This is used from set_fixmap() and clear_fixmap() via asm-generic/fixmap.h.
Also makes sure that the fixmap allocation fits into the expected range.

Based on patch by Rabin Vincent.
Signed-off-by: NKees Cook <keescook@chromium.org>
Cc: Rabin Vincent <rabin@rab.in>
Acked-by: NNicolas Pitre <nico@linaro.org>

With commit a05e54c1 ("ARM: 8031/2: change fixmap mapping region to
support 32 CPUs"), the fixmap region was expanded to 2MB, but it
precluded any other uses of the fixmap region. In order to support other
uses the fixmap region needs to be expanded beyond 2MB. Fortunately, the
adjacent 1MB range 0xffe00000-0xfff00000 is availabe.

Remove fixmap_page_table ptr and lookup the page table via the virtual
address so that the fixmap region can span more that one pmd. The 2nd
pmd is already created since it is shared with the vector page.
Signed-off-by: NRob Herring <robh@kernel.org>
[kees: fixed CONFIG_DEBUG_HIGHMEM get_fixmap() calls]
[kees: moved pte allocation outside of CONFIG_HIGHMEM]
Signed-off-by: NKees Cook <keescook@chromium.org>
Acked-by: NNicolas Pitre <nico@linaro.org>

Add further comments to the early page table remap code to explain what
the code is doing, why it is doing it, but more importantly to explain
that the code is not architecturally compliant and is squarely in
"UNPREDICTABLE" behaviour territory.

Add a warning and tainting of the kernel too.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

If init_mm.brk is not section aligned, the LPAE fixup code will miss
updating the final PMD.  Fix this by aligning map_end.

Fixes: a77e0c7b ("ARM: mm: Recreate kernel mappings in early_paging_init()")
Cc: <stable@vger.kernel.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This does the same as the previous commit, but for the S bit, which also
needs to match the initial value which the assembly code used for the
same reasons.  Again, we add a check for SMP to ensure that the page
tables are correctly setup for SMP.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Fix a long standing bug where, for ARMv6+, we don't fully ensure that
the C code sets the same cache policy as the assembly code.  This was
introduced partially by commit 11179d8c ([ARM] 4497/1: Only allow
safe cache configurations on ARMv6 and later) and also by adding SMP
support.

This patch sets the default cache policy based on the flags used by the
assembly code, and then ensures that when a cache policy command line
argument is used, we verify that on ARMv6, it matches the initial setup.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

adjust_cr() is not used anymore, so let's get rid of it.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Keep all bits of alignment handling together.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Several places open-code this manipulation, let's consolidate this.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

memblock is now fully integrated into the kernel and is the prefered
method for tracking memory. Rather than reinvent the wheel with
meminfo, migrate to using memblock directly instead of meminfo as
an intermediate.
Acked-by: NJason Cooper <jason@lakedaemon.net>
Acked-by: NCatalin Marinas <catalin.marinas@arm.com>
Acked-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: NKukjin Kim <kgene.kim@samsung.com>
Tested-by: NMarek Szyprowski <m.szyprowski@samsung.com>
Tested-by: NLeif Lindholm <leif.lindholm@linaro.org>
Signed-off-by: NLaura Abbott <lauraa@codeaurora.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

dsb st can be used to ensure completion of pending cache maintenance
operations, so use it for the v7 cache maintenance operations.
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

In 32-bit ARM systems, the fixmap mapping region can support no more
than 14 CPUs(total: 896k; one CPU: 64K). And we can configure NR_CPUS
up to 32. So there is a mismatch.

This patch moves fixmapping region downwards to region 0xffc00000-
0xffe00000. Then the fixmap mapping region can support up to 32 CPUs.
Reviewed-by: NNicolas Pitre <nico@linaro.org>
Signed-off-by: NLiu Hua <sdu.liu@huawei.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

CPU_32v6 currently selects CPU_USE_DOMAINS if CPU_V6 and MMU. This is
because ARM 1136 r0pX CPUs lack the v6k extensions, and therefore do
not have hardware thread registers. The lack of these registers requires
the kernel to update the vectors page at each context switch in order to
write a new TLS pointer. This write must be done via the userspace
mapping, since aliasing caches can lead to expensive flushing when using
kmap. Finally, this requires the vectors page to be mapped r/w for
kernel and r/o for user, which has implications for things like put_user
which must trigger CoW appropriately when targetting user pages.

The upshot of all this is that a v6/v7 kernel makes use of domains to
segregate kernel and user memory accesses. This has the nasty
side-effect of making device mappings executable, which has been
observed to cause subtle bugs on recent cores (e.g. Cortex-A15
performing a speculative instruction fetch from the GIC and acking an
interrupt in the process).

This patch solves this problem by removing the remaining domain support
from ARMv6. A new memory type is added specifically for the vectors page
which allows that page (and only that page) to be mapped as user r/o,
kernel r/w. All other user r/o pages are mapped also as kernel r/o.
Patch co-developed with Russell King.

Cc: <stable@vger.kernel.org>
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The stage-2 memory attributes are distinct from the Hyp memory
attributes and the Stage-1 memory attributes.  We were using the stage-1
memory attributes for stage-2 mappings causing device mappings to be
mapped as normal memory.  Add the S2 equivalent defines for memory
attributes and fix the comments explaining the defines while at it.

Add a prot_pte_s2 field to the mem_type struct and fill out the field
for device mappings accordingly.

Cc: <stable@vger.kernel.org>	[3.9+]
Acked-by: NMarc Zyngier <marc.zyngier@arm.com>
Acked-by: NCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NChristoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The CMA region was being marked executable:

0xdc04e000-0xdc050000           8K     RW x      MEM/CACHED/WBRA
0xdc060000-0xdc100000         640K     RW x      MEM/CACHED/WBRA
0xdc4f5000-0xdc500000          44K     RW x      MEM/CACHED/WBRA
0xdcce9000-0xe0000000       52316K     RW x      MEM/CACHED/WBRA

This is mainly due to the badly worded MT_MEMORY_DMA_READY symbol, but
there are also a few other places in dma-mapping which should be
corrected to use the right constant.  Fix all these places:

0xdc04e000-0xdc050000           8K     RW NX     MEM/CACHED/WBRA
0xdc060000-0xdc100000         640K     RW NX     MEM/CACHED/WBRA
0xdc280000-0xdc300000         512K     RW NX     MEM/CACHED/WBRA
0xdc6fc000-0xe0000000       58384K     RW NX     MEM/CACHED/WBRA
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Other architectures define various set_memory functions to allow
attributes to be changed (e.g. set_memory_x, set_memory_rw, etc.)
Currently, these functions are missing on ARM. Define these in an
appropriate manner for ARM.
Signed-off-by: NLaura Abbott <lauraa@codeaurora.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Add basic NX support for kernel lowmem mappings.  We mark any section
which does not overlap kernel text as non-executable, preventing it
from being used to write code and then execute directly from there.

This does not change the alignment of the sections, so the kernel
image doesn't grow significantly via this change, so we can do this
without needing a config option.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Document the permissions which the various MT_MEMORY* mapping types
will provide.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

ECC policy can be applied to the whole system
when this bit is implemented by SoC vendor
(IMP - bit 9 - in L1 page table entry format).
When this bit is not implemented by SoC vendor
it doesn't mean that system has no other way
how to do ECC.
This patch ensures to show this message only when ECC
is requested via cmd line ecc=on and runs on
appropriate ARM core.
Signed-off-by: NMichal Simek <michal.simek@xilinx.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This patch adds a step in the init sequence, in order to recreate
the kernel code/data page table mappings prior to full paging
initialization.  This is necessary on LPAE systems that run out of
a physical address space outside the 4G limit.  On these systems,
this implementation provides a machine descriptor hook that allows
the PHYS_OFFSET to be overridden in a machine specific fashion.

Cc: Russell King <linux@arm.linux.org.uk>
Acked-by: NNicolas Pitre <nico@linaro.org>
Signed-off-by: NR Sricharan <r.sricharan@ti.com>
Signed-off-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>

If kuser helpers are not provided by the kernel, disable user access to
the vectors page.  With the kuser helpers gone, there is no reason for
this page to be visible to userspace.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Move the machine vector stubs into the page above the vector page,
which we can prevent from being visible to userspace.  Also move
the reset stub, and place the swi vector at a location that the
'ldr' can get to it.

This hides pointers into the kernel which could give valuable
information to attackers, and reduces the number of exploitable
instructions at a fixed address.

Cc: <stable@vger.kernel.org>
Acked-by: NNicolas Pitre <nico@linaro.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

struct machine_desc records are defined everywhere as a 'const'
structure, but unfortuantely it loses its const-ness through the use of
linker magic - the symbols which surround the section are not declared
const so it becomes possible not to use 'const' for pointers to these
const structures.

Let's fix this oversight - all pointers to these structures should be
marked const too.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

When map_lowmem() runs, and processes a memory bank whose start or end
is not section-aligned, memory must be allocated to store the 2nd-level
page tables. Those allocations are made by calling memblock_alloc().

At this point, the only memory that is free *and* mapped is memory which
has already been mapped by map_lowmem() itself. For this reason, we must
calculate the first point at which map_lowmem() will need to allocate
memory, and set the memblock allocation limit to a lower address, so that
memblock_alloc() is guaranteed to return memory that is already mapped.

This patch enhances sanity_check_meminfo() to calculate that memory
address, and pass it to memblock_set_current_limit(), rather than just
assuming the limit is arm_lowmem_limit.

The algorithm applied is:

* Default memblock_limit to arm_lowmem_limit in the absence of any other
  limit; arm_lowmem_limit is the highest memory that is mapped by
  map_lowmem().

* While walking the list of memblocks, if the start of a block is not
  aligned, 2nd-level page tables will need to be allocated to map the
  first few pages of the block. Hence, the memblock_limit must be before
  the start of the block.

* Similarly, if the end of any block is not aligned, 2nd-level page
  tables will need to be allocated to map the last few pages of the
  block. Hence, the memblock_limit must point at the end of the block,
  rounded down to section-alignment.

* The memory blocks are assumed to be sorted in address order, so the
  first unaligned block start or end is used to set the limit.

With this algorithm, the start or end of almost any bank can be non-
section-aligned. The only exception is that the start of bank 0 must
be section-aligned, since otherwise memory would need to be allocated
when mapping the start of bank 0, which occurs before any free memory
is mapped.

[swarren, wrote commit description, rewrote calculation of memblock_limit]
Signed-off-by: NStephen Warren <swarren@nvidia.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Failure to add the mapping created in debug_ll_io_init() can lead
to the BUG_ON() triggering in lib/ioremap.c:27 if the static
virtual address decided for the debug_ll mapping overlaps with
another mapping that is created later. This happens because the
generic ioremap code has no idea there is a mapping there and it
tries to place a mapping in the same location and blows up when
it sees that there is a pte already present.

kernel BUG at lib/ioremap.c:27!
Internal error: Oops - BUG: 0 [#1] PREEMPT SMP ARM
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.10.0-rc2-00042-g2af0c67-dirty #316
task: ef088000 ti: ef082000 task.ti: ef082000
PC is at ioremap_page_range+0x16c/0x198
LR is at ioremap_page_range+0xf0/0x198
pc : [<c04cb874>]    lr : [<c04cb7f8>]    psr: 20000113
sp : ef083e78  ip : af140000  fp : ef083ebc
r10: ef7fc100  r9 : ef7fc104  r8 : 000af174
r7 : 00000647  r6 : beffffff  r5 : f004c000  r4 : f0040000
r3 : af173417  r2 : 16440653  r1 : af173e07  r0 : ef7fc8fc
Flags: nzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment kernel
Control: 10c5787d  Table: 8020406a  DAC: 00000015
Process swapper/0 (pid: 1, stack limit = 0xef082238)
Stack: (0xef083e78 to 0xef084000)
3e60:                                                       00040000 ef083eec
3e80: bf134000 f004bfff c0207c00 f004c000 c02fc120 f000c000 c15e7800 00040000
3ea0: ef083eec 00000647 c098ba9c c0953544 ef083edc ef083ec0 c021b82c c04cb714
3ec0: c09cdc50 00000040 ef0f1e00 ef1003c0 ef083f14 ef083ee0 c09535bc c021b7bc
3ee0: c0953544 c04d0c6c c094e2cc c1600be4 c07440c4 c09a6888 00000002 c0a15f00
3f00: ef082000 00000000 ef083f54 ef083f18 c0208728 c0953550 00000002 c1600bfc
3f20: c08e3fac c0839918 ef083f54 c1600b80 c09a6888 c0a15f00 0000008b c094e2cc
3f40: c098ba9c c098bab8 ef083f94 ef083f58 c094ea0c c020865c 00000002 00000002
3f60: c094e2cc 00000000 c025b674 00000000 c06ff860 00000000 00000000 00000000
3f80: 00000000 00000000 ef083fac ef083f98 c06ff878 c094e910 00000000 00000000
3fa0: 00000000 ef083fb0 c020efe8 c06ff86c 00000000 00000000 00000000 00000000
3fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
3fe0: 00000000 00000000 00000000 00000000 00000013 00000000 00000000 c0595108
[<c04cb874>] (ioremap_page_range+0x16c/0x198) from [<c021b82c>] (__alloc_remap_buffer.isra.18+0x7c/0xc4)
[<c021b82c>] (__alloc_remap_buffer.isra.18+0x7c/0xc4) from [<c09535bc>] (atomic_pool_init+0x78/0x128)
[<c09535bc>] (atomic_pool_init+0x78/0x128) from [<c0208728>] (do_one_initcall+0xd8/0x198)
[<c0208728>] (do_one_initcall+0xd8/0x198) from [<c094ea0c>] (kernel_init_freeable+0x108/0x1d0)
[<c094ea0c>] (kernel_init_freeable+0x108/0x1d0) from [<c06ff878>] (kernel_init+0x18/0xf4)
[<c06ff878>] (kernel_init+0x18/0xf4) from [<c020efe8>] (ret_from_fork+0x14/0x20)
Code: e50b0040 ebf54b2f e51b0040 eaffffee (e7f001f2)

Fix it by telling generic layers about the static mapping via
iotable_init().  This also has the nice side effect of letting
you see the mapping in procfs' vmallocinfo file.

Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Stephen Warren <swarren@nvidia.com>
Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This bug was introduced in commit e651eab0.
Some v4/v5 platforms failed to boot due to this.
Signed-off-by: NPo-Yu Chuang <ratbert.chuang@gmail.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This patch cleans up the highmem sanity check code by simplifying the range
checks with a pre-calculated size_limit.  This patch should otherwise have no
functional impact on behavior.

This patch also removes a redundant (bank->start < vmalloc_limit) check, since
this is already covered by the !highmem condition.
Signed-off-by: NCyril Chemparathy <cyril@ti.com>
Signed-off-by: NVitaly Andrianov <vitalya@ti.com>
Acked-by: NNicolas Pitre <nico@linaro.org>
Tested-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: NSubash Patel <subash.rp@samsung.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

On Keystone platforms, physical memory is entirely outside the 32-bit
addressible range.  Therefore, the (bank->start > ULONG_MAX) check below marks
the entire system memory as highmem, and this causes unpleasentness all over.

This patch eliminates the extra bank start check (against ULONG_MAX) by
checking bank->start against the physical address corresponding to vmalloc_min
instead.

In the process, this patch also cleans up parts of the highmem sanity check
code by removing what has now become a redundant check for banks that entirely
overlap with the vmalloc range.
Signed-off-by: NCyril Chemparathy <cyril@ti.com>
Signed-off-by: NVitaly Andrianov <vitalya@ti.com>
Acked-by: NNicolas Pitre <nico@linaro.org>
Tested-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: NSubash Patel <subash.rp@samsung.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

This patch modifies the highmem sanity checking code to use physical addresses
instead.  This change eliminates the wrap-around problems associated with the
original virtual address based checks, and this simplifies the code a bit.

The one constraint imposed here is that low physical memory must be mapped in
a monotonically increasing fashion if there are multiple banks of memory,
i.e., x < y must => pa(x) < pa(y).
Signed-off-by: NCyril Chemparathy <cyril@ti.com>
Signed-off-by: NVitaly Andrianov <vitalya@ti.com>
Acked-by: NNicolas Pitre <nico@linaro.org>
Tested-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: NSubash Patel <subash.rp@samsung.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

This patch fixes the alloc_init_pud() function to use phys_addr_t instead of
unsigned long when passing in the phys argument.

This is an extension to commit 97092e0c (ARM:
pgtable: use phys_addr_t for physical addresses), which applied similar changes
elsewhere in the ARM memory management code.
Signed-off-by: NVitaly Andrianov <vitalya@ti.com>
Signed-off-by: NCyril Chemparathy <cyril@ti.com>
Acked-by: NNicolas Pitre <nico@linaro.org>
Acked-by: NCatalin Marinas <catalin.marinas@arm.com>
Tested-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: NSubash Patel <subash.rp@samsung.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

More and more sub-architectures are using only the debug_ll_io_init
function as the map_io function. Make the core code call this function
if no function is specified in the machine description to remove some
boilerplate code.
Signed-off-by: NMaxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: NRob Herring <rob.herring@calxeda.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>

tcm_init() call iotable_init() and it use early_alloc variants which
do memblock allocation. Directly using memblock allocation after
initializing bootmem should not permitted, because bootmem can't know
where are additinally reserved.
So move tcm_init() to a safe place before initalizing bootmem.

(On the U300)
Tested-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NJoonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

With LPAE enabled, alloc_init_section() does not map the entire
address space for unaligned addresses.

The issue also reproduced with CMA + LPAE. CMA tries to map 16MB
with page granularity mappings during boot. alloc_init_pte()
is called and out of 16MB, only 2MB gets mapped and rest remains
unaccessible.

Because of this OMAP5 boot is broken with CMA + LPAE enabled.
Fix the issue by ensuring that the entire addresses are
mapped.
Signed-off-by: NR Sricharan <r.sricharan@ti.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christoffer Dall <chris@cloudcar.com>
Cc: Santosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: NLaura Abbott <lauraa@codeaurora.org>
Acked-by: NCatalin Marinas <catalin.marinas@arm.com>
Acked-by: NChristoffer Dall <chris@cloudcar.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

869486d5f51 (ARM: 7646/1: mm: use static_vm for managing static mapped
areas) introduced new warnings:

arch/arm/mm/mmu.c: In function 'pci_reserve_io':
arch/arm/mm/mmu.c:888:16: warning: unused variable 'addr'
arch/arm/mm/mmu.c:887:20: warning: unused variable 'vm'

because it failed to delete the two local variables it no longer used.
Fix this.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

A static mapped area is ARM-specific, so it is better not to use
generic vmalloc data structure, that is, vmlist and vmlist_lock
for managing static mapped area. And it causes some needless overhead and
reducing this overhead is better idea.

Now, we have newly introduced static_vm infrastructure.
With it, we don't need to iterate all mapped areas. Instead, we just
iterate static mapped areas. It helps to reduce an overhead of finding
matched area. And architecture dependency on vmalloc layer is removed,
so it will help to maintainability for vmalloc layer.
Reviewed-by: NNicolas Pitre <nico@linaro.org>
Acked-by: NRob Herring <rob.herring@calxeda.com>
Tested-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: NJoonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This makes cr_alignment a constant 0 to break code that tries to modify
the value as it's likely that it's built on wrong assumption when
CONFIG_CPU_CP15 isn't defined. For code that is only reading the value 0
is more or less a fine value to report.
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Message-Id: 1358413196-5609-2-git-send-email-u.kleine-koenig@pengutronix.de (v8)

KVM uses the stage-2 page tables and the Hyp page table format,
so we define the fields and page protection flags needed by KVM.

The nomenclature is this:
 - page_hyp:        PL2 code/data mappings
 - page_hyp_device: PL2 device mappings (vgic access)
 - page_s2:         Stage-2 code/data page mappings
 - page_s2_device:  Stage-2 device mappings (vgic access)
Reviewed-by: NWill Deacon <will.deacon@arm.com>
Reviewed-by: NMarcelo Tosatti <mtosatti@redhat.com>
Christoffer Dall <c.dall@virtualopensystems.com>

Commit 8fb54284 {ARM: mm: Add strongly ordered descriptor support}
added XN flag at section level but missed it at PTE level.

Fix it by adding the L_PTE_XN to MT_MEMORY_SO PTE descriptor.
Reported-by: NRichard Woodruff <r-woodruff2@ti.com>
Signed-off-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

When updating the page protection map after calculating the user_pgprot
value, the base protection map is temporarily stored in an unsigned long
type, causing truncation of the protection bits when LPAE is enabled.
This effectively means that calls to mprotect() will corrupt the upper
page attributes, clearing the XN bit unconditionally.

This patch uses pteval_t to store the intermediate protection values,
preserving the upper bits for 64-bit descriptors.

Cc: stable@vger.kernel.org
Acked-by: NNicolas Pitre <nico@linaro.org>
Acked-by: NCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

When using DEBUG_LL, the UART's (or other HW's) registers are mapped
into early page tables based on the results of assembly macro addruart.
Later, when the page tables are replaced, the same virtual address must
remain valid. Historically, this has been ensured by using defines from
<mach/iomap.h> in both the implementation of addruart, and the machine's
.map_io() function. However, with the move to single zImage, we wish to
remove <mach/iomap.h>. To enable this, the macro addruart may be used
when constructing the late page tables too; addruart is exposed as a
C function debug_ll_addr(), and used to set up the required mapping in
debug_ll_io_init(), which may called on an opt-in basis from a machine's
.map_io() function.
Signed-off-by: NRob Herring <rob.herring@calxeda.com>
[swarren: Mask map.virtual with PAGE_MASK. Checked for NULL results from
 debug_ll_addr (e.g. when selected UART isn't valid). Fixed compile when
 either !CONFIG_DEBUG_LL or CONFIG_DEBUG_SEMIHOSTING.]
Signed-off-by: NStephen Warren <swarren@nvidia.com>
Signed-off-by: NOlof Johansson <olof@lixom.net>