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2018-07-05arm64: IPI each CPU after invalidating the I-cache for kernel mappingsWill Deacon1-1/+26
When invalidating the instruction cache for a kernel mapping via flush_icache_range(), it is also necessary to flush the pipeline for other CPUs so that instructions fetched into the pipeline before the I-cache invalidation are discarded. For example, if module 'foo' is unloaded and then module 'bar' is loaded into the same area of memory, a CPU could end up executing instructions from 'foo' when branching into 'bar' if these instructions were fetched into the pipeline before 'foo' was unloaded. Whilst this is highly unlikely to occur in practice, particularly as any exception acts as a context-synchronizing operation, following the letter of the architecture requires us to execute an ISB on each CPU in order for the new instruction stream to be visible. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-06-15docs: Fix some broken referencesMauro Carvalho Chehab1-1/+1
As we move stuff around, some doc references are broken. Fix some of them via this script: ./scripts/documentation-file-ref-check --fix Manually checked if the produced result is valid, removing a few false-positives. Acked-by: Takashi Iwai <tiwai@suse.de> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Acked-by: Stephen Boyd <sboyd@kernel.org> Acked-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com> Acked-by: Mathieu Poirier <mathieu.poirier@linaro.org> Reviewed-by: Coly Li <colyli@suse.de> Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Acked-by: Jonathan Corbet <corbet@lwn.net>
2018-04-11arm64: turn flush_dcache_mmap_lock into a no-opMatthew Wilcox1-4/+2
ARM64 doesn't walk the VMA tree in its flush_dcache_page() implementation, so has no need to take the tree_lock. Link: http://lkml.kernel.org/r/20180313132639.17387-4-willy@infradead.org Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com> Reviewed-by: Will Deacon <will.deacon@arm.com> Cc: Darrick J. Wong <darrick.wong@oracle.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Jeff Layton <jlayton@kernel.org> Cc: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-03-09arm64: Add support for new control bits CTR_EL0.DIC and CTR_EL0.IDCShanker Donthineni1-0/+3
The DCache clean & ICache invalidation requirements for instructions to be data coherence are discoverable through new fields in CTR_EL0. The following two control bits DIC and IDC were defined for this purpose. No need to perform point of unification cache maintenance operations from software on systems where CPU caches are transparent. This patch optimize the three functions __flush_cache_user_range(), clean_dcache_area_pou() and invalidate_icache_range() if the hardware reports CTR_EL0.IDC and/or CTR_EL0.IDC. Basically it skips the two instructions 'DC CVAU' and 'IC IVAU', and the associated loop logic in order to avoid the unnecessary overhead. CTR_EL0.DIC: Instruction cache invalidation requirements for instruction to data coherence. The meaning of this bit[29]. 0: Instruction cache invalidation to the point of unification is required for instruction to data coherence. 1: Instruction cache cleaning to the point of unification is not required for instruction to data coherence. CTR_EL0.IDC: Data cache clean requirements for instruction to data coherence. The meaning of this bit[28]. 0: Data cache clean to the point of unification is required for instruction to data coherence, unless CLIDR_EL1.LoC == 0b000 or (CLIDR_EL1.LoUIS == 0b000 && CLIDR_EL1.LoUU == 0b000). 1: Data cache clean to the point of unification is not required for instruction to data coherence. Co-authored-by: Philip Elcan <pelcan@codeaurora.org> Reviewed-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Shanker Donthineni <shankerd@codeaurora.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-01-08arm64: KVM: Add invalidate_icache_range helperMarc Zyngier1-0/+7
We currently tightly couple dcache clean with icache invalidation, but KVM could do without the initial flush to PoU, as we've already flushed things to PoC. Let's introduce invalidate_icache_range which is limited to invalidating the icache from the linear mapping (and thus has none of the userspace fault handling complexity), and wire it in KVM instead of flush_icache_range. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-11-28arm64: mm: cleanup stale AIVIVT referencesMark Rutland1-1/+1
Since commit: 155433cb365ee466 ("arm64: cache: Remove support for ASID-tagged VIVT I-caches") ... the kernel no longer cares about AIVIVT I-caches, as these were removed from the architecture. This patch removes the stale references to such I-caches. The comment in flush_context() is also updated to clarify when and where the TLB invalidation occurs. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-08-09arm64: Implement pmem API supportRobin Murphy1-0/+1
Add a clean-to-point-of-persistence cache maintenance helper, and wire up the basic architectural support for the pmem driver based on it. Reviewed-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Robin Murphy <robin.murphy@arm.com> [catalin.marinas@arm.com: move arch_*_pmem() functions to arch/arm64/mm/flush.c] [catalin.marinas@arm.com: change dmb(sy) to dmb(osh)] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-08-09arm64: Convert __inval_cache_range() to area-basedRobin Murphy1-0/+1
__inval_cache_range() is already the odd one out among our data cache maintenance routines as the only remaining range-based one; as we're going to want an invalidation routine to call from C code for the pmem API, let's tweak the prototype and name to bring it in line with the clean operations, and to make its relationship with __dma_inv_area() neatly mirror that of __clean_dcache_area_poc() and __dma_clean_area(). The loop clearing the early page tables gets mildly massaged in the process for the sake of consistency. Reviewed-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-08-09arm64: mm: Fix set_memory_valid() declarationRobin Murphy1-1/+1
Clearly, set_memory_valid() has never been seen in the same room as its declaration... Whilst the type mismatch is such that kexec probably wasn't broken in practice, fix it to match the definition as it should. Fixes: 9b0aa14e3155 ("arm64: mm: add set_memory_valid()") Reviewed-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-05-08treewide: decouple cacheflush.h and set_memory.hLaura Abbott1-1/+0
Now that all call sites, completely decouple cacheflush.h and set_memory.h [sfr@canb.auug.org.au: kprobes/x86: merge fix for set_memory.h decoupling] Link: http://lkml.kernel.org/r/20170418180903.10300fd3@canb.auug.org.au Link: http://lkml.kernel.org/r/1488920133-27229-17-git-send-email-labbott@redhat.com Signed-off-by: Laura Abbott <labbott@redhat.com> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-05-08treewide: move set_memory_* functions away from cacheflush.hLaura Abbott1-4/+1
Patch series "set_memory_* functions header refactor", v3. The set_memory_* APIs came out of a desire to have a better way to change memory attributes. Many of these attributes were linked to cache functionality so the prototypes were put in cacheflush.h. These days, the APIs have grown and have a much wider use than just cache APIs. To support this growth, split off set_memory_* and friends into a separate header file to avoid growing cacheflush.h for APIs that have nothing to do with caches. Link: http://lkml.kernel.org/r/1488920133-27229-2-git-send-email-labbott@redhat.com Signed-off-by: Laura Abbott <labbott@redhat.com> Acked-by: Russell King <rmk+kernel@armlinux.org.uk> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-04-05arm64: mm: add set_memory_valid()AKASHI Takahiro1-0/+1
This function validates and invalidates PTE entries, and will be utilized in kdump to protect loaded crash dump kernel image. Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-11-23arm64: Remove I-cache invalidation from flush_cache_range()Catalin Marinas1-1/+5
The flush_cache_range() function (similarly for flush_cache_page()) is called when the kernel is changing an existing VA->PA mapping range to either a new PA or to different attributes. Since ARMv8 has PIPT-like D-caches, this function does not need to perform any D-cache maintenance. The I-cache maintenance is already handled via set_pte_at() and flush_cache_range() cannot anyway guarantee that there are no cache lines left after invalidation due to the speculative loads. This patch makes flush_cache_range() a no-op. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-11-07arm64: Add uprobe supportPratyush Anand1-0/+1
This patch adds support for uprobe on ARM64 architecture. Unit tests for following have been done so far and they have been found working 1. Step-able instructions, like sub, ldr, add etc. 2. Simulation-able like ret, cbnz, cbz etc. 3. uretprobe 4. Reject-able instructions like sev, wfe etc. 5. trapped and abort xol path 6. probe at unaligned user address. 7. longjump test cases Currently it does not support aarch32 instruction probing. Signed-off-by: Pratyush Anand <panand@redhat.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-08-22arm64: mm: convert __dma_* routines to use start, sizeKwangwoo Lee1-1/+2
__dma_* routines have been converted to use start and size instread of start and end addresses. The patch was origianlly for adding __clean_dcache_area_poc() which will be used in pmem driver to clean dcache to the PoC(Point of Coherency) in arch_wb_cache_pmem(). The functionality of __clean_dcache_area_poc() was equivalent to __dma_clean_range(). The difference was __dma_clean_range() uses the end address, but __clean_dcache_area_poc() uses the size to clean. Thus, __clean_dcache_area_poc() has been revised with a fallthrough function of __dma_clean_range() after the change that __dma_* routines use start and size instead of using start and end. As a consequence of using start and size, the name of __dma_* routines has also been altered following the terminology below: area: takes a start and size range: takes a start and end Reviewed-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Kwangwoo Lee <kwangwoo.lee@sk.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-03-24Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linuxLinus Torvalds1-7/+0
Pull second set of arm64 updates from Catalin Marinas: - KASLR bug fixes: use callee-saved register, boot-time I-cache maintenance - inv_entry asm macro fix (EL0 check typo) - pr_notice("Virtual kernel memory layout...") splitting - Clean-ups: use p?d_set_huge consistently, allow preemption around copy_to_user_page, remove unused __local_flush_icache_all() * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64: mm: allow preemption in copy_to_user_page arm64: consistently use p?d_set_huge arm64: kaslr: use callee saved register to preserve SCTLR across C call arm64: Split pr_notice("Virtual kernel memory layout...") into multiple pr_cont() arm64: drop unused __local_flush_icache_all() arm64: fix KASLR boot-time I-cache maintenance arm64/kernel: fix incorrect EL0 check in inv_entry macro
2016-03-21arm64: drop unused __local_flush_icache_all()Kefeng Wang1-7/+0
After commit 65da0a8e34a8 ("arm64: use non-global mappings for UEFI runtime regions"), nobody use __local_flush_icache_all() anymore, so drop it. Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-02-22asm-generic: Consolidate mark_rodata_ro()Kees Cook1-4/+0
Instead of defining mark_rodata_ro() in each architecture, consolidate it. Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Will Deacon <will.deacon@arm.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Gross <agross@codeaurora.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Ashok Kumar <ashoks@broadcom.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Borislav Petkov <bp@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: David Brown <david.brown@linaro.org> Cc: David Hildenbrand <dahi@linux.vnet.ibm.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Emese Revfy <re.emese@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Helge Deller <deller@gmx.de> Cc: James E.J. Bottomley <jejb@parisc-linux.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathias Krause <minipli@googlemail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nicolas Pitre <nicolas.pitre@linaro.org> Cc: PaX Team <pageexec@freemail.hu> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Toshi Kani <toshi.kani@hp.com> Cc: kernel-hardening@lists.openwall.com Cc: linux-arch <linux-arch@vger.kernel.org> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Cc: linux-parisc@vger.kernel.org Link: http://lkml.kernel.org/r/1455748879-21872-2-git-send-email-keescook@chromium.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-12-17arm64: Use PoU cache instr for I/D coherencyAshok Kumar1-0/+1
In systems with three levels of cache(PoU at L1 and PoC at L3), PoC cache flush instructions flushes L2 and L3 caches which could affect performance. For cache flushes for I and D coherency, PoU should suffice. So changing all I and D coherency related cache flushes to PoU. Introduced a new __clean_dcache_area_pou API for dcache flush till PoU and provided a common macro for __flush_dcache_area and __clean_dcache_area_pou. Also, now in __sync_icache_dcache, icache invalidation for non-aliasing VIPT icache is done only for that particular page instead of the earlier __flush_icache_all. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Ashok Kumar <ashoks@broadcom.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-10-07arm64: flush: use local TLB and I-cache invalidationWill Deacon1-0/+7
There are a number of places where a single CPU is running with a private page-table and we need to perform maintenance on the TLB and I-cache in order to ensure correctness, but do not require the operation to be broadcast to other CPUs. This patch adds local variants of tlb_flush_all and __flush_icache_all to support these use-cases and updates the callers respectively. __local_flush_icache_all also implies an isb, since it is intended to be used synchronously. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: David Daney <david.daney@cavium.com> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-05-19arm64: kill flush_cache_all()Mark Rutland1-5/+0
The documented semantics of flush_cache_all are not possible to provide for arm64 (short of flushing the entire physical address space by VA), and there are currently no users; KVM uses VA maintenance exclusively, cpu_reset is never called, and the only two users outside of arch code cannot be built for arm64. While cpu_soft_reset and related functions (which call flush_cache_all) were thought to be useful for kexec, their current implementations only serve to mask bugs. For correctness kexec will need to perform maintenance by VA anyway to account for system caches, line migration, and other subtleties of the cache architecture. As the extent of this cache maintenance will be kexec-specific, it should probably live in the kexec code. This patch removes flush_cache_all, and related unused components, preventing further abuse. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Geoff Levand <geoff@infradead.org> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-01-22arm64: add better page protections to arm64Laura Abbott1-0/+5
Add page protections for arm64 similar to those in arm. This is for security reasons to prevent certain classes of exploits. The current method: - Map all memory as either RWX or RW. We round to the nearest section to avoid creating page tables before everything is mapped - Once everything is mapped, if either end of the RWX section should not be X, we split the PMD and remap as necessary - When initmem is to be freed, we change the permissions back to RW (using stop machine if necessary to flush the TLB) - If CONFIG_DEBUG_RODATA is set, the read only sections are set read only. Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Tested-by: Kees Cook <keescook@chromium.org> Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Laura Abbott <lauraa@codeaurora.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-12-01arm64: compat: align cacheflush syscall with arch/armVladimir Murzin1-1/+1
Update handling of cacheflush syscall with changes made in arch/arm counterpart: - return error to userspace when flushing syscall fails - split user cache-flushing into interruptible chunks - don't bother rounding to nearest vma Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> [will: changed internal return value from -EINTR to 0 to match arch/arm/] Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-09-08arm64: Add CONFIG_DEBUG_SET_MODULE_RONX supportLaura Abbott1-0/+4
In a similar fashion to other architecture, add the infrastructure and Kconfig to enable DEBUG_SET_MODULE_RONX support. When enabled, module ranges will be marked read-only/no-execute as appropriate. Signed-off-by: Laura Abbott <lauraa@codeaurora.org> [will: fixed off-by-one in module end check] Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-07-24arm64: Fix barriers used for page table modificationsCatalin Marinas1-10/+1
The architecture specification states that both DSB and ISB are required between page table modifications and subsequent memory accesses using the corresponding virtual address. When TLB invalidation takes place, the tlb_flush_* functions already have the necessary barriers. However, there are other functions like create_mapping() for which this is not the case. The patch adds the DSB+ISB instructions in the set_pte() function for valid kernel mappings. The invalid pte case is handled by tlb_flush_* and the user mappings in general have a corresponding update_mmu_cache() call containing a DSB. Even when update_mmu_cache() isn't called, the kernel can still cope with an unlikely spurious page fault by re-executing the instruction. In addition, the set_pmd, set_pud() functions gain an ISB for architecture compliance when block mappings are created. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Reported-by: Leif Lindholm <leif.lindholm@linaro.org> Acked-by: Steve Capper <steve.capper@linaro.org> Cc: Will Deacon <will.deacon@arm.com> Cc: <stable@vger.kernel.org>
2014-05-09arm64: barriers: make use of barrier options with explicit barriersWill Deacon1-2/+2
When calling our low-level barrier macros directly, we can often suffice with more relaxed behaviour than the default "all accesses, full system" option. This patch updates the users of dsb() to specify the option which they actually require. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-02-27arm64: Implement coherent DMA API based on swiotlbCatalin Marinas1-0/+7
This patch adds support for DMA API cache maintenance on SoCs without hardware device cache coherency. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-02-05arm64: add DSB after icache flush in __flush_icache_all()Vinayak Kale1-0/+1
Add DSB after icache flush to complete the cache maintenance operation. The function __flush_icache_all() is used only for user space mappings and an ISB is not required because of an exception return before executing user instructions. An exception return would behave like an ISB. Signed-off-by: Vinayak Kale <vkale@apm.com> Acked-by: Will Deacon <will.deacon@arm.com> Cc: <stable@vger.kernel.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2013-06-07arm64: Remove __flush_dcache_page()Catalin Marinas1-3/+0
This function is only used in __sync_icache_dcache(), so remove it and call __flush_dcache_area() directly. The flush_icache_user_range() function is not used in the arm64 kernel. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Reported-by: Will Deacon <will.deacon@arm.com> Acked-by: Will Deacon <will.deacon@arm.com>
2012-11-23arm64: Convert empty flush_cache_{mm,page} functions to static inlineCatalin Marinas1-2/+9
These functions are empty, just make them static inline in the header. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2012-09-17arm64: Cache maintenance routinesCatalin Marinas1-0/+148
The patch adds functionality required for cache maintenance. The AArch64 architecture mandates non-aliasing VIPT or PIPT D-cache and VIPT (may have aliases) or ASID-tagged VIVT I-cache. Cache maintenance operations are automatically broadcast in hardware between CPUs. Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Tony Lindgren <tony@atomide.com> Acked-by: Nicolas Pitre <nico@linaro.org> Acked-by: Olof Johansson <olof@lixom.net> Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Acked-by: Arnd Bergmann <arnd@arndb.de>