Pull second set of arm64 updates from Catalin Marinas:

 - KASLR bug fixes: use callee-saved register, boot-time I-cache
   maintenance

 - inv_entry asm macro fix (EL0 check typo)

 - pr_notice("Virtual kernel memory layout...") splitting

 - Clean-ups: use p?d_set_huge consistently, allow preemption around
   copy_to_user_page, remove unused __local_flush_icache_all()

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: mm: allow preemption in copy_to_user_page
  arm64: consistently use p?d_set_huge
  arm64: kaslr: use callee saved register to preserve SCTLR across C call
  arm64: Split pr_notice("Virtual kernel memory layout...") into multiple pr_cont()
  arm64: drop unused __local_flush_icache_all()
  arm64: fix KASLR boot-time I-cache maintenance
  arm64/kernel: fix incorrect EL0 check in inv_entry macro

After commit 65da0a8e34a8 ("arm64: use non-global mappings for UEFI
runtime regions"), nobody use __local_flush_icache_all() anymore,
so drop it.

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

Instead of defining mark_rodata_ro() in each architecture, consolidate it.

Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Gross <agross@codeaurora.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Ashok Kumar <ashoks@broadcom.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Brown <david.brown@linaro.org>
Cc: David Hildenbrand <dahi@linux.vnet.ibm.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Emese Revfy <re.emese@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Helge Deller <deller@gmx.de>
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathias Krause <minipli@googlemail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Cc: PaX Team <pageexec@freemail.hu>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: kernel-hardening@lists.openwall.com
Cc: linux-arch <linux-arch@vger.kernel.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-parisc@vger.kernel.org
Link: http://lkml.kernel.org/r/1455748879-21872-2-git-send-email-keescook@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

In systems with three levels of cache(PoU at L1 and PoC at L3),
PoC cache flush instructions flushes L2 and L3 caches which could affect
performance.
For cache flushes for I and D coherency, PoU should suffice.
So changing all I and D coherency related cache flushes to PoU.

Introduced a new __clean_dcache_area_pou API for dcache flush till PoU
and provided a common macro for __flush_dcache_area and
__clean_dcache_area_pou.

Also, now in __sync_icache_dcache, icache invalidation for non-aliasing
VIPT icache is done only for that particular page instead of the earlier
__flush_icache_all.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ashok Kumar <ashoks@broadcom.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

There are a number of places where a single CPU is running with a
private page-table and we need to perform maintenance on the TLB and
I-cache in order to ensure correctness, but do not require the operation
to be broadcast to other CPUs.

This patch adds local variants of tlb_flush_all and __flush_icache_all
to support these use-cases and updates the callers respectively.
__local_flush_icache_all also implies an isb, since it is intended to be
used synchronously.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: David Daney <david.daney@cavium.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

The documented semantics of flush_cache_all are not possible to provide
for arm64 (short of flushing the entire physical address space by VA),
and there are currently no users; KVM uses VA maintenance exclusively,
cpu_reset is never called, and the only two users outside of arch code
cannot be built for arm64.

While cpu_soft_reset and related functions (which call flush_cache_all)
were thought to be useful for kexec, their current implementations only
serve to mask bugs. For correctness kexec will need to perform
maintenance by VA anyway to account for system caches, line migration,
and other subtleties of the cache architecture. As the extent of this
cache maintenance will be kexec-specific, it should probably live in the
kexec code.

This patch removes flush_cache_all, and related unused components,
preventing further abuse.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Geoff Levand <geoff@infradead.org>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@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>

Update handling of cacheflush syscall with changes made in arch/arm
counterpart:
 - return error to userspace when flushing syscall fails
 - split user cache-flushing into interruptible chunks
 - don't bother rounding to nearest vma

Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
[will: changed internal return value from -EINTR to 0 to match arch/arm/]
Signed-off-by: Will Deacon <will.deacon@arm.com>

In a similar fashion to other architecture, add the infrastructure
and Kconfig to enable DEBUG_SET_MODULE_RONX support. When
enabled, module ranges will be marked read-only/no-execute as
appropriate.

Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
[will: fixed off-by-one in module end check]
Signed-off-by: Will Deacon <will.deacon@arm.com>

The architecture specification states that both DSB and ISB are required
between page table modifications and subsequent memory accesses using the
corresponding virtual address. When TLB invalidation takes place, the
tlb_flush_* functions already have the necessary barriers. However, there are
other functions like create_mapping() for which this is not the case.

The patch adds the DSB+ISB instructions in the set_pte() function for
valid kernel mappings. The invalid pte case is handled by tlb_flush_*
and the user mappings in general have a corresponding update_mmu_cache()
call containing a DSB. Even when update_mmu_cache() isn't called, the
kernel can still cope with an unlikely spurious page fault by
re-executing the instruction.

In addition, the set_pmd, set_pud() functions gain an ISB for
architecture compliance when block mappings are created.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Reported-by: Leif Lindholm <leif.lindholm@linaro.org>
Acked-by: Steve Capper <steve.capper@linaro.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: <stable@vger.kernel.org>