kernel.git/arch/arm64/include, branch linux-4.18.y

arm64: jump_label.h: use asm_volatile_goto macro instead of "asm goto"

2018-10-10T06:56:03Z

[ Upstream commit 13aceef06adfaf93d52e01e28a8bc8a0ad471d83 ] All other uses of "asm goto" go through asm_volatile_goto, which avoids a miscompile when using GCC < 4.8.2. Replace our open-coded "asm goto" statements with the asm_volatile_goto macro to avoid issues with older toolchains. Cc: Catalin Marinas Reviewed-by: Nick Desaulniers Signed-off-by: Miguel Ojeda Signed-off-by: Will Deacon Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

arm64: Handle mismatched cache type

2018-09-05T07:29:43Z

commit 314d53d297980676011e6fd83dac60db4a01dc70 upstream. Track mismatches in the cache type register (CTR_EL0), other than the D/I min line sizes and trap user accesses if there are any. Fixes: be68a8aaf925 ("arm64: cpufeature: Fix CTR_EL0 field definitions") Cc: Cc: Mark Rutland Cc: Will Deacon Cc: Catalin Marinas Signed-off-by: Suzuki K Poulose Signed-off-by: Will Deacon Signed-off-by: Greg Kroah-Hartman

arm64: Fix mismatched cache line size detection

2018-09-05T07:29:43Z

commit 4c4a39dd5fe2d13e2d2fa5fceb8ef95d19fc389a upstream. If there is a mismatch in the I/D min line size, we must always use the system wide safe value both in applications and in the kernel, while performing cache operations. However, we have been checking more bits than just the min line sizes, which triggers false negatives. We may need to trap the user accesses in such cases, but not necessarily patch the kernel. This patch fixes the check to do the right thing as advertised. A new capability will be added to check mismatches in other fields and ensure we trap the CTR accesses. Fixes: be68a8aaf925 ("arm64: cpufeature: Fix CTR_EL0 field definitions") Cc: Cc: Mark Rutland Cc: Catalin Marinas Reported-by: Will Deacon Signed-off-by: Suzuki K Poulose Signed-off-by: Will Deacon Signed-off-by: Greg Kroah-Hartman

mm: do not initialize TLB stack vma's with vma_init()

2018-08-01T20:43:38Z

Commit 2c4541e24c55 ("mm: use vma_init() to initialize VMAs on stack and data segments") tried to initialize various left-over ad-hoc vma's "properly", but actually made things worse for the temporary vma's used for TLB flushing. vma_init() doesn't actually initialize all of the vma, just a few fields, so doing something like - struct vm_area_struct vma = { .vm_mm = tlb->mm, }; + struct vm_area_struct vma; + + vma_init(&vma, tlb->mm); was actually very bad: instead of having a nicely initialized vma with every field but "vm_mm" zeroed, you'd have an entirely uninitialized vma with only a couple of fields initialized. And they weren't even fields that the code in question mostly cared about. The flush_tlb_range() function takes a "struct vma" rather than a "struct mm_struct", because a few architectures actually care about what kind of range it is - being able to only do an ITLB flush if it's a range that doesn't have data accesses enabled, for example. And all the normal users already have the vma for doing the range invalidation. But a few people want to call flush_tlb_range() with a range they just made up, so they also end up using a made-up vma. x86 just has a special "flush_tlb_mm_range()" function for this, but other architectures (arm and ia64) do the "use fake vma" thing instead, and thus got caught up in the vma_init() changes. At the same time, the TLB flushing code really doesn't care about most other fields in the vma, so vma_init() is just unnecessary and pointless. This fixes things by having an explicit "this is just an initializer for the TLB flush" initializer macro, which is used by the arm/arm64/ia64 people who mis-use this interface with just a dummy vma. Fixes: 2c4541e24c55 ("mm: use vma_init() to initialize VMAs on stack and data segments") Cc: Dmitry Vyukov Cc: Oleg Nesterov Cc: Andrea Arcangeli Cc: Kirill Shutemov Cc: Andrew Morton Cc: John Stultz Cc: Hugh Dickins Signed-off-by: Linus Torvalds

mm: use vma_init() to initialize VMAs on stack and data segments

2018-07-27T02:38:03Z

Make sure to initialize all VMAs properly, not only those which come from vm_area_cachep. Link: http://lkml.kernel.org/r/20180724121139.62570-3-kirill.shutemov@linux.intel.com Signed-off-by: Kirill A. Shutemov Acked-by: Linus Torvalds Reviewed-by: Andrew Morton Cc: Dmitry Vyukov Cc: Oleg Nesterov Cc: Andrea Arcangeli Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

arm64: neon: Fix function may_use_simd() return error status

2018-07-11T16:02:02Z

It does not matter if the caller of may_use_simd() migrates to another cpu after the call, but it is still important that the kernel_neon_busy percpu instance that is read matches the cpu the task is running on at the time of the read. This means that raw_cpu_read() is not sufficient. kernel_neon_busy may appear true if the caller migrates during the execution of raw_cpu_read() and the next task to be scheduled in on the initial cpu calls kernel_neon_begin(). This patch replaces raw_cpu_read() with this_cpu_read() to protect against this race. Cc: Fixes: cb84d11e1625 ("arm64: neon: Remove support for nested or hardirq kernel-mode NEON") Acked-by: Ard Biesheuvel Reviewed-by: Dave Martin Reviewed-by: Mark Rutland Signed-off-by: Yandong Zhao Signed-off-by: Will Deacon

arm64: Remove unnecessary ISBs from set_{pte,pmd,pud}

2018-06-27T17:26:20Z

Commit 7f0b1bf04511 ("arm64: Fix barriers used for page table modifications") fixed a reported issue with fixmap page-table entries not being visible to the walker due to a missing DSB instruction. At the same time, it added ISB instructions to the arm64 set_{pte,pmd,pud} functions, which are not required by the architecture and make little sense in isolation. Remove the redundant ISBs. Acked-by: Catalin Marinas Acked-by: Mark Rutland Signed-off-by: Will Deacon Signed-off-by: Catalin Marinas

arm64: Avoid flush_icache_range() in alternatives patching code

2018-06-27T17:21:53Z

The implementation of flush_icache_range() includes instruction sequences which are themselves patched at runtime, so it is not safe to call from the patching framework. This patch reworks the alternatives cache-flushing code so that it rolls its own internal D-cache maintenance using DC CIVAC before invalidating the entire I-cache after all alternatives have been applied at boot. Modules don't cause any issues, since flush_icache_range() is safe to call by the time they are loaded. Acked-by: Mark Rutland Reported-by: Rohit Khanna Cc: Alexander Van Brunt Signed-off-by: Will Deacon Signed-off-by: Catalin Marinas

KVM: arm64/sve: Fix SVE trap restoration for non-current tasks

2018-06-21T08:14:44Z

Commit e6b673b ("KVM: arm64: Optimise FPSIMD handling to reduce guest/host thrashing") attempts to restore the configuration of userspace SVE trapping via a call to fpsimd_bind_task_to_cpu(), but the logic for determining when to do this is not correct. The patch makes the errnoenous assumption that the only task that may try to enter userspace with the currently loaded FPSIMD/SVE register content is current. This may not be the case however: if some other user task T is scheduled on the CPU during the execution of the KVM run loop, and the vcpu does not try to use the registers in the meantime, then T's state may be left there intact. If T happens to be the next task to enter userspace on this CPU then the hooks for reloading the register state and configuring traps will be skipped. (Also, current never has SVE state at this point anyway and should always have the trap enabled, as a side-effect of the ioctl() syscall needed to reach the KVM run loop in the first place.) This patch instead restores the state of the EL0 trap from the state observed at the most recent vcpu_load(), ensuring that the trap is set correctly for the loaded context (if any). Fixes: e6b673b741ea ("KVM: arm64: Optimise FPSIMD handling to reduce guest/host thrashing") Signed-off-by: Dave Martin Signed-off-by: Marc Zyngier

arm64: Introduce sysreg_clear_set()

2018-06-21T08:14:54Z

Currently we have a couple of helpers to manipulate bits in particular sysregs: * config_sctlr_el1(u32 clear, u32 set) * change_cpacr(u64 val, u64 mask) The parameters of these differ in naming convention, order, and size, which is unfortunate. They also differ slightly in behaviour, as change_cpacr() skips the sysreg write if the bits are unchanged, which is a useful optimization when sysreg writes are expensive. Before we gain yet another sysreg manipulation function, let's unify these with a common helper, providing a consistent order for clear/set operands, and the write skipping behaviour from change_cpacr(). Code will be migrated to the new helper in subsequent patches. Signed-off-by: Mark Rutland Reviewed-by: Dave Martin Acked-by: Catalin Marinas Signed-off-by: Marc Zyngier