This is a backport to v4.14 of the arm64 patches that exist in mainline and v4.19-stable to support CPUs that implement the SSBS capability, which gives the OS and user space control over whether Speculative Store Bypass is permitted in certain contexts. This gives a substantial performance boost on hardware that implements it.
At the same time, this series backports arm64 support for reporting of vulnerabilities via syfs. This is covered by the same series since it produces a much cleaner backport, where none of the 16 original patches required any changes beyond some manual mangling of the context to make them apply.
NOTE: in addition to the 16 patches that were also backported to v4.19 earlier, this series contains an additional 32 (!) patches that were included as prerequisites, even though by themselves they wouldn't qualify as stable backports. This was a conscious decision, and made the backport considerably cleaner, and should also make future backports of arm64 specific fixes less painful.
Build tested using a fair number of randconfig builds. Boot tested under KVM and on ThunderX2. Many thanks to Suzuki and Alexandru for the internal review and testing.
Cc: Will Deacon will@kernel.org Cc: Catalin Marinas catalin.marinas@arm.com Cc: Marc Zyngier maz@kernel.org Cc: Mark Rutland mark.rutland@arm.com Cc: Suzuki K Poulose suzuki.poulose@arm.com Cc: Jeremy Linton jeremy.linton@arm.com Cc: Andre Przywara andre.przywara@arm.com Cc: Alexandru Elisei alexandru.elisei@arm.com
Dave Martin (1): arm64: capabilities: Update prototype for enable call back
Dongjiu Geng (1): arm64: v8.4: Support for new floating point multiplication instructions
James Morse (1): arm64: sysreg: Move to use definitions for all the SCTLR bits
Jeremy Linton (6): arm64: add sysfs vulnerability show for meltdown arm64: Always enable ssb vulnerability detection arm64: Provide a command line to disable spectre_v2 mitigation arm64: Always enable spectre-v2 vulnerability detection arm64: add sysfs vulnerability show for spectre-v2 arm64: add sysfs vulnerability show for speculative store bypass
Josh Poimboeuf (1): arm64/speculation: Support 'mitigations=' cmdline option
Marc Zyngier (4): arm64: Get rid of __smccc_workaround_1_hvc_* arm64: Advertise mitigation of Spectre-v2, or lack thereof arm64: Force SSBS on context switch arm64: Use firmware to detect CPUs that are not affected by Spectre-v2
Mark Rutland (5): arm64: move SCTLR_EL{1,2} assertions to <asm/sysreg.h> arm64: add PSR_AA32_* definitions arm64: Introduce sysreg_clear_set() arm64: don't zero DIT on signal return arm64: fix SSBS sanitization
Mian Yousaf Kaukab (2): arm64: Add sysfs vulnerability show for spectre-v1 arm64: enable generic CPU vulnerabilites support
Shanker Donthineni (1): arm64: KVM: Use SMCCC_ARCH_WORKAROUND_1 for Falkor BP hardening
Suzuki K Poulose (22): arm64: Expose support for optional ARMv8-A features arm64: Fix the feature type for ID register fields arm64: Documentation: cpu-feature-registers: Remove RES0 fields arm64: Expose Arm v8.4 features arm64: capabilities: Move errata work around check on boot CPU arm64: capabilities: Move errata processing code arm64: capabilities: Prepare for fine grained capabilities arm64: capabilities: Add flags to handle the conflicts on late CPU arm64: capabilities: Unify the verification arm64: capabilities: Filter the entries based on a given mask arm64: capabilities: Prepare for grouping features and errata work arounds arm64: capabilities: Split the processing of errata work arounds arm64: capabilities: Allow features based on local CPU scope arm64: capabilities: Group handling of features and errata workarounds arm64: capabilities: Introduce weak features based on local CPU arm64: capabilities: Restrict KPTI detection to boot-time CPUs arm64: capabilities: Add support for features enabled early arm64: capabilities: Change scope of VHE to Boot CPU feature arm64: capabilities: Clean up midr range helpers arm64: Add helpers for checking CPU MIDR against a range arm64: Add MIDR encoding for Arm Cortex-A55 and Cortex-A35 arm64: capabilities: Add support for checks based on a list of MIDRs
Will Deacon (4): arm64: cpufeature: Detect SSBS and advertise to userspace arm64: ssbd: Add support for PSTATE.SSBS rather than trapping to EL3 KVM: arm64: Set SCTLR_EL2.DSSBS if SSBD is forcefully disabled and !vhe arm64: ssbs: Don't treat CPUs with SSBS as unaffected by SSB
Documentation/admin-guide/kernel-parameters.txt | 16 +- Documentation/arm64/cpu-feature-registers.txt | 26 +- arch/arm64/Kconfig | 1 + arch/arm64/include/asm/cpucaps.h | 6 +- arch/arm64/include/asm/cpufeature.h | 250 +++++++++- arch/arm64/include/asm/cputype.h | 43 ++ arch/arm64/include/asm/kvm_asm.h | 2 - arch/arm64/include/asm/kvm_host.h | 11 + arch/arm64/include/asm/processor.h | 22 +- arch/arm64/include/asm/ptrace.h | 58 ++- arch/arm64/include/asm/sysreg.h | 95 +++- arch/arm64/include/asm/virt.h | 6 - arch/arm64/include/uapi/asm/hwcap.h | 12 + arch/arm64/include/uapi/asm/ptrace.h | 1 + arch/arm64/kernel/bpi.S | 19 +- arch/arm64/kernel/cpu_errata.c | 495 +++++++++++-------- arch/arm64/kernel/cpufeature.c | 517 ++++++++++++++------ arch/arm64/kernel/cpuinfo.c | 12 + arch/arm64/kernel/fpsimd.c | 1 + arch/arm64/kernel/head.S | 13 +- arch/arm64/kernel/process.c | 31 ++ arch/arm64/kernel/ptrace.c | 13 +- arch/arm64/kernel/smp.c | 44 -- arch/arm64/kernel/ssbd.c | 22 + arch/arm64/kernel/traps.c | 4 +- arch/arm64/kvm/hyp/entry.S | 12 - arch/arm64/kvm/hyp/switch.c | 10 - arch/arm64/kvm/hyp/sysreg-sr.c | 11 + arch/arm64/mm/fault.c | 3 +- arch/arm64/mm/proc.S | 24 +- 30 files changed, 1268 insertions(+), 512 deletions(-)