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2022-07-01arm64: hugetlb: Restore TLB invalidation for BBM on contiguous ptesWill Deacon1-9/+21
Commit fb396bb459c1 ("arm64/hugetlb: Drop TLB flush from get_clear_flush()") removed TLB invalidation from get_clear_flush() [now get_clear_contig()] on the basis that the core TLB invalidation code is aware of hugetlb mappings backed by contiguous page-table entries and will cover the correct virtual address range. However, this change also resulted in the TLB invalidation being removed from the "break" step in the break-before-make (BBM) sequence used internally by huge_ptep_set_{access_flags,wrprotect}(), therefore making the BBM sequence unsafe irrespective of later invalidation. Although the architecture is desperately unclear about how exactly contiguous ptes should be updated in a live page-table, restore TLB invalidation to our BBM sequence under the assumption that BBM is the right thing to be doing in the first place. Fixes: fb396bb459c1 ("arm64/hugetlb: Drop TLB flush from get_clear_flush()") Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Steve Capper <steve.capper@arm.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Marc Zyngier <maz@kernel.org> Signed-off-by: Will Deacon <will@kernel.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Link: https://lore.kernel.org/r/20220629095349.25748-1-will@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-06-17arm64: mm: Don't invalidate FROM_DEVICE buffers at start of DMA transferWill Deacon1-2/+0
Invalidating the buffer memory in arch_sync_dma_for_device() for FROM_DEVICE transfers When using the streaming DMA API to map a buffer prior to inbound non-coherent DMA (i.e. DMA_FROM_DEVICE), we invalidate any dirty CPU cachelines so that they will not be written back during the transfer and corrupt the buffer contents written by the DMA. This, however, poses two potential problems: (1) If the DMA transfer does not write to every byte in the buffer, then the unwritten bytes will contain stale data once the transfer has completed. (2) If the buffer has a virtual alias in userspace, then stale data may be visible via this alias during the period between performing the cache invalidation and the DMA writes landing in memory. Address both of these issues by cleaning (aka writing-back) the dirty lines in arch_sync_dma_for_device(DMA_FROM_DEVICE) instead of discarding them using invalidation. Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Robin Murphy <robin.murphy@arm.com> Cc: Russell King <linux@armlinux.org.uk> Cc: <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20220606152150.GA31568@willie-the-truck Signed-off-by: Will Deacon <will@kernel.org> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20220610151228.4562-2-will@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-06-06arm/xen: Introduce xen_setup_dma_ops()Oleksandr Tyshchenko1-5/+2
This patch introduces new helper and places it in new header. The helper's purpose is to assign any Xen specific DMA ops in a single place. For now, we deal with xen-swiotlb DMA ops only. The one of the subsequent commits in current series will add xen-grant DMA ops case. Also re-use the xen_swiotlb_detect() check on Arm32. Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> [For arm64] Acked-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/1654197833-25362-2-git-send-email-olekstysh@gmail.com Signed-off-by: Juergen Gross <jgross@suse.com>
2022-05-27arm64/hugetlb: Fix building errors in huge_ptep_clear_flush()Baolin Wang1-1/+4
Fix the arm64 build error which was caused by commit ae07562909f3 ("mm: change huge_ptep_clear_flush() to return the original pte") interacting with commit fb396bb459c1 ("arm64/hugetlb: Drop TLB flush from get_clear_flush()"): arch/arm64/mm/hugetlbpage.c: In function ‘huge_ptep_clear_flush’: arch/arm64/mm/hugetlbpage.c:515:9: error: implicit declaration of function ‘get_clear_flush’; did you mean ‘ptep_clear_flush’? [-Werror=implicit-function-declaration] 515 | return get_clear_flush(vma->vm_mm, addr, ptep, pgsize, ncontig); | ^~~~~~~~~~~~~~~ | ptep_clear_flush Due to the new get_clear_contig() has dropped TLB flush, we should add an explicit TLB flush in huge_ptep_clear_flush() to keep original semantics when changing to use new get_clear_contig(). Fixes: fb396bb459c1 ("arm64/hugetlb: Drop TLB flush from get_clear_flush()"). Fixes: ae07562909f3 ("mm: change huge_ptep_clear_flush() to return the original pte") Reported-and-tested-by: Linux Kernel Functional Testing <lkft@linaro.org> Reported-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com> Suggested-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> Reviewed-by: Gavin Shan <gshan@redhat.com> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-05-26Merge tag 'mm-stable-2022-05-25' of ↵Linus Torvalds3-7/+44
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: "Almost all of MM here. A few things are still getting finished off, reviewed, etc. - Yang Shi has improved the behaviour of khugepaged collapsing of readonly file-backed transparent hugepages. - Johannes Weiner has arranged for zswap memory use to be tracked and managed on a per-cgroup basis. - Munchun Song adds a /proc knob ("hugetlb_optimize_vmemmap") for runtime enablement of the recent huge page vmemmap optimization feature. - Baolin Wang contributes a series to fix some issues around hugetlb pagetable invalidation. - Zhenwei Pi has fixed some interactions between hwpoisoned pages and virtualization. - Tong Tiangen has enabled the use of the presently x86-only page_table_check debugging feature on arm64 and riscv. - David Vernet has done some fixup work on the memcg selftests. - Peter Xu has taught userfaultfd to handle write protection faults against shmem- and hugetlbfs-backed files. - More DAMON development from SeongJae Park - adding online tuning of the feature and support for monitoring of fixed virtual address ranges. Also easier discovery of which monitoring operations are available. - Nadav Amit has done some optimization of TLB flushing during mprotect(). - Neil Brown continues to labor away at improving our swap-over-NFS support. - David Hildenbrand has some fixes to anon page COWing versus get_user_pages(). - Peng Liu fixed some errors in the core hugetlb code. - Joao Martins has reduced the amount of memory consumed by device-dax's compound devmaps. - Some cleanups of the arch-specific pagemap code from Anshuman Khandual. - Muchun Song has found and fixed some errors in the TLB flushing of transparent hugepages. - Roman Gushchin has done more work on the memcg selftests. ... and, of course, many smaller fixes and cleanups. Notably, the customary million cleanup serieses from Miaohe Lin" * tag 'mm-stable-2022-05-25' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (381 commits) mm: kfence: use PAGE_ALIGNED helper selftests: vm: add the "settings" file with timeout variable selftests: vm: add "test_hmm.sh" to TEST_FILES selftests: vm: check numa_available() before operating "merge_across_nodes" in ksm_tests selftests: vm: add migration to the .gitignore selftests/vm/pkeys: fix typo in comment ksm: fix typo in comment selftests: vm: add process_mrelease tests Revert "mm/vmscan: never demote for memcg reclaim" mm/kfence: print disabling or re-enabling message include/trace/events/percpu.h: cleanup for "percpu: improve percpu_alloc_percpu event trace" include/trace/events/mmflags.h: cleanup for "tracing: incorrect gfp_t conversion" mm: fix a potential infinite loop in start_isolate_page_range() MAINTAINERS: add Muchun as co-maintainer for HugeTLB zram: fix Kconfig dependency warning mm/shmem: fix shmem folio swapoff hang cgroup: fix an error handling path in alloc_pagecache_max_30M() mm: damon: use HPAGE_PMD_SIZE tracing: incorrect isolate_mote_t cast in mm_vmscan_lru_isolate nodemask.h: fix compilation error with GCC12 ...
2022-05-26Merge tag 'dma-mapping-5.19-2022-05-25' of ↵Linus Torvalds1-5/+1
git://git.infradead.org/users/hch/dma-mapping Pull dma-mapping updates from Christoph Hellwig: - don't over-decrypt memory (Robin Murphy) - takes min align mask into account for the swiotlb max mapping size (Tianyu Lan) - use GFP_ATOMIC in dma-debug (Mikulas Patocka) - fix DMA_ATTR_NO_KERNEL_MAPPING on xen/arm (me) - don't fail on highmem CMA pages in dma_direct_alloc_pages (me) - cleanup swiotlb initialization and share more code with swiotlb-xen (me, Stefano Stabellini) * tag 'dma-mapping-5.19-2022-05-25' of git://git.infradead.org/users/hch/dma-mapping: (23 commits) dma-direct: don't over-decrypt memory swiotlb: max mapping size takes min align mask into account swiotlb: use the right nslabs-derived sizes in swiotlb_init_late swiotlb: use the right nslabs value in swiotlb_init_remap swiotlb: don't panic when the swiotlb buffer can't be allocated dma-debug: change allocation mode from GFP_NOWAIT to GFP_ATIOMIC dma-direct: don't fail on highmem CMA pages in dma_direct_alloc_pages swiotlb-xen: fix DMA_ATTR_NO_KERNEL_MAPPING on arm x86: remove cruft from <asm/dma-mapping.h> swiotlb: remove swiotlb_init_with_tbl and swiotlb_init_late_with_tbl swiotlb: merge swiotlb-xen initialization into swiotlb swiotlb: provide swiotlb_init variants that remap the buffer swiotlb: pass a gfp_mask argument to swiotlb_init_late swiotlb: add a SWIOTLB_ANY flag to lift the low memory restriction swiotlb: make the swiotlb_init interface more useful x86: centralize setting SWIOTLB_FORCE when guest memory encryption is enabled x86: remove the IOMMU table infrastructure MIPS/octeon: use swiotlb_init instead of open coding it arm/xen: don't check for xen_initial_domain() in xen_create_contiguous_region swiotlb: rename swiotlb_late_init_with_default_size ...
2022-05-24Merge tag 'arm64-upstream' of ↵Linus Torvalds5-63/+133
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Catalin Marinas: - Initial support for the ARMv9 Scalable Matrix Extension (SME). SME takes the approach used for vectors in SVE and extends this to provide architectural support for matrix operations. No KVM support yet, SME is disabled in guests. - Support for crashkernel reservations above ZONE_DMA via the 'crashkernel=X,high' command line option. - btrfs search_ioctl() fix for live-lock with sub-page faults. - arm64 perf updates: support for the Hisilicon "CPA" PMU for monitoring coherent I/O traffic, support for Arm's CMN-650 and CMN-700 interconnect PMUs, minor driver fixes, kerneldoc cleanup. - Kselftest updates for SME, BTI, MTE. - Automatic generation of the system register macros from a 'sysreg' file describing the register bitfields. - Update the type of the function argument holding the ESR_ELx register value to unsigned long to match the architecture register size (originally 32-bit but extended since ARMv8.0). - stacktrace cleanups. - ftrace cleanups. - Miscellaneous updates, most notably: arm64-specific huge_ptep_get(), avoid executable mappings in kexec/hibernate code, drop TLB flushing from get_clear_flush() (and rename it to get_clear_contig()), ARCH_NR_GPIO bumped to 2048 for ARCH_APPLE. * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (145 commits) arm64/sysreg: Generate definitions for FAR_ELx arm64/sysreg: Generate definitions for DACR32_EL2 arm64/sysreg: Generate definitions for CSSELR_EL1 arm64/sysreg: Generate definitions for CPACR_ELx arm64/sysreg: Generate definitions for CONTEXTIDR_ELx arm64/sysreg: Generate definitions for CLIDR_EL1 arm64/sve: Move sve_free() into SVE code section arm64: Kconfig.platforms: Add comments arm64: Kconfig: Fix indentation and add comments arm64: mm: avoid writable executable mappings in kexec/hibernate code arm64: lds: move special code sections out of kernel exec segment arm64/hugetlb: Implement arm64 specific huge_ptep_get() arm64/hugetlb: Use ptep_get() to get the pte value of a huge page arm64: kdump: Do not allocate crash low memory if not needed arm64/sve: Generate ZCR definitions arm64/sme: Generate defintions for SVCR arm64/sme: Generate SMPRI_EL1 definitions arm64/sme: Automatically generate SMPRIMAP_EL2 definitions arm64/sme: Automatically generate SMIDR_EL1 defines arm64/sme: Automatically generate defines for SMCR ...
2022-05-20Merge branch 'for-next/esr-elx-64-bit' into for-next/coreCatalin Marinas1-35/+35
* for-next/esr-elx-64-bit: : Treat ESR_ELx as a 64-bit register. KVM: arm64: uapi: Add kvm_debug_exit_arch.hsr_high KVM: arm64: Treat ESR_EL2 as a 64-bit register arm64: Treat ESR_ELx as a 64-bit register arm64: compat: Do not treat syscall number as ESR_ELx for a bad syscall arm64: Make ESR_ELx_xVC_IMM_MASK compatible with assembly
2022-05-20Merge branch 'for-next/sysreg-gen' into for-next/coreCatalin Marinas1-1/+2
* for-next/sysreg-gen: (32 commits) : Automatic system register definition generation. arm64/sysreg: Generate definitions for FAR_ELx arm64/sysreg: Generate definitions for DACR32_EL2 arm64/sysreg: Generate definitions for CSSELR_EL1 arm64/sysreg: Generate definitions for CPACR_ELx arm64/sysreg: Generate definitions for CONTEXTIDR_ELx arm64/sysreg: Generate definitions for CLIDR_EL1 arm64/sve: Generate ZCR definitions arm64/sme: Generate defintions for SVCR arm64/sme: Generate SMPRI_EL1 definitions arm64/sme: Automatically generate SMPRIMAP_EL2 definitions arm64/sme: Automatically generate SMIDR_EL1 defines arm64/sme: Automatically generate defines for SMCR arm64/sysreg: Support generation of RAZ fields arm64/sme: Remove _EL0 from name of SVCR - FIXME sysreg.h arm64/sme: Standardise bitfield names for SVCR arm64/sme: Drop SYS_ from SMIDR_EL1 defines arm64/fp: Rename SVE and SME LEN field name to _WIDTH arm64/fp: Make SVE and SME length register definition match architecture arm64/sysreg: fix odd line spacing arm64/sysreg: improve comment for regs without fields ...
2022-05-20Merge branches 'for-next/sme', 'for-next/stacktrace', ↵Catalin Marinas4-27/+96
'for-next/fault-in-subpage', 'for-next/misc', 'for-next/ftrace' and 'for-next/crashkernel', remote-tracking branch 'arm64/for-next/perf' into for-next/core * arm64/for-next/perf: perf/arm-cmn: Decode CAL devices properly in debugfs perf/arm-cmn: Fix filter_sel lookup perf/marvell_cn10k: Fix tad_pmu_event_init() to check pmu type first drivers/perf: hisi: Add Support for CPA PMU drivers/perf: hisi: Associate PMUs in SICL with CPUs online drivers/perf: arm_spe: Expose saturating counter to 16-bit perf/arm-cmn: Add CMN-700 support perf/arm-cmn: Refactor occupancy filter selector perf/arm-cmn: Add CMN-650 support dt-bindings: perf: arm-cmn: Add CMN-650 and CMN-700 perf: check return value of armpmu_request_irq() perf: RISC-V: Remove non-kernel-doc ** comments * for-next/sme: (30 commits) : Scalable Matrix Extensions support. arm64/sve: Move sve_free() into SVE code section arm64/sve: Make kernel FPU protection RT friendly arm64/sve: Delay freeing memory in fpsimd_flush_thread() arm64/sme: More sensibly define the size for the ZA register set arm64/sme: Fix NULL check after kzalloc arm64/sme: Add ID_AA64SMFR0_EL1 to __read_sysreg_by_encoding() arm64/sme: Provide Kconfig for SME KVM: arm64: Handle SME host state when running guests KVM: arm64: Trap SME usage in guest KVM: arm64: Hide SME system registers from guests arm64/sme: Save and restore streaming mode over EFI runtime calls arm64/sme: Disable streaming mode and ZA when flushing CPU state arm64/sme: Add ptrace support for ZA arm64/sme: Implement ptrace support for streaming mode SVE registers arm64/sme: Implement ZA signal handling arm64/sme: Implement streaming SVE signal handling arm64/sme: Disable ZA and streaming mode when handling signals arm64/sme: Implement traps and syscall handling for SME arm64/sme: Implement ZA context switching arm64/sme: Implement streaming SVE context switching ... * for-next/stacktrace: : Stacktrace cleanups. arm64: stacktrace: align with common naming arm64: stacktrace: rename stackframe to unwind_state arm64: stacktrace: rename unwinder functions arm64: stacktrace: make struct stackframe private to stacktrace.c arm64: stacktrace: delete PCS comment arm64: stacktrace: remove NULL task check from unwind_frame() * for-next/fault-in-subpage: : btrfs search_ioctl() live-lock fix using fault_in_subpage_writeable(). btrfs: Avoid live-lock in search_ioctl() on hardware with sub-page faults arm64: Add support for user sub-page fault probing mm: Add fault_in_subpage_writeable() to probe at sub-page granularity * for-next/misc: : Miscellaneous patches. arm64: Kconfig.platforms: Add comments arm64: Kconfig: Fix indentation and add comments arm64: mm: avoid writable executable mappings in kexec/hibernate code arm64: lds: move special code sections out of kernel exec segment arm64/hugetlb: Implement arm64 specific huge_ptep_get() arm64/hugetlb: Use ptep_get() to get the pte value of a huge page arm64: mm: Make arch_faults_on_old_pte() check for migratability arm64: mte: Clean up user tag accessors arm64/hugetlb: Drop TLB flush from get_clear_flush() arm64: Declare non global symbols as static arm64: mm: Cleanup useless parameters in zone_sizes_init() arm64: fix types in copy_highpage() arm64: Set ARCH_NR_GPIO to 2048 for ARCH_APPLE arm64: cputype: Avoid overflow using MIDR_IMPLEMENTOR_MASK arm64: document the boot requirements for MTE arm64/mm: Compute PTRS_PER_[PMD|PUD] independently of PTRS_PER_PTE * for-next/ftrace: : ftrace cleanups. arm64/ftrace: Make function graph use ftrace directly ftrace: cleanup ftrace_graph_caller enable and disable * for-next/crashkernel: : Support for crashkernel reservations above ZONE_DMA. arm64: kdump: Do not allocate crash low memory if not needed docs: kdump: Update the crashkernel description for arm64 of: Support more than one crash kernel regions for kexec -s of: fdt: Add memory for devices by DT property "linux,usable-memory-range" arm64: kdump: Reimplement crashkernel=X arm64: Use insert_resource() to simplify code kdump: return -ENOENT if required cmdline option does not exist
2022-05-17arm64: mm: avoid writable executable mappings in kexec/hibernate codeArd Biesheuvel1-1/+1
The temporary mappings of the low-level kexec and hibernate helpers are created with both writable and executable attributes, which is not necessary here, and generally best avoided. So use read-only, executable attributes instead. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Link: https://lore.kernel.org/r/20220429131347.3621090-3-ardb@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-05-17arm64/hugetlb: Implement arm64 specific huge_ptep_get()Baolin Wang1-0/+22
Now we use huge_ptep_get() to get the pte value of a hugetlb page, however it will only return one specific pte value for the CONT-PTE or CONT-PMD size hugetlb on ARM64 system, which can contain several continuous pte or pmd entries with same page table attributes. And it will not take into account the subpages' dirty or young bits of a CONT-PTE/PMD size hugetlb page. So the huge_ptep_get() is inconsistent with huge_ptep_get_and_clear(), which already takes account the dirty or young bits for any subpages in this CONT-PTE/PMD size hugetlb [1]. Meanwhile we can miss dirty or young flags statistics for hugetlb pages with current huge_ptep_get(), such as the gather_hugetlb_stats() function, and CONT-PTE/PMD hugetlb monitoring with DAMON. Thus define an ARM64 specific huge_ptep_get() implementation as well as enabling __HAVE_ARCH_HUGE_PTEP_GET, that will take into account any subpages' dirty or young bits for CONT-PTE/PMD size hugetlb page, for those functions that want to check the dirty and young flags of a hugetlb page. [1] https://lore.kernel.org/linux-mm/85bd80b4-b4fd-0d3f-a2e5-149559f2f387@oracle.com/ Suggested-by: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> Reviewed-by: Muchun Song <songmuchun@bytedance.com> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Link: https://lore.kernel.org/r/624109a80ac4bbdf1e462dfa0b49e9f7c31a7c0d.1652496622.git.baolin.wang@linux.alibaba.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-05-17arm64/hugetlb: Use ptep_get() to get the pte value of a huge pageBaolin Wang1-4/+4
The original huge_ptep_get() on ARM64 is just a wrapper of ptep_get(), which will not take into account any contig-PTEs dirty and access bits. Meanwhile we will implement a new ARM64-specific huge_ptep_get() interface in following patch, which will take into account any contig-PTEs dirty and access bits. To keep the same efficient logic to get the pte value, change to use ptep_get() as a preparation. Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> Reviewed-by: Muchun Song <songmuchun@bytedance.com> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Link: https://lore.kernel.org/r/5113ed6e103f995e1d0f0c9fda0373b761bbcad2.1652496622.git.baolin.wang@linux.alibaba.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-05-16arm64: kdump: Do not allocate crash low memory if not neededZhen Lei1-1/+2
When "crashkernel=X,high" is specified, the specified "crashkernel=Y,low" memory is not required in the following corner cases: 1. If both CONFIG_ZONE_DMA and CONFIG_ZONE_DMA32 are disabled, it means that the devices can access any memory. 2. If the system memory is small, the crash high memory may be allocated from the DMA zones. If that happens, there's no need to allocate another crash low memory because there's already one. Add condition '(crash_base >= CRASH_ADDR_LOW_MAX)' to determine whether the 'high' memory is allocated above DMA zones. Note: when both CONFIG_ZONE_DMA and CONFIG_ZONE_DMA32 are disabled, the entire physical memory is DMA accessible, CRASH_ADDR_LOW_MAX equals 'PHYS_MASK + 1'. Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> Acked-by: Baoquan He <bhe@redhat.com> Link: https://lore.kernel.org/r/20220511032033.426-1-thunder.leizhen@huawei.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-05-14mm: change huge_ptep_clear_flush() to return the original pteBaolin Wang1-7/+5
Patch series "Fix CONT-PTE/PMD size hugetlb issue when unmapping or migrating", v4. presently, migrating a hugetlb page or unmapping a poisoned hugetlb page, we'll use ptep_clear_flush() and set_pte_at() to nuke the page table entry and remap it, and this is incorrect for CONT-PTE or CONT-PMD size hugetlb page, which will cause potential data consistent issue. This patch set will change to use hugetlb related APIs to fix this issue. Note: Mike pointed out the huge_ptep_get() will only return the one specific value, and it would not take into account the dirty or young bits of CONT-PTE/PMDs like the huge_ptep_get_and_clear() [1]. This inconsistent issue is not introduced by this patch set, and this issue will be addressed in another thread [2]. Meanwhile the uffd for hugetlb case [3] pointed out by Gerald also needs another patch to address. [1] https://lore.kernel.org/linux-mm/85bd80b4-b4fd-0d3f-a2e5-149559f2f387@oracle.com/ [2] https://lore.kernel.org/all/cover.1651998586.git.baolin.wang@linux.alibaba.com/ [3] https://lore.kernel.org/linux-mm/20220503120343.6264e126@thinkpad/ This patch (of 3): It is incorrect to use ptep_clear_flush() to nuke a hugetlb page table when unmapping or migrating a hugetlb page, and will change to use huge_ptep_clear_flush() instead in the following patches. So this is a preparation patch, which changes the huge_ptep_clear_flush() to return the original pte to help to nuke a hugetlb page table. [baolin.wang@linux.alibaba.com: fix build in several more architectures] Link: https://lkml.kernel.org/r/0009a4cd-2826-e8be-e671-f050d4f18d5d@linux.alibaba.com [sfr@canb.auug.org.au: fixup] Link: https://lkml.kernel.org/r/20220511181531.7f27a5c1@canb.auug.org.au Link: https://lkml.kernel.org/r/cover.1652270205.git.baolin.wang@linux.alibaba.com Link: https://lkml.kernel.org/r/20f77ddab90baa249bd24504c413189b82acde69.1652270205.git.baolin.wang@linux.alibaba.com Link: https://lkml.kernel.org/r/cover.1652147571.git.baolin.wang@linux.alibaba.com Link: https://lkml.kernel.org/r/dcf065868cce35bceaf138613ad27f17bb7c0c19.1652147571.git.baolin.wang@linux.alibaba.com Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Acked-by: Mike Kravetz <mike.kravetz@oracle.com> Reviewed-by: Muchun Song <songmuchun@bytedance.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Cc: Helge Deller <deller@gmx.de> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Yoshinori Sato <ysato@users.osdn.me> Cc: Rich Felker <dalias@libc.org> Cc: David S. Miller <davem@davemloft.net> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-05-11arm64/hugetlb: Drop TLB flush from get_clear_flush()Anshuman Khandual1-11/+5
This drops now redundant TLB flush in get_clear_flush() which is no longer required after recent commit 697a1d44af8b ("tlb: hugetlb: Add more sizes to tlb_remove_huge_tlb_entry"). It also renames this function i.e dropping off '_flush' and replacing it with '__contig' as appropriate. Cc: Will Deacon <will@kernel.org> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Link: https://lore.kernel.org/r/20220510043930.2410985-1-anshuman.khandual@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-05-10arm[64]/memremap: don't abuse pfn_valid() to ensure presence of linear mapMike Rapoport1-0/+8
The semantics of pfn_valid() is to check presence of the memory map for a PFN and not whether a PFN is covered by the linear map. The memory map may be present for NOMAP memory regions, but they won't be mapped in the linear mapping. Accessing such regions via __va() when they are memremap()'ed will cause a crash. On v5.4.y the crash happens on qemu-arm with UEFI [1]: <1>[ 0.084476] 8<--- cut here --- <1>[ 0.084595] Unable to handle kernel paging request at virtual address dfb76000 <1>[ 0.084938] pgd = (ptrval) <1>[ 0.085038] [dfb76000] *pgd=5f7fe801, *pte=00000000, *ppte=00000000 ... <4>[ 0.093923] [<c0ed6ce8>] (memcpy) from [<c16a06f8>] (dmi_setup+0x60/0x418) <4>[ 0.094204] [<c16a06f8>] (dmi_setup) from [<c16a38d4>] (arm_dmi_init+0x8/0x10) <4>[ 0.094408] [<c16a38d4>] (arm_dmi_init) from [<c0302e9c>] (do_one_initcall+0x50/0x228) <4>[ 0.094619] [<c0302e9c>] (do_one_initcall) from [<c16011e4>] (kernel_init_freeable+0x15c/0x1f8) <4>[ 0.094841] [<c16011e4>] (kernel_init_freeable) from [<c0f028cc>] (kernel_init+0x8/0x10c) <4>[ 0.095057] [<c0f028cc>] (kernel_init) from [<c03010e8>] (ret_from_fork+0x14/0x2c) On kernels v5.10.y and newer the same crash won't reproduce on ARM because commit b10d6bca8720 ("arch, drivers: replace for_each_membock() with for_each_mem_range()") changed the way memory regions are registered in the resource tree, but that merely covers up the problem. On ARM64 memory resources registered in yet another way and there the issue of wrong usage of pfn_valid() to ensure availability of the linear map is also covered. Implement arch_memremap_can_ram_remap() on ARM and ARM64 to prevent access to NOMAP regions via the linear mapping in memremap(). Link: https://lore.kernel.org/all/Yl65zxGgFzF1Okac@sirena.org.uk Link: https://lkml.kernel.org/r/20220426060107.7618-1-rppt@kernel.org Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Reported-by: "kernelci.org bot" <bot@kernelci.org> Tested-by: Mark Brown <broonie@kernel.org> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Mark Brown <broonie@kernel.org> Cc: Mark-PK Tsai <mark-pk.tsai@mediatek.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Tony Lindgren <tony@atomide.com> Cc: Will Deacon <will@kernel.org> Cc: <stable@vger.kernel.org> [5.4+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-05-07arm64: kdump: Reimplement crashkernel=XChen Zhou1-6/+57
There are following issues in arm64 kdump: 1. We use crashkernel=X to reserve crashkernel in DMA zone, which will fail when there is not enough low memory. 2. If reserving crashkernel above DMA zone, in this case, crash dump kernel will fail to boot because there is no low memory available for allocation. To solve these issues, introduce crashkernel=X,[high,low]. The "crashkernel=X,high" is used to select a region above DMA zone, and the "crashkernel=Y,low" is used to allocate specified size low memory. Signed-off-by: Chen Zhou <chenzhou10@huawei.com> Co-developed-by: Zhen Lei <thunder.leizhen@huawei.com> Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> Link: https://lore.kernel.org/r/20220506114402.365-4-thunder.leizhen@huawei.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-05-07arm64: Use insert_resource() to simplify codeZhen Lei1-0/+1
insert_resource() traverses the subtree layer by layer from the root node until a proper location is found. Compared with request_resource(), the parent node does not need to be determined in advance. In addition, move the insertion of node 'crashk_res' into function reserve_crashkernel() to make the associated code close together. Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> Acked-by: John Donnelly <john.p.donnelly@oracle.com> Acked-by: Baoquan He <bhe@redhat.com> Link: https://lore.kernel.org/r/20220506114402.365-3-thunder.leizhen@huawei.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-05-05arm64: mm: Cleanup useless parameters in zone_sizes_init()Kefeng Wang1-3/+3
Directly use max_pfn for max and no one use min, kill them. Reviewed-by: Vijay Balakrishna <vijayb@linux.microsoft.com> Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Link: https://lore.kernel.org/r/20220411092455.1461-4-wangkefeng.wang@huawei.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-05-04arm64: fix types in copy_highpage()Tong Tiangen1-2/+2
In copy_highpage() the `kto` and `kfrom` local variables are pointers to struct page, but these are used to hold arbitrary pointers to kernel memory . Each call to page_address() returns a void pointer to memory associated with the relevant page, and copy_page() expects void pointers to this memory. This inconsistency was introduced in commit 2563776b41c3 ("arm64: mte: Tags-aware copy_{user_,}highpage() implementations") and while this doesn't appear to be harmful in practice it is clearly wrong. Correct this by making `kto` and `kfrom` void pointers. Fixes: 2563776b41c3 ("arm64: mte: Tags-aware copy_{user_,}highpage() implementations") Signed-off-by: Tong Tiangen <tongtiangen@huawei.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Kefeng Wang <wangkefeng.wang@huawei.com> Link: https://lore.kernel.org/r/20220420030418.3189040-3-tongtiangen@huawei.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-05-04arm64/mte: Make TCF field values and naming more standardMark Brown1-1/+2
In preparation for automatic generation of the defines for system registers make the values used for the enumeration in SCTLR_ELx.TCF suitable for use with the newly defined SYS_FIELD_PREP_ENUM helper, removing the shift from the define and using the helper to generate it on use instead. Since we only ever interact with this field in EL1 and in preparation for generation of the defines also rename from SCTLR_ELx to SCTLR_EL1. SCTLR_EL2 is not quite the same as SCTLR_EL1 so the conversion does not share the field definitions. There should be no functional change from this patch. Signed-off-by: Mark Brown <broonie@kernel.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Link: https://lore.kernel.org/r/20220503170233.507788-4-broonie@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-04-29arm64: Treat ESR_ELx as a 64-bit registerAlexandru Elisei1-35/+35
In the initial release of the ARM Architecture Reference Manual for ARMv8-A, the ESR_ELx registers were defined as 32-bit registers. This changed in 2018 with version D.a (ARM DDI 0487D.a) of the architecture, when they became 64-bit registers, with bits [63:32] defined as RES0. In version G.a, a new field was added to ESR_ELx, ISS2, which covers bits [36:32]. This field is used when the Armv8.7 extension FEAT_LS64 is implemented. As a result of the evolution of the register width, Linux stores it as both a 64-bit value and a 32-bit value, which hasn't affected correctness so far as Linux only uses the lower 32 bits of the register. Make the register type consistent and always treat it as 64-bit wide. The register is redefined as an "unsigned long", which is an unsigned double-word (64-bit quantity) for the LP64 machine (aapcs64 [1], Table 1, page 14). The type was chosen because "unsigned int" is the most frequent type for ESR_ELx and because FAR_ELx, which is used together with ESR_ELx in exception handling, is also declared as "unsigned long". The 64-bit type also makes adding support for architectural features that use fields above bit 31 easier in the future. The KVM hypervisor will receive a similar update in a subsequent patch. [1] https://github.com/ARM-software/abi-aa/releases/download/2021Q3/aapcs64.pdf Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com> Reviewed-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220425114444.368693-4-alexandru.elisei@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-04-29mm: hugetlb_vmemmap: cleanup CONFIG_HUGETLB_PAGE_FREE_VMEMMAP*Muchun Song1-1/+1
The word of "free" is not expressive enough to express the feature of optimizing vmemmap pages associated with each HugeTLB, rename this keywork to "optimize". In this patch , cheanup configs to make code more expressive. Link: https://lkml.kernel.org/r/20220404074652.68024-4-songmuchun@bytedance.com Signed-off-by: Muchun Song <songmuchun@bytedance.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-04-29mm: hugetlb_vmemmap: cleanup hugetlb_free_vmemmap_enabled*Muchun Song1-1/+1
The word of "free" is not expressive enough to express the feature of optimizing vmemmap pages associated with each HugeTLB, rename this keywork to "optimize". In this patch , cheanup the static key and hugetlb_free_vmemmap_enabled() to make code more expressive. Link: https://lkml.kernel.org/r/20220404074652.68024-3-songmuchun@bytedance.com Signed-off-by: Muchun Song <songmuchun@bytedance.com> Cc: David Hildenbrand <david@redhat.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-04-29arm64/mm: enable ARCH_HAS_VM_GET_PAGE_PROTAnshuman Khandual1-0/+25
This defines and exports a platform specific custom vm_get_page_prot() via subscribing ARCH_HAS_VM_GET_PAGE_PROT. It localizes arch_vm_get_page_prot() and moves it near vm_get_page_prot(). Link: https://lkml.kernel.org/r/20220414062125.609297-4-anshuman.khandual@arm.com Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Christoph Hellwig <hch@infradead.org> Cc: David S. Miller <davem@davemloft.net> Cc: Ingo Molnar <mingo@redhat.com> Cc: Khalid Aziz <khalid.aziz@oracle.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-04-29arm64: mm: hugetlb: enable HUGETLB_PAGE_FREE_VMEMMAP for arm64Muchun Song1-0/+14
The feature of minimizing overhead of struct page associated with each HugeTLB page aims to free its vmemmap pages (used as struct page) to save memory, where is ~14GB/16GB per 1TB HugeTLB pages (2MB/1GB type). In short, when a HugeTLB page is allocated or freed, the vmemmap array representing the range associated with the page will need to be remapped. When a page is allocated, vmemmap pages are freed after remapping. When a page is freed, previously discarded vmemmap pages must be allocated before remapping. More implementations and details can be found here [1]. The infrastructure of freeing vmemmap pages associated with each HugeTLB page is already there, we can easily enable HUGETLB_PAGE_FREE_VMEMMAP for arm64, the only thing to be fixed is flush_dcache_page() . flush_dcache_page() need to be adapted to operate on the head page's flags since the tail vmemmap pages are mapped with read-only after the feature is enabled (clear operation is not permitted). There was some discussions about this in the thread [2], but there was no conclusion in the end. And I copied the concern proposed by Anshuman to here and explain why those concern is superfluous. It is safe to enable it for x86_64 as well as arm64. 1st concern: ''' But what happens when a hot remove section's vmemmap area (which is being teared down) is nearby another vmemmap area which is either created or being destroyed for HugeTLB alloc/free purpose. As you mentioned HugeTLB pages inside the hot remove section might be safe. But what about other HugeTLB areas whose vmemmap area shares page table entries with vmemmap entries for a section being hot removed ? Massive HugeTLB alloc /use/free test cycle using memory just adjacent to a memory hotplug area, which is always added and removed periodically, should be able to expose this problem. ''' Answer: At the time memory is removed, all HugeTLB pages either have been migrated away or dissolved. So there is no race between memory hot remove and free_huge_page_vmemmap(). Therefore, HugeTLB pages inside the hot remove section is safe. Let's talk your question "what about other HugeTLB areas whose vmemmap area shares page table entries with vmemmap entries for a section being hot removed ?", the question is not established. The minimal granularity size of hotplug memory 128MB (on arm64, 4k base page), any HugeTLB smaller than 128MB is within a section, then, there is no share PTE page tables between HugeTLB in this section and ones in other sections and a HugeTLB page could not cross two sections. In this case, the section cannot be freed. Any HugeTLB bigger than 128MB (section size) whose vmemmap pages is an integer multiple of 2MB (PMD-mapped). As long as: 1) HugeTLBs are naturally aligned, power-of-two sizes 2) The HugeTLB size >= the section size 3) The HugeTLB size >= the vmemmap leaf mapping size Then a HugeTLB will not share any leaf page table entries with *anything else*, but will share intermediate entries. In this case, at the time memory is removed, all HugeTLB pages either have been migrated away or dissolved. So there is also no race between memory hot remove and free_huge_page_vmemmap(). 2nd concern: ''' differently, not sure if ptdump would require any synchronization. Dumping an wrong value is probably okay but crashing because a page table entry is being freed after ptdump acquired the pointer is bad. On arm64, ptdump() is protected against hotremove via [get|put]_online_mems(). ''' Answer: The ptdump should be fine since vmemmap_remap_free() only exchanges PTEs or splits the PMD entry (which means allocating a PTE page table). Both operations do not free any page tables (PTE), so ptdump cannot run into a UAF on any page tables. The worst case is just dumping an wrong value. [1] https://lore.kernel.org/all/20210510030027.56044-1-songmuchun@bytedance.com/ [2] https://lore.kernel.org/all/20210518091826.36937-1-songmuchun@bytedance.com/ [songmuchun@bytedance.com: restructure the code comment inside flush_dcache_page()] Link: https://lkml.kernel.org/r/20220414072646.21910-1-songmuchun@bytedance.com Link: https://lkml.kernel.org/r/20220331065640.5777-2-songmuchun@bytedance.com Signed-off-by: Muchun Song <songmuchun@bytedance.com> Reviewed-by: Barry Song <baohua@kernel.org> Tested-by: Barry Song <baohua@kernel.org> Cc: Will Deacon <will@kernel.org> Cc: David Hildenbrand <david@redhat.com> Cc: Bodeddula Balasubramaniam <bodeddub@amazon.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: David Rientjes <rientjes@google.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Xiongchun Duan <duanxiongchun@bytedance.com> Cc: Fam Zheng <fam.zheng@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-04-18swiotlb: make the swiotlb_init interface more usefulChristoph Hellwig1-5/+1
Pass a boolean flag to indicate if swiotlb needs to be enabled based on the addressing needs, and replace the verbose argument with a set of flags, including one to force enable bounce buffering. Note that this patch removes the possibility to force xen-swiotlb use with the swiotlb=force parameter on the command line on x86 (arm and arm64 never supported that), but this interface will be restored shortly. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2022-04-04arm64: fix typos in commentsJulia Lawall1-2/+2
Various spelling mistakes in comments. Detected with the help of Coccinelle. Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr> Link: https://lore.kernel.org/r/20220318103729.157574-10-Julia.Lawall@inria.fr [will: Squashed in 20220318103729.157574-28-Julia.Lawall@inria.fr] Signed-off-by: Will Deacon <will@kernel.org>
2022-03-25kasan, arm64: don't tag executable vmalloc allocationsAndrey Konovalov1-1/+1
Besides asking vmalloc memory to be executable via the prot argument of __vmalloc_node_range() (see the previous patch), the kernel can skip that bit and instead mark memory as executable via set_memory_x(). Once tag-based KASAN modes start tagging vmalloc allocations, executing code from such allocations will lead to the PC register getting a tag, which is not tolerated by the kernel. Generic kernel code typically allocates memory via module_alloc() if it intends to mark memory as executable. (On arm64 module_alloc() uses __vmalloc_node_range() without setting the executable bit). Thus, reset pointer tags of pointers returned from module_alloc(). However, on arm64 there's an exception: the eBPF subsystem. Instead of using module_alloc(), it uses vmalloc() (via bpf_jit_alloc_exec()) to allocate its JIT region. Thus, reset pointer tags of pointers returned from bpf_jit_alloc_exec(). Resetting tags for these pointers results in untagged pointers being passed to set_memory_x(). This causes conflicts in arithmetic checks in change_memory_common(), as vm_struct->addr pointer returned by find_vm_area() is tagged. Reset pointer tag of find_vm_area(addr)->addr in change_memory_common(). Link: https://lkml.kernel.org/r/b7b2595423340cd7d76b770e5d519acf3b72f0ab.1643047180.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Marco Elver <elver@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Evgenii Stepanov <eugenis@google.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Collingbourne <pcc@google.com> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-25Merge branch 'akpm' (patches from Andrew)Linus Torvalds1-6/+3
Merge more updates from Andrew Morton: "Various misc subsystems, before getting into the post-linux-next material. 41 patches. Subsystems affected by this patch series: procfs, misc, core-kernel, lib, checkpatch, init, pipe, minix, fat, cgroups, kexec, kdump, taskstats, panic, kcov, resource, and ubsan" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (41 commits) Revert "ubsan, kcsan: Don't combine sanitizer with kcov on clang" kernel/resource: fix kfree() of bootmem memory again kcov: properly handle subsequent mmap calls kcov: split ioctl handling into locked and unlocked parts panic: move panic_print before kmsg dumpers panic: add option to dump all CPUs backtraces in panic_print docs: sysctl/kernel: add missing bit to panic_print taskstats: remove unneeded dead assignment kasan: no need to unset panic_on_warn in end_report() ubsan: no need to unset panic_on_warn in ubsan_epilogue() panic: unset panic_on_warn inside panic() docs: kdump: add scp example to write out the dump file docs: kdump: update description about sysfs file system support arm64: mm: use IS_ENABLED(CONFIG_KEXEC_CORE) instead of #ifdef x86/setup: use IS_ENABLED(CONFIG_KEXEC_CORE) instead of #ifdef riscv: mm: init: use IS_ENABLED(CONFIG_KEXEC_CORE) instead of #ifdef kexec: make crashk_res, crashk_low_res and crash_notes symbols always visible cgroup: use irqsave in cgroup_rstat_flush_locked(). fat: use pointer to simple type in put_user() minix: fix bug when opening a file with O_DIRECT ...
2022-03-24arm64: mm: use IS_ENABLED(CONFIG_KEXEC_CORE) instead of #ifdefJisheng Zhang1-6/+3
Replace the conditional compilation using "#ifdef CONFIG_KEXEC_CORE" by a check for "IS_ENABLED(CONFIG_KEXEC_CORE)", to simplify the code and increase compile coverage. Link: https://lkml.kernel.org/r/20211206160514.2000-5-jszhang@kernel.org Signed-off-by: Jisheng Zhang <jszhang@kernel.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Baoquan He <bhe@redhat.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Alexandre Ghiti <alex@ghiti.fr> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Palmer Dabbelt <palmer@rivosinc.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-23Merge tag 'folio-5.18c' of git://git.infradead.org/users/willy/pagecacheLinus Torvalds1-0/+1
Pull folio updates from Matthew Wilcox: - Rewrite how munlock works to massively reduce the contention on i_mmap_rwsem (Hugh Dickins): https://lore.kernel.org/linux-mm/8e4356d-9622-a7f0-b2c-f116b5f2efea@google.com/ - Sort out the page refcount mess for ZONE_DEVICE pages (Christoph Hellwig): https://lore.kernel.org/linux-mm/20220210072828.2930359-1-hch@lst.de/ - Convert GUP to use folios and make pincount available for order-1 pages. (Matthew Wilcox) - Convert a few more truncation functions to use folios (Matthew Wilcox) - Convert page_vma_mapped_walk to use PFNs instead of pages (Matthew Wilcox) - Convert rmap_walk to use folios (Matthew Wilcox) - Convert most of shrink_page_list() to use a folio (Matthew Wilcox) - Add support for creating large folios in readahead (Matthew Wilcox) * tag 'folio-5.18c' of git://git.infradead.org/users/willy/pagecache: (114 commits) mm/damon: minor cleanup for damon_pa_young selftests/vm/transhuge-stress: Support file-backed PMD folios mm/filemap: Support VM_HUGEPAGE for file mappings mm/readahead: Switch to page_cache_ra_order mm/readahead: Align file mappings for non-DAX mm/readahead: Add large folio readahead mm: Support arbitrary THP sizes mm: Make large folios depend on THP mm: Fix READ_ONLY_THP warning mm/filemap: Allow large folios to be added to the page cache mm: Turn can_split_huge_page() into can_split_folio() mm/vmscan: Convert pageout() to take a folio mm/vmscan: Turn page_check_references() into folio_check_references() mm/vmscan: Account large folios correctly mm/vmscan: Optimise shrink_page_list for non-PMD-sized folios mm/vmscan: Free non-shmem folios without splitting them mm/rmap: Constify the rmap_walk_control argument mm/rmap: Convert rmap_walk() to take a folio mm: Turn page_anon_vma() into folio_anon_vma() mm/rmap: Turn page_lock_anon_vma_read() into folio_lock_anon_vma_read() ...
2022-03-23Merge branch 'akpm' (patches from Andrew)Linus Torvalds1-0/+1
Merge updates from Andrew Morton: - A few misc subsystems: kthread, scripts, ntfs, ocfs2, block, and vfs - Most the MM patches which precede the patches in Willy's tree: kasan, pagecache, gup, swap, shmem, memcg, selftests, pagemap, mremap, sparsemem, vmalloc, pagealloc, memory-failure, mlock, hugetlb, userfaultfd, vmscan, compaction, mempolicy, oom-kill, migration, thp, cma, autonuma, psi, ksm, page-poison, madvise, memory-hotplug, rmap, zswap, uaccess, ioremap, highmem, cleanups, kfence, hmm, and damon. * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (227 commits) mm/damon/sysfs: remove repeat container_of() in damon_sysfs_kdamond_release() Docs/ABI/testing: add DAMON sysfs interface ABI document Docs/admin-guide/mm/damon/usage: document DAMON sysfs interface selftests/damon: add a test for DAMON sysfs interface mm/damon/sysfs: support DAMOS stats mm/damon/sysfs: support DAMOS watermarks mm/damon/sysfs: support schemes prioritization mm/damon/sysfs: support DAMOS quotas mm/damon/sysfs: support DAMON-based Operation Schemes mm/damon/sysfs: support the physical address space monitoring mm/damon/sysfs: link DAMON for virtual address spaces monitoring mm/damon: implement a minimal stub for sysfs-based DAMON interface mm/damon/core: add number of each enum type values mm/damon/core: allow non-exclusive DAMON start/stop Docs/damon: update outdated term 'regions update interval' Docs/vm/damon/design: update DAMON-Idle Page Tracking interference handling Docs/vm/damon: call low level monitoring primitives the operations mm/damon: remove unnecessary CONFIG_DAMON option mm/damon/paddr,vaddr: remove damon_{p,v}a_{target_valid,set_operations}() mm/damon/dbgfs-test: fix is_target_id() change ...
2022-03-23mm: merge pte_mkhuge() call into arch_make_huge_pte()Anshuman Khandual1-0/+1
Each call into pte_mkhuge() is invariably followed by arch_make_huge_pte(). Instead arch_make_huge_pte() can accommodate pte_mkhuge() at the beginning. This updates generic fallback stub for arch_make_huge_pte() and available platforms definitions. This makes huge pte creation much cleaner and easier to follow. Link: https://lkml.kernel.org/r/1643860669-26307-1-git-send-email-anshuman.khandual@arm.com Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu> Acked-by: Mike Kravetz <mike.kravetz@oracle.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Mike Kravetz <mike.kravetz@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-21Merge tag 'arm64-upstream' of ↵Linus Torvalds7-54/+122
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Will Deacon: - Support for including MTE tags in ELF coredumps - Instruction encoder updates, including fixes to 64-bit immediate generation and support for the LSE atomic instructions - Improvements to kselftests for MTE and fpsimd - Symbol aliasing and linker script cleanups - Reduce instruction cache maintenance performed for user mappings created using contiguous PTEs - Support for the new "asymmetric" MTE mode, where stores are checked asynchronously but loads are checked synchronously - Support for the latest pointer authentication algorithm ("QARMA3") - Support for the DDR PMU present in the Marvell CN10K platform - Support for the CPU PMU present in the Apple M1 platform - Use the RNDR instruction for arch_get_random_{int,long}() - Update our copy of the Arm optimised string routines for str{n}cmp() - Fix signal frame generation for CPUs which have foolishly elected to avoid building in support for the fpsimd instructions - Workaround for Marvell GICv3 erratum #38545 - Clarification to our Documentation (booting reqs. and MTE prctl()) - Miscellanous cleanups and minor fixes * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (90 commits) docs: sysfs-devices-system-cpu: document "asymm" value for mte_tcf_preferred arm64/mte: Remove asymmetric mode from the prctl() interface arm64: Add cavium_erratum_23154_cpus missing sentinel perf/marvell: Fix !CONFIG_OF build for CN10K DDR PMU driver arm64: mm: Drop 'const' from conditional arm64_dma_phys_limit definition Documentation: vmcoreinfo: Fix htmldocs warning kasan: fix a missing header include of static_keys.h drivers/perf: Add Apple icestorm/firestorm CPU PMU driver drivers/perf: arm_pmu: Handle 47 bit counters arm64: perf: Consistently make all event numbers as 16-bits arm64: perf: Expose some Armv9 common events under sysfs perf/marvell: cn10k DDR perf event core ownership perf/marvell: cn10k DDR perfmon event overflow handling perf/marvell: CN10k DDR performance monitor support dt-bindings: perf: marvell: cn10k ddr performance monitor arm64: clean up tools Makefile perf/arm-cmn: Update watchpoint format perf/arm-cmn: Hide XP PUB events for CMN-600 arm64: drop unused includes of <linux/personality.h> arm64: Do not defer reserve_crashkernel() for platforms with no DMA memory zones ...
2022-03-14Merge branch 'for-next/spectre-bhb' into for-next/coreWill Deacon1-3/+9
Merge in the latest Spectre mess to fix up conflicts with what was already queued for 5.18 when the embargo finally lifted. * for-next/spectre-bhb: (21 commits) arm64: Do not include __READ_ONCE() block in assembly files arm64: proton-pack: Include unprivileged eBPF status in Spectre v2 mitigation reporting arm64: Use the clearbhb instruction in mitigations KVM: arm64: Allow SMCCC_ARCH_WORKAROUND_3 to be discovered and migrated arm64: Mitigate spectre style branch history side channels arm64: proton-pack: Report Spectre-BHB vulnerabilities as part of Spectre-v2 arm64: Add percpu vectors for EL1 arm64: entry: Add macro for reading symbol addresses from the trampoline arm64: entry: Add vectors that have the bhb mitigation sequences arm64: entry: Add non-kpti __bp_harden_el1_vectors for mitigations arm64: entry: Allow the trampoline text to occupy multiple pages arm64: entry: Make the kpti trampoline's kpti sequence optional arm64: entry: Move trampoline macros out of ifdef'd section arm64: entry: Don't assume tramp_vectors is the start of the vectors arm64: entry: Allow tramp_alias to access symbols after the 4K boundary arm64: entry: Move the trampoline data page before the text page arm64: entry: Free up another register on kpti's tramp_exit path arm64: entry: Make the trampoline cleanup optional KVM: arm64: Allow indirect vectors to be used without SPECTRE_V3A arm64: spectre: Rename spectre_v4_patch_fw_mitigation_conduit ...
2022-03-14Merge branch 'for-next/mm' into for-next/coreWill Deacon4-34/+37
* for-next/mm: Documentation: vmcoreinfo: Fix htmldocs warning arm64/mm: Drop use_1G_block() arm64: avoid flushing icache multiple times on contiguous HugeTLB arm64: crash_core: Export MODULES, VMALLOC, and VMEMMAP ranges arm64/hugetlb: Define __hugetlb_valid_size() arm64/mm: avoid fixmap race condition when create pud mapping arm64/mm: Consolidate TCR_EL1 fields
2022-03-14Merge branch 'for-next/misc' into for-next/coreWill Deacon2-5/+63
* for-next/misc: arm64: mm: Drop 'const' from conditional arm64_dma_phys_limit definition arm64: clean up tools Makefile arm64: drop unused includes of <linux/personality.h> arm64: Do not defer reserve_crashkernel() for platforms with no DMA memory zones arm64: prevent instrumentation of bp hardening callbacks arm64: cpufeature: Remove cpu_has_fwb() check arm64: atomics: remove redundant static branch arm64: entry: Save some nops when CONFIG_ARM64_PSEUDO_NMI is not set
2022-03-14Merge branch 'for-next/linkage' into for-next/coreWill Deacon1-14/+21
* for-next/linkage: arm64: module: remove (NOLOAD) from linker script linkage: remove SYM_FUNC_{START,END}_ALIAS() x86: clean up symbol aliasing arm64: clean up symbol aliasing linkage: add SYM_FUNC_ALIAS{,_LOCAL,_WEAK}()
2022-03-09Merge tag 'arm64-fixes' of ↵Linus Torvalds1-0/+17
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 fixes from Catalin Marinas: - Fix compilation of eBPF object files that indirectly include mte-kasan.h. - Fix test for execute-only permissions with EPAN (Enhanced Privileged Access Never, ARMv8.7 feature). * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64: kasan: fix include error in MTE functions arm64: Ensure execute-only permissions are not allowed without EPAN
2022-03-09arm64: mm: Drop 'const' from conditional arm64_dma_phys_limit definitionWill Deacon1-1/+1
Commit 031495635b46 ("arm64: Do not defer reserve_crashkernel() for platforms with no DMA memory zones") introduced different definitions for 'arm64_dma_phys_limit' depending on CONFIG_ZONE_DMA{,32} based on a late suggestion from Pasha. Sadly, this results in a build error when passing W=1: | arch/arm64/mm/init.c:90:19: error: conflicting type qualifiers for 'arm64_dma_phys_limit' Drop the 'const' for now and use '__ro_after_init' consistently. Link: https://lore.kernel.org/r/202203090241.aj7paWeX-lkp@intel.com Link: https://lore.kernel.org/r/CA+CK2bDbbx=8R=UthkMesWOST8eJMtOGJdfMRTFSwVmo0Vn0EA@mail.gmail.com Fixes: 031495635b46 ("arm64: Do not defer reserve_crashkernel() for platforms with no DMA memory zones") Signed-off-by: Will Deacon <will@kernel.org>
2022-03-08arm64: Do not defer reserve_crashkernel() for platforms with no DMA memory zonesVijay Balakrishna2-5/+63
The following patches resulted in deferring crash kernel reservation to mem_init(), mainly aimed at platforms with DMA memory zones (no IOMMU), in particular Raspberry Pi 4. commit 1a8e1cef7603 ("arm64: use both ZONE_DMA and ZONE_DMA32") commit 8424ecdde7df ("arm64: mm: Set ZONE_DMA size based on devicetree's dma-ranges") commit 0a30c53573b0 ("arm64: mm: Move reserve_crashkernel() into mem_init()") commit 2687275a5843 ("arm64: Force NO_BLOCK_MAPPINGS if crashkernel reservation is required") Above changes introduced boot slowdown due to linear map creation for all the memory banks with NO_BLOCK_MAPPINGS, see discussion[1]. The proposed changes restore crash kernel reservation to earlier behavior thus avoids slow boot, particularly for platforms with IOMMU (no DMA memory zones). Tested changes to confirm no ~150ms boot slowdown on our SoC with IOMMU and 8GB memory. Also tested with ZONE_DMA and/or ZONE_DMA32 configs to confirm no regression to deferring scheme of crash kernel memory reservation. In both cases successfully collected kernel crash dump. [1] https://lore.kernel.org/all/9436d033-579b-55fa-9b00-6f4b661c2dd7@linux.microsoft.com/ Signed-off-by: Vijay Balakrishna <vijayb@linux.microsoft.com> Cc: stable@vger.kernel.org Reviewed-by: Pasha Tatashin <pasha.tatashin@soleen.com> Link: https://lore.kernel.org/r/1646242689-20744-1-git-send-email-vijayb@linux.microsoft.com [will: Add #ifdef CONFIG_KEXEC_CORE guards to fix 'crashk_res' references in allnoconfig build] Signed-off-by: Will Deacon <will@kernel.org>
2022-03-08arm64: Ensure execute-only permissions are not allowed without EPANCatalin Marinas1-0/+17
Commit 18107f8a2df6 ("arm64: Support execute-only permissions with Enhanced PAN") re-introduced execute-only permissions when EPAN is available. When EPAN is not available, arch_filter_pgprot() is supposed to change a PAGE_EXECONLY permission into PAGE_READONLY_EXEC. However, if BTI or MTE are present, such check does not detect the execute-only pgprot in the presence of PTE_GP (BTI) or MT_NORMAL_TAGGED (MTE), allowing the user to request PROT_EXEC with PROT_BTI or PROT_MTE. Remove the arch_filter_pgprot() function, change the default VM_EXEC permissions to PAGE_READONLY_EXEC and update the protection_map[] array at core_initcall() if EPAN is detected. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Fixes: 18107f8a2df6 ("arm64: Support execute-only permissions with Enhanced PAN") Cc: <stable@vger.kernel.org> # 5.13.x Acked-by: Will Deacon <will@kernel.org> Reviewed-by: Vladimir Murzin <vladimir.murzin@arm.com> Tested-by: Vladimir Murzin <vladimir.murzin@arm.com>
2022-03-08arm64/mm: Drop use_1G_block()Anshuman Khandual1-13/+2
pud_sect_supported() already checks for PUD level block mapping support i.e on ARM64_4K_PAGES config. Hence pud_sect_supported(), along with some other required alignment checks can help completely drop use_1G_block(). Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/1644988012-25455-1-git-send-email-anshuman.khandual@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2022-03-08arm64: avoid flushing icache multiple times on contiguous HugeTLBMuchun Song1-0/+7
When a contiguous HugeTLB page is mapped, set_pte_at() will be called CONT_PTES/CONT_PMDS times. Therefore, __sync_icache_dcache() will flush cache multiple times if the page is executable (to ensure the I-D cache coherency). However, the first flushing cache already covers subsequent cache flush operations. So only flusing cache for the head page if it is a HugeTLB page to avoid redundant cache flushing. In the next patch, it is also depends on this change since the tail vmemmap pages of HugeTLB is mapped with read-only meanning only head page struct can be modified. Signed-off-by: Muchun Song <songmuchun@bytedance.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20220302084624.33340-1-songmuchun@bytedance.com Signed-off-by: Will Deacon <will@kernel.org>
2022-03-03mm: don't include <linux/memremap.h> in <linux/mm.h>Christoph Hellwig1-0/+1
Move the check for the actual pgmap types that need the free at refcount one behavior into the out of line helper, and thus avoid the need to pull memremap.h into mm.h. Link: https://lkml.kernel.org/r/20220210072828.2930359-7-hch@lst.de Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Logan Gunthorpe <logang@deltatee.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Felix Kuehling <Felix.Kuehling@amd.com> Tested-by: "Sierra Guiza, Alejandro (Alex)" <alex.sierra@amd.com> Cc: Alex Deucher <alexander.deucher@amd.com> Cc: Alistair Popple <apopple@nvidia.com> Cc: Ben Skeggs <bskeggs@redhat.com> Cc: Chaitanya Kulkarni <kch@nvidia.com> Cc: Karol Herbst <kherbst@redhat.com> Cc: Lyude Paul <lyude@redhat.com> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Muchun Song <songmuchun@bytedance.com> Cc: "Pan, Xinhui" <Xinhui.Pan@amd.com> Cc: Ralph Campbell <rcampbell@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
2022-02-23arm64/hugetlb: Define __hugetlb_valid_size()Anshuman Khandual1-20/+18
arch_hugetlb_valid_size() can be just factored out to create another helper to be used in arch_hugetlb_migration_supported() as well. This just defines __hugetlb_valid_size() for that purpose. Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Link: https://lore.kernel.org/r/1645073557-6150-1-git-send-email-anshuman.khandual@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2022-02-22arm64: clean up symbol aliasingMark Rutland1-14/+21
Now that we have SYM_FUNC_ALIAS() and SYM_FUNC_ALIAS_WEAK(), use those to simplify and more consistently define function aliases across arch/arm64. Aliases are now defined in terms of a canonical function name. For position-independent functions I've made the __pi_<func> name the canonical name, and defined other alises in terms of this. The SYM_FUNC_{START,END}_PI(func) macros obscure the __pi_<func> name, and make this hard to seatch for. The SYM_FUNC_START_WEAK_PI() macro also obscures the fact that the __pi_<func> fymbol is global and the <func> symbol is weak. For clarity, I have removed these macros and used SYM_FUNC_{START,END}() directly with the __pi_<func> name. For example: SYM_FUNC_START_WEAK_PI(func) ... asm insns ... SYM_FUNC_END_PI(func) EXPORT_SYMBOL(func) ... becomes: SYM_FUNC_START(__pi_func) ... asm insns ... SYM_FUNC_END(__pi_func) SYM_FUNC_ALIAS_WEAK(func, __pi_func) EXPORT_SYMBOL(func) For clarity, where there are multiple annotations such as EXPORT_SYMBOL(), I've tried to keep annotations grouped by symbol. For example, where a function has a name and an alias which are both exported, this is organised as: SYM_FUNC_START(func) ... asm insns ... SYM_FUNC_END(func) EXPORT_SYMBOL(func) SYM_FUNC_ALIAS(alias, func) EXPORT_SYMBOL(alias) For consistency with the other string functions, I've defined strrchr as a position-independent function, as it can safely be used as such even though we have no users today. As we no longer use SYM_FUNC_{START,END}_ALIAS(), our local copies are removed. The common versions will be removed by a subsequent patch. There should be no functional change as a result of this patch. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Ard Biesheuvel <ardb@kernel.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Acked-by: Mark Brown <broonie@kernel.org> Cc: Joey Gouly <joey.gouly@arm.com> Cc: Will Deacon <will@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20220216162229.1076788-3-mark.rutland@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2022-02-16arm64: mte: Define the number of bytes for storing the tags in a pageCatalin Marinas1-1/+1
Rather than explicitly calculating the number of bytes for a compact tag storage format corresponding to a page, just add a MTE_PAGE_TAG_STORAGE macro. With the current MTE implementation of 4 bits per tag, we store 2 tags in a byte. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Luis Machado <luis.machado@linaro.org> Link: https://lore.kernel.org/r/20220131165456.2160675-4-catalin.marinas@arm.com Signed-off-by: Will Deacon <will@kernel.org>