From: Fuad Tabba Date: Thu, 7 Aug 2025 12:01:31 +0000 (+0100) Subject: KVM: arm64: Handle AIDR_EL1 and REVIDR_EL1 in host for protected VMs X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=eaa43934b412f0381598e308b6a25d6c9a5dce2d;p=users%2Fjedix%2Flinux-maple.git KVM: arm64: Handle AIDR_EL1 and REVIDR_EL1 in host for protected VMs Since commit 17efc1acee62 ("arm64: Expose AIDR_EL1 via sysfs"), AIDR_EL1 is read early during boot. Therefore, a guest running as a protected VM will fail to boot because when it attempts to access AIDR_EL1, access to that register is restricted in pKVM for protected guests. Similar to how MIDR_EL1 is handled by the host for protected VMs, let the host handle accesses to AIDR_EL1 as well as REVIDR_EL1. However note that, unlike MIDR_EL1, AIDR_EL1 and REVIDR_EL1 are trapped by HCR_EL2.TID1. Therefore, explicitly mark them as handled by the host for protected VMs. TID1 is always set in pKVM, because it needs to restrict access to SMIDR_EL1, which is also trapped by that bit. Reported-by: Will Deacon Signed-off-by: Fuad Tabba Link: https://lore.kernel.org/r/20250807120133.871892-2-tabba@google.com Signed-off-by: Oliver Upton --- diff --git a/arch/arm64/kvm/hyp/nvhe/sys_regs.c b/arch/arm64/kvm/hyp/nvhe/sys_regs.c index 1ddd9ed3cbb3a..bbd60013cf9e9 100644 --- a/arch/arm64/kvm/hyp/nvhe/sys_regs.c +++ b/arch/arm64/kvm/hyp/nvhe/sys_regs.c @@ -372,6 +372,9 @@ static const struct sys_reg_desc pvm_sys_reg_descs[] = { /* Debug and Trace Registers are restricted. */ + /* Group 1 ID registers */ + HOST_HANDLED(SYS_REVIDR_EL1), + /* AArch64 mappings of the AArch32 ID registers */ /* CRm=1 */ AARCH32(SYS_ID_PFR0_EL1), @@ -460,6 +463,7 @@ static const struct sys_reg_desc pvm_sys_reg_descs[] = { HOST_HANDLED(SYS_CCSIDR_EL1), HOST_HANDLED(SYS_CLIDR_EL1), + HOST_HANDLED(SYS_AIDR_EL1), HOST_HANDLED(SYS_CSSELR_EL1), HOST_HANDLED(SYS_CTR_EL0),