Currently arm64's FIXADDR_{START,SIZE} definitions only cover the
runtime fixmap slots (and not the boot-time fixmap slots), but the code
for creating the fixmap assumes that these definitions cover the entire
fixmap range. This means that the ptdump boundaries are reported in a
misleading way, missing the VA region of the runtime slots. In theory
this could also cause the fixmap creation to go wrong if the boot-time
fixmap slots end up spilling into a separate PMD entry, though luckily
this is not currently the case in any configuration.
While it seems like we could extend FIXADDR_{START,SIZE} to cover the
entire fixmap area, core code relies upon these *only* covering the
runtime slots. For example, fix_to_virt() and virt_to_fix() try to
reject manipulation of the boot-time slots based upon
FIXADDR_{START,SIZE}, while __fix_to_virt() and __virt_to_fix() can
handle any fixmap slot.
This patch follows the lead of x86 in commit:
55f49fcb87 ("x86/mm: Fix overlap of i386 CPU_ENTRY_AREA with FIX_BTMAP")
... and add new FIXADDR_TOT_{START,SIZE} definitions which cover the
entire fixmap area, using these for the fixmap creation and ptdump code.
As the boot-time fixmap slots are now rejected by fix_to_virt(),
the early_fixmap_init() code is changed to consistently use
__fix_to_virt(), as it already does in a few cases.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Will Deacon <will@kernel.org>
Reviewed-by: Ryan Roberts <ryan.roberts@arm.com>
Link: https://lore.kernel.org/r/20230406152759.4164229-2-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
Commit 91fc957c9b ("arm64/bpf: don't allocate BPF JIT programs in module
memory") restricts BPF JIT program allocation to a 128MB region to ensure
BPF programs are still in branching range of each other. However this
restriction should not apply to the aarch64 JIT, since BPF_JMP | BPF_CALL
are implemented as a 64-bit move into a register and then a BLR instruction -
which has the effect of being able to call anything without proximity
limitation.
The practical reason to relax this restriction on JIT memory is that 128MB of
JIT memory can be quickly exhausted, especially where PAGE_SIZE is 64KB - one
page is needed per program. In cases where seccomp filters are applied to
multiple VMs on VM launch - such filters are classic BPF but converted to
BPF - this can severely limit the number of VMs that can be launched. In a
world where we support BPF JIT always on, turning off the JIT isn't always an
option either.
Fixes: 91fc957c9b ("arm64/bpf: don't allocate BPF JIT programs in module memory")
Suggested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Russell King <russell.king@oracle.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Alan Maguire <alan.maguire@oracle.com>
Link: https://lore.kernel.org/bpf/1636131046-5982-2-git-send-email-alan.maguire@oracle.com
Currently arm64 allows a choice of FLATMEM, SPARSEMEM and
SPARSEMEM_VMEMMAP. However, only the latter is tested regularly. FLATMEM
does not seem to boot in certain configurations (guest under KVM with
Qemu as a VMM). Since the reduction of the SECTION_SIZE_BITS to 27 (4K
pages) or 29 (64K page), there's little argument against the memory
wasted by the mem_map array with SPARSEMEM.
Make SPARSEMEM_VMEMMAP the only available option, non-selectable, and
remove the corresponding #ifdefs under arch/arm64/.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Link: https://lore.kernel.org/r/20210420093559.23168-1-catalin.marinas@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
They are not needed after booting, so mark them as __init to move them
to the .init section.
Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Link: https://lore.kernel.org/r/20210330135449.4dcffd7f@xhacker.debian
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
The current /sys/kernel/debug/kernel_page_tables does not display the
*Linear Mapping start* marker on arm64, which I think should be paired
with the *Linear Mapping end* marker.
Since *Linear Mapping start* is the first marker, use initialise 'level'
to -1 in order to display it.
Signed-off-by: Hailong Liu <liu.hailong6@zte.com.cn>
Link: https://lore.kernel.org/r/20210202150749.10104-1-liuhailongg6@163.com
Signed-off-by: Will Deacon <will@kernel.org>
Add userspace support for the Memory Tagging Extension introduced by
Armv8.5.
(Catalin Marinas and others)
* for-next/mte: (30 commits)
arm64: mte: Fix typo in memory tagging ABI documentation
arm64: mte: Add Memory Tagging Extension documentation
arm64: mte: Kconfig entry
arm64: mte: Save tags when hibernating
arm64: mte: Enable swap of tagged pages
mm: Add arch hooks for saving/restoring tags
fs: Handle intra-page faults in copy_mount_options()
arm64: mte: ptrace: Add NT_ARM_TAGGED_ADDR_CTRL regset
arm64: mte: ptrace: Add PTRACE_{PEEK,POKE}MTETAGS support
arm64: mte: Allow {set,get}_tagged_addr_ctrl() on non-current tasks
arm64: mte: Restore the GCR_EL1 register after a suspend
arm64: mte: Allow user control of the generated random tags via prctl()
arm64: mte: Allow user control of the tag check mode via prctl()
mm: Allow arm64 mmap(PROT_MTE) on RAM-based files
arm64: mte: Validate the PROT_MTE request via arch_validate_flags()
mm: Introduce arch_validate_flags()
arm64: mte: Add PROT_MTE support to mmap() and mprotect()
mm: Introduce arch_calc_vm_flag_bits()
arm64: mte: Tags-aware aware memcmp_pages() implementation
arm64: Avoid unnecessary clear_user_page() indirection
...
Kernel virtual region [BPF_JIT_REGION_START..BPF_JIT_REGION_END] is missing
from address_markers[], hence relevant page table entries are not displayed
with /sys/kernel/debug/kernel_page_tables. This adds those missing markers.
While here, also rename arch/arm64/mm/dump.c which sounds bit ambiguous, as
arch/arm64/mm/ptdump.c instead.
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Steven Price <steven.price@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Link: https://lore.kernel.org/r/1599208259-11191-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
