reinforces the behaviour that the breakpoint
control register is essentially read-only apart from the enable bit
when disabling a breakpoint.

Cc: <stable@vger.kernel.org>
Reported-by: NAaron Liu <liucy214@gmail.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Commit 97bc386f "ARC: Add guard macro to uapi/asm/unistd.h"
inhibited multiple inclusion of ARCH unistd.h. This however hosed the system
since Generic syscall table generator relies on it being included twice,
and in lack-of an empty table was emitted by C preprocessor.

Fix that by allowing one exception to rule for the special case (just
like Xtensa)
Suggested-by: NChen Gang <gang.chen.5i5j@gmail.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

The r8a7790.dtsi file has four sdhi nodes which the first two have the wrong
resource size for their register block. This causes the sh_modbile_sdhi driver
to fail to communicate with card at-all.

Change sdhi{0,1} node size from 0x100 to 0x200 to correct these nodes
as per Kuninori Morimoto's response to the original patch where all four
nodes where changed. sdhi{2,3} are the correct size.

This bug has been present since sdhi resources were added to the r8a7790 by
8c9b1aa4 ("ARM: shmobile: r8a7790: add MMCIF and SDHI DT
templates") in v3.11-rc2.
Signed-off-by: NBen Dooks <ben.dooks@codethink.co.uk>
Tested-by: NWilliam Towle <william.towle@codethink.co.uk>
Acked-by: NKuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: NSimon Horman <horms+renesas@verge.net.au>

4dcfa600
(ARM: DMA-API: better handing of DMA masks for coherent allocations)
exchanged DMA mask check method.
Below warning will appear without this patch

asoc-simple-card asoc-simple-card.0: \
  Coherent DMA mask 0xffffffffffffffff is larger than dma_addr_t allows
asoc-simple-card asoc-simple-card.0: \
  Driver did not use or check the return value from dma_set_coherent_mask()?
Signed-off-by: NKuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NSimon Horman <horms+renesas@verge.net.au>

Commit 22ceeee1 ("pwm-backlight: Add
power supply support") added a mandatory power supply for the PWM
backlight. Add a fixed 5V regulator to board code with a consumer supply
entry for the backlight device.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: NSimon Horman <horms+renesas@verge.net.au>
(cherry picked from commit ad11cb9a5cf96346f1240995c672cdbb5501785c)
Signed-off-by: NSimon Horman <horms+renesas@verge.net.au>

E.g. landisk_defconfig, which has CONFIG_NTFS_FS=m:

  ERROR: "__ashrdi3" [fs/ntfs/ntfs.ko] undefined!

For "lib-y", if no symbols in a compilation unit are referenced by other
units, the compilation unit will not be included in vmlinux.  This
breaks modules that do reference those symbols.

Use "obj-y" instead to fix this.

http://kisskb.ellerman.id.au/kisskb/buildresult/8838077/

This doesn't fix all cases. There are others, e.g. udivsi3.
This is also not limited to sh, many architectures handle this in the
same way.

A simple solution is to unconditionally include all helper functions.
A more complex solution is to make the choice of "lib-y" or "obj-y" depend
on CONFIG_MODULES:

  obj-$(CONFIG_MODULES) += ...
  lib-y($CONFIG_MODULES) += ...
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Tested-by: NNobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Reviewed-by: NNobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

There are a few subtle races, between change_protection_range (used by
mprotect and change_prot_numa) on one side, and NUMA page migration and
compaction on the other side.

The basic race is that there is a time window between when the PTE gets
made non-present (PROT_NONE or NUMA), and the TLB is flushed.

During that time, a CPU may continue writing to the page.

This is fine most of the time, however compaction or the NUMA migration
code may come in, and migrate the page away.

When that happens, the CPU may continue writing, through the cached
translation, to what is no longer the current memory location of the
process.

This only affects x86, which has a somewhat optimistic pte_accessible.
All other architectures appear to be safe, and will either always flush,
or flush whenever there is a valid mapping, even with no permissions
(SPARC).

The basic race looks like this:

CPU A			CPU B			CPU C

						load TLB entry
make entry PTE/PMD_NUMA
			fault on entry
						read/write old page
			start migrating page
			change PTE/PMD to new page
						read/write old page [*]
flush TLB
						reload TLB from new entry
						read/write new page
						lose data

[*] the old page may belong to a new user at this point!

The obvious fix is to flush remote TLB entries, by making sure that
pte_accessible aware of the fact that PROT_NONE and PROT_NUMA memory may
still be accessible if there is a TLB flush pending for the mm.

This should fix both NUMA migration and compaction.

[mgorman@suse.de: fix build]
Signed-off-by: NRik van Riel <riel@redhat.com>
Signed-off-by: NMel Gorman <mgorman@suse.de>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Base pages are unmapped and flushed from cache and TLB during normal
page migration and replaced with a migration entry that causes any
parallel NUMA hinting fault or gup to block until migration completes.

THP does not unmap pages due to a lack of support for migration entries
at a PMD level.  This allows races with get_user_pages and
get_user_pages_fast which commit 3f926ab9 ("mm: Close races between
THP migration and PMD numa clearing") made worse by introducing a
pmd_clear_flush().

This patch forces get_user_page (fast and normal) on a pmd_numa page to
go through the slow get_user_page path where it will serialise against
THP migration and properly account for the NUMA hinting fault.  On the
migration side the page table lock is taken for each PTE update.
Signed-off-by: NMel Gorman <mgorman@suse.de>
Reviewed-by: NRik van Riel <riel@redhat.com>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit caaa4c80 ("KVM: PPC: Book3S HV: Fix physical address
calculations") unfortunately resulted in some low-order address bits
getting dropped in the case where the guest is creating a 4k HPTE
and the host page size is 64k.  By getting the low-order bits from
hva rather than gpa we miss out on bits 12 - 15 in this case, since
hva is at page granularity.  This puts the missing bits back in.
Reported-by: NAlexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NAlexander Graf <agraf@suse.de>

We don't use PACATOC for PR. Avoid updating HOST_R2 with PR
KVM mode when both HV and PR are enabled in the kernel. Without this we
get the below crash

(qemu)
Unable to handle kernel paging request for data at address 0xffffffffffff8310
Faulting instruction address: 0xc00000000001d5a4
cpu 0x2: Vector: 300 (Data Access) at [c0000001dc53aef0]
    pc: c00000000001d5a4: .vtime_delta.isra.1+0x34/0x1d0
    lr: c00000000001d760: .vtime_account_system+0x20/0x60
    sp: c0000001dc53b170
   msr: 8000000000009032
   dar: ffffffffffff8310
 dsisr: 40000000
  current = 0xc0000001d76c62d0
  paca    = 0xc00000000fef1100   softe: 0        irq_happened: 0x01
    pid   = 4472, comm = qemu-system-ppc
enter ? for help
[c0000001dc53b200] c00000000001d760 .vtime_account_system+0x20/0x60
[c0000001dc53b290] c00000000008d050 .kvmppc_handle_exit_pr+0x60/0xa50
[c0000001dc53b340] c00000000008f51c kvm_start_lightweight+0xb4/0xc4
[c0000001dc53b510] c00000000008cdf0 .kvmppc_vcpu_run_pr+0x150/0x2e0
[c0000001dc53b9e0] c00000000008341c .kvmppc_vcpu_run+0x2c/0x40
[c0000001dc53ba50] c000000000080af4 .kvm_arch_vcpu_ioctl_run+0x54/0x1b0
[c0000001dc53bae0] c00000000007b4c8 .kvm_vcpu_ioctl+0x478/0x730
[c0000001dc53bca0] c0000000002140cc .do_vfs_ioctl+0x4ac/0x770
[c0000001dc53bd80] c0000000002143e8 .SyS_ioctl+0x58/0xb0
[c0000001dc53be30] c000000000009e58 syscall_exit+0x0/0x98
Signed-off-by: NAlexander Graf <agraf@suse.de>

Commit e30b06f4 (ARM: OMAP2+: Remove
legacy mux code for display.c) removed non-DT DSI and HDMI pinmuxing.
However, DSI pinmuxing is still needed, and removing that caused DSI
displays not to work.

This reverts the DSI parts of the commit.
Signed-off-by: NTomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>