This fixes a Keystone 2 regression discovered as a side effect of
defining an passing the physical start/end sections of the kernel
to the MMU remapping code.
As the Keystone applies an offset to all physical addresses,
including those identified and patches by phys2virt, we fail to
account for this offset in the kernel_sec_start and kernel_sec_end
variables.
Further these offsets can extend into the 64bit range on LPAE
systems such as the Keystone 2.
Fix it like this:
- Extend kernel_sec_start and kernel_sec_end to be 64bit
- Add the offset also to kernel_sec_start and kernel_sec_end
As passing kernel_sec_start and kernel_sec_end as 64bit invariably
incurs BE8 endianness issues I have attempted to dry-code around
these.
Tested on the Vexpress QEMU model both with and without LPAE
enabled.
Fixes: 6e121df14c ("ARM: 9090/1: Map the lowmem and kernel separately")
Reported-by: Nishanth Menon <nmenon@kernel.org>
Suggested-by: Russell King <rmk+kernel@armlinux.org.uk>
Tested-by: Grygorii Strashko <grygorii.strashko@ti.com>
Tested-by: Nishanth Menon <nmenon@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
The kernel test robot reported an interesting bug:
A debug print was using %08x with kernel_sec_start and kernel_sec_end
being phys_addr_t which can be either u32 or u64 (possibly more).
Actually these should just be declared as u32 to begin with: they are
declared as such in the assembly in head.S and the kernel definitely
boots in a 32 bit physical address space. Redeclare the kernel_sec_start
and kernel_sec_end to rid the bug.
Reported-by: kernel test robot <lkp@intel.com>
Fixes: 6e121df14c ("ARM: 9090/1: Map the lowmem and kernel separately")
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
When we are mapping the initial sections in head.S we
know very well where the start and end of the kernel image
in physical memory is placed. Later on it gets hard
to determine this.
Save the information into two variables named
kernel_sec_start and kernel_sec_end for convenience
for later work involving the physical start and end
of the kernel. These variables are section-aligned
corresponding to the early section mappings set up
in head.S.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
We want to be able to compile the kernel into an address different
from PAGE_OFFSET (start of lowmem) + TEXT_OFFSET, so start to pry
apart the address of where the kernel is located from the address
where the lowmem is located by defining and using KERNEL_OFFSET in
a few key places.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Now that we have reduced the number of registers that we need to
preserve when calling v7_invalidate_l1 from the boot code, we can use
scratch registers to preserve the remaining ones, and get rid of the
mini stack entirely. This works around any issues regarding cache
behavior in relation to the uncached accesses to this memory, which is
hard to get right in the general case (i.e., both bare metal and under
virtualization)
While at it, switch v7_invalidate_l1 to using ip as a scratch register
instead of r4. This makes the function AAPCS compliant, and removes the
need to stash r4 in ip across the call.
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
The ARM kernel's linear map starts at PAGE_OFFSET, which maps to a
physical address (PHYS_OFFSET) that is platform specific, and is
discovered at boot. Since we don't want to slow down translations
between physical and virtual addresses by keeping the offset in a
variable in memory, we implement this by patching the code performing
the translation, and putting the offset between PAGE_OFFSET and the
start of physical RAM directly into the instruction opcodes.
As we only patch up to 8 bits of offset, yielding 4 GiB >> 8 == 16 MiB
of granularity, we have to round up PHYS_OFFSET to the next multiple if
the start of physical RAM is not a multiple of 16 MiB. This wastes some
physical RAM, since the memory that was skipped will now live below
PAGE_OFFSET, making it inaccessible to the kernel.
We can improve this by changing the patchable sequences and the patching
logic to carry more bits of offset: 11 bits gives us 4 GiB >> 11 == 2 MiB
of granularity, and so we will never waste more than that amount by
rounding up the physical start of DRAM to the next multiple of 2 MiB.
(Note that 2 MiB granularity guarantees that the linear mapping can be
created efficiently, whereas less than 2 MiB may result in the linear
mapping needing another level of page tables)
This helps Zhen Lei's scenario, where the start of DRAM is known to be
occupied. It also helps EFI boot, which relies on the firmware's page
allocator to allocate space for the decompressed kernel as low as
possible. And if the KASLR patches ever land for 32-bit, it will give
us 3 more bits of randomization of the placement of the kernel inside
the linear region.
For the ARM code path, it simply comes down to using two add/sub
instructions instead of one for the carryless version, and patching
each of them with the correct immediate depending on the rotation
field. For the LPAE calculation, which has to deal with a carry, it
patches the MOVW instruction with up to 12 bits of offset (but we only
need 11 bits anyway)
For the Thumb2 code path, patching more than 11 bits of displacement
would be somewhat cumbersome, but the 11 bits we need fit nicely into
the second word of the u16[2] opcode, so we simply update the immediate
assignment and the left shift to create an addend of the right magnitude.
Suggested-by: Zhen Lei <thunder.leizhen@huawei.com>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
In preparation for reducing the phys-to-virt minimum relative alignment
from 16 MiB to 2 MiB, switch to patchable sequences involving MOVW
instructions that can more easily be manipulated to carry a 12-bit
immediate. Note that the non-LPAE ARM sequence is not updated: MOVW
may not be supported on non-LPAE platforms, and the sequence itself
can be updated more easily to apply the 12 bits of displacement.
For Thumb2, which has many more versions of opcodes, switch to a sequence
that can be patched by the same patching code for both versions. Note
that the Thumb2 opcodes for MOVW and MVN are unambiguous, and have no
rotation bits in their immediate fields, so there is no need to use
placeholder constants in the asm blocks.
While at it, drop the 'volatile' qualifiers from the asm blocks: the
code does not have any side effects that are invisible to the compiler,
so it is free to omit these sequences if the outputs are not used.
Suggested-by: Russell King <linux@armlinux.org.uk>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Free up a register in the p2v patching code by switching to relative
references, which don't require keeping the phys-to-virt displacement
live in a register.
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
We always pass the same value for 'type' so pull it into the __pv_stub
macro itself.
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Commit
149a3ffe62b9dbc3 ("9012/1: move device tree mapping out of linear region")
created a permanent, read-only section mapping of the device tree blob
provided by the firmware, and added a set of macros to get the base and
size of the virtually mapped FDT based on the physical address. However,
while the mapping code uses the SECTION_SIZE macro correctly, the macros
use PMD_SIZE instead, which means something entirely different on ARM when
using short descriptors, and is therefore not the right quantity to use
here. So replace PMD_SIZE with SECTION_SIZE. While at it, change the names
of the macro and its parameter to clarify that it returns the virtual
address of the start of the FDT, based on the physical address in memory.
Tested-by: Joel Stanley <joel@jms.id.au>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Define KASAN_SHADOW_OFFSET,KASAN_SHADOW_START and KASAN_SHADOW_END for
the Arm kernel address sanitizer. We are "stealing" lowmem (the 4GB
addressable by a 32bit architecture) out of the virtual address
space to use as shadow memory for KASan as follows:
+----+ 0xffffffff
| |
| | |-> Static kernel image (vmlinux) BSS and page table
| |/
+----+ PAGE_OFFSET
| |
| | |-> Loadable kernel modules virtual address space area
| |/
+----+ MODULES_VADDR = KASAN_SHADOW_END
| |
| | |-> The shadow area of kernel virtual address.
| |/
+----+-> TASK_SIZE (start of kernel space) = KASAN_SHADOW_START the
| | shadow address of MODULES_VADDR
| | |
| | |
| | |-> The user space area in lowmem. The kernel address
| | | sanitizer do not use this space, nor does it map it.
| | |
| | |
| | |
| | |
| |/
------ 0
0 .. TASK_SIZE is the memory that can be used by shared
userspace/kernelspace. It us used for userspace processes and for
passing parameters and memory buffers in system calls etc. We do not
need to shadow this area.
KASAN_SHADOW_START:
This value begins with the MODULE_VADDR's shadow address. It is the
start of kernel virtual space. Since we have modules to load, we need
to cover also that area with shadow memory so we can find memory
bugs in modules.
KASAN_SHADOW_END
This value is the 0x100000000's shadow address: the mapping that would
be after the end of the kernel memory at 0xffffffff. It is the end of
kernel address sanitizer shadow area. It is also the start of the
module area.
KASAN_SHADOW_OFFSET:
This value is used to map an address to the corresponding shadow
address by the following formula:
shadow_addr = (address >> 3) + KASAN_SHADOW_OFFSET;
As you would expect, >> 3 is equal to dividing by 8, meaning each
byte in the shadow memory covers 8 bytes of kernel memory, so one
bit shadow memory per byte of kernel memory is used.
The KASAN_SHADOW_OFFSET is provided in a Kconfig option depending
on the VMSPLIT layout of the system: the kernel and userspace can
split up lowmem in different ways according to needs, so we calculate
the shadow offset depending on this.
When kasan is enabled, the definition of TASK_SIZE is not an 8-bit
rotated constant, so we need to modify the TASK_SIZE access code in the
*.s file.
The kernel and modules may use different amounts of memory,
according to the VMSPLIT configuration, which in turn
determines the PAGE_OFFSET.
We use the following KASAN_SHADOW_OFFSETs depending on how the
virtual memory is split up:
- 0x1f000000 if we have 1G userspace / 3G kernelspace split:
- The kernel address space is 3G (0xc0000000)
- PAGE_OFFSET is then set to 0x40000000 so the kernel static
image (vmlinux) uses addresses 0x40000000 .. 0xffffffff
- On top of that we have the MODULES_VADDR which under
the worst case (using ARM instructions) is
PAGE_OFFSET - 16M (0x01000000) = 0x3f000000
so the modules use addresses 0x3f000000 .. 0x3fffffff
- So the addresses 0x3f000000 .. 0xffffffff need to be
covered with shadow memory. That is 0xc1000000 bytes
of memory.
- 1/8 of that is needed for its shadow memory, so
0x18200000 bytes of shadow memory is needed. We
"steal" that from the remaining lowmem.
- The KASAN_SHADOW_START becomes 0x26e00000, to
KASAN_SHADOW_END at 0x3effffff.
- Now we can calculate the KASAN_SHADOW_OFFSET for any
kernel address as 0x3f000000 needs to map to the first
byte of shadow memory and 0xffffffff needs to map to
the last byte of shadow memory. Since:
SHADOW_ADDR = (address >> 3) + KASAN_SHADOW_OFFSET
0x26e00000 = (0x3f000000 >> 3) + KASAN_SHADOW_OFFSET
KASAN_SHADOW_OFFSET = 0x26e00000 - (0x3f000000 >> 3)
KASAN_SHADOW_OFFSET = 0x26e00000 - 0x07e00000
KASAN_SHADOW_OFFSET = 0x1f000000
- 0x5f000000 if we have 2G userspace / 2G kernelspace split:
- The kernel space is 2G (0x80000000)
- PAGE_OFFSET is set to 0x80000000 so the kernel static
image uses 0x80000000 .. 0xffffffff.
- On top of that we have the MODULES_VADDR which under
the worst case (using ARM instructions) is
PAGE_OFFSET - 16M (0x01000000) = 0x7f000000
so the modules use addresses 0x7f000000 .. 0x7fffffff
- So the addresses 0x7f000000 .. 0xffffffff need to be
covered with shadow memory. That is 0x81000000 bytes
of memory.
- 1/8 of that is needed for its shadow memory, so
0x10200000 bytes of shadow memory is needed. We
"steal" that from the remaining lowmem.
- The KASAN_SHADOW_START becomes 0x6ee00000, to
KASAN_SHADOW_END at 0x7effffff.
- Now we can calculate the KASAN_SHADOW_OFFSET for any
kernel address as 0x7f000000 needs to map to the first
byte of shadow memory and 0xffffffff needs to map to
the last byte of shadow memory. Since:
SHADOW_ADDR = (address >> 3) + KASAN_SHADOW_OFFSET
0x6ee00000 = (0x7f000000 >> 3) + KASAN_SHADOW_OFFSET
KASAN_SHADOW_OFFSET = 0x6ee00000 - (0x7f000000 >> 3)
KASAN_SHADOW_OFFSET = 0x6ee00000 - 0x0fe00000
KASAN_SHADOW_OFFSET = 0x5f000000
- 0x9f000000 if we have 3G userspace / 1G kernelspace split,
and this is the default split for ARM:
- The kernel address space is 1GB (0x40000000)
- PAGE_OFFSET is set to 0xc0000000 so the kernel static
image uses 0xc0000000 .. 0xffffffff.
- On top of that we have the MODULES_VADDR which under
the worst case (using ARM instructions) is
PAGE_OFFSET - 16M (0x01000000) = 0xbf000000
so the modules use addresses 0xbf000000 .. 0xbfffffff
- So the addresses 0xbf000000 .. 0xffffffff need to be
covered with shadow memory. That is 0x41000000 bytes
of memory.
- 1/8 of that is needed for its shadow memory, so
0x08200000 bytes of shadow memory is needed. We
"steal" that from the remaining lowmem.
- The KASAN_SHADOW_START becomes 0xb6e00000, to
KASAN_SHADOW_END at 0xbfffffff.
- Now we can calculate the KASAN_SHADOW_OFFSET for any
kernel address as 0xbf000000 needs to map to the first
byte of shadow memory and 0xffffffff needs to map to
the last byte of shadow memory. Since:
SHADOW_ADDR = (address >> 3) + KASAN_SHADOW_OFFSET
0xb6e00000 = (0xbf000000 >> 3) + KASAN_SHADOW_OFFSET
KASAN_SHADOW_OFFSET = 0xb6e00000 - (0xbf000000 >> 3)
KASAN_SHADOW_OFFSET = 0xb6e00000 - 0x17e00000
KASAN_SHADOW_OFFSET = 0x9f000000
- 0x8f000000 if we have 3G userspace / 1G kernelspace with
full 1 GB low memory (VMSPLIT_3G_OPT):
- The kernel address space is 1GB (0x40000000)
- PAGE_OFFSET is set to 0xb0000000 so the kernel static
image uses 0xb0000000 .. 0xffffffff.
- On top of that we have the MODULES_VADDR which under
the worst case (using ARM instructions) is
PAGE_OFFSET - 16M (0x01000000) = 0xaf000000
so the modules use addresses 0xaf000000 .. 0xaffffff
- So the addresses 0xaf000000 .. 0xffffffff need to be
covered with shadow memory. That is 0x51000000 bytes
of memory.
- 1/8 of that is needed for its shadow memory, so
0x0a200000 bytes of shadow memory is needed. We
"steal" that from the remaining lowmem.
- The KASAN_SHADOW_START becomes 0xa4e00000, to
KASAN_SHADOW_END at 0xaeffffff.
- Now we can calculate the KASAN_SHADOW_OFFSET for any
kernel address as 0xaf000000 needs to map to the first
byte of shadow memory and 0xffffffff needs to map to
the last byte of shadow memory. Since:
SHADOW_ADDR = (address >> 3) + KASAN_SHADOW_OFFSET
0xa4e00000 = (0xaf000000 >> 3) + KASAN_SHADOW_OFFSET
KASAN_SHADOW_OFFSET = 0xa4e00000 - (0xaf000000 >> 3)
KASAN_SHADOW_OFFSET = 0xa4e00000 - 0x15e00000
KASAN_SHADOW_OFFSET = 0x8f000000
- The default value of 0xffffffff for KASAN_SHADOW_OFFSET
is an error value. We should always match one of the
above shadow offsets.
When we do this, TASK_SIZE will sometimes get a bit odd values
that will not fit into immediate mov assembly instructions.
To account for this, we need to rewrite some assembly using
TASK_SIZE like this:
- mov r1, #TASK_SIZE
+ ldr r1, =TASK_SIZE
or
- cmp r4, #TASK_SIZE
+ ldr r0, =TASK_SIZE
+ cmp r4, r0
this is done to avoid the immediate #TASK_SIZE that need to
fit into a limited number of bits.
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: kasan-dev@googlegroups.com
Cc: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Ard Biesheuvel <ardb@kernel.org> # QEMU/KVM/mach-virt/LPAE/8G
Tested-by: Florian Fainelli <f.fainelli@gmail.com> # Brahma SoCs
Tested-by: Ahmad Fatoum <a.fatoum@pengutronix.de> # i.MX6Q
Reported-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Abbott Liu <liuwenliang@huawei.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
On ARM, setting up the linear region is tricky, given the constraints
around placement and alignment of the memblocks, and how the kernel
itself as well as the DT are placed in physical memory.
Let's simplify matters a bit, by moving the device tree mapping to the
top of the address space, right between the end of the vmalloc region
and the start of the the fixmap region, and create a read-only mapping
for it that is independent of the size of the linear region, and how it
is organized.
Since this region was formerly used as a guard region, which will now be
populated fully on LPAE builds by this read-only mapping (which will
still be able to function as a guard region for stray writes), bump the
start of the [underutilized] fixmap region by 512 KB as well, to ensure
that there is always a proper guard region here. Doing so still leaves
ample room for the fixmap space, even with NR_CPUS set to its maximum
value of 32.
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Based on 2 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation #
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 4122 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ARM, ARM64 and UniCore32 duplicate the definition of UL():
#define UL(x) _AC(x, UL)
This is not actually arch-specific, so it will be useful to move it to a
common header. Currently, we only have the uapi variant for
linux/const.h, so I am creating include/linux/const.h.
I also added _UL(), _ULL() and ULL() because _AC() is mostly used in
the form either _AC(..., UL) or _AC(..., ULL). I expect they will be
replaced in follow-up cleanups. The underscore-prefixed ones should
be used for exported headers.
Link: http://lkml.kernel.org/r/1519301715-31798-4-git-send-email-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Guan Xuetao <gxt@mprc.pku.edu.cn>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Russell King <rmk+kernel@armlinux.org.uk>
Cc: David Howells <dhowells@redhat.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
With switch to dynamic exception base address setting, VBAR/Hivecs
set only for boot CPU, but secondaries stay unaware of that. That
might lead to weird effects when trying up to bring up secondaries.
Fixes: ad475117d2 ("ARM: 8649/2: nommu: remove Hivecs configuration is asm")
Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Acked-by: afzal mohammed <afzal.mohd.ma@gmail.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
VECTORS_BASE displays the exception base address. Now on no-MMU as
the exception base address is dynamically estimated, define
VECTORS_BASE to the variable holding it.
As it is the case, limit VECTORS_BASE constant definition to MMU.
Suggested-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: afzal mohammed <afzal.mohd.ma@gmail.com>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
For MMU configurations, VECTORS_BASE is always 0xffff0000, a macro
definition will suffice.
For no-MMU, exception base address is dynamically determined in
subsequent patches. To preserve bisectability, now make the
macro applicable for no-MMU scenario too.
Thanks to 0-DAY kernel test infrastructure that found the
bisectability issue. This macro will be restricted to MMU case upon
dynamically determining exception base address for no-MMU.
Once exception address is handled dynamically for no-MMU,
VECTORS_BASE can be removed from Kconfig.
Signed-off-by: afzal mohammed <afzal.mohd.ma@gmail.com>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
x86 has an option: CONFIG_DEBUG_VIRTUAL to do additional checks on
virt_to_phys calls. The goal is to catch users who are calling
virt_to_phys on non-linear addresses immediately. This includes caller
using __virt_to_phys() on image addresses instead of __pa_symbol(). This
is a generally useful debug feature to spot bad code (particulary in
drivers).
Acked-by: Russell King <rmk+kernel@armlinux.org.uk>
Acked-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
In preparation for adding CONFIG_DEBUG_VIRTUAL support, define a set of
common constants: KERNEL_START and KERNEL_END which abstract
CONFIG_XIP_KERNEL vs. !CONFIG_XIP_KERNEL. Update the code where
relevant.
Acked-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The last ad-hoc __phys_to_virt definition was removed in commit fd0053c9
("ARM: realview: remove sparsemem hack"). Therefore we can remove the
unneeded definitions and unduplicate the virt_to_pfn macro from
asm/memory.h.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Provide a helper to indicate whether we need to perform special handling
for boot identity mapping aliases or not.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Reviewed-by: Pratyush Anand <panand@redhat.com>
For kexec, we need more functionality from the IDMAP system. We need to
be able to convert physical addresses to their identity mappped versions
as well as virtual addresses.
Convert the existing arch_virt_to_idmap() to deal with physical
addresses instead.
Acked-by: Santosh Shilimkar <ssantosh@kernel.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
All drivers that are relevant for rpc or footbridge have stopped
using virt_to_bus a while ago, so we can remove it and avoid some
harmless randconfig warnings for drivers that we do not care about:
drivers/atm/zatm.c: In function 'poll_rx':
drivers/atm/zatm.c:401:18: warning: 'bus_to_virt' is deprecated [-Wdeprecated-declarations]
skb = ((struct rx_buffer_head *) bus_to_virt(here[2]))->skb;
FWIW, the remaining drivers using this are:
ATM: firestream, zatm, ambassador, horizon
ISDN: hisax/netjet
V4L: STA2X11, zoran
Net: Appletalk LTPC, Tulip DE4x5, Toshiba IrDA
WAN: comtrol sv11, cosa, lanmedia, sealevel
SCSI: DPT_I2O, buslogic
VME: CA91C142
My best guess is that all of the above are so hopelessly obsolete that
we are best off removing all of them form the kernel, but that can be
done another time.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The physical-relative calculation between the XIP text and data sections
introduced by the previous patch was far from obvious. Let's simplify it
by turning it into a macro which takes the two (virtual) addresses.
This allows us to arrange the calculation in a more obvious manner - we
can make it two sub-expressions which calculate the physical address for
each symbol, and then takes the difference of those physical addresses.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
When XIP_KERNEL is enabled, the virt to phys address translation for RAM
is not the same as the virt to phys address translation for .text.
The only way to know where physical RAM is located is to use
PLAT_PHYS_OFFSET.
The MACRO will be useful for other places where there is a similar problem.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Chris Brandt <chris.brandt@renesas.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Make virt_to_idmap() return an unsigned long rather than phys_addr_t.
Returning phys_addr_t here makes no sense, because the definition of
virt_to_idmap() is that it shall return a physical address which maps
identically with the virtual address. Since virtual addresses are
limited to 32-bit, identity mapped physical addresses are as well.
Almost all users already had an implicit narrowing cast to unsigned long
so let's make this official and part of this interface.
Tested-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
16MB alignment for ioremap mappings was added by commit a069c896d0 ("[ARM]
3705/1: add supersection support to ioremap()") in order to support supersection
mappings. But __arm_ioremap_pfn_caller uses section and supersection mappings
only in !SMP && !LPAE case. There is no need for such big alignment if either
SMP or LPAE is enabled.
After this change, ioremap will use default maximum alignment of 128 pages.
Link: https://lkml.kernel.org/g/1419328813-2211-1-git-send-email-d.safonov@partner.samsung.com
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Cc: James Bottomley <JBottomley@parallels.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Arnd Bergmann <arnd.bergmann@linaro.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dmitry Safonov <d.safonov@partner.samsung.com>
Signed-off-by: Sergey Dyasly <s.dyasly@samsung.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Three architectures already define these, and we'll need them genericly
soon.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Fengguang Wu reports that building ARM with !MMU results in the
following build error:
arch/arm/kernel/built-in.o: In function `__soft_restart':
>> :(.text+0x1624): undefined reference to `arch_virt_to_idmap'
Fix this by adding an appropriate IS_ENABLED(CONFIG_MMU) into the
__virt_to_idmap() inline function.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch fixes pfn_to_kaddr() to use phys_addr_t. Without this,
this macro is broken on LPAE systems. For physical addresses above
first 4GB result of shifting pfn with PAGE_SHIFT may be truncated.
Signed-off-by: Vitaly Andrianov <vitalya@ti.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Santosh Shilimkar <ssantosh@kernel.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Re-engineer the LPAE TTBR setup code. Rather than passing some shifted
address in order to fit in a CPU register, pass either a full physical
address (in the case of r4, r5 for TTBR0) or a PFN (for TTBR1).
This removes the ARCH_PGD_SHIFT hack, and the last dangerous user of
cpu_set_ttbr() in the secondary CPU startup code path (which was there
to re-set TTBR1 to the appropriate high physical address space on
Keystone2.)
Tested-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Include the generic I/O header file so that duplicate implementations
can be removed. This will also help to establish consistency across more
architectures regarding which accessors they support.
Signed-off-by: Thierry Reding <treding@nvidia.com>
The platforms selecting NEED_MACH_MEMORY_H defined the start address of
their physical memory in the respective <mach/memory.h>. With
ARM_PATCH_PHYS_VIRT=y (which is quite common today) this is useless
though because the definition isn't used but determined dynamically.
So remove the definitions from all <mach/memory.h> and provide the
Kconfig symbol PHYS_OFFSET with the respective defaults in case
ARM_PATCH_PHYS_VIRT isn't enabled.
This allows to drop the dependency of PHYS_OFFSET on !NEED_MACH_MEMORY_H
which prevents compiling an integrator nommu-kernel.
(CONFIG_PAGE_OFFSET which has "default PHYS_OFFSET if !MMU" expanded to
"0x" because CONFIG_PHYS_OFFSET doesn't exist as INTEGRATOR selects
NEED_MACH_MEMORY_H.)
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
With TASK_SIZE set to the maximal RAM address booting in some XIP
configurations fails (e.g. on efm32 DK3750). The problem is that
strncpy_from_user et al. check for the address not being above TASK_SIZE
(since 8c56cc8be5 (ARM: 7449/1: use generic strnlen_user and
strncpy_from_user functions)) and this makes booting fail if the XIP
flash is above the RAM address space.
This change is in line with blackfin, frv and m68k which also use
0xffffffff for TASK_SIZE with !MMU.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
It looks like the static mapping area for DMA was replaced by dynamic
allocation into the vmalloc area by commit e9da6e9905 but the
information in Documentation/arm/memory.txt was not removed accordingly.
CONSISTENT_END in arch/arm/include/asm/memory.h has no more users and
can be removed as well.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
virt_to_page() is incredibly inefficient when virt-to-phys patching is
enabled. This is because we end up with this calculation:
page = &mem_map[asm virt_to_phys(addr) >> 12 - __pv_phys_offset >> 12]
in assembly. The asm virt_to_phys() is equivalent this this operation:
addr - PAGE_OFFSET + __pv_phys_offset
and we can see that because this is assembly, the compiler has no chance
to optimise some of that away. This should reduce down to:
page = &mem_map[(addr - PAGE_OFFSET) >> 12]
for the common cases. Permit the compiler to make this optimisation by
giving it more of the information it needs - do this by providing a
virt_to_pfn() macro.
Another issue which makes this more complex is that __pv_phys_offset is
a 64-bit type on all platforms. This is needlessly wasteful - if we
store the physical offset as a PFN, we can save a lot of work having
to deal with 64-bit values, which sometimes ends up producing incredibly
horrid code:
a4c: e3009000 movw r9, #0
a4c: R_ARM_MOVW_ABS_NC __pv_phys_offset
a50: e3409000 movt r9, #0 ; r9 = &__pv_phys_offset
a50: R_ARM_MOVT_ABS __pv_phys_offset
a54: e3002000 movw r2, #0
a54: R_ARM_MOVW_ABS_NC __pv_phys_offset
a58: e3402000 movt r2, #0 ; r2 = &__pv_phys_offset
a58: R_ARM_MOVT_ABS __pv_phys_offset
a5c: e5999004 ldr r9, [r9, #4] ; r9 = high word of __pv_phys_offset
a60: e3001000 movw r1, #0
a60: R_ARM_MOVW_ABS_NC mem_map
a64: e592c000 ldr ip, [r2] ; ip = low word of __pv_phys_offset
Reviewed-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
With noMMU, CONFIG_PAGE_OFFSET was not being set correctly. As there's
no MMU, PAGE_OFFSET should be equal to PHYS_OFFSET in all cases. This
commit makes that explicit.
Since we do this, we don't need to mess around in asm/memory.h with
ifdefs to sort this out, so let's get rid of that, and there's no point
offering the "Memory split" option for noMMU as that's meaningless
there.
Fixes: b9b32bf70f ("ARM: use linker magic for vectors and vector stubs")
Cc: <stable@vger.kernel.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The definition of virt_addr_valid is that virt_addr_valid should
return true if and only if virt_to_page returns a valid pointer.
The current definition of virt_addr_valid only checks against the
virtual address range. There's no guarantee that just because a
virtual address falls bewteen PAGE_OFFSET and high_memory the
associated physical memory has a valid backing struct page. Follow
the example of other architectures and convert to pfn_valid to
verify that the virtual address is actually valid. The check for
an address between PAGE_OFFSET and high_memory is still necessary
as vmalloc/highmem addresses are not valid with virt_to_page.
Cc: Will Deacon <will.deacon@arm.com>
Cc: Nicolas Pitre <nico@linaro.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Jason Gunthorpe reports a build failure when ARM_PATCH_PHYS_VIRT is
not defined:
In file included from arch/arm/include/asm/page.h:163:0,
from include/linux/mm_types.h:16,
from include/linux/sched.h:24,
from arch/arm/kernel/asm-offsets.c:13:
arch/arm/include/asm/memory.h: In function '__virt_to_phys':
arch/arm/include/asm/memory.h:244:40: error: 'PHYS_OFFSET' undeclared (first use in this function)
arch/arm/include/asm/memory.h:244:40: note: each undeclared identifier is reported only once for each function it appears in
arch/arm/include/asm/memory.h: In function '__phys_to_virt':
arch/arm/include/asm/memory.h:249:13: error: 'PHYS_OFFSET' undeclared (first use in this function)
Fixes: ca5a45c06c ("ARM: mm: use phys_addr_t appropriately in p2v and v2p conversions")
Tested-By: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Make sure that inline assembler that expects 'r' operand
receives 32 bit value.
Before this fix in case of CONFIG_ARCH_PHYS_ADDR_T_64BIT and
CONFIG_ARM_PATCH_PHYS_VIRT __phys_to_virt function passed 64 bit
value to __pv_stub inline assembler where 'r' operand is
expected. Compiler behavior in such case is not well specified.
It worked in little endian case, but in big endian case
incorrect code was generated, where compiler confused which
part of 64 bit value it needed to modify. For example BE
snippet looked like this:
N:0x80904E08 : MOV r2,#0
N:0x80904E0C : SUB r2,r2,#0x81000000
when LE similar code looked like this
N:0x808FCE2C : MOV r2,r0
N:0x808FCE30 : SUB r2,r2,#0xc0, 8 ; #0xc0000000
Note 'r0' register is va that have to be translated into phys
To avoid this situation use explicit cast to 'unsigned long',
which explicitly discard upper part of phys address and convert
value to 32 bit. Also add comment so such cast will not be
removed in the future.
Signed-off-by: Victor Kamensky <victor.kamensky@linaro.org>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Olof Johansson reported:
In file included from arch/arm/include/asm/page.h:163:0,
from include/linux/mm_types.h:16,
from include/linux/sched.h:24,
from arch/arm/kernel/asm-offsets.c:13:
arch/arm/include/asm/memory.h: In function '__virt_to_idmap':
arch/arm/include/asm/memory.h:300:6: error: 'arch_virt_to_idmap' undeclared (first use in this function)
caused by arch_virt_to_idmap being placed inside a different
preprocessor conditional to its user. Move it along side its user.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The current phys_to_virt patching mechanism works only for 32 bit
physical addresses and this patch extends the idea for 64bit physical
addresses.
The 64bit v2p patching mechanism patches the higher 8 bits of physical
address with a constant using 'mov' instruction and lower 32bits are patched
using 'add'. While this is correct, in those platforms where the lowmem addressable
physical memory spawns across 4GB boundary, a carry bit can be produced as a
result of addition of lower 32bits. This has to be taken in to account and added
in to the upper. The patched __pv_offset and va are added in lower 32bits, where
__pv_offset can be in two's complement form when PA_START < VA_START and that can
result in a false carry bit.
e.g
1) PA = 0x80000000; VA = 0xC0000000
__pv_offset = PA - VA = 0xC0000000 (2's complement)
2) PA = 0x2 80000000; VA = 0xC000000
__pv_offset = PA - VA = 0x1 C0000000
So adding __pv_offset + VA should never result in a true overflow for (1).
So in order to differentiate between a true carry, a __pv_offset is extended
to 64bit and the upper 32bits will have 0xffffffff if __pv_offset is
2's complement. So 'mvn #0' is inserted instead of 'mov' while patching
for the same reason. Since mov, add, sub instruction are to patched
with different constants inside the same stub, the rotation field
of the opcode is using to differentiate between them.
So the above examples for v2p translation becomes for VA=0xC0000000,
1) PA[63:32] = 0xffffffff
PA[31:0] = VA + 0xC0000000 --> results in a carry
PA[63:32] = PA[63:32] + carry
PA[63:0] = 0x0 80000000
2) PA[63:32] = 0x1
PA[31:0] = VA + 0xC0000000 --> results in a carry
PA[63:32] = PA[63:32] + carry
PA[63:0] = 0x2 80000000
The above ideas were suggested by Nicolas Pitre <nico@linaro.org> as
part of the review of first and second versions of the subject patch.
There is no corresponding change on the phys_to_virt() side, because
computations on the upper 32-bits would be discarded anyway.
Cc: Russell King <linux@arm.linux.org.uk>
Reviewed-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Sricharan R <r.sricharan@ti.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
On some PAE systems (e.g. TI Keystone), memory is above the
32-bit addressable limit, and the interconnect provides an
aliased view of parts of physical memory in the 32-bit addressable
space. This alias is strictly for boot time usage, and is not
otherwise usable because of coherency limitations. On such systems,
the idmap mechanism needs to take this aliased mapping into account.
This patch introduces virt_to_idmap() and a arch function pointer which
can be populated by platform which needs it. Also populate necessary
idmap spots with now available virt_to_idmap(). Avoided #ifdef approach
to be compatible with multi-platform builds.
Most architecture won't touch it and in that case virt_to_idmap()
fall-back to existing virt_to_phys() macro.
Cc: Russell King <linux@arm.linux.org.uk>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Fix remainder types used when converting back and forth between
physical and virtual addresses.
Cc: Russell King <linux@arm.linux.org.uk>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
VALID_PAGE() has been removed from kernel long time ago,
so fix the comment.
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Nicolas Pitre <nico@linaro.org>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: Giancarlo Asnaghi <giancarlo.asnaghi@st.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
On LPAE machines, PHYS_OFFSET evaluates to a phys_addr_t and this type is
inherited by the PHYS_PFN_OFFSET definition as well. Consequently, the kernel
build emits warnings of the form:
init/main.c: In function 'start_kernel':
init/main.c:588:7: warning: format '%lx' expects argument of type 'long unsigned int', but argument 2 has type 'phys_addr_t' [-Wformat]
This patch fixes this warning by pinning down the PFN type to unsigned long.
Signed-off-by: Cyril Chemparathy <cyril@ti.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: Subash Patel <subash.rp@samsung.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
