Commit d5a32b60 authored by Jing Zhang's avatar Jing Zhang Committed by Oliver Upton
Browse files

KVM: arm64: Allow userspace to change ID_AA64MMFR{0-2}_EL1 



Allow userspace to modify the guest-visible values of these ID
registers. Prevent changes to any of the virtualization features until
KVM picks up support for nested and we have a handle on managing NV
features.

Signed-off-by: default avatarJing Zhang <jingzhangos@google.com>
[oliver: prevent changes to EL2 features for now]
Reviewed-by: default avatarMarc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20231003230408.3405722-8-oliver.upton@linux.dev


Signed-off-by: default avatarOliver Upton <oliver.upton@linux.dev>
parent 56d77aa8

arch/arm64/kvm/sys_regs.c

+17 −3
Original line number Diff line number Diff line
@@ -2099,9 +2099,23 @@ static const struct sys_reg_desc sys_reg_descs[] = { 
	ID_UNALLOCATED(6,7),



	/* CRm=7 */

	ID_SANITISED(ID_AA64MMFR0_EL1),

	ID_SANITISED(ID_AA64MMFR1_EL1),

	ID_SANITISED(ID_AA64MMFR2_EL1),

	ID_WRITABLE(ID_AA64MMFR0_EL1, ~(ID_AA64MMFR0_EL1_RES0 |

					ID_AA64MMFR0_EL1_TGRAN4_2 |

					ID_AA64MMFR0_EL1_TGRAN64_2 |

					ID_AA64MMFR0_EL1_TGRAN16_2)),

	ID_WRITABLE(ID_AA64MMFR1_EL1, ~(ID_AA64MMFR1_EL1_RES0 |

					ID_AA64MMFR1_EL1_HCX |

					ID_AA64MMFR1_EL1_XNX |

					ID_AA64MMFR1_EL1_TWED |

					ID_AA64MMFR1_EL1_XNX |

					ID_AA64MMFR1_EL1_VH |

					ID_AA64MMFR1_EL1_VMIDBits)),

	ID_WRITABLE(ID_AA64MMFR2_EL1, ~(ID_AA64MMFR2_EL1_RES0 |

					ID_AA64MMFR2_EL1_EVT |

					ID_AA64MMFR2_EL1_FWB |

					ID_AA64MMFR2_EL1_IDS |

					ID_AA64MMFR2_EL1_NV |

					ID_AA64MMFR2_EL1_CCIDX)),

	ID_SANITISED(ID_AA64MMFR3_EL1),

	ID_UNALLOCATED(7,4),

	ID_UNALLOCATED(7,5),