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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /arch/arm64/kvm/debug.c
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Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
Diffstat (limited to 'arch/arm64/kvm/debug.c')
-rw-r--r--arch/arm64/kvm/debug.c344
1 files changed, 344 insertions, 0 deletions
diff --git a/arch/arm64/kvm/debug.c b/arch/arm64/kvm/debug.c
new file mode 100644
index 000000000..55f80fb93
--- /dev/null
+++ b/arch/arm64/kvm/debug.c
@@ -0,0 +1,344 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Debug and Guest Debug support
+ *
+ * Copyright (C) 2015 - Linaro Ltd
+ * Author: Alex Bennée <alex.bennee@linaro.org>
+ */
+
+#include <linux/kvm_host.h>
+#include <linux/hw_breakpoint.h>
+
+#include <asm/debug-monitors.h>
+#include <asm/kvm_asm.h>
+#include <asm/kvm_arm.h>
+#include <asm/kvm_emulate.h>
+
+#include "trace.h"
+
+/* These are the bits of MDSCR_EL1 we may manipulate */
+#define MDSCR_EL1_DEBUG_MASK (DBG_MDSCR_SS | \
+ DBG_MDSCR_KDE | \
+ DBG_MDSCR_MDE)
+
+static DEFINE_PER_CPU(u64, mdcr_el2);
+
+/**
+ * save/restore_guest_debug_regs
+ *
+ * For some debug operations we need to tweak some guest registers. As
+ * a result we need to save the state of those registers before we
+ * make those modifications.
+ *
+ * Guest access to MDSCR_EL1 is trapped by the hypervisor and handled
+ * after we have restored the preserved value to the main context.
+ *
+ * When single-step is enabled by userspace, we tweak PSTATE.SS on every
+ * guest entry. Preserve PSTATE.SS so we can restore the original value
+ * for the vcpu after the single-step is disabled.
+ */
+static void save_guest_debug_regs(struct kvm_vcpu *vcpu)
+{
+ u64 val = vcpu_read_sys_reg(vcpu, MDSCR_EL1);
+
+ vcpu->arch.guest_debug_preserved.mdscr_el1 = val;
+
+ trace_kvm_arm_set_dreg32("Saved MDSCR_EL1",
+ vcpu->arch.guest_debug_preserved.mdscr_el1);
+
+ vcpu->arch.guest_debug_preserved.pstate_ss =
+ (*vcpu_cpsr(vcpu) & DBG_SPSR_SS);
+}
+
+static void restore_guest_debug_regs(struct kvm_vcpu *vcpu)
+{
+ u64 val = vcpu->arch.guest_debug_preserved.mdscr_el1;
+
+ vcpu_write_sys_reg(vcpu, val, MDSCR_EL1);
+
+ trace_kvm_arm_set_dreg32("Restored MDSCR_EL1",
+ vcpu_read_sys_reg(vcpu, MDSCR_EL1));
+
+ if (vcpu->arch.guest_debug_preserved.pstate_ss)
+ *vcpu_cpsr(vcpu) |= DBG_SPSR_SS;
+ else
+ *vcpu_cpsr(vcpu) &= ~DBG_SPSR_SS;
+}
+
+/**
+ * kvm_arm_init_debug - grab what we need for debug
+ *
+ * Currently the sole task of this function is to retrieve the initial
+ * value of mdcr_el2 so we can preserve MDCR_EL2.HPMN which has
+ * presumably been set-up by some knowledgeable bootcode.
+ *
+ * It is called once per-cpu during CPU hyp initialisation.
+ */
+
+void kvm_arm_init_debug(void)
+{
+ __this_cpu_write(mdcr_el2, kvm_call_hyp_ret(__kvm_get_mdcr_el2));
+}
+
+/**
+ * kvm_arm_setup_mdcr_el2 - configure vcpu mdcr_el2 value
+ *
+ * @vcpu: the vcpu pointer
+ *
+ * This ensures we will trap access to:
+ * - Performance monitors (MDCR_EL2_TPM/MDCR_EL2_TPMCR)
+ * - Debug ROM Address (MDCR_EL2_TDRA)
+ * - OS related registers (MDCR_EL2_TDOSA)
+ * - Statistical profiler (MDCR_EL2_TPMS/MDCR_EL2_E2PB)
+ * - Self-hosted Trace Filter controls (MDCR_EL2_TTRF)
+ * - Self-hosted Trace (MDCR_EL2_TTRF/MDCR_EL2_E2TB)
+ */
+static void kvm_arm_setup_mdcr_el2(struct kvm_vcpu *vcpu)
+{
+ /*
+ * This also clears MDCR_EL2_E2PB_MASK and MDCR_EL2_E2TB_MASK
+ * to disable guest access to the profiling and trace buffers
+ */
+ vcpu->arch.mdcr_el2 = __this_cpu_read(mdcr_el2) & MDCR_EL2_HPMN_MASK;
+ vcpu->arch.mdcr_el2 |= (MDCR_EL2_TPM |
+ MDCR_EL2_TPMS |
+ MDCR_EL2_TTRF |
+ MDCR_EL2_TPMCR |
+ MDCR_EL2_TDRA |
+ MDCR_EL2_TDOSA);
+
+ /* Is the VM being debugged by userspace? */
+ if (vcpu->guest_debug)
+ /* Route all software debug exceptions to EL2 */
+ vcpu->arch.mdcr_el2 |= MDCR_EL2_TDE;
+
+ /*
+ * Trap debug register access when one of the following is true:
+ * - Userspace is using the hardware to debug the guest
+ * (KVM_GUESTDBG_USE_HW is set).
+ * - The guest is not using debug (DEBUG_DIRTY clear).
+ * - The guest has enabled the OS Lock (debug exceptions are blocked).
+ */
+ if ((vcpu->guest_debug & KVM_GUESTDBG_USE_HW) ||
+ !vcpu_get_flag(vcpu, DEBUG_DIRTY) ||
+ kvm_vcpu_os_lock_enabled(vcpu))
+ vcpu->arch.mdcr_el2 |= MDCR_EL2_TDA;
+
+ trace_kvm_arm_set_dreg32("MDCR_EL2", vcpu->arch.mdcr_el2);
+}
+
+/**
+ * kvm_arm_vcpu_init_debug - setup vcpu debug traps
+ *
+ * @vcpu: the vcpu pointer
+ *
+ * Set vcpu initial mdcr_el2 value.
+ */
+void kvm_arm_vcpu_init_debug(struct kvm_vcpu *vcpu)
+{
+ preempt_disable();
+ kvm_arm_setup_mdcr_el2(vcpu);
+ preempt_enable();
+}
+
+/**
+ * kvm_arm_reset_debug_ptr - reset the debug ptr to point to the vcpu state
+ */
+
+void kvm_arm_reset_debug_ptr(struct kvm_vcpu *vcpu)
+{
+ vcpu->arch.debug_ptr = &vcpu->arch.vcpu_debug_state;
+}
+
+/**
+ * kvm_arm_setup_debug - set up debug related stuff
+ *
+ * @vcpu: the vcpu pointer
+ *
+ * This is called before each entry into the hypervisor to setup any
+ * debug related registers.
+ *
+ * Additionally, KVM only traps guest accesses to the debug registers if
+ * the guest is not actively using them (see the DEBUG_DIRTY
+ * flag on vcpu->arch.iflags). Since the guest must not interfere
+ * with the hardware state when debugging the guest, we must ensure that
+ * trapping is enabled whenever we are debugging the guest using the
+ * debug registers.
+ */
+
+void kvm_arm_setup_debug(struct kvm_vcpu *vcpu)
+{
+ unsigned long mdscr, orig_mdcr_el2 = vcpu->arch.mdcr_el2;
+
+ trace_kvm_arm_setup_debug(vcpu, vcpu->guest_debug);
+
+ kvm_arm_setup_mdcr_el2(vcpu);
+
+ /* Check if we need to use the debug registers. */
+ if (vcpu->guest_debug || kvm_vcpu_os_lock_enabled(vcpu)) {
+ /* Save guest debug state */
+ save_guest_debug_regs(vcpu);
+
+ /*
+ * Single Step (ARM ARM D2.12.3 The software step state
+ * machine)
+ *
+ * If we are doing Single Step we need to manipulate
+ * the guest's MDSCR_EL1.SS and PSTATE.SS. Once the
+ * step has occurred the hypervisor will trap the
+ * debug exception and we return to userspace.
+ *
+ * If the guest attempts to single step its userspace
+ * we would have to deal with a trapped exception
+ * while in the guest kernel. Because this would be
+ * hard to unwind we suppress the guest's ability to
+ * do so by masking MDSCR_EL.SS.
+ *
+ * This confuses guest debuggers which use
+ * single-step behind the scenes but everything
+ * returns to normal once the host is no longer
+ * debugging the system.
+ */
+ if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP) {
+ /*
+ * If the software step state at the last guest exit
+ * was Active-pending, we don't set DBG_SPSR_SS so
+ * that the state is maintained (to not run another
+ * single-step until the pending Software Step
+ * exception is taken).
+ */
+ if (!vcpu_get_flag(vcpu, DBG_SS_ACTIVE_PENDING))
+ *vcpu_cpsr(vcpu) |= DBG_SPSR_SS;
+ else
+ *vcpu_cpsr(vcpu) &= ~DBG_SPSR_SS;
+
+ mdscr = vcpu_read_sys_reg(vcpu, MDSCR_EL1);
+ mdscr |= DBG_MDSCR_SS;
+ vcpu_write_sys_reg(vcpu, mdscr, MDSCR_EL1);
+ } else {
+ mdscr = vcpu_read_sys_reg(vcpu, MDSCR_EL1);
+ mdscr &= ~DBG_MDSCR_SS;
+ vcpu_write_sys_reg(vcpu, mdscr, MDSCR_EL1);
+ }
+
+ trace_kvm_arm_set_dreg32("SPSR_EL2", *vcpu_cpsr(vcpu));
+
+ /*
+ * HW Breakpoints and watchpoints
+ *
+ * We simply switch the debug_ptr to point to our new
+ * external_debug_state which has been populated by the
+ * debug ioctl. The existing DEBUG_DIRTY mechanism ensures
+ * the registers are updated on the world switch.
+ */
+ if (vcpu->guest_debug & KVM_GUESTDBG_USE_HW) {
+ /* Enable breakpoints/watchpoints */
+ mdscr = vcpu_read_sys_reg(vcpu, MDSCR_EL1);
+ mdscr |= DBG_MDSCR_MDE;
+ vcpu_write_sys_reg(vcpu, mdscr, MDSCR_EL1);
+
+ vcpu->arch.debug_ptr = &vcpu->arch.external_debug_state;
+ vcpu_set_flag(vcpu, DEBUG_DIRTY);
+
+ trace_kvm_arm_set_regset("BKPTS", get_num_brps(),
+ &vcpu->arch.debug_ptr->dbg_bcr[0],
+ &vcpu->arch.debug_ptr->dbg_bvr[0]);
+
+ trace_kvm_arm_set_regset("WAPTS", get_num_wrps(),
+ &vcpu->arch.debug_ptr->dbg_wcr[0],
+ &vcpu->arch.debug_ptr->dbg_wvr[0]);
+
+ /*
+ * The OS Lock blocks debug exceptions in all ELs when it is
+ * enabled. If the guest has enabled the OS Lock, constrain its
+ * effects to the guest. Emulate the behavior by clearing
+ * MDSCR_EL1.MDE. In so doing, we ensure that host debug
+ * exceptions are unaffected by guest configuration of the OS
+ * Lock.
+ */
+ } else if (kvm_vcpu_os_lock_enabled(vcpu)) {
+ mdscr = vcpu_read_sys_reg(vcpu, MDSCR_EL1);
+ mdscr &= ~DBG_MDSCR_MDE;
+ vcpu_write_sys_reg(vcpu, mdscr, MDSCR_EL1);
+ }
+ }
+
+ BUG_ON(!vcpu->guest_debug &&
+ vcpu->arch.debug_ptr != &vcpu->arch.vcpu_debug_state);
+
+ /* If KDE or MDE are set, perform a full save/restore cycle. */
+ if (vcpu_read_sys_reg(vcpu, MDSCR_EL1) & (DBG_MDSCR_KDE | DBG_MDSCR_MDE))
+ vcpu_set_flag(vcpu, DEBUG_DIRTY);
+
+ /* Write mdcr_el2 changes since vcpu_load on VHE systems */
+ if (has_vhe() && orig_mdcr_el2 != vcpu->arch.mdcr_el2)
+ write_sysreg(vcpu->arch.mdcr_el2, mdcr_el2);
+
+ trace_kvm_arm_set_dreg32("MDSCR_EL1", vcpu_read_sys_reg(vcpu, MDSCR_EL1));
+}
+
+void kvm_arm_clear_debug(struct kvm_vcpu *vcpu)
+{
+ trace_kvm_arm_clear_debug(vcpu->guest_debug);
+
+ /*
+ * Restore the guest's debug registers if we were using them.
+ */
+ if (vcpu->guest_debug || kvm_vcpu_os_lock_enabled(vcpu)) {
+ if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP) {
+ if (!(*vcpu_cpsr(vcpu) & DBG_SPSR_SS))
+ /*
+ * Mark the vcpu as ACTIVE_PENDING
+ * until Software Step exception is taken.
+ */
+ vcpu_set_flag(vcpu, DBG_SS_ACTIVE_PENDING);
+ }
+
+ restore_guest_debug_regs(vcpu);
+
+ /*
+ * If we were using HW debug we need to restore the
+ * debug_ptr to the guest debug state.
+ */
+ if (vcpu->guest_debug & KVM_GUESTDBG_USE_HW) {
+ kvm_arm_reset_debug_ptr(vcpu);
+
+ trace_kvm_arm_set_regset("BKPTS", get_num_brps(),
+ &vcpu->arch.debug_ptr->dbg_bcr[0],
+ &vcpu->arch.debug_ptr->dbg_bvr[0]);
+
+ trace_kvm_arm_set_regset("WAPTS", get_num_wrps(),
+ &vcpu->arch.debug_ptr->dbg_wcr[0],
+ &vcpu->arch.debug_ptr->dbg_wvr[0]);
+ }
+ }
+}
+
+void kvm_arch_vcpu_load_debug_state_flags(struct kvm_vcpu *vcpu)
+{
+ u64 dfr0;
+
+ /* For VHE, there is nothing to do */
+ if (has_vhe())
+ return;
+
+ dfr0 = read_sysreg(id_aa64dfr0_el1);
+ /*
+ * If SPE is present on this CPU and is available at current EL,
+ * we may need to check if the host state needs to be saved.
+ */
+ if (cpuid_feature_extract_unsigned_field(dfr0, ID_AA64DFR0_EL1_PMSVer_SHIFT) &&
+ !(read_sysreg_s(SYS_PMBIDR_EL1) & BIT(PMBIDR_EL1_P_SHIFT)))
+ vcpu_set_flag(vcpu, DEBUG_STATE_SAVE_SPE);
+
+ /* Check if we have TRBE implemented and available at the host */
+ if (cpuid_feature_extract_unsigned_field(dfr0, ID_AA64DFR0_EL1_TraceBuffer_SHIFT) &&
+ !(read_sysreg_s(SYS_TRBIDR_EL1) & TRBIDR_PROG))
+ vcpu_set_flag(vcpu, DEBUG_STATE_SAVE_TRBE);
+}
+
+void kvm_arch_vcpu_put_debug_state_flags(struct kvm_vcpu *vcpu)
+{
+ vcpu_clear_flag(vcpu, DEBUG_STATE_SAVE_SPE);
+ vcpu_clear_flag(vcpu, DEBUG_STATE_SAVE_TRBE);
+}