With 48-bit VA space, the 64K page configuration uses 3 levels instead
of 2 and PUD_SIZE != PMD_SIZE. Since with 64K pages we only cover
PMD_SIZE with the initial swapper_pg_dir populated in head.S, the
memblock current_limit needs to be set accordingly in map_mem() to avoid
allocating unmapped memory. The memblock current_limit is progressively
increased as more blocks are mapped.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Compiling with STRICT_MM_TYPECHECKS gives the following
arch/arm64/mm/ioremap.c: In function ‘early_ioremap_init’:
arch/arm64/mm/ioremap.c:152:2: warning: passing argument 3 of
‘pud_populate’ from incompatible pointer type
pud_populate(&init_mm, pud, bm_pmd);
The data types for bm_pmd and bm_pud are incorrectly set to pte_t.
This patch corrects these types.
Signed-off-by: Steve Capper <steve.capper@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
When the pgd size is smaller than PAGE_SIZE, pgd_alloc() uses kzalloc()
to save space. However, this is not always naturally aligned as required
by the architecture. This patch creates a kmem_cache for pgd allocations
with the correct alignment.
The current kernel configurations with 4K pages + 39-bit VA and 64K
pages + 42-bit VA use a full page for the pgd and are not affected. The
patch is required for 48-bit VA with 64K pages where the pgd is 512
bytes.
Reported-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Activate the RCU fast_gup for ARM64. We also need to force THP splits to
broadcast an IPI s.t. we block in the fast_gup page walker. As THP
splits are comparatively rare, this should not lead to a noticeable
performance degradation.
Some pre-requisite functions pud_write and pud_page are also added.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Steve Capper <steve.capper@linaro.org>
Tested-by: Dann Frazier <dann.frazier@canonical.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Christoffer Dall <christoffer.dall@linaro.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Neither CMA nor noncoherent allocations support atomic allocations.
Add a dedicated atomic pool to support this.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: David Riley <davidriley@chromium.org>
Cc: Olof Johansson <olof@lixom.net>
Cc: Ritesh Harjain <ritesh.harjani@gmail.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Thierry Reding <thierry.reding@gmail.com>
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>
- eBPF JIT compiler for arm64
- CPU suspend backend for PSCI (firmware interface) with standard idle
states defined in DT (generic idle driver to be merged via a different
tree)
- Support for CONFIG_DEBUG_SET_MODULE_RONX
- Support for unmapped cpu-release-addr (outside kernel linear mapping)
- set_arch_dma_coherent_ops() implemented and bus notifiers removed
- EFI_STUB improvements when base of DRAM is occupied
- Typos in KGDB macros
- Clean-up to (partially) allow kernel building with LLVM
- Other clean-ups (extern keyword, phys_addr_t usage)
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Catalin Marinas:
- eBPF JIT compiler for arm64
- CPU suspend backend for PSCI (firmware interface) with standard idle
states defined in DT (generic idle driver to be merged via a
different tree)
- Support for CONFIG_DEBUG_SET_MODULE_RONX
- Support for unmapped cpu-release-addr (outside kernel linear mapping)
- set_arch_dma_coherent_ops() implemented and bus notifiers removed
- EFI_STUB improvements when base of DRAM is occupied
- Typos in KGDB macros
- Clean-up to (partially) allow kernel building with LLVM
- Other clean-ups (extern keyword, phys_addr_t usage)
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (51 commits)
arm64: Remove unneeded extern keyword
ARM64: make of_device_ids const
arm64: Use phys_addr_t type for physical address
aarch64: filter $x from kallsyms
arm64: Use DMA_ERROR_CODE to denote failed allocation
arm64: Fix typos in KGDB macros
arm64: insn: Add return statements after BUG_ON()
arm64: debug: don't re-enable debug exceptions on return from el1_dbg
Revert "arm64: dmi: Add SMBIOS/DMI support"
arm64: Implement set_arch_dma_coherent_ops() to replace bus notifiers
of: amba: use of_dma_configure for AMBA devices
arm64: dmi: Add SMBIOS/DMI support
arm64: Correct ftrace calls to aarch64_insn_gen_branch_imm()
arm64:mm: initialize max_mapnr using function set_max_mapnr
setup: Move unmask of async interrupts after possible earlycon setup
arm64: LLVMLinux: Fix inline arm64 assembly for use with clang
arm64: pageattr: Correctly adjust unaligned start addresses
net: bpf: arm64: fix module memory leak when JIT image build fails
arm64: add PSCI CPU_SUSPEND based cpu_suspend support
arm64: kernel: introduce cpu_init_idle CPU operation
...
This patch extends the start and end address of initrd to be page aligned,
so that we can free all memory including the un-page aligned head or tail
page of initrd, if the start or end address of initrd are not page
aligned, the page can't be freed by free_initrd_mem() function.
Signed-off-by: Yalin Wang <yalin.wang@sonymobile.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Change the type of physical address from unsigned long to phys_addr_t,
make valid_phys_addr_range more readable.
Signed-off-by: Min-Hua Chen <orca.chen@gmail.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This patch replaces the static assignment of ~0 to dma_handle with
DMA_ERROR_CODE to be consistent with other platforms.
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Commit 6ecba8eb51 (arm64: Use bus notifiers to set per-device coherent
DMA ops) introduced bus notifiers to set the coherent dma ops based on
the 'dma-coherent' DT property. Since the generic of_dma_configure()
handles this property for platform and AMBA devices, replace the
notifiers with set_arch_dma_coherent_ops().
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Initializing max_mapnr using set_max_mapnr() helper function instead
of direct reference. Also not adding PHYS_PFN_OFFSET to max_pfn,
since it already contains it.
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Ganapatrao Kulkarni <ganapatrao.kulkarni@caviumnetworks.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Remove '#' from immediate parameter in AARCH64 inline assembly in mmu.
This code now works with both gcc and clang.
Signed-off-by: Mark Charlebois <charlebm@gmail.com>
Signed-off-by: Behan Webster <behanw@converseincode.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
The start address needs to be actually updated after it
is detected to be unaligned. Adjust it and the end address
properly.
Reported-by: Zi Shen Lim <zlim.lnx@gmail.com>
Reviewed-by: Zi Shen Lim <zlim.lnx@gmail.com>
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Commit 86c8b27a01:
"arm64: ignore DT memreserve entries when booting in UEFI mode
prevents early_init_fdt_scan_reserved_mem() from being called for
arm64 kernels booting via UEFI. This was done because the kernel
will use the UEFI memory map to determine reserved memory regions.
That approach has problems in that early_init_fdt_scan_reserved_mem()
also reserves the FDT itself and any node-specific reserved memory.
By chance of some kernel configs, the FDT may be overwritten before
it can be unflattened and the kernel will fail to boot. More subtle
problems will result if the FDT has node specific reserved memory
which is not really reserved.
This patch has the UEFI stub remove the memory reserve map entries
from the FDT as it does with the memory nodes. This allows
early_init_fdt_scan_reserved_mem() to be called unconditionally
so that the other needed reservations are made.
Signed-off-by: Mark Salter <msalter@redhat.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.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 current soft_restart() and setup_restart implementations incorrectly
assume that compiler will not spill/fill values to/from stack. However
this assumption seems to be wrong, revealed by the disassembly of the
currently existing code (v3.16) built with Linaro GCC 4.9-2014.05.
ffffffc000085224 <soft_restart>:
ffffffc000085224: a9be7bfd stp x29, x30, [sp,#-32]!
ffffffc000085228: 910003fd mov x29, sp
ffffffc00008522c: f9000fa0 str x0, [x29,#24]
ffffffc000085230: 94003d21 bl ffffffc0000946b4 <setup_mm_for_reboot>
ffffffc000085234: 94003b33 bl ffffffc000093f00 <flush_cache_all>
ffffffc000085238: 94003dfa bl ffffffc000094a20 <cpu_cache_off>
ffffffc00008523c: 94003b31 bl ffffffc000093f00 <flush_cache_all>
ffffffc000085240: b0003321 adrp x1, ffffffc0006ea000 <reset_devices>
ffffffc000085244: f9400fa0 ldr x0, [x29,#24] ----> spilled addr
ffffffc000085248: f942fc22 ldr x2, [x1,#1528] ----> global memstart_addr
ffffffc00008524c: f0000061 adrp x1, ffffffc000094000 <__inval_cache_range+0x40>
ffffffc000085250: 91290021 add x1, x1, #0xa40
ffffffc000085254: 8b010041 add x1, x2, x1
ffffffc000085258: d2c00802 mov x2, #0x4000000000 // #274877906944
ffffffc00008525c: 8b020021 add x1, x1, x2
ffffffc000085260: d63f0020 blr x1
...
Here the compiler generates memory accesses after the cache is disabled,
loading stale values for the spilled value and global variable. As we cannot
control when the compiler will access memory we must rewrite the
functions in assembly to stash values we need in registers prior to
disabling the cache, avoiding the use of memory.
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Arun Chandran <achandran@mvista.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
UEFI provides its own method for marking regions to reserve, via the
memory map which is also used to initialise memblock. So when using the
UEFI memory map, ignore any memreserve entries present in the DT.
Reported-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Changes include:
- Context tracking support (NO_HZ_FULL) which narrowly missed 3.16
- vDSO layout rework following Andy's work on x86
- TEXT_OFFSET fuzzing for bootloader testing
- /proc/cpuinfo tidy-up
- Preliminary work to support 48-bit virtual addresses, but this is
currently disabled until KVM has been ported to use it (the patches
do, however, bring some nice clean-up)
- Boot-time CPU sanity checks (especially useful on heterogenous
systems)
- Support for syscall auditing
- Support for CC_STACKPROTECTOR
- defconfig updates
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Will Deacon:
"Once again, Catalin's off on holiday and I'm looking after the arm64
tree. Please can you pull the following arm64 updates for 3.17?
Note that this branch also includes the new GICv3 driver (merged via a
stable tag from Jason's irqchip tree), since there is a fix for older
binutils on top.
Changes include:
- context tracking support (NO_HZ_FULL) which narrowly missed 3.16
- vDSO layout rework following Andy's work on x86
- TEXT_OFFSET fuzzing for bootloader testing
- /proc/cpuinfo tidy-up
- preliminary work to support 48-bit virtual addresses, but this is
currently disabled until KVM has been ported to use it (the patches
do, however, bring some nice clean-up)
- boot-time CPU sanity checks (especially useful on heterogenous
systems)
- support for syscall auditing
- support for CC_STACKPROTECTOR
- defconfig updates"
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (55 commits)
arm64: add newline to I-cache policy string
Revert "arm64: dmi: Add SMBIOS/DMI support"
arm64: fpsimd: fix a typo in fpsimd_save_partial_state ENDPROC
arm64: don't call break hooks for BRK exceptions from EL0
arm64: defconfig: enable devtmpfs mount option
arm64: vdso: fix build error when switching from LE to BE
arm64: defconfig: add virtio support for running as a kvm guest
arm64: gicv3: Allow GICv3 compilation with older binutils
arm64: fix soft lockup due to large tlb flush range
arm64/crypto: fix makefile rule for aes-glue-%.o
arm64: Do not invoke audit_syscall_* functions if !CONFIG_AUDIT_SYSCALL
arm64: Fix barriers used for page table modifications
arm64: Add support for 48-bit VA space with 64KB page configuration
arm64: asm/pgtable.h pmd/pud definitions clean-up
arm64: Determine the vmalloc/vmemmap space at build time based on VA_BITS
arm64: Clean up the initial page table creation in head.S
arm64: Remove asm/pgtable-*level-types.h files
arm64: Remove asm/pgtable-*level-hwdef.h files
arm64: Convert bool ARM64_x_LEVELS to int ARM64_PGTABLE_LEVELS
arm64: mm: Implement 4 levels of translation tables
...
Rather than guessing what the maximum vmmemap space should be, this
patch allows the calculation based on the VA_BITS and sizeof(struct
page). The vmalloc space extends to the beginning of the vmemmap space.
Since the virtual kernel memory layout now depends on the build
configuration, this patch removes the detailed description in
Documentation/arm64/memory.txt in favour of information printed during
kernel booting.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Jungseok Lee <jungseoklee85@gmail.com>
Rather than having several Kconfig options, define int
ARM64_PGTABLE_LEVELS which will be also useful in converting some of the
pgtable macros.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Jungseok Lee <jungseoklee85@gmail.com>
This patch implements 4 levels of translation tables since 3 levels
of page tables with 4KB pages cannot support 40-bit physical address
space described in [1] due to the following issue.
It is a restriction that kernel logical memory map with 4KB + 3 levels
(0xffffffc000000000-0xffffffffffffffff) cannot cover RAM region from
544GB to 1024GB in [1]. Specifically, ARM64 kernel fails to create
mapping for this region in map_mem function since __phys_to_virt for
this region reaches to address overflow.
If SoC design follows the document, [1], over 32GB RAM would be placed
from 544GB. Even 64GB system is supposed to use the region from 544GB
to 576GB for only 32GB RAM. Naturally, it would reach to enable 4 levels
of page tables to avoid hacking __virt_to_phys and __phys_to_virt.
However, it is recommended 4 levels of page table should be only enabled
if memory map is too sparse or there is about 512GB RAM.
References
----------
[1]: Principles of ARM Memory Maps, White Paper, Issue C
Signed-off-by: Jungseok Lee <jays.lee@samsung.com>
Reviewed-by: Sungjinn Chung <sungjinn.chung@samsung.com>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Steve Capper <steve.capper@linaro.org>
[catalin.marinas@arm.com: MEMBLOCK_INITIAL_LIMIT removed, same as PUD_SIZE]
[catalin.marinas@arm.com: early_ioremap_init() updated for 4 levels]
[catalin.marinas@arm.com: 48-bit VA depends on BROKEN until KVM is fixed]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Jungseok Lee <jungseoklee85@gmail.com>
The early_ioremap_init() function already handles fixmap pte
initialisation, so upgrade this to cover all of pud/pmd/pte and remove
one page from swapper_pg_dir.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Jungseok Lee <jungseoklee85@gmail.com>
ZONE_DMA is created to allow 32-bit only devices to access memory in the
absence of an IOMMU. On systems where the memory starts above 4GB, it is
expected that some devices have a DMA offset hardwired to be able to
access the bottom of the memory. Linux currently supports DT bindings
for the DMA offsets but they are not (easily) available early during
boot.
This patch tries to guess a DMA offset and assumes that ZONE_DMA
corresponds to the 32-bit mask above the start of DRAM.
Fixes: 2d5a5612bc (arm64: Limit the CMA buffer to 32-bit if ZONE_DMA)
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Reported-by: Mark Salter <msalter@redhat.com>
Tested-by: Mark Salter <msalter@redhat.com>
Tested-by: Anup Patel <anup.patel@linaro.org>
Currently we place swapper_pg_dir and idmap_pg_dir below the kernel
image, between PHYS_OFFSET and (PHYS_OFFSET + TEXT_OFFSET). However,
bootloaders may use portions of this memory below the kernel and we do
not parse the memory reservation list until after the MMU has been
enabled. As such we may clobber some memory a bootloader wishes to have
preserved.
To enable the use of all of this memory by bootloaders (when the
required memory reservations are communicated to the kernel) it is
necessary to move our initial page tables elsewhere. As we currently
have an effectively unbound requirement for memory at the end of the
kernel image for .bss, we can place the page tables here.
This patch moves the initial page table to the end of the kernel image,
after the BSS. As they do not consist of any initialised data they will
be stripped from the kernel Image as with the BSS. The BSS clearing
routine is updated to stop at __bss_stop rather than _end so as to not
clobber the page tables, and memory reservations made redundant by the
new organisation are removed.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Laura Abbott <lauraa@codeaurora.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
The __cpu_clear_user_page() and __cpu_copy_user_page() functions
are not currently exported. This prevents modules from using
clear_user_page() and copy_user_page().
Signed-off-by: Mark Salter <msalter@redhat.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
The __sync_icache_dcache routine will only flush the dcache for the
first page of a compound page, potentially leading to stale icache
data residing further on in a hugetlb page.
This patch addresses this issue by taking into consideration the
order of the page when flushing the dcache.
Reported-by: Mark Brown <broonie@linaro.org>
Tested-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Steve Capper <steve.capper@linaro.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: <stable@vger.kernel.org> # v3.11+
When the CMA buffer is allocated, it is too early to know whether
devices will require ZONE_DMA memory. This patch limits the CMA buffer
to (DMA_BIT_MASK(32) + 1) if CONFIG_ZONE_DMA is enabled.
In addition, it computes the dma_to_phys(DMA_BIT_MASK(32)) before the
increment (no current functional change).
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Strings library contributed to glibc but re-licensed under GPLv2)
- Optimised crypto algorithms making use of the ARMv8 crypto extensions
(together with kernel API for using FPSIMD instructions in interrupt
context)
- Ftrace support
- CPU topology parsing from DT
- ESR_EL1 (Exception Syndrome Register) exposed to user space signal
handlers for SIGSEGV/SIGBUS (useful to emulation tools like Qemu)
- 1GB section linear mapping if applicable
- Barriers usage clean-up
- Default pgprot clean-up
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux into next
Pull arm64 updates from Catalin Marinas:
- Optimised assembly string/memory routines (based on the AArch64
Cortex Strings library contributed to glibc but re-licensed under
GPLv2)
- Optimised crypto algorithms making use of the ARMv8 crypto extensions
(together with kernel API for using FPSIMD instructions in interrupt
context)
- Ftrace support
- CPU topology parsing from DT
- ESR_EL1 (Exception Syndrome Register) exposed to user space signal
handlers for SIGSEGV/SIGBUS (useful to emulation tools like Qemu)
- 1GB section linear mapping if applicable
- Barriers usage clean-up
- Default pgprot clean-up
Conflicts as per Catalin.
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (57 commits)
arm64: kernel: initialize broadcast hrtimer based clock event device
arm64: ftrace: Add system call tracepoint
arm64: ftrace: Add CALLER_ADDRx macros
arm64: ftrace: Add dynamic ftrace support
arm64: Add ftrace support
ftrace: Add arm64 support to recordmcount
arm64: Add 'notrace' attribute to unwind_frame() for ftrace
arm64: add __ASSEMBLY__ in asm/insn.h
arm64: Fix linker script entry point
arm64: lib: Implement optimized string length routines
arm64: lib: Implement optimized string compare routines
arm64: lib: Implement optimized memcmp routine
arm64: lib: Implement optimized memset routine
arm64: lib: Implement optimized memmove routine
arm64: lib: Implement optimized memcpy routine
arm64: defconfig: enable a few more common/useful options in defconfig
ftrace: Make CALLER_ADDRx macros more generic
arm64: Fix deadlock scenario with smp_send_stop()
arm64: Fix machine_shutdown() definition
arm64: Support arch_irq_work_raise() via self IPIs
...
Pull ARM64 EFI update from Peter Anvin:
"By agreement with the ARM64 EFI maintainers, we have agreed to make
-tip the upstream for all EFI patches. That is why this patchset
comes from me :)
This patchset enables EFI stub support for ARM64, like we already have
on x86"
* 'arm64-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
arm64: efi: only attempt efi map setup if booting via EFI
efi/arm64: ignore dtb= when UEFI SecureBoot is enabled
doc: arm64: add description of EFI stub support
arm64: efi: add EFI stub
doc: arm: add UEFI support documentation
arm64: add EFI runtime services
efi: Add shared FDT related functions for ARM/ARM64
arm64: Add function to create identity mappings
efi: add helper function to get UEFI params from FDT
doc: efi-stub.txt updates for ARM
lib: add fdt_empty_tree.c
Currently hugepage migration is available for all archs which support
pmd-level hugepage, but testing is done only for x86_64 and there're
bugs for other archs. So to avoid breaking such archs, this patch
limits the availability strictly to x86_64 until developers of other
archs get interested in enabling this feature.
Simply disabling hugepage migration on non-x86_64 archs is not enough to
fix the reported problem where sys_move_pages() hits the BUG_ON() in
follow_page(FOLL_GET), so let's fix this by checking if hugepage
migration is supported in vma_migratable().
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reported-by: Michael Ellerman <mpe@ellerman.id.au>
Tested-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: David Miller <davem@davemloft.net>
Cc: <stable@vger.kernel.org> [3.12+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- Another round of clean-up of FDT related code in architecture code.
This removes knowledge of internal FDT details from most architectures
except powerpc.
- Conversion of kernel's custom FDT parsing code to use libfdt.
- DT based initialization for generic serial earlycon. The introduction
of generic serial earlycon support went in thru tty tree.
- Improve the platform device naming for DT probed devices to ensure
unique naming and use parent names instead of a global index.
- Fix a race condition in of_update_property.
- Unify the various linker section OF match tables and fix several
function prototype errors.
- Update platform_get_irq_byname to work in deferred probe cases.
- 2 binding doc updates
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Merge tag 'devicetree-for-3.16' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux into next
Pull DeviceTree updates from Rob Herring:
- Another round of clean-up of FDT related code in architecture code.
This removes knowledge of internal FDT details from most
architectures except powerpc.
- Conversion of kernel's custom FDT parsing code to use libfdt.
- DT based initialization for generic serial earlycon. The
introduction of generic serial earlycon support went in through the
tty tree.
- Improve the platform device naming for DT probed devices to ensure
unique naming and use parent names instead of a global index.
- Fix a race condition in of_update_property.
- Unify the various linker section OF match tables and fix several
function prototype errors.
- Update platform_get_irq_byname to work in deferred probe cases.
- 2 binding doc updates
* tag 'devicetree-for-3.16' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (58 commits)
of: handle NULL node in next_child iterators
of/irq: provide more wrappers for !CONFIG_OF
devicetree: bindings: Document micrel vendor prefix
dt: bindings: dwc2: fix required value for the phy-names property
of_pci_irq: kill useless variable in of_irq_parse_pci()
of/irq: do irq resolution in platform_get_irq_byname()
of: Add a testcase for of_find_node_by_path()
of: Make of_find_node_by_path() handle /aliases
of: Create unlocked version of for_each_child_of_node()
lib: add glibc style strchrnul() variant
of: Handle memory@0 node on PPC32 only
pci/of: Remove dead code
of: fix race between search and remove in of_update_property()
of: Use NULL for pointers
of: Stop naming platform_device using dcr address
of: Ensure unique names without sacrificing determinism
tty/serial: pl011: add DT based earlycon support
of/fdt: add FDT serial scanning for earlycon
of/fdt: add FDT address translation support
serial: earlycon: add DT support
...
The following happens when trying to run a kvm guest on a kernel
configured for 64k pages. This doesn't happen with 4k pages:
BUG: failure at include/linux/mm.h:297/put_page_testzero()!
Kernel panic - not syncing: BUG!
CPU: 2 PID: 4228 Comm: qemu-system-aar Tainted: GF 3.13.0-0.rc7.31.sa2.k32v1.aarch64.debug #1
Call trace:
[<fffffe0000096034>] dump_backtrace+0x0/0x16c
[<fffffe00000961b4>] show_stack+0x14/0x1c
[<fffffe000066e648>] dump_stack+0x84/0xb0
[<fffffe0000668678>] panic+0xf4/0x220
[<fffffe000018ec78>] free_reserved_area+0x0/0x110
[<fffffe000018edd8>] free_pages+0x50/0x88
[<fffffe00000a759c>] kvm_free_stage2_pgd+0x30/0x40
[<fffffe00000a5354>] kvm_arch_destroy_vm+0x18/0x44
[<fffffe00000a1854>] kvm_put_kvm+0xf0/0x184
[<fffffe00000a1938>] kvm_vm_release+0x10/0x1c
[<fffffe00001edc1c>] __fput+0xb0/0x288
[<fffffe00001ede4c>] ____fput+0xc/0x14
[<fffffe00000d5a2c>] task_work_run+0xa8/0x11c
[<fffffe0000095c14>] do_notify_resume+0x54/0x58
In arch/arm/kvm/mmu.c:unmap_range(), we end up doing an extra put_page()
on the stage2 pgd which leads to the BUG in put_page_testzero(). This
happens because a pud_huge() test in unmap_range() returns true when it
should always be false with 2-level pages tables used by 64k pages.
This patch removes support for huge puds if 2-level pagetables are
being used.
Signed-off-by: Mark Salter <msalter@redhat.com>
[catalin.marinas@arm.com: removed #ifndef around PUD_SIZE check]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: <stable@vger.kernel.org> # v3.11+
This reverts commit bc07c2c6e9.
While the aim is increased security for --x memory maps, it does not
protect against kernel level reads. Until SECCOMP is implemented for
arm64, revert this patch to avoid giving a false idea of execute-only
mappings.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
In order to ensure ordering and completion of inner-shareable maintenance
instructions (cache and TLB) on AArch64, we can use the -ish suffix to
the dmb and dsb instructions respectively.
This patch updates our low-level cache and tlb maintenance routines to
use the inner-shareable barrier variants where appropriate.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
The tlb maintainence functions: __cpu_flush_user_tlb_range and
__cpu_flush_kern_tlb_range do not take into consideration the page
granule when looping through the address range, and repeatedly flush
tlb entries for the same page when operating with 64K pages.
This patch re-works the logic s.t. we instead advance the loop by
1 << (PAGE_SHIFT - 12), so avoid repeating ourselves.
Also the routines have been converted from assembler to static inline
functions to aid with legibility and potential compiler optimisations.
The isb() has been removed from flush_tlb_kernel_range(.) as it is
only needed when changing the execute permission of a mapping. If one
needs to set an area of the kernel as execute/non-execute an isb()
must be inserted after the call to flush_tlb_kernel_range.
Cc: Laura Abbott <lauraa@codeaurora.org>
Signed-off-by: Steve Capper <steve.capper@linaro.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
We have the capability to map 1GB level 1 blocks when using a 4K
granule.
This patch adjusts the create_mapping logic s.t. when mapping physical
memory on boot, we attempt to use a 1GB block if both the VA and PA
start and end are 1GB aligned. This both reduces the levels of lookup
required to resolve a kernel logical address, as well as reduces TLB
pressure on cores that support 1GB TLB entries.
Signed-off-by: Steve Capper <steve.capper@linaro.org>
Tested-by: Jungseok Lee <jays.lee@samsung.com>
[catalin.marinas@arm.com: s/prot_sect_kernel/PROT_SECT_NORMAL_EXEC/]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
The primary aim of this patchset is to remove the pgprot_default and
prot_sect_default global variables and rely strictly on predefined
values. The original goal was to be able to run SMP kernels on UP
hardware by not setting the Shareability bit. However, it is unlikely to
see UP ARMv8 hardware and even if we do, the Shareability bit is no
longer assumed to disable cacheable accesses.
A side effect is that the device mappings now have the Shareability
attribute set. The hardware, however, should ignore it since Device
accesses are always Outer Shareable.
Following the removal of the two global variables, there is some PROT_*
macro reshuffling and cleanup, including the __PAGE_* macros (replaced
by PAGE_*).
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
The ARMv8 architecture allows execute-only user permissions by clearing
the PTE_UXN and PTE_USER bits. The kernel, however, can still access
such page, so execute-only page permission does not protect against
read(2)/write(2) etc. accesses. Systems requiring such protection must
implement/enable features like SECCOMP.
This patch changes the arm64 __P100 and __S100 protection_map[] macros
to the new __PAGE_EXECONLY attributes. A side effect is that
pte_valid_user() no longer triggers for __PAGE_EXECONLY since PTE_USER
isn't set. To work around this, the check is done on the PTE_NG bit via
the pte_valid_ng() macro. VM_READ is also checked now for page faults.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
For AArch32, bit 11 (WnR) of the FSR/ESR register is set when the fault
was caused by a write access and applications like Qemu rely on such
information being provided in sigcontext. This patch introduces the
ESR_EL1 tracking for the arm64 kernel faults and sets bit 11 accordingly
in compat sigcontext.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Recently, the default DMA ops have been changed to non-coherent for
alignment with 32-bit ARM platforms (and DT files). This patch adds bus
notifiers to be able to set the coherent DMA ops (with no cache
maintenance) for devices explicitly marked as coherent via the
"dma-coherent" DT property.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Currently arm64 dma_ops is by default made coherent which makes it
opposite in default policy from arm.
Make default dma_ops to be noncoherent (same as arm), as currently there
aren't any dma-capable drivers which assumes coherent ops
Signed-off-by: Ritesh Harjani <ritesh.harjani@gmail.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Fix for the arm64 kern_addr_valid() function to recognize
virtual addresses in the kernel logical memory map. The
function fails as written because it does not check whether
the addresses in that region are mapped at the pmd level to
2MB or 512MB pages, continues the page table walk to the
pte level, and issues a garbage value to pfn_valid().
Tested on 4K-page and 64K-page kernels.
Signed-off-by: Dave Anderson <anderson@redhat.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
At boot time, before switching to a virtual UEFI memory map, firmware
expects UEFI memory and IO regions to be identity mapped whenever
kernel makes runtime services calls. The existing early boot code
creates an identity map of kernel text/data but this is not sufficient
for UEFI. This patch adds a create_id_mapping() function which reuses
the core code of the existing create_mapping().
Signed-off-by: Mark Salter <msalter@redhat.com>
[ Fixed error message formatting (%pa). ]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Move the /memreserve/ processing and dtb memory reservations into
early_init_fdt_scan_reserved_mem. This converts arm, arm64, and powerpc
as they are the only users of early_init_fdt_scan_reserved_mem.
memblock_reserve is safe to call on the same region twice, so the
reservation check for the dtb in powerpc 32-bit reservations is safe to
remove.
Signed-off-by: Rob Herring <robh@kernel.org>
Tested-by: Michal Simek <michal.simek@xilinx.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Tested-by: Grant Likely <grant.likely@linaro.org>
Tested-by: Stephen Chivers <schivers@csc.com>
- Additional cache flushing during boot (needed in the presence of
external caches or under virtualisation)
- DMA range invalidation fix for non cache line aligned buffers
- Build failure fix with !COMPAT
- Kconfig update for STRICT_DEVMEM
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull second set of arm64 updates from Catalin Marinas:
"A second pull request for this merging window, mainly with fixes and
docs clarification:
- Documentation clarification on CPU topology and booting
requirements
- Additional cache flushing during boot (needed in the presence of
external caches or under virtualisation)
- DMA range invalidation fix for non cache line aligned buffers
- Build failure fix with !COMPAT
- Kconfig update for STRICT_DEVMEM"
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: Fix DMA range invalidation for cache line unaligned buffers
arm64: Add missing Kconfig for CONFIG_STRICT_DEVMEM
arm64: fix !CONFIG_COMPAT build failures
Revert "arm64: virt: ensure visibility of __boot_cpu_mode"
arm64: Relax the kernel cache requirements for boot
arm64: Update the TCR_EL1 translation granule definitions for 16K pages
ARM: topology: Make it clear that all CPUs need to be described
If the buffer needing cache invalidation for inbound DMA does start or
end on a cache line aligned address, we need to use the non-destructive
clean&invalidate operation. This issue was introduced by commit
7363590d2c (arm64: Implement coherent DMA API based on swiotlb).
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Reported-by: Jon Medhurst (Tixy) <tixy@linaro.org>
Add support for early IO or memory mappings which are needed before the
normal ioremap() is usable. This also adds fixmap support for permanent
fixed mappings such as that used by the earlyprintk device register
region.
Signed-off-by: Mark Salter <msalter@redhat.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Borislav Petkov <borislav.petkov@amd.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Presently, paging_init() calls init_mem_pgprot() to initialize pgprot
values used by macros such as PAGE_KERNEL, PAGE_KERNEL_EXEC, etc.
The new fixmap and early_ioremap support also needs to use these macros
before paging_init() is called. This patch moves the init_mem_pgprot()
call out of paging_init() and into setup_arch() so that pgprot_default
gets initialized in time for fixmap and early_ioremap.
Signed-off-by: Mark Salter <msalter@redhat.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Borislav Petkov <borislav.petkov@amd.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>