Bring the linker script in line with the recent increase of
L1_CACHE_BYTES to 128. Replace the hardcoded value of 64 with the
symbolic constant.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
[catalin.marinas@arm.com: fix up RW_DATA_SECTION as well]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

A kernel built with DEBUG_RO_DATA && !CONFIG_DEBUG_ALIGN_RODATA doesn't
have .text aligned to a page boundary, though fixup_executable works at
page-granularity thanks to its use of create_mapping. If .text is not
page-aligned, the first page it exists in may be marked non-executable,
leading to failures when an attempt is made to execute code in said
page.

This patch upgrades ALIGN_DEBUG_RO and ALIGN_DEBUG_RO_MIN to force page
alignment for DEBUG_RO_DATA && !CONFIG_DEBUG_ALIGN_RODATA kernels,
ensuring that all sections with specific RWX permission requirements are
mapped with the correct permissions.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reported-by: Jeremy Linton <jeremy.linton@arm.com>
Reviewed-by: Laura Abbott <laura@labbott.name>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Suzuki Poulose <suzuki.poulose@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Fixes: da141706aea52c1a ("arm64: add better page protections to arm64")
Cc: <stable@vger.kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

Move the kernel pagetable (both swapper and idmap) definitions
from the generic asm/page.h to a new file, asm/kernel-pgtable.h.

This is mostly a cosmetic change, to clean up the asm/page.h to
get rid of the arch specific details which are not needed by the
generic code.

Also renames the symbols to prevent conflicts. e.g,
 	BLOCK_SHIFT => SWAPPER_BLOCK_SHIFT

Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

Commit ea8c2e112445 ("arm64: Extend the idmap to the whole kernel
image") changed the early page table code so that the entire kernel
Image is covered by the identity map. This allows functions that
need to enable or disable the MMU to reside anywhere in the kernel
Image.

However, this change has the unfortunate side effect that the Image
cannot cross a physical 512 MB alignment boundary anymore, since the
early page table code cannot deal with the Image crossing a /virtual/
512 MB alignment boundary.

So instead, reduce the ID map to a single page, that is populated by
the contents of the .idmap.text section. Only three functions reside
there at the moment: __enable_mmu(), cpu_resume_mmu() and cpu_reset().
If new code is introduced that needs to manipulate the MMU state, it
should be added to this section as well.

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

The HYP init bounce page is a runtime construct that ensures that the
HYP init code does not cross a page boundary. However, this is something
we can do perfectly well at build time, by aligning the code appropriately.

For arm64, we just align to 4 KB, and enforce that the code size is less
than 4 KB, regardless of the chosen page size.

For ARM, the whole code is less than 256 bytes, so we tweak the linker
script to align at a power of 2 upper bound of the code size

Note that this also fixes a benign off-by-one error in the original bounce
page code, where a bounce page would be allocated unnecessarily if the code
was exactly 1 page in size.

On ARM, it also fixes an issue with very large kernels reported by Arnd
Bergmann, where stub sections with linker emitted veneers could erroneously
trigger the size/alignment ASSERT() in the linker script.

Tested-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>

Add page protections for arm64 similar to those in arm.
This is for security reasons to prevent certain classes
of exploits. The current method:

- Map all memory as either RWX or RW. We round to the nearest
  section to avoid creating page tables before everything is mapped
- Once everything is mapped, if either end of the RWX section should
  not be X, we split the PMD and remap as necessary
- When initmem is to be freed, we change the permissions back to
  RW (using stop machine if necessary to flush the TLB)
- If CONFIG_DEBUG_RODATA is set, the read only sections are set
  read only.

Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Tested-by: Kees Cook <keescook@chromium.org>
Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

.exit.* sections may be subject to patching by the new alternatives
framework and so shouldn't be discarded at link-time. Without this patch,
such a section will result in the following linker error:

`.exit.text' referenced in section `.altinstructions' of
 drivers/built-in.o: defined in discarded section `.exit.text' of
drivers/built-in.o

Signed-off-by: Will Deacon <will.deacon@arm.com>

With a blatant copy of some x86 bits we introduce the alternative
runtime patching "framework" to arm64.
This is quite basic for now and we only provide the functions we need
at this time.
This is connected to the newly introduced feature bits.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

Change our PE/COFF header to use the minimum file alignment of
512 bytes (0x200), as mandated by the PE/COFF spec v8.3

Also update the linker script so that the Image file itself is also a
round multiple of FileAlignment.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Roy Franz <roy.franz@linaro.org>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>

This patch changes the __init_end address to a
page align address, so that free_initmem() can
free the whole .init section, because if the end
address is not page aligned, it will round down to
a page align address, then the tail unligned page
will not be freed.

Signed-off-by: wang <yalin.wang2010@gmail.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>