kernel/linux.git/arch/arm64/include/asm/memory.h, branch v5.10.259

arm64: kasan: fix page_alloc tagging with DEBUG_VIRTUAL

2021-03-17T16:06:27+00:00

commit 86c83365ab76e4b43cedd3ce07a07d32a4dc79ba upstream. When CONFIG_DEBUG_VIRTUAL is enabled, the default page_to_virt() macro implementation from include/linux/mm.h is used. That definition doesn't account for KASAN tags, which leads to no tags on page_alloc allocations. Provide an arm64-specific definition for page_to_virt() when CONFIG_DEBUG_VIRTUAL is enabled that takes care of KASAN tags. Fixes: 2813b9c02962 ("kasan, mm, arm64: tag non slab memory allocated via pagealloc") Cc: Signed-off-by: Andrey Konovalov Reviewed-by: Catalin Marinas Link: https://lore.kernel.org/r/4b55b35202706223d3118230701c6a59749d9b72.1615219501.git.andreyknvl@google.com Signed-off-by: Will Deacon Signed-off-by: Greg Kroah-Hartman

arm64: Do not pass tagged addresses to __is_lm_address()

2021-02-07T14:37:13+00:00

commit 91cb2c8b072e00632adf463b78b44f123d46a0fa upstream. Commit 519ea6f1c82f ("arm64: Fix kernel address detection of __is_lm_address()") fixed the incorrect validation of addresses below PAGE_OFFSET. However, it no longer allowed tagged addresses to be passed to virt_addr_valid(). Fix this by explicitly resetting the pointer tag prior to invoking __is_lm_address(). This is consistent with the __lm_to_phys() macro. Fixes: 519ea6f1c82f ("arm64: Fix kernel address detection of __is_lm_address()") Signed-off-by: Catalin Marinas Acked-by: Ard Biesheuvel Cc: # 5.4.x Cc: Will Deacon Cc: Vincenzo Frascino Cc: Mark Rutland Link: https://lore.kernel.org/r/20210201190634.22942-2-catalin.marinas@arm.com Signed-off-by: Greg Kroah-Hartman

arm64: Fix kernel address detection of __is_lm_address()

2021-02-07T14:37:12+00:00

commit 519ea6f1c82fcdc9842908155ae379de47818778 upstream. Currently, the __is_lm_address() check just masks out the top 12 bits of the address, but if they are 0, it still yields a true result. This has as a side effect that virt_addr_valid() returns true even for invalid virtual addresses (e.g. 0x0). Fix the detection checking that it's actually a kernel address starting at PAGE_OFFSET. Fixes: 68dd8ef32162 ("arm64: memory: Fix virt_addr_valid() using __is_lm_address()") Cc: # 5.4.x Cc: Will Deacon Suggested-by: Catalin Marinas Reviewed-by: Catalin Marinas Acked-by: Mark Rutland Signed-off-by: Vincenzo Frascino Link: https://lore.kernel.org/r/20210126134056.45747-1-vincenzo.frascino@arm.com Signed-off-by: Catalin Marinas Signed-off-by: Greg Kroah-Hartman

arm64: mm: use single quantity to represent the PA to VA translation

2020-10-15T10:14:57+00:00

On arm64, the global variable memstart_addr represents the physical address of PAGE_OFFSET, and so physical to virtual translations or vice versa used to come down to simple additions or subtractions involving the values of PAGE_OFFSET and memstart_addr. When support for 52-bit virtual addressing was introduced, we had to deal with PAGE_OFFSET potentially being outside of the region that can be covered by the virtual range (as the 52-bit VA capable build needs to be able to run on systems that are only 48-bit VA capable), and for this reason, another translation was introduced, and recorded in the global variable physvirt_offset. However, if we go back to the original definition of memstart_addr, i.e., the physical address of PAGE_OFFSET, it turns out that there is no need for two separate translations: instead, we can simply subtract the size of the unaddressable VA space from memstart_addr to make the available physical memory appear in the 48-bit addressable VA region. This simplifies things, but also fixes a bug on KASLR builds, which may update memstart_addr later on in arm64_memblock_init(), but fails to update vmemmap and physvirt_offset accordingly. Fixes: 5383cc6efed1 ("arm64: mm: Introduce vabits_actual") Signed-off-by: Ard Biesheuvel Reviewed-by: Steve Capper Link: https://lore.kernel.org/r/20201008153602.9467-2-ardb@kernel.org Signed-off-by: Will Deacon

Merge branch 'for-next/mte' into for-next/core

2020-10-02T11:16:11+00:00

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 ...

arm64: get rid of TEXT_OFFSET

2020-09-07T14:00:52+00:00

TEXT_OFFSET serves no purpose, and for this reason, it was redefined as 0x0 in the v5.8 timeframe. Since this does not appear to have caused any issues that require us to revisit that decision, let's get rid of the macro entirely, along with any references to it. Signed-off-by: Ard Biesheuvel Link: https://lore.kernel.org/r/20200825135440.11288-1-ardb@kernel.org Signed-off-by: Will Deacon

arm64: mte: Add PROT_MTE support to mmap() and mprotect()

2020-09-04T11:46:07+00:00

To enable tagging on a memory range, the user must explicitly opt in via a new PROT_MTE flag passed to mmap() or mprotect(). Since this is a new memory type in the AttrIndx field of a pte, simplify the or'ing of these bits over the protection_map[] attributes by making MT_NORMAL index 0. There are two conditions for arch_vm_get_page_prot() to return the MT_NORMAL_TAGGED memory type: (1) the user requested it via PROT_MTE, registered as VM_MTE in the vm_flags, and (2) the vma supports MTE, decided during the mmap() call (only) and registered as VM_MTE_ALLOWED. arch_calc_vm_prot_bits() is responsible for registering the user request as VM_MTE. The newly introduced arch_calc_vm_flag_bits() sets VM_MTE_ALLOWED if the mapping is MAP_ANONYMOUS. An MTE-capable filesystem (RAM-based) may be able to set VM_MTE_ALLOWED during its mmap() file ops call. In addition, update VM_DATA_DEFAULT_FLAGS to allow mprotect(PROT_MTE) on stack or brk area. The Linux mmap() syscall currently ignores unknown PROT_* flags. In the presence of MTE, an mmap(PROT_MTE) on a file which does not support MTE will not report an error and the memory will not be mapped as Normal Tagged. For consistency, mprotect(PROT_MTE) will not report an error either if the memory range does not support MTE. Two subsequent patches in the series will propose tightening of this behaviour. Co-developed-by: Vincenzo Frascino Signed-off-by: Vincenzo Frascino Signed-off-by: Catalin Marinas Cc: Will Deacon

arm64: mte: Use Normal Tagged attributes for the linear map

2020-09-03T16:26:31+00:00

Once user space is given access to tagged memory, the kernel must be able to clear/save/restore tags visible to the user. This is done via the linear mapping, therefore map it as such. The new MT_NORMAL_TAGGED index for MAIR_EL1 is initially mapped as Normal memory and later changed to Normal Tagged via the cpufeature infrastructure. From a mismatched attribute aliases perspective, the Tagged memory is considered a permission and it won't lead to undefined behaviour. Signed-off-by: Catalin Marinas Cc: Will Deacon Cc: Suzuki K Poulose

Merge branch 'for-next/read-barrier-depends' into for-next/core

2020-07-31T17:09:57+00:00

* for-next/read-barrier-depends: : Allow architectures to override __READ_ONCE() arm64: Reduce the number of header files pulled into vmlinux.lds.S compiler.h: Move compiletime_assert() macros into compiler_types.h checkpatch: Remove checks relating to [smp_]read_barrier_depends() include/linux: Remove smp_read_barrier_depends() from comments tools/memory-model: Remove smp_read_barrier_depends() from informal doc Documentation/barriers/kokr: Remove references to [smp_]read_barrier_depends() Documentation/barriers: Remove references to [smp_]read_barrier_depends() locking/barriers: Remove definitions for [smp_]read_barrier_depends() alpha: Replace smp_read_barrier_depends() usage with smp_[r]mb() vhost: Remove redundant use of read_barrier_depends() barrier asm/rwonce: Don't pull into 'asm-generic/rwonce.h' asm/rwonce: Remove smp_read_barrier_depends() invocation alpha: Override READ_ONCE() with barriered implementation asm/rwonce: Allow __READ_ONCE to be overridden by the architecture compiler.h: Split {READ,WRITE}_ONCE definitions out into rwonce.h tools: bpf: Use local copy of headers including uapi/linux/filter.h

arm64: Reduce the number of header files pulled into vmlinux.lds.S

2020-07-21T09:50:37+00:00

Although vmlinux.lds.S smells like an assembly file and is compiled with __ASSEMBLY__ defined, it's actually just fed to the preprocessor to create our linker script. This means that any assembly macros defined by headers that it includes will result in a helpful link error: | aarch64-linux-gnu-ld:./arch/arm64/kernel/vmlinux.lds:1: syntax error In preparation for an arm64-private asm/rwonce.h implementation, which will end up pulling assembly macros into linux/compiler.h, reduce the number of headers we include directly and transitively in vmlinux.lds.S Acked-by: Peter Zijlstra (Intel) Signed-off-by: Will Deacon