- 17 5月, 2014 6 次提交
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由 Arun KS 提交于
If one process calls sys_reboot and that process then stops other CPUs while those CPUs are within a spin_lock() region we can potentially encounter a deadlock scenario like below. CPU 0 CPU 1 ----- ----- spin_lock(my_lock) smp_send_stop() <send IPI> handle_IPI() disable_preemption/irqs while(1); <PREEMPT> spin_lock(my_lock) <--- Waits forever We shouldn't attempt to run any other tasks after we send a stop IPI to a CPU so disable preemption so that this task runs to completion. We use local_irq_disable() here for cross-arch consistency with x86. Based-on-work-by: NStephen Boyd <sboyd@codeaurora.org> Signed-off-by: NArun KS <getarunks@gmail.com> Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
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由 Arun KS 提交于
This patch ports most of commit 19ab428f "ARM: 7759/1: decouple CPU offlining from reboot/shutdown" by Stephen Warren from arch/arm to arch/arm64. machine_shutdown() is a hook for kexec. Add a comment saying so, since it isn't obvious from the function name. Halt, power-off, and restart have different requirements re: stopping secondary CPUs than kexec has. The former simply require the secondary CPUs to be quiesced somehow, whereas kexec requires them to be completely non-operational, so that no matter where the kexec target images are written in RAM, they won't influence operation of the secondary CPUS,which could happen if the CPUs were still executing some kind of pin loop. To this end, modify machine_halt, power_off, and restart to call smp_send_stop() directly, rather than calling machine_shutdown(). In machine_shutdown(), replace the call to smp_send_stop() with a call to disable_nonboot_cpus(). This completely disables all but one CPU, thus satisfying the kexec requirements a couple paragraphs above. Signed-off-by: NArun KS <getarunks@gmail.com> Acked-by: NStephen Warren <swarren@nvidia.com> Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
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由 Larry Bassel 提交于
Support for arch_irq_work_raise() was missing from arm64 (a prerequisite for FULL_NOHZ). This patch is based on the arm32 patch ARM 7872/1. commit bf18525f Author: Stephen Boyd <sboyd@codeaurora.org> Date: Tue Oct 29 20:32:56 2013 +0100 ARM: 7872/1: Support arch_irq_work_raise() via self IPIs By default, IRQ work is run from the tick interrupt (see irq_work_run() in update_process_times()). When we're in full NOHZ mode, restarting the tick requires the use of IRQ work and if the only place we run IRQ work is in the tick interrupt we have an unbreakable cycle. Implement arch_irq_work_raise() via self IPIs to break this cycle and get the tick started again. Note that we implement this via IPIs which are only available on SMP builds. This shouldn't be a problem because full NOHZ is only supported on SMP builds anyway. Signed-off-by: NStephen Boyd <sboyd@codeaurora.org> Reviewed-by: NKevin Hilman <khilman@linaro.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: NLarry Bassel <larry.bassel@linaro.org> Reviewed-by: NKevin Hilman <khilman@linaro.org> Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
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由 Mark Brown 提交于
Add support for parsing the explicit topology bindings to discover the topology of the system. Since it is not currently clear how to map multi-level clusters for the scheduler all leaf clusters are presented to the scheduler at the same level. This should be enough to provide good support for current systems. Signed-off-by: NMark Brown <broonie@linaro.org> Reviewed-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com> Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
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由 Mark Brown 提交于
As a legacy of the way 32 bit ARM did things the topology code uses a null topology map by default and then overwrites it by mapping cores with no information to a cluster by themselves later. In order to make it simpler to reset things as part of recovering from parse failures in firmware information directly set this configuration on init. A core will always be its own sibling so there should be no risk of confusion with firmware provided information. Signed-off-by: NMark Brown <broonie@linaro.org> Reviewed-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com> Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
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由 Zi Shen Lim 提交于
Remove unused and deprecated mc_capable() and smt_capable(). Both were added recently by f6e763b9 ("arm64: topology: Implement basic CPU topology support"). Uses of both were removed by 8e7fbcbc ("sched: Remove stale power aware scheduling remnants and dysfunctional knobs"). Signed-off-by: NZi Shen Lim <zlim@broadcom.com> Signed-off-by: NMark Brown <broonie@linaro.org> Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
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- 16 5月, 2014 2 次提交
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由 Catalin Marinas 提交于
This reverts commit bc07c2c6. While the aim is increased security for --x memory maps, it does not protect against kernel level reads. Until SECCOMP is implemented for arm64, revert this patch to avoid giving a false idea of execute-only mappings. Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
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git://git.linaro.org/people/ard.biesheuvel/linux-arm由 Catalin Marinas 提交于
FPSIMD register bank context switching and crypto algorithms optimisations for arm64 from Ard Biesheuvel. * tag 'for-3.16' of git://git.linaro.org/people/ard.biesheuvel/linux-arm: arm64/crypto: AES-ECB/CBC/CTR/XTS using ARMv8 NEON and Crypto Extensions arm64: pull in <asm/simd.h> from asm-generic arm64/crypto: AES in CCM mode using ARMv8 Crypto Extensions arm64/crypto: AES using ARMv8 Crypto Extensions arm64/crypto: GHASH secure hash using ARMv8 Crypto Extensions arm64/crypto: SHA-224/SHA-256 using ARMv8 Crypto Extensions arm64/crypto: SHA-1 using ARMv8 Crypto Extensions arm64: add support for kernel mode NEON in interrupt context arm64: defer reloading a task's FPSIMD state to userland resume arm64: add abstractions for FPSIMD state manipulation asm-generic: allow generic unaligned access if the arch supports it Conflicts: arch/arm64/include/asm/thread_info.h
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- 15 5月, 2014 7 次提交
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由 Ard Biesheuvel 提交于
This adds ARMv8 implementations of AES in ECB, CBC, CTR and XTS modes, both for ARMv8 with Crypto Extensions and for plain ARMv8 NEON. The Crypto Extensions version can only run on ARMv8 implementations that have support for these optional extensions. The plain NEON version is a table based yet time invariant implementation. All S-box substitutions are performed in parallel, leveraging the wide range of ARMv8's tbl/tbx instructions, and the huge NEON register file, which can comfortably hold the entire S-box and still have room to spare for doing the actual computations. The key expansion routines were borrowed from aes_generic. Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: NHerbert Xu <herbert@gondor.apana.org.au>
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由 Ard Biesheuvel 提交于
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
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由 Ard Biesheuvel 提交于
This patch adds support for the AES-CCM encryption algorithm for CPUs that have support for the AES part of the ARM v8 Crypto Extensions. Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: NHerbert Xu <herbert@gondor.apana.org.au>
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由 Ard Biesheuvel 提交于
This patch adds support for the AES symmetric encryption algorithm for CPUs that have support for the AES part of the ARM v8 Crypto Extensions. Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: NHerbert Xu <herbert@gondor.apana.org.au>
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由 Ard Biesheuvel 提交于
This is a port to ARMv8 (Crypto Extensions) of the Intel implementation of the GHASH Secure Hash (used in the Galois/Counter chaining mode). It relies on the optional PMULL/PMULL2 instruction (polynomial multiply long, what Intel call carry-less multiply). Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: NHerbert Xu <herbert@gondor.apana.org.au>
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由 Ard Biesheuvel 提交于
This patch adds support for the SHA-224 and SHA-256 Secure Hash Algorithms for CPUs that have support for the SHA-2 part of the ARM v8 Crypto Extensions. Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: NHerbert Xu <herbert@gondor.apana.org.au>
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由 Ard Biesheuvel 提交于
This patch adds support for the SHA-1 Secure Hash Algorithm for CPUs that have support for the SHA-1 part of the ARM v8 Crypto Extensions. Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: NHerbert Xu <herbert@gondor.apana.org.au>
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- 12 5月, 2014 5 次提交
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由 AKASHI Takahiro 提交于
Some kernel files may include both linux/compat.h and asm/compat.h directly or indirectly. Since both header files contain is_compat_task() under !CONFIG_COMPAT, compiling them with !CONFIG_COMPAT will eventually fail. Such files include kernel/auditsc.c, kernel/seccomp.c and init/do_mountfs.c (do_mountfs.c may read asm/compat.h via asm/ftrace.h once ftrace is implemented). So this patch proactively 1) removes is_compat_task() under !CONFIG_COMPAT from asm/compat.h 2) replaces asm/compat.h to linux/compat.h in kernel/*.c, but asm/compat.h is still necessary in ptrace.c and process.c because they use is_compat_thread(). Acked-by: NWill Deacon <will.deacon@arm.com> Signed-off-by: NAKASHI Takahiro <takahiro.akashi@linaro.org> Signed-off-by: NWill Deacon <will.deacon@arm.com> Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
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由 AKASHI Takahiro 提交于
This macro, regs_return_value, is used mainly for audit to record system call's results, but may also be used in test_kprobes.c. Acked-by: NWill Deacon <will.deacon@arm.com> Acked-by: NRichard Guy Briggs <rgb@redhat.com> Signed-off-by: NAKASHI Takahiro <takahiro.akashi@linaro.org> Signed-off-by: NWill Deacon <will.deacon@arm.com> Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
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由 AKASHI Takahiro 提交于
As done in arm, this change makes it easy to confirm we invoke syscall related hooks, including syscall tracepoint, audit and seccomp which would be implemented later, in correct order. That is, undoing operations in the opposite order on exit that they were done on entry. Acked-by: NWill Deacon <will.deacon@arm.com> Signed-off-by: NAKASHI Takahiro <takahiro.akashi@linaro.org> Signed-off-by: NWill Deacon <will.deacon@arm.com> Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
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由 AKASHI Takahiro 提交于
Currently syscall_trace() is called only for ptrace. With additional TIF_xx flags defined, it is now called in all the cases of audit, ftrace and seccomp in addition to ptrace. Acked-by: NRichard Guy Briggs <rgb@redhat.com> Acked-by: NWill Deacon <will.deacon@arm.com> Signed-off-by: NAKASHI Takahiro <takahiro.akashi@linaro.org> Signed-off-by: NWill Deacon <will.deacon@arm.com> Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
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由 Will Deacon 提交于
Since mdscr_el1 is part of the debug register group, it is highly likely to be trapped by a hypervisor to prevent virtual machines from debugging (buggering?) each other. Unfortunately, this absolutely destroys our performance, since we access the register on many of our low-level fault handling paths to keep track of the various debug state machines. This patch removes our dependency on mdscr_el1 in the case that debugging is not being used. More specifically we: - Use TIF_SINGLESTEP to indicate that a task is stepping at EL0 and avoid disabling step in the MDSCR when we don't need to. MDSCR_EL1.SS handling is moved to kernel_entry, when trapping from userspace. - Ensure debug exceptions are re-enabled on *all* exception entry paths, even the debug exception handling path (where we re-enable exceptions after invoking the handler). Since we can now rely on MDSCR_EL1.SS being cleared by the entry code, exception handlers can usually enable debug immediately before enabling interrupts. - Remove all debug exception unmasking from ret_to_user and el1_preempt, since we will never get here with debug exceptions masked. This results in a slight change to kernel debug behaviour, where we now step into interrupt handlers and data aborts from EL1 when debugging the kernel, which is actually a useful thing to do. A side-effect of this is that it *does* potentially prevent stepping off {break,watch}points when there is a high-frequency interrupt source (e.g. a timer), so a debugger would need to use either breakpoints or manually disable interrupts to get around this issue. With this patch applied, guest performance is restored under KVM when debug register accesses are trapped (and we get a measurable performance increase on the host on Cortex-A57 too). Cc: Ian Campbell <ian.campbell@citrix.com> Tested-by: NMarc Zyngier <marc.zyngier@arm.com> Signed-off-by: NWill Deacon <will.deacon@arm.com> Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
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- 10 5月, 2014 8 次提交
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由 Will Deacon 提交于
In order to ensure ordering and completion of inner-shareable maintenance instructions (cache and TLB) on AArch64, we can use the -ish suffix to the dmb and dsb instructions respectively. This patch updates our low-level cache and tlb maintenance routines to use the inner-shareable barrier variants where appropriate. Acked-by: NCatalin Marinas <catalin.marinas@arm.com> Signed-off-by: NWill Deacon <will.deacon@arm.com> Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
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由 Will Deacon 提交于
In order to ensure completion of inner-shareable maintenance instructions (cache and TLB) on AArch64, we can use the -ish suffix to the dsb instruction. This patch relaxes our dsb sy instructions to dsb ish where possible. Acked-by: NCatalin Marinas <catalin.marinas@arm.com> Acked-by: NMarc Zyngier <marc.zyngier@arm.com> Signed-off-by: NWill Deacon <will.deacon@arm.com> Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
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由 Will Deacon 提交于
set_cpu_boot_mode_flag is used to identify which exception levels are encountered across the system by CPUs trying to enter the kernel. The basic algorithm is: if a CPU is booting at EL2, it will set a flag at an offset of #4 from __boot_cpu_mode, a cacheline-aligned variable. Otherwise, a flag is set at an offset of zero into the same cacheline. This enables us to check that all CPUs booted at the same exception level. This cacheline is written with the stage-1 MMU off (that is, via a strongly-ordered mapping) and will bypass any clean lines in the cache, leading to potential coherence problems when the variable is later checked via the normal, cacheable mapping of the kernel image. This patch reworks the broken flushing code so that we: (1) Use a DMB to order the strongly-ordered write of the cacheline against the subsequent cache-maintenance operation (by-VA operations only hazard against normal, cacheable accesses). (2) Use a single dc ivac instruction to invalidate any clean lines containing a stale copy of the line after it has been updated. Acked-by: NCatalin Marinas <catalin.marinas@arm.com> Signed-off-by: NWill Deacon <will.deacon@arm.com> Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
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由 Will Deacon 提交于
The recently introduced acquire/release accessors refer to smp_mb() in the !CONFIG_SMP case. This is confusing when reading the code, so use barrier() directly when we know we're UP. Acked-by: NCatalin Marinas <catalin.marinas@arm.com> Signed-off-by: NWill Deacon <will.deacon@arm.com> Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
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由 Will Deacon 提交于
Now that all callers of the barrier macros are updated to pass the mandatory options, update the macros so the option is actually used. Acked-by: NCatalin Marinas <catalin.marinas@arm.com> Signed-off-by: NWill Deacon <will.deacon@arm.com> Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
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由 Will Deacon 提交于
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: NCatalin Marinas <catalin.marinas@arm.com> Signed-off-by: NWill Deacon <will.deacon@arm.com> Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
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由 Steve Capper 提交于
The tlb maintainence functions: __cpu_flush_user_tlb_range and __cpu_flush_kern_tlb_range do not take into consideration the page granule when looping through the address range, and repeatedly flush tlb entries for the same page when operating with 64K pages. This patch re-works the logic s.t. we instead advance the loop by 1 << (PAGE_SHIFT - 12), so avoid repeating ourselves. Also the routines have been converted from assembler to static inline functions to aid with legibility and potential compiler optimisations. The isb() has been removed from flush_tlb_kernel_range(.) as it is only needed when changing the execute permission of a mapping. If one needs to set an area of the kernel as execute/non-execute an isb() must be inserted after the call to flush_tlb_kernel_range. Cc: Laura Abbott <lauraa@codeaurora.org> Signed-off-by: NSteve Capper <steve.capper@linaro.org> Acked-by: NWill Deacon <will.deacon@arm.com> Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
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由 Will Deacon 提交于
Some users of xchg() don't bother using the return value, which results in a compiler warning like the following (from kgdb): In file included from linux/arch/arm64/include/asm/atomic.h:27:0, from include/linux/atomic.h:4, from include/linux/spinlock.h:402, from include/linux/seqlock.h:35, from include/linux/time.h:5, from include/uapi/linux/timex.h:56, from include/linux/timex.h:56, from include/linux/sched.h:19, from include/linux/pid_namespace.h:4, from kernel/debug/debug_core.c:30: kernel/debug/debug_core.c: In function ‘kgdb_cpu_enter’: linux/arch/arm64/include/asm/cmpxchg.h:75:3: warning: value computed is not used [-Wunused-value] ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr)))) ^ linux/arch/arm64/include/asm/atomic.h:132:30: note: in expansion of macro ‘xchg’ #define atomic_xchg(v, new) (xchg(&((v)->counter), new)) kernel/debug/debug_core.c:504:4: note: in expansion of macro ‘atomic_xchg’ atomic_xchg(&kgdb_active, cpu); ^ This patch makes use of the same trick as we do for cmpxchg, by assigning the return value to a dummy variable in the xchg() macro itself. Signed-off-by: NWill Deacon <will.deacon@arm.com> Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
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- 09 5月, 2014 9 次提交
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由 Steve Capper 提交于
We have the capability to map 1GB level 1 blocks when using a 4K granule. This patch adjusts the create_mapping logic s.t. when mapping physical memory on boot, we attempt to use a 1GB block if both the VA and PA start and end are 1GB aligned. This both reduces the levels of lookup required to resolve a kernel logical address, as well as reduces TLB pressure on cores that support 1GB TLB entries. Signed-off-by: NSteve Capper <steve.capper@linaro.org> Tested-by: NJungseok Lee <jays.lee@samsung.com> [catalin.marinas@arm.com: s/prot_sect_kernel/PROT_SECT_NORMAL_EXEC/] Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
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由 Bjorn Helgaas 提交于
arm64 sets CONFIG_64BIT=y and hence uses the "long counter" atomic64_t definition from include/linux/types.h. Make atomic64_read() return "long", not "long long". Signed-off-by: NBjorn Helgaas <bhelgaas@google.com> Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
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由 Catalin Marinas 提交于
The primary aim of this patchset is to remove the pgprot_default and prot_sect_default global variables and rely strictly on predefined values. The original goal was to be able to run SMP kernels on UP hardware by not setting the Shareability bit. However, it is unlikely to see UP ARMv8 hardware and even if we do, the Shareability bit is no longer assumed to disable cacheable accesses. A side effect is that the device mappings now have the Shareability attribute set. The hardware, however, should ignore it since Device accesses are always Outer Shareable. Following the removal of the two global variables, there is some PROT_* macro reshuffling and cleanup, including the __PAGE_* macros (replaced by PAGE_*). Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com> Acked-by: NWill Deacon <will.deacon@arm.com>
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由 Catalin Marinas 提交于
The ARMv8 architecture allows execute-only user permissions by clearing the PTE_UXN and PTE_USER bits. The kernel, however, can still access such page, so execute-only page permission does not protect against read(2)/write(2) etc. accesses. Systems requiring such protection must implement/enable features like SECCOMP. This patch changes the arm64 __P100 and __S100 protection_map[] macros to the new __PAGE_EXECONLY attributes. A side effect is that pte_valid_user() no longer triggers for __PAGE_EXECONLY since PTE_USER isn't set. To work around this, the check is done on the PTE_NG bit via the pte_valid_ng() macro. VM_READ is also checked now for page faults. Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
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由 Catalin Marinas 提交于
This information is useful for instruction emulators to detect read/write and access size without having to decode the faulting instruction. The current patch exports it via sigcontext (struct esr_context) and is only valid for SIGSEGV and SIGBUS. Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
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由 Catalin Marinas 提交于
This patch removes the aux_context structure (and the containing file) to allow the placement of the _aarch64_ctx end magic based on the context stored on the signal stack. Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
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由 Catalin Marinas 提交于
For AArch32, bit 11 (WnR) of the FSR/ESR register is set when the fault was caused by a write access and applications like Qemu rely on such information being provided in sigcontext. This patch introduces the ESR_EL1 tracking for the arm64 kernel faults and sets bit 11 accordingly in compat sigcontext. Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
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由 Catalin Marinas 提交于
The synchronisation with the boot thread already happens in __cpu_up() via wait_for_completion_timeout(). In addition, __cpu_up() calls are protected by the cpu_add_remove_lock mutex and already serialised. Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
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由 Catalin Marinas 提交于
The hardware provides the maximum cache line size in the system via the CTR_EL0.CWG bits. This patch implements the cache_line_size() function to read such information, together with a sanity check if the statically defined L1_CACHE_BYTES is smaller than the hardware value. Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com> Acked-by: NWill Deacon <will.deacon@arm.com>
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- 08 5月, 2014 3 次提交
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由 Ard Biesheuvel 提交于
This patch modifies kernel_neon_begin() and kernel_neon_end(), so they may be called from any context. To address the case where only a couple of registers are needed, kernel_neon_begin_partial(u32) is introduced which takes as a parameter the number of bottom 'n' NEON q-registers required. To mark the end of such a partial section, the regular kernel_neon_end() should be used. Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
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由 Ard Biesheuvel 提交于
If a task gets scheduled out and back in again and nothing has touched its FPSIMD state in the mean time, there is really no reason to reload it from memory. Similarly, repeated calls to kernel_neon_begin() and kernel_neon_end() will preserve and restore the FPSIMD state every time. This patch defers the FPSIMD state restore to the last possible moment, i.e., right before the task returns to userland. If a task does not return to userland at all (for any reason), the existing FPSIMD state is preserved and may be reused by the owning task if it gets scheduled in again on the same CPU. This patch adds two more functions to abstract away from straight FPSIMD register file saves and restores: - fpsimd_restore_current_state -> ensure current's FPSIMD state is loaded - fpsimd_flush_task_state -> invalidate live copies of a task's FPSIMD state Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
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由 Ard Biesheuvel 提交于
There are two tacit assumptions in the FPSIMD handling code that will no longer hold after the next patch that optimizes away some FPSIMD state restores: . the FPSIMD registers of this CPU contain the userland FPSIMD state of task 'current'; . when switching to a task, its FPSIMD state will always be restored from memory. This patch adds the following functions to abstract away from straight FPSIMD register file saves and restores: - fpsimd_preserve_current_state -> ensure current's FPSIMD state is saved - fpsimd_update_current_state -> replace current's FPSIMD state Where necessary, the signal handling and fork code are updated to use the above wrappers instead of poking into the FPSIMD registers directly. Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
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