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2019-12-06Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linuxLinus Torvalds2-14/+12
Pull arm64 fixes from Catalin Marinas: - ZONE_DMA32 initialisation fix when memblocks fall entirely within the first GB (used by ZONE_DMA in 5.5 for Raspberry Pi 4). - Couple of ftrace fixes following the FTRACE_WITH_REGS patchset. - access_ok() fix for the Tagged Address ABI when called from from a kernel thread (asynchronous I/O): the kthread does not have the TIF flags of the mm owner, so untag the user address unconditionally. - KVM compute_layout() called before the alternatives code patching. - Minor clean-ups. * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64: entry: refine comment of stack overflow check arm64: ftrace: fix ifdeffery arm64: KVM: Invoke compute_layout() before alternatives are applied arm64: Validate tagged addresses in access_ok() called from kernel threads arm64: mm: Fix column alignment for UXN in kernel_page_tables arm64: insn: consistently handle exit text arm64: mm: Fix initialisation of DMA zones on non-NUMA systems
2019-12-04arm64: mm: Fix column alignment for UXN in kernel_page_tablesMark Brown1-0/+1
UXN is the only individual PTE bit other than the PTE_ATTRINDX_MASK ones which doesn't have both a set and a clear value provided, meaning that the columns in the table won't all be aligned. The PTE_ATTRINDX_MASK values are all both mutually exclusive and longer so are listed last to make a single final column for those values. Ensure everything is aligned by providing a clear value for UXN. Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2019-12-04arm64: mm: Fix initialisation of DMA zones on non-NUMA systemsWill Deacon1-14/+11
John reports that the recently merged commit 1a8e1cef7603 ("arm64: use both ZONE_DMA and ZONE_DMA32") breaks the boot on his DB845C board: | Booting Linux on physical CPU 0x0000000000 [0x517f803c] | Linux version 5.4.0-mainline-10675-g957a03b9e38f | Machine model: Thundercomm Dragonboard 845c | [...] | Built 1 zonelists, mobility grouping on. Total pages: -188245 | Kernel command line: earlycon | firmware_class.path=/vendor/firmware/ androidboot.hardware=db845c | init=/init androidboot.boot_devices=soc/1d84000.ufshc | printk.devkmsg=on buildvariant=userdebug root=/dev/sda2 | androidboot.bootdevice=1d84000.ufshc androidboot.serialno=c4e1189c | androidboot.baseband=sda | msm_drm.dsi_display0=dsi_lt9611_1080_video_display: | androidboot.slot_suffix=_a skip_initramfs rootwait ro init=/init | | <hangs indefinitely here> This is because, when CONFIG_NUMA=n, zone_sizes_init() fails to handle memblocks that fall entirely within the ZONE_DMA region and erroneously ends up trying to add a negatively-sized region into the following ZONE_DMA32, which is later interpreted as a large unsigned region by the core MM code. Rework the non-NUMA implementation of zone_sizes_init() so that the start address of the memblock being processed is adjusted according to the end of the previous zone, which is then range-checked before updating the hole information of subsequent zones. Cc: Nicolas Saenz Julienne <nsaenzjulienne@suse.de> Cc: Christoph Hellwig <hch@lst.de> Cc: Bjorn Andersson <bjorn.andersson@linaro.org> Link: https://lore.kernel.org/lkml/CALAqxLVVcsmFrDKLRGRq7GewcW405yTOxG=KR3csVzQ6bXutkA@mail.gmail.com Fixes: 1a8e1cef7603 ("arm64: use both ZONE_DMA and ZONE_DMA32") Reported-by: John Stultz <john.stultz@linaro.org> Tested-by: John Stultz <john.stultz@linaro.org> Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2019-11-28Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux; tag 'dma-mapping-5.5' of git://git.infradead.org/users/hch/dma-mappingLinus Torvalds1-4/+4
Pull dma-mapping updates from Christoph Hellwig: - improve dma-debug scalability (Eric Dumazet) - tiny dma-debug cleanup (Dan Carpenter) - check for vmap memory in dma_map_single (Kees Cook) - check for dma_addr_t overflows in dma-direct when using DMA offsets (Nicolas Saenz Julienne) - switch the x86 sta2x11 SOC to use more generic DMA code (Nicolas Saenz Julienne) - fix arm-nommu dma-ranges handling (Vladimir Murzin) - use __initdata in CMA (Shyam Saini) - replace the bus dma mask with a limit (Nicolas Saenz Julienne) - merge the remapping helpers into the main dma-direct flow (me) - switch xtensa to the generic dma remap handling (me) - various cleanups around dma_capable (me) - remove unused dev arguments to various dma-noncoherent helpers (me) * 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux: * tag 'dma-mapping-5.5' of git://git.infradead.org/users/hch/dma-mapping: (22 commits) dma-mapping: treat dev->bus_dma_mask as a DMA limit dma-direct: exclude dma_direct_map_resource from the min_low_pfn check dma-direct: don't check swiotlb=force in dma_direct_map_resource dma-debug: clean up put_hash_bucket() powerpc: remove support for NULL dev in __phys_to_dma / __dma_to_phys dma-direct: avoid a forward declaration for phys_to_dma dma-direct: unify the dma_capable definitions dma-mapping: drop the dev argument to arch_sync_dma_for_* x86/PCI: sta2x11: use default DMA address translation dma-direct: check for overflows on 32 bit DMA addresses dma-debug: increase HASH_SIZE dma-debug: reorder struct dma_debug_entry fields xtensa: use the generic uncached segment support dma-mapping: merge the generic remapping helpers into dma-direct dma-direct: provide mmap and get_sgtable method overrides dma-direct: remove the dma_handle argument to __dma_direct_alloc_pages dma-direct: remove __dma_direct_free_pages usb: core: Remove redundant vmap checks kernel: dma-contiguous: mark CMA parameters __initdata/__initconst dma-debug: add a schedule point in debug_dma_dump_mappings() ...
2019-11-26Merge tag 'acpi-5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pmLinus Torvalds1-0/+2
Pull ACPI updates from Rafael Wysocki: "These update the ACPICA code in the kernel to upstream revision 20191018, add support for EFI specific purpose memory, update the ACPI EC driver to make it work on systems with hardware-reduced ACPI, improve ACPI-based device enumeration for some platforms, rework the lid blacklist handling in the button driver and add more lid quirks to it, unify ACPI _HID/_UID matching, fix assorted issues and clean up the code and documentation. Specifics: - Update the ACPICA code in the kernel to upstream revision 20191018 including: * Fixes for Clang warnings (Bob Moore) * Fix for possible overflow in get_tick_count() (Bob Moore) * Introduction of acpi_unload_table() (Bob Moore) * Debugger and utilities updates (Erik Schmauss) * Fix for unloading tables loaded via configfs (Nikolaus Voss) - Add support for EFI specific purpose memory to optionally allow either application-exclusive or core-kernel-mm managed access to differentiated memory (Dan Williams) - Fix and clean up processing of the HMAT table (Brice Goglin, Qian Cai, Tao Xu) - Update the ACPI EC driver to make it work on systems with hardware-reduced ACPI (Daniel Drake) - Always build in support for the Generic Event Device (GED) to allow one kernel binary to work both on systems with full hardware ACPI and hardware-reduced ACPI (Arjan van de Ven) - Fix the table unload mechanism to unregister platform devices created when the given table was loaded (Andy Shevchenko) - Rework the lid blacklist handling in the button driver and add more lid quirks to it (Hans de Goede) - Improve ACPI-based device enumeration for some platforms based on Intel BayTrail SoCs (Hans de Goede) - Add an OpRegion driver for the Cherry Trail Crystal Cove PMIC and prevent handlers from being registered for unhandled PMIC OpRegions (Hans de Goede) - Unify ACPI _HID/_UID matching (Andy Shevchenko) - Clean up documentation and comments (Cao jin, James Pack, Kacper PiwiƄski)" * tag 'acpi-5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (52 commits) ACPI: OSI: Shoot duplicate word ACPI: HMAT: use %u instead of %d to print u32 values ACPI: NUMA: HMAT: fix a section mismatch ACPI: HMAT: don't mix pxm and nid when setting memory target processor_pxm ACPI: NUMA: HMAT: Register "soft reserved" memory as an "hmem" device ACPI: NUMA: HMAT: Register HMAT at device_initcall level device-dax: Add a driver for "hmem" devices dax: Fix alloc_dax_region() compile warning lib: Uplevel the pmem "region" ida to a global allocator x86/efi: Add efi_fake_mem support for EFI_MEMORY_SP arm/efi: EFI soft reservation to memblock x86/efi: EFI soft reservation to E820 enumeration efi: Common enable/disable infrastructure for EFI soft reservation x86/efi: Push EFI_MEMMAP check into leaf routines efi: Enumerate EFI_MEMORY_SP ACPI: NUMA: Establish a new drivers/acpi/numa/ directory ACPICA: Update version to 20191018 ACPICA: debugger: remove leading whitespaces when converting a string to a buffer ACPICA: acpiexec: initialize all simple types and field units from user input ACPICA: debugger: add field unit support for acpi_db_get_next_token ...
2019-11-21Merge branch 'for-next/zone-dma' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux into dma-mapping-for-nextChristoph Hellwig1-24/+53
Pull in a stable branch from the arm64 tree that adds the zone_dma_bits variable to avoid creating hard to resolve conflicts with that addition.
2019-11-20dma-mapping: drop the dev argument to arch_sync_dma_for_*Christoph Hellwig1-4/+4
These are pure cache maintainance routines, so drop the unused struct device argument. Signed-off-by: Christoph Hellwig <hch@lst.de> Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2019-11-08Merge branches 'for-next/elf-hwcap-docs', 'for-next/smccc-conduit-cleanup', 'for-next/zone-dma', 'for-next/relax-icc_pmr_el1-sync', 'for-next/double-page-fault', 'for-next/misc', 'for-next/kselftest-arm64-signal' and 'for-next/kaslr-diagnostics' into for-next/coreCatalin Marinas3-40/+58
* for-next/elf-hwcap-docs: : Update the arm64 ELF HWCAP documentation docs/arm64: cpu-feature-registers: Rewrite bitfields that don't follow [e, s] docs/arm64: cpu-feature-registers: Documents missing visible fields docs/arm64: elf_hwcaps: Document HWCAP_SB docs/arm64: elf_hwcaps: sort the HWCAP{, 2} documentation by ascending value * for-next/smccc-conduit-cleanup: : SMC calling convention conduit clean-up firmware: arm_sdei: use common SMCCC_CONDUIT_* firmware/psci: use common SMCCC_CONDUIT_* arm: spectre-v2: use arm_smccc_1_1_get_conduit() arm64: errata: use arm_smccc_1_1_get_conduit() arm/arm64: smccc/psci: add arm_smccc_1_1_get_conduit() * for-next/zone-dma: : Reintroduction of ZONE_DMA for Raspberry Pi 4 support arm64: mm: reserve CMA and crashkernel in ZONE_DMA32 dma/direct: turn ARCH_ZONE_DMA_BITS into a variable arm64: Make arm64_dma32_phys_limit static arm64: mm: Fix unused variable warning in zone_sizes_init mm: refresh ZONE_DMA and ZONE_DMA32 comments in 'enum zone_type' arm64: use both ZONE_DMA and ZONE_DMA32 arm64: rename variables used to calculate ZONE_DMA32's size arm64: mm: use arm64_dma_phys_limit instead of calling max_zone_dma_phys() * for-next/relax-icc_pmr_el1-sync: : Relax ICC_PMR_EL1 (GICv3) accesses when ICC_CTLR_EL1.PMHE is clear arm64: Document ICC_CTLR_EL3.PMHE setting requirements arm64: Relax ICC_PMR_EL1 accesses when ICC_CTLR_EL1.PMHE is clear * for-next/double-page-fault: : Avoid a double page fault in __copy_from_user_inatomic() if hw does not support auto Access Flag mm: fix double page fault on arm64 if PTE_AF is cleared x86/mm: implement arch_faults_on_old_pte() stub on x86 arm64: mm: implement arch_faults_on_old_pte() on arm64 arm64: cpufeature: introduce helper cpu_has_hw_af() * for-next/misc: : Various fixes and clean-ups arm64: kpti: Add NVIDIA's Carmel core to the KPTI whitelist arm64: mm: Remove MAX_USER_VA_BITS definition arm64: mm: simplify the page end calculation in __create_pgd_mapping() arm64: print additional fault message when executing non-exec memory arm64: psci: Reduce the waiting time for cpu_psci_cpu_kill() arm64: pgtable: Correct typo in comment arm64: docs: cpu-feature-registers: Document ID_AA64PFR1_EL1 arm64: cpufeature: Fix typos in comment arm64/mm: Poison initmem while freeing with free_reserved_area() arm64: use generic free_initrd_mem() arm64: simplify syscall wrapper ifdeffery * for-next/kselftest-arm64-signal: : arm64-specific kselftest support with signal-related test-cases kselftest: arm64: fake_sigreturn_misaligned_sp kselftest: arm64: fake_sigreturn_bad_size kselftest: arm64: fake_sigreturn_duplicated_fpsimd kselftest: arm64: fake_sigreturn_missing_fpsimd kselftest: arm64: fake_sigreturn_bad_size_for_magic0 kselftest: arm64: fake_sigreturn_bad_magic kselftest: arm64: add helper get_current_context kselftest: arm64: extend test_init functionalities kselftest: arm64: mangle_pstate_invalid_mode_el[123][ht] kselftest: arm64: mangle_pstate_invalid_daif_bits kselftest: arm64: mangle_pstate_invalid_compat_toggle and common utils kselftest: arm64: extend toplevel skeleton Makefile * for-next/kaslr-diagnostics: : Provide diagnostics on boot for KASLR arm64: kaslr: Check command line before looking for a seed arm64: kaslr: Announce KASLR status on boot
2019-11-07arm/efi: EFI soft reservation to memblockDan Williams1-0/+2
UEFI 2.8 defines an EFI_MEMORY_SP attribute bit to augment the interpretation of the EFI Memory Types as "reserved for a specific purpose". The proposed Linux behavior for specific purpose memory is that it is reserved for direct-access (device-dax) by default and not available for any kernel usage, not even as an OOM fallback. Later, through udev scripts or another init mechanism, these device-dax claimed ranges can be reconfigured and hot-added to the available System-RAM with a unique node identifier. This device-dax management scheme implements "soft" in the "soft reserved" designation by allowing some or all of the reservation to be recovered as typical memory. This policy can be disabled at compile-time with CONFIG_EFI_SOFT_RESERVE=n, or runtime with efi=nosoftreserve. For this patch, update the ARM paths that consider EFI_CONVENTIONAL_MEMORY to optionally take the EFI_MEMORY_SP attribute into account as a reservation indicator. Publish the soft reservation as IORES_DESC_SOFT_RESERVED memory, similar to x86. (Based on an original patch by Ard) Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-11-07arm64: mm: reserve CMA and crashkernel in ZONE_DMA32Nicolas Saenz Julienne1-2/+2
With the introduction of ZONE_DMA in arm64 we moved the default CMA and crashkernel reservation into that area. This caused a regression on big machines that need big CMA and crashkernel reservations. Note that ZONE_DMA is only 1GB big. Restore the previous behavior as the wide majority of devices are OK with reserving these in ZONE_DMA32. The ones that need them in ZONE_DMA will configure it explicitly. Fixes: 1a8e1cef7603 ("arm64: use both ZONE_DMA and ZONE_DMA32") Reported-by: Qian Cai <cai@lca.pw> Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2019-11-06arm64: mm: simplify the page end calculation in __create_pgd_mapping()Masahiro Yamada1-3/+2
Calculate the page-aligned end address more simply. The local variable, "length" is unneeded. Reviewed-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2019-11-01dma/direct: turn ARCH_ZONE_DMA_BITS into a variableNicolas Saenz Julienne1-2/+7
Some architectures, notably ARM, are interested in tweaking this depending on their runtime DMA addressing limitations. Acked-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2019-10-29arm64: print additional fault message when executing non-exec memoryXiang Zheng1-0/+2
When attempting to executing non-executable memory, the fault message shows: Unable to handle kernel read from unreadable memory at virtual address ffff802dac469000 This may confuse someone, so add a new fault message for instruction abort. Acked-by: Will Deacon <will@kernel.org> Signed-off-by: Xiang Zheng <zhengxiang9@huawei.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2019-10-28Merge branch 'for-next/entry-s-to-c' into for-next/coreCatalin Marinas1-49/+13
Move the synchronous exception paths from entry.S into a C file to improve the code readability. * for-next/entry-s-to-c: arm64: entry-common: don't touch daif before bp-hardening arm64: Remove asmlinkage from updated functions arm64: entry: convert el0_sync to C arm64: entry: convert el1_sync to C arm64: add local_daif_inherit() arm64: Add prototypes for functions called by entry.S arm64: remove __exception annotations
2019-10-28arm64: Make arm64_dma32_phys_limit staticCatalin Marinas1-1/+1
This variable is only used in the arch/arm64/mm/init.c file for ZONE_DMA32 initialisation, no need to expose it. Reported-by: Will Deacon <will@kernel.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2019-10-28arm64: entry-common: don't touch daif before bp-hardeningJames Morse1-35/+1
The previous patches mechanically transformed the assembly version of entry.S to entry-common.c for synchronous exceptions. The C version of local_daif_restore() doesn't quite do the same thing as the assembly versions if pseudo-NMI is in use. In particular, | local_daif_restore(DAIF_PROCCTX_NOIRQ) will still allow pNMI to be delivered. This is not the behaviour do_el0_ia_bp_hardening() and do_sp_pc_abort() want as it should not be possible for the PMU handler to run as an NMI until the bp-hardening sequence has run. The bp-hardening calls were placed where they are because this was the first C code to run after the relevant exceptions. As we've now moved that point earlier, move the checks and calls earlier too. This makes it clearer that this stuff runs before any kind of exception, and saves modifying PSTATE twice. Signed-off-by: James Morse <james.morse@arm.com> Reviewed-by: Mark Rutland <mark.rutland@arm.com> Cc: Julien Thierry <julien.thierry.kdev@gmail.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2019-10-28arm64: Remove asmlinkage from updated functionsJames Morse1-9/+7
Now that the callers of these functions have moved into C, they no longer need the asmlinkage annotation. Remove it. Signed-off-by: James Morse <james.morse@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2019-10-28arm64: remove __exception annotationsJames Morse1-17/+17
Since commit 732674980139 ("arm64: unwind: reference pt_regs via embedded stack frame") arm64 has not used the __exception annotation to dump the pt_regs during stack tracing. in_exception_text() has no callers. This annotation is only used to blacklist kprobes, it means the same as __kprobes. Section annotations like this require the functions to be grouped together between the start/end markers, and placed according to the linker script. For kprobes we also have NOKPROBE_SYMBOL() which logs the symbol address in a section that kprobes parses and blacklists at boot. Using NOKPROBE_SYMBOL() instead lets kprobes publish the list of blacklisted symbols, and saves us from having an arm64 specific spelling of __kprobes. do_debug_exception() already has a NOKPROBE_SYMBOL() annotation. Signed-off-by: James Morse <james.morse@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2019-10-16arm64: mm: fix inverted PAR_EL1.F checkMark Rutland1-1/+5
When detecting a spurious EL1 translation fault, we have the CPU retry the translation using an AT S1E1R instruction, and inspect PAR_EL1 to determine if the fault was spurious. When PAR_EL1.F == 0, the AT instruction successfully translated the address without a fault, which implies the original fault was spurious. However, in this case we return false and treat the original fault as if it was not spurious. Invert the return value so that we treat such a case as spurious. Cc: Catalin Marinas <catalin.marinas@arm.com> Fixes: 42f91093b043 ("arm64: mm: Ignore spurious translation faults taken from the kernel") Tested-by: James Morse <james.morse@arm.com> Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Will Deacon <will@kernel.org>
2019-10-16arm64: mm: Fix unused variable warning in zone_sizes_initNathan Chancellor1-1/+1
When building arm64 allnoconfig, CONFIG_ZONE_DMA and CONFIG_ZONE_DMA32 get disabled so there is a warning about max_dma being unused. ../arch/arm64/mm/init.c:215:16: warning: unused variable 'max_dma' [-Wunused-variable] unsigned long max_dma = min; ^ 1 warning generated. Add __maybe_unused to make this clear to the compiler. Fixes: 1a8e1cef7603 ("arm64: use both ZONE_DMA and ZONE_DMA32") Reviewed-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2019-10-16arm64/mm: Poison initmem while freeing with free_reserved_area()Anshuman Khandual1-1/+1
Platform implementation for free_initmem() should poison the memory while freeing it up. Hence pass across POISON_FREE_INITMEM while calling into free_reserved_area(). The same is being followed in the generic fallback for free_initmem() and some other platforms overriding it. Cc: Mark Rutland <mark.rutland@arm.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Steven Price <steven.price@arm.com> Acked-by: Will Deacon <will@kernel.org> Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2019-10-16arm64: use generic free_initrd_mem()Mike Rapoport1-12/+0
arm64 calls memblock_free() for the initrd area in its implementation of free_initrd_mem(), but this call has no actual effect that late in the boot process. By the time initrd is freed, all the reserved memory is managed by the page allocator and the memblock.reserved is unused, so the only purpose of the memblock_free() call is to keep track of initrd memory for debugging and accounting. Without the memblock_free() call the only difference between arm64 and the generic versions of free_initrd_mem() is the memory poisoning. Move memblock_free() call to the generic code, enable it there for the architectures that define ARCH_KEEP_MEMBLOCK and use the generic implementation of free_initrd_mem() on arm64. Tested-by: Anshuman Khandual <anshuman.khandual@arm.com> #arm64 Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Acked-by: Will Deacon <will@kernel.org> Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2019-10-14arm64: use both ZONE_DMA and ZONE_DMA32Nicolas Saenz Julienne1-15/+39
So far all arm64 devices have supported 32 bit DMA masks for their peripherals. This is not true anymore for the Raspberry Pi 4 as most of it's peripherals can only address the first GB of memory on a total of up to 4 GB. This goes against ZONE_DMA32's intent, as it's expected for ZONE_DMA32 to be addressable with a 32 bit mask. So it was decided to re-introduce ZONE_DMA in arm64. ZONE_DMA will contain the lower 1G of memory, which is currently the memory area addressable by any peripheral on an arm64 device. ZONE_DMA32 will contain the rest of the 32 bit addressable memory. Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2019-10-14arm64: rename variables used to calculate ZONE_DMA32's sizeNicolas Saenz Julienne1-15/+15
Let the name indicate that they are used to calculate ZONE_DMA32's size as opposed to ZONE_DMA. Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2019-10-14arm64: mm: use arm64_dma_phys_limit instead of calling max_zone_dma_phys()Nicolas Saenz Julienne1-1/+1
By the time we call zones_sizes_init() arm64_dma_phys_limit already contains the result of max_zone_dma_phys(). We use the variable instead of calling the function directly to save some precious cpu time. Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2019-10-07arm64: mm: fix spurious fault detectionMark Rutland1-1/+1
When detecting a spurious EL1 translation fault, we attempt to compare ESR_EL1.DFSC with PAR_EL1.FST. We erroneously use FIELD_PREP() to extract PAR_EL1.FST, when we should be using FIELD_GET(). In the wise words of Robin Murphy: | FIELD_GET() is a UBFX, FIELD_PREP() is a BFI Using FIELD_PREP() means that that dfsc & ESR_ELx_FSC_TYPE is always zero, and hence not equal to ESR_ELx_FSC_FAULT. Thus we detect any unhandled translation fault as spurious. ... so let's use FIELD_GET() to ensure we don't decide all translation faults are spurious. ESR_EL1.DFSC occupies bits [5:0], and requires no shifting. Fixes: 42f91093b043332a ("arm64: mm: Ignore spurious translation faults taken from the kernel") Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reported-by: Robin Murphy <robin.murphy@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Will Deacon <will.deacon@kernel.org> Signed-off-by: Will Deacon <will@kernel.org>
2019-10-04arm64: mm: avoid virt_to_phys(init_mm.pgd)Mark Rutland1-1/+10
If we take an unhandled fault in the kernel, we call show_pte() to dump the {PGDP,PGD,PUD,PMD,PTE} values for the corresponding page table walk, where the PGDP value is virt_to_phys(mm->pgd). The boot-time and runtime kernel page tables, init_pg_dir and swapper_pg_dir respectively, are kernel symbols. Thus, it is not valid to call virt_to_phys() on either of these, though we'll do so if we take a fault on a TTBR1 address. When CONFIG_DEBUG_VIRTUAL is not selected, virt_to_phys() will silently fix this up. However, when CONFIG_DEBUG_VIRTUAL is selected, this results in splats as below. Depending on when these occur, they can happen to suppress information needed to debug the original unhandled fault, such as the backtrace: | Unable to handle kernel paging request at virtual address ffff7fffec73cf0f | Mem abort info: | ESR = 0x96000004 | EC = 0x25: DABT (current EL), IL = 32 bits | SET = 0, FnV = 0 | EA = 0, S1PTW = 0 | Data abort info: | ISV = 0, ISS = 0x00000004 | CM = 0, WnR = 0 | ------------[ cut here ]------------ | virt_to_phys used for non-linear address: 00000000102c9dbe (swapper_pg_dir+0x0/0x1000) | WARNING: CPU: 1 PID: 7558 at arch/arm64/mm/physaddr.c:15 __virt_to_phys+0xe0/0x170 arch/arm64/mm/physaddr.c:12 | Kernel panic - not syncing: panic_on_warn set ... | SMP: stopping secondary CPUs | Dumping ftrace buffer: | (ftrace buffer empty) | Kernel Offset: disabled | CPU features: 0x0002,23000438 | Memory Limit: none | Rebooting in 1 seconds.. We can avoid this by ensuring that we call __pa_symbol() for init_mm.pgd, as this will always be a kernel symbol. As the dumped {PGD,PUD,PMD,PTE} values are the raw values from the relevant entries we don't need to handle these specially. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Cc: James Morse <james.morse@arm.com> Signed-off-by: Will Deacon <will@kernel.org>
2019-09-26mm: treewide: clarify pgtable_page_{ctor,dtor}() namingMark Rutland1-1/+1
The naming of pgtable_page_{ctor,dtor}() seems to have confused a few people, and until recently arm64 used these erroneously/pointlessly for other levels of page table. To make it incredibly clear that these only apply to the PTE level, and to align with the naming of pgtable_pmd_page_{ctor,dtor}(), let's rename them to pgtable_pte_page_{ctor,dtor}(). These changes were generated with the following shell script: ---- git grep -lw 'pgtable_page_.tor' | while read FILE; do sed -i '{s/pgtable_page_ctor/pgtable_pte_page_ctor/}' $FILE; sed -i '{s/pgtable_page_dtor/pgtable_pte_page_dtor/}' $FILE; done ---- ... with the documentation re-flowed to remain under 80 columns, and whitespace fixed up in macros to keep backslashes aligned. There should be no functional change as a result of this patch. Link: http://lkml.kernel.org/r/20190722141133.3116-1-mark.rutland@arm.com Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Mike Rapoport <rppt@linux.ibm.com> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> [m68k] Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Yu Zhao <yuzhao@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-09-24arm64, mm: move generic mmap layout functions to mmAlexandre Ghiti1-76/+0
arm64 handles top-down mmap layout in a way that can be easily reused by other architectures, so make it available in mm. It then introduces a new config ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT that can be set by other architectures to benefit from those functions. Note that this new config depends on MMU being enabled, if selected without MMU support, a warning will be thrown. Link: http://lkml.kernel.org/r/20190730055113.23635-5-alex@ghiti.fr Signed-off-by: Alexandre Ghiti <alex@ghiti.fr> Suggested-by: Christoph Hellwig <hch@infradead.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Kees Cook <keescook@chromium.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Luis Chamberlain <mcgrof@kernel.org> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: James Hogan <jhogan@kernel.org> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Paul Burton <paul.burton@mips.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Russell King <linux@armlinux.org.uk> 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>
2019-09-24arm64: consider stack randomization for mmap base only when necessaryAlexandre Ghiti1-1/+5
Do not offset mmap base address because of stack randomization if current task does not want randomization. Note that x86 already implements this behaviour. Link: http://lkml.kernel.org/r/20190730055113.23635-4-alex@ghiti.fr Signed-off-by: Alexandre Ghiti <alex@ghiti.fr> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Kees Cook <keescook@chromium.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Luis Chamberlain <mcgrof@kernel.org> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@infradead.org> Cc: James Hogan <jhogan@kernel.org> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Paul Burton <paul.burton@mips.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Russell King <linux@armlinux.org.uk> 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>
2019-09-24arm64: make use of is_compat_task instead of hardcoding this testAlexandre Ghiti1-1/+1
Each architecture has its own way to determine if a task is a compat task, by using is_compat_task in arch_mmap_rnd, it allows more genericity and then it prepares its moving to mm/. Link: http://lkml.kernel.org/r/20190730055113.23635-3-alex@ghiti.fr Signed-off-by: Alexandre Ghiti <alex@ghiti.fr> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Kees Cook <keescook@chromium.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Luis Chamberlain <mcgrof@kernel.org> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@infradead.org> Cc: James Hogan <jhogan@kernel.org> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Paul Burton <paul.burton@mips.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Russell King <linux@armlinux.org.uk> 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>
2019-09-24mm: consolidate pgtable_cache_init() and pgd_cache_init()Mike Rapoport1-1/+1
Both pgtable_cache_init() and pgd_cache_init() are used to initialize kmem cache for page table allocations on several architectures that do not use PAGE_SIZE tables for one or more levels of the page table hierarchy. Most architectures do not implement these functions and use __weak default NOP implementation of pgd_cache_init(). Since there is no such default for pgtable_cache_init(), its empty stub is duplicated among most architectures. Rename the definitions of pgd_cache_init() to pgtable_cache_init() and drop empty stubs of pgtable_cache_init(). Link: http://lkml.kernel.org/r/1566457046-22637-1-git-send-email-rppt@linux.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Acked-by: Will Deacon <will@kernel.org> [arm64] Acked-by: Thomas Gleixner <tglx@linutronix.de> [x86] Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Matthew Wilcox <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-09-24mm: introduce page_size()Matthew Wilcox (Oracle)1-2/+1
Patch series "Make working with compound pages easier", v2. These three patches add three helpers and convert the appropriate places to use them. This patch (of 3): It's unnecessarily hard to find out the size of a potentially huge page. Replace 'PAGE_SIZE << compound_order(page)' with page_size(page). Link: http://lkml.kernel.org/r/20190721104612.19120-2-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-09-19Merge tag 'dma-mapping-5.4' of git://git.infradead.org/users/hch/dma-mappingLinus Torvalds1-13/+3
Pull dma-mapping updates from Christoph Hellwig: - add dma-mapping and block layer helpers to take care of IOMMU merging for mmc plus subsequent fixups (Yoshihiro Shimoda) - rework handling of the pgprot bits for remapping (me) - take care of the dma direct infrastructure for swiotlb-xen (me) - improve the dma noncoherent remapping infrastructure (me) - better defaults for ->mmap, ->get_sgtable and ->get_required_mask (me) - cleanup mmaping of coherent DMA allocations (me) - various misc cleanups (Andy Shevchenko, me) * tag 'dma-mapping-5.4' of git://git.infradead.org/users/hch/dma-mapping: (41 commits) mmc: renesas_sdhi_internal_dmac: Add MMC_CAP2_MERGE_CAPABLE mmc: queue: Fix bigger segments usage arm64: use asm-generic/dma-mapping.h swiotlb-xen: merge xen_unmap_single into xen_swiotlb_unmap_page swiotlb-xen: simplify cache maintainance swiotlb-xen: use the same foreign page check everywhere swiotlb-xen: remove xen_swiotlb_dma_mmap and xen_swiotlb_dma_get_sgtable xen: remove the exports for xen_{create,destroy}_contiguous_region xen/arm: remove xen_dma_ops xen/arm: simplify dma_cache_maint xen/arm: use dev_is_dma_coherent xen/arm: consolidate page-coherent.h xen/arm: use dma-noncoherent.h calls for xen-swiotlb cache maintainance arm: remove wrappers for the generic dma remap helpers dma-mapping: introduce a dma_common_find_pages helper dma-mapping: always use VM_DMA_COHERENT for generic DMA remap vmalloc: lift the arm flag for coherent mappings to common code dma-mapping: provide a better default ->get_required_mask dma-mapping: remove the dma_declare_coherent_memory export remoteproc: don't allow modular build ...
2019-09-16Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linuxLinus Torvalds9-55/+117
Pull arm64 updates from Will Deacon: "Although there isn't tonnes of code in terms of line count, there are a fair few headline features which I've noted both in the tag and also in the merge commits when I pulled everything together. The part I'm most pleased with is that we had 35 contributors this time around, which feels like a big jump from the usual small group of core arm64 arch developers. Hopefully they all enjoyed it so much that they'll continue to contribute, but we'll see. It's probably worth highlighting that we've pulled in a branch from the risc-v folks which moves our CPU topology code out to where it can be shared with others. Summary: - 52-bit virtual addressing in the kernel - New ABI to allow tagged user pointers to be dereferenced by syscalls - Early RNG seeding by the bootloader - Improve robustness of SMP boot - Fix TLB invalidation in light of recent architectural clarifications - Support for i.MX8 DDR PMU - Remove direct LSE instruction patching in favour of static keys - Function error injection using kprobes - Support for the PPTT "thread" flag introduced by ACPI 6.3 - Move PSCI idle code into proper cpuidle driver - Relaxation of implicit I/O memory barriers - Build with RELR relocations when toolchain supports them - Numerous cleanups and non-critical fixes" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (114 commits) arm64: remove __iounmap arm64: atomics: Use K constraint when toolchain appears to support it arm64: atomics: Undefine internal macros after use arm64: lse: Make ARM64_LSE_ATOMICS depend on JUMP_LABEL arm64: asm: Kill 'asm/atomic_arch.h' arm64: lse: Remove unused 'alt_lse' assembly macro arm64: atomics: Remove atomic_ll_sc compilation unit arm64: avoid using hard-coded registers for LSE atomics arm64: atomics: avoid out-of-line ll/sc atomics arm64: Use correct ll/sc atomic constraints jump_label: Don't warn on __exit jump entries docs/perf: Add documentation for the i.MX8 DDR PMU perf/imx_ddr: Add support for AXI ID filtering arm64: kpti: ensure patched kernel text is fetched from PoU arm64: fix fixmap copy for 16K pages and 48-bit VA perf/smmuv3: Validate groups for global filtering perf/smmuv3: Validate group size arm64: Relax Documentation/arm64/tagged-pointers.rst arm64: kvm: Replace hardcoded '1' with SYS_PAR_EL1_F arm64: mm: Ignore spurious translation faults taken from the kernel ...
2019-09-11arm64: use asm-generic/dma-mapping.hChristoph Hellwig1-0/+1
Now that the Xen special cases are gone nothing worth mentioning is left in the arm64 <asm/dma-mapping.h> file, so switch to use the asm-generic version instead. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Will Deacon <will@kernel.org> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
2019-09-11xen/arm: remove xen_dma_opsChristoph Hellwig1-1/+2
arm and arm64 can just use xen_swiotlb_dma_ops directly like x86, no need for a pointer indirection. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Julien Grall <julien.grall@arm.com> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
2019-09-04arm64: remove __iounmapChristoph Hellwig1-2/+2
No need to indirect iounmap for arm64. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Will Deacon <will@kernel.org>
2019-08-30Merge branches 'for-next/52-bit-kva', 'for-next/cpu-topology', 'for-next/error-injection', 'for-next/perf', 'for-next/psci-cpuidle', 'for-next/rng', 'for-next/smpboot', 'for-next/tbi' and 'for-next/tlbi' into for-next/coreWill Deacon6-47/+98
* for-next/52-bit-kva: (25 commits) Support for 52-bit virtual addressing in kernel space * for-next/cpu-topology: (9 commits) Move CPU topology parsing into core code and add support for ACPI 6.3 * for-next/error-injection: (2 commits) Support for function error injection via kprobes * for-next/perf: (8 commits) Support for i.MX8 DDR PMU and proper SMMUv3 group validation * for-next/psci-cpuidle: (7 commits) Move PSCI idle code into a new CPUidle driver * for-next/rng: (4 commits) Support for 'rng-seed' property being passed in the devicetree * for-next/smpboot: (3 commits) Reduce fragility of secondary CPU bringup in debug configurations * for-next/tbi: (10 commits) Introduce new syscall ABI with relaxed requirements for pointer tags * for-next/tlbi: (6 commits) Handle spurious page faults arising from kernel space
2019-08-29dma-mapping: make dma_atomic_pool_init self-containedChristoph Hellwig1-6/+0
The memory allocated for the atomic pool needs to have the same mapping attributes that we use for remapping, so use pgprot_dmacoherent instead of open coding it. Also deduct a suitable zone to allocate the memory from based on the presence of the DMA zones. Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-08-29dma-mapping: remove arch_dma_mmap_pgprotChristoph Hellwig1-6/+0
arch_dma_mmap_pgprot is used for two things: 1) to override the "normal" uncached page attributes for mapping memory coherent to devices that can't snoop the CPU caches 2) to provide the special DMA_ATTR_WRITE_COMBINE semantics on older arm systems and some mips platforms Replace one with the pgprot_dmacoherent macro that is already provided by arm and much simpler to use, and lift the DMA_ATTR_WRITE_COMBINE handling to common code with an explicit arch opt-in. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> # m68k Acked-by: Paul Burton <paul.burton@mips.com> # mips
2019-08-28arm64: kpti: ensure patched kernel text is fetched from PoUMark Rutland1-0/+9
While the MMUs is disabled, I-cache speculation can result in instructions being fetched from the PoC. During boot we may patch instructions (e.g. for alternatives and jump labels), and these may be dirty at the PoU (and stale at the PoC). Thus, while the MMU is disabled in the KPTI pagetable fixup code we may load stale instructions into the I-cache, potentially leading to subsequent crashes when executing regions of code which have been modified at runtime. Similarly to commit: 8ec41987436d566f ("arm64: mm: ensure patched kernel text is fetched from PoU") ... we can invalidate the I-cache after enabling the MMU to prevent such issues. The KPTI pagetable fixup code itself should be clean to the PoC per the boot protocol, so no maintenance is required for this code. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: James Morse <james.morse@arm.com> Signed-off-by: Will Deacon <will@kernel.org>
2019-08-28arm64: fix fixmap copy for 16K pages and 48-bit VAMark Rutland1-3/+5
With 16K pages and 48-bit VAs, the PGD level of table has two entries, and so the fixmap shares a PGD with the kernel image. Since commit: f9040773b7bbbd9e ("arm64: move kernel image to base of vmalloc area") ... we copy the existing fixmap to the new fine-grained page tables at the PUD level in this case. When walking to the new PUD, we forgot to offset the PGD entry and always used the PGD entry at index 0, but this worked as the kernel image and fixmap were in the low half of the TTBR1 address space. As of commit: 14c127c957c1c607 ("arm64: mm: Flip kernel VA space") ... the kernel image and fixmap are in the high half of the TTBR1 address space, and hence use the PGD at index 1, but we didn't update the fixmap copying code to account for this. Thus, we'll erroneously try to copy the fixmap slots into a PUD under the PGD entry at index 0. At the point we do so this PGD entry has not been initialised, and thus we'll try to write a value to a small offset from physical address 0, causing a number of potential problems. Fix this be correctly offsetting the PGD. This is split over a few steps for legibility. Fixes: 14c127c957c1c607 ("arm64: mm: Flip kernel VA space") Reported-by: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Marc Zyngier <maz@kernel.org> Tested-by: Marc Zyngier <maz@kernel.org> Acked-by: Steve Capper <Steve.Capper@arm.com> Tested-by: Steve Capper <Steve.Capper@arm.com> Tested-by: Anshuman Khandual <anshuman.khandual@arm.com> Signed-off-by: Will Deacon <will@kernel.org>
2019-08-27arm64: mm: Ignore spurious translation faults taken from the kernelWill Deacon1-0/+33
Thanks to address translation being performed out of order with respect to loads and stores, it is possible for a CPU to take a translation fault when accessing a page that was mapped by a different CPU. For example, in the case that one CPU maps a page and then sets a flag to tell another CPU: CPU 0 ----- MOV X0, <valid pte> STR X0, [Xptep] // Store new PTE to page table DSB ISHST ISB MOV X1, #1 STR X1, [Xflag] // Set the flag CPU 1 ----- loop: LDAR X0, [Xflag] // Poll flag with Acquire semantics CBZ X0, loop LDR X1, [X2] // Translates using the new PTE then the final load on CPU 1 can raise a translation fault because the translation can be performed speculatively before the read of the flag and marked as "faulting" by the CPU. This isn't quite as bad as it sounds since, in reality, code such as: CPU 0 CPU 1 ----- ----- spin_lock(&lock); spin_lock(&lock); *ptr = vmalloc(size); if (*ptr) spin_unlock(&lock); foo = **ptr; spin_unlock(&lock); will not trigger the fault because there is an address dependency on CPU 1 which prevents the speculative translation. However, more exotic code where the virtual address is known ahead of time, such as: CPU 0 CPU 1 ----- ----- spin_lock(&lock); spin_lock(&lock); set_fixmap(0, paddr, prot); if (mapped) mapped = true; foo = *fix_to_virt(0); spin_unlock(&lock); spin_unlock(&lock); could fault. This can be avoided by any of: * Introducing broadcast TLB maintenance on the map path * Adding a DSB;ISB sequence after checking a flag which indicates that a virtual address is now mapped * Handling the spurious fault Given that we have never observed a problem due to this under Linux and future revisions of the architecture are being tightened so that translation table walks are effectively ordered in the same way as explicit memory accesses, we no longer treat spurious kernel faults as fatal if an AT instruction indicates that the access does not trigger a translation fault. Reviewed-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Will Deacon <will@kernel.org>
2019-08-23arm64: map FDT as RW for early_init_dt_scan()Hsin-Yi Wang1-14/+1
Currently in arm64, FDT is mapped to RO before it's passed to early_init_dt_scan(). However, there might be some codes (eg. commit "fdt: add support for rng-seed") that need to modify FDT during init. Map FDT to RO after early fixups are done. Signed-off-by: Hsin-Yi Wang <hsinyi@chromium.org> Reviewed-by: Stephen Boyd <swboyd@chromium.org> Reviewed-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Will Deacon <will@kernel.org>
2019-08-15arm64: unexport set_memory_x and set_memory_nxChristoph Hellwig1-2/+0
No module currently messed with clearing or setting the execute permission of kernel memory, and none really should. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Will Deacon <will@kernel.org>
2019-08-14arm64: memory: rename VA_START to PAGE_ENDMark Rutland3-6/+6
Prior to commit: 14c127c957c1c607 ("arm64: mm: Flip kernel VA space") ... VA_START described the start of the TTBR1 address space for a given VA size described by VA_BITS, where all kernel mappings began. Since that commit, VA_START described a portion midway through the address space, where the linear map ends and other kernel mappings begin. To avoid confusion, let's rename VA_START to PAGE_END, making it clear that it's not the start of the TTBR1 address space and implying that it's related to PAGE_OFFSET. Comments and other mnemonics are updated accordingly, along with a typo fix in the decription of VMEMMAP_SIZE. There should be no functional change as a result of this patch. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Tested-by: Steve Capper <steve.capper@arm.com> Reviewed-by: Steve Capper <steve.capper@arm.com> Signed-off-by: Will Deacon <will@kernel.org>
2019-08-14arm64: memory: fix flipped VA space falloutMark Rutland2-2/+2
VA_START used to be the start of the TTBR1 address space, but now it's a point midway though. In a couple of places we still use VA_START to get the start of the TTBR1 address space, so let's fix these up to use PAGE_OFFSET instead. Fixes: 14c127c957c1c607 ("arm64: mm: Flip kernel VA space") Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Tested-by: Steve Capper <steve.capper@arm.com> Reviewed-by: Steve Capper <steve.capper@arm.com> Signed-off-by: Will Deacon <will@kernel.org>
2019-08-10dma-mapping: fix page attributes for dma_mmap_*Christoph Hellwig1-3/+1
All the way back to introducing dma_common_mmap we've defaulted to mark the pages as uncached. But this is wrong for DMA coherent devices. Later on DMA_ATTR_WRITE_COMBINE also got incorrect treatment as that flag is only treated special on the alloc side for non-coherent devices. Introduce a new dma_pgprot helper that deals with the check for coherent devices so that only the remapping cases ever reach arch_dma_mmap_pgprot and we thus ensure no aliasing of page attributes happens, which makes the powerpc version of arch_dma_mmap_pgprot obsolete and simplifies the remaining ones. Note that this means arch_dma_mmap_pgprot is a bit misnamed now, but we'll phase it out soon. Fixes: 64ccc9c033c6 ("common: dma-mapping: add support for generic dma_mmap_* calls") Reported-by: Shawn Anastasio <shawn@anastas.io> Reported-by: Gavin Li <git@thegavinli.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Catalin Marinas <catalin.marinas@arm.com> # arm64
2019-08-09arm64: mm: Remove vabits_userSteve Capper3-5/+2
Previous patches have enabled 52-bit kernel + user VAs and there is no longer any scenario where user VA != kernel VA size. This patch removes the, now redundant, vabits_user variable and replaces usage with vabits_actual where appropriate. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Steve Capper <steve.capper@arm.com> Signed-off-by: Will Deacon <will@kernel.org>