linux/arch/arm64/include/asm/cpucaps.h
Rob Herring 96d389ca10 arm64: Add workaround for Arm Cortex-A77 erratum 1508412
On Cortex-A77 r0p0 and r1p0, a sequence of a non-cacheable or device load
and a store exclusive or PAR_EL1 read can cause a deadlock.

The workaround requires a DMB SY before and after a PAR_EL1 register
read. In addition, it's possible an interrupt (doing a device read) or
KVM guest exit could be taken between the DMB and PAR read, so we
also need a DMB before returning from interrupt and before returning to
a guest.

A deadlock is still possible with the workaround as KVM guests must also
have the workaround. IOW, a malicious guest can deadlock an affected
systems.

This workaround also depends on a firmware counterpart to enable the h/w
to insert DMB SY after load and store exclusive instructions. See the
errata document SDEN-1152370 v10 [1] for more information.

[1] https://static.docs.arm.com/101992/0010/Arm_Cortex_A77_MP074_Software_Developer_Errata_Notice_v10.pdf

Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Julien Thierry <julien.thierry.kdev@gmail.com>
Cc: kvmarm@lists.cs.columbia.edu
Link: https://lore.kernel.org/r/20201028182839.166037-2-robh@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2020-10-29 12:56:01 +00:00

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2.2 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* arch/arm64/include/asm/cpucaps.h
*
* Copyright (C) 2016 ARM Ltd.
*/
#ifndef __ASM_CPUCAPS_H
#define __ASM_CPUCAPS_H
#define ARM64_WORKAROUND_CLEAN_CACHE 0
#define ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE 1
#define ARM64_WORKAROUND_845719 2
#define ARM64_HAS_SYSREG_GIC_CPUIF 3
#define ARM64_HAS_PAN 4
#define ARM64_HAS_LSE_ATOMICS 5
#define ARM64_WORKAROUND_CAVIUM_23154 6
#define ARM64_WORKAROUND_834220 7
#define ARM64_HAS_NO_HW_PREFETCH 8
#define ARM64_HAS_UAO 9
#define ARM64_ALT_PAN_NOT_UAO 10
#define ARM64_HAS_VIRT_HOST_EXTN 11
#define ARM64_WORKAROUND_CAVIUM_27456 12
#define ARM64_HAS_32BIT_EL0 13
#define ARM64_HARDEN_EL2_VECTORS 14
#define ARM64_HAS_CNP 15
#define ARM64_HAS_NO_FPSIMD 16
#define ARM64_WORKAROUND_REPEAT_TLBI 17
#define ARM64_WORKAROUND_QCOM_FALKOR_E1003 18
#define ARM64_WORKAROUND_858921 19
#define ARM64_WORKAROUND_CAVIUM_30115 20
#define ARM64_HAS_DCPOP 21
#define ARM64_SVE 22
#define ARM64_UNMAP_KERNEL_AT_EL0 23
#define ARM64_SPECTRE_V2 24
#define ARM64_HAS_RAS_EXTN 25
#define ARM64_WORKAROUND_843419 26
#define ARM64_HAS_CACHE_IDC 27
#define ARM64_HAS_CACHE_DIC 28
#define ARM64_HW_DBM 29
#define ARM64_SPECTRE_V4 30
#define ARM64_MISMATCHED_CACHE_TYPE 31
#define ARM64_HAS_STAGE2_FWB 32
#define ARM64_HAS_CRC32 33
#define ARM64_SSBS 34
#define ARM64_WORKAROUND_1418040 35
#define ARM64_HAS_SB 36
#define ARM64_WORKAROUND_SPECULATIVE_AT 37
#define ARM64_HAS_ADDRESS_AUTH_ARCH 38
#define ARM64_HAS_ADDRESS_AUTH_IMP_DEF 39
#define ARM64_HAS_GENERIC_AUTH_ARCH 40
#define ARM64_HAS_GENERIC_AUTH_IMP_DEF 41
#define ARM64_HAS_IRQ_PRIO_MASKING 42
#define ARM64_HAS_DCPODP 43
#define ARM64_WORKAROUND_1463225 44
#define ARM64_WORKAROUND_CAVIUM_TX2_219_TVM 45
#define ARM64_WORKAROUND_CAVIUM_TX2_219_PRFM 46
#define ARM64_WORKAROUND_1542419 47
#define ARM64_HAS_E0PD 48
#define ARM64_HAS_RNG 49
#define ARM64_HAS_AMU_EXTN 50
#define ARM64_HAS_ADDRESS_AUTH 51
#define ARM64_HAS_GENERIC_AUTH 52
#define ARM64_HAS_32BIT_EL1 53
#define ARM64_BTI 54
#define ARM64_HAS_ARMv8_4_TTL 55
#define ARM64_HAS_TLB_RANGE 56
#define ARM64_MTE 57
#define ARM64_WORKAROUND_1508412 58
#define ARM64_NCAPS 59
#endif /* __ASM_CPUCAPS_H */