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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 /tools/testing/selftests/kvm/x86_64/nested_exceptions_test.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 'tools/testing/selftests/kvm/x86_64/nested_exceptions_test.c')
-rw-r--r--tools/testing/selftests/kvm/x86_64/nested_exceptions_test.c295
1 files changed, 295 insertions, 0 deletions
diff --git a/tools/testing/selftests/kvm/x86_64/nested_exceptions_test.c b/tools/testing/selftests/kvm/x86_64/nested_exceptions_test.c
new file mode 100644
index 000000000..ac33835f7
--- /dev/null
+++ b/tools/testing/selftests/kvm/x86_64/nested_exceptions_test.c
@@ -0,0 +1,295 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#define _GNU_SOURCE /* for program_invocation_short_name */
+
+#include "test_util.h"
+#include "kvm_util.h"
+#include "processor.h"
+#include "vmx.h"
+#include "svm_util.h"
+
+#define L2_GUEST_STACK_SIZE 256
+
+/*
+ * Arbitrary, never shoved into KVM/hardware, just need to avoid conflict with
+ * the "real" exceptions used, #SS/#GP/#DF (12/13/8).
+ */
+#define FAKE_TRIPLE_FAULT_VECTOR 0xaa
+
+/* Arbitrary 32-bit error code injected by this test. */
+#define SS_ERROR_CODE 0xdeadbeef
+
+/*
+ * Bit '0' is set on Intel if the exception occurs while delivering a previous
+ * event/exception. AMD's wording is ambiguous, but presumably the bit is set
+ * if the exception occurs while delivering an external event, e.g. NMI or INTR,
+ * but not for exceptions that occur when delivering other exceptions or
+ * software interrupts.
+ *
+ * Note, Intel's name for it, "External event", is misleading and much more
+ * aligned with AMD's behavior, but the SDM is quite clear on its behavior.
+ */
+#define ERROR_CODE_EXT_FLAG BIT(0)
+
+/*
+ * Bit '1' is set if the fault occurred when looking up a descriptor in the
+ * IDT, which is the case here as the IDT is empty/NULL.
+ */
+#define ERROR_CODE_IDT_FLAG BIT(1)
+
+/*
+ * The #GP that occurs when vectoring #SS should show the index into the IDT
+ * for #SS, plus have the "IDT flag" set.
+ */
+#define GP_ERROR_CODE_AMD ((SS_VECTOR * 8) | ERROR_CODE_IDT_FLAG)
+#define GP_ERROR_CODE_INTEL ((SS_VECTOR * 8) | ERROR_CODE_IDT_FLAG | ERROR_CODE_EXT_FLAG)
+
+/*
+ * Intel and AMD both shove '0' into the error code on #DF, regardless of what
+ * led to the double fault.
+ */
+#define DF_ERROR_CODE 0
+
+#define INTERCEPT_SS (BIT_ULL(SS_VECTOR))
+#define INTERCEPT_SS_DF (INTERCEPT_SS | BIT_ULL(DF_VECTOR))
+#define INTERCEPT_SS_GP_DF (INTERCEPT_SS_DF | BIT_ULL(GP_VECTOR))
+
+static void l2_ss_pending_test(void)
+{
+ GUEST_SYNC(SS_VECTOR);
+}
+
+static void l2_ss_injected_gp_test(void)
+{
+ GUEST_SYNC(GP_VECTOR);
+}
+
+static void l2_ss_injected_df_test(void)
+{
+ GUEST_SYNC(DF_VECTOR);
+}
+
+static void l2_ss_injected_tf_test(void)
+{
+ GUEST_SYNC(FAKE_TRIPLE_FAULT_VECTOR);
+}
+
+static void svm_run_l2(struct svm_test_data *svm, void *l2_code, int vector,
+ uint32_t error_code)
+{
+ struct vmcb *vmcb = svm->vmcb;
+ struct vmcb_control_area *ctrl = &vmcb->control;
+
+ vmcb->save.rip = (u64)l2_code;
+ run_guest(vmcb, svm->vmcb_gpa);
+
+ if (vector == FAKE_TRIPLE_FAULT_VECTOR)
+ return;
+
+ GUEST_ASSERT_EQ(ctrl->exit_code, (SVM_EXIT_EXCP_BASE + vector));
+ GUEST_ASSERT_EQ(ctrl->exit_info_1, error_code);
+}
+
+static void l1_svm_code(struct svm_test_data *svm)
+{
+ struct vmcb_control_area *ctrl = &svm->vmcb->control;
+ unsigned long l2_guest_stack[L2_GUEST_STACK_SIZE];
+
+ generic_svm_setup(svm, NULL, &l2_guest_stack[L2_GUEST_STACK_SIZE]);
+ svm->vmcb->save.idtr.limit = 0;
+ ctrl->intercept |= BIT_ULL(INTERCEPT_SHUTDOWN);
+
+ ctrl->intercept_exceptions = INTERCEPT_SS_GP_DF;
+ svm_run_l2(svm, l2_ss_pending_test, SS_VECTOR, SS_ERROR_CODE);
+ svm_run_l2(svm, l2_ss_injected_gp_test, GP_VECTOR, GP_ERROR_CODE_AMD);
+
+ ctrl->intercept_exceptions = INTERCEPT_SS_DF;
+ svm_run_l2(svm, l2_ss_injected_df_test, DF_VECTOR, DF_ERROR_CODE);
+
+ ctrl->intercept_exceptions = INTERCEPT_SS;
+ svm_run_l2(svm, l2_ss_injected_tf_test, FAKE_TRIPLE_FAULT_VECTOR, 0);
+ GUEST_ASSERT_EQ(ctrl->exit_code, SVM_EXIT_SHUTDOWN);
+
+ GUEST_DONE();
+}
+
+static void vmx_run_l2(void *l2_code, int vector, uint32_t error_code)
+{
+ GUEST_ASSERT(!vmwrite(GUEST_RIP, (u64)l2_code));
+
+ GUEST_ASSERT_EQ(vector == SS_VECTOR ? vmlaunch() : vmresume(), 0);
+
+ if (vector == FAKE_TRIPLE_FAULT_VECTOR)
+ return;
+
+ GUEST_ASSERT_EQ(vmreadz(VM_EXIT_REASON), EXIT_REASON_EXCEPTION_NMI);
+ GUEST_ASSERT_EQ((vmreadz(VM_EXIT_INTR_INFO) & 0xff), vector);
+ GUEST_ASSERT_EQ(vmreadz(VM_EXIT_INTR_ERROR_CODE), error_code);
+}
+
+static void l1_vmx_code(struct vmx_pages *vmx)
+{
+ unsigned long l2_guest_stack[L2_GUEST_STACK_SIZE];
+
+ GUEST_ASSERT_EQ(prepare_for_vmx_operation(vmx), true);
+
+ GUEST_ASSERT_EQ(load_vmcs(vmx), true);
+
+ prepare_vmcs(vmx, NULL, &l2_guest_stack[L2_GUEST_STACK_SIZE]);
+ GUEST_ASSERT_EQ(vmwrite(GUEST_IDTR_LIMIT, 0), 0);
+
+ /*
+ * VMX disallows injecting an exception with error_code[31:16] != 0,
+ * and hardware will never generate a VM-Exit with bits 31:16 set.
+ * KVM should likewise truncate the "bad" userspace value.
+ */
+ GUEST_ASSERT_EQ(vmwrite(EXCEPTION_BITMAP, INTERCEPT_SS_GP_DF), 0);
+ vmx_run_l2(l2_ss_pending_test, SS_VECTOR, (u16)SS_ERROR_CODE);
+ vmx_run_l2(l2_ss_injected_gp_test, GP_VECTOR, GP_ERROR_CODE_INTEL);
+
+ GUEST_ASSERT_EQ(vmwrite(EXCEPTION_BITMAP, INTERCEPT_SS_DF), 0);
+ vmx_run_l2(l2_ss_injected_df_test, DF_VECTOR, DF_ERROR_CODE);
+
+ GUEST_ASSERT_EQ(vmwrite(EXCEPTION_BITMAP, INTERCEPT_SS), 0);
+ vmx_run_l2(l2_ss_injected_tf_test, FAKE_TRIPLE_FAULT_VECTOR, 0);
+ GUEST_ASSERT_EQ(vmreadz(VM_EXIT_REASON), EXIT_REASON_TRIPLE_FAULT);
+
+ GUEST_DONE();
+}
+
+static void __attribute__((__flatten__)) l1_guest_code(void *test_data)
+{
+ if (this_cpu_has(X86_FEATURE_SVM))
+ l1_svm_code(test_data);
+ else
+ l1_vmx_code(test_data);
+}
+
+static void assert_ucall_vector(struct kvm_vcpu *vcpu, int vector)
+{
+ struct kvm_run *run = vcpu->run;
+ struct ucall uc;
+
+ TEST_ASSERT(run->exit_reason == KVM_EXIT_IO,
+ "Unexpected exit reason: %u (%s),\n",
+ run->exit_reason, exit_reason_str(run->exit_reason));
+
+ switch (get_ucall(vcpu, &uc)) {
+ case UCALL_SYNC:
+ TEST_ASSERT(vector == uc.args[1],
+ "Expected L2 to ask for %d, got %ld", vector, uc.args[1]);
+ break;
+ case UCALL_DONE:
+ TEST_ASSERT(vector == -1,
+ "Expected L2 to ask for %d, L2 says it's done", vector);
+ break;
+ case UCALL_ABORT:
+ TEST_FAIL("%s at %s:%ld (0x%lx != 0x%lx)",
+ (const char *)uc.args[0], __FILE__, uc.args[1],
+ uc.args[2], uc.args[3]);
+ break;
+ default:
+ TEST_FAIL("Expected L2 to ask for %d, got unexpected ucall %lu", vector, uc.cmd);
+ }
+}
+
+static void queue_ss_exception(struct kvm_vcpu *vcpu, bool inject)
+{
+ struct kvm_vcpu_events events;
+
+ vcpu_events_get(vcpu, &events);
+
+ TEST_ASSERT(!events.exception.pending,
+ "Vector %d unexpectedlt pending", events.exception.nr);
+ TEST_ASSERT(!events.exception.injected,
+ "Vector %d unexpectedly injected", events.exception.nr);
+
+ events.flags = KVM_VCPUEVENT_VALID_PAYLOAD;
+ events.exception.pending = !inject;
+ events.exception.injected = inject;
+ events.exception.nr = SS_VECTOR;
+ events.exception.has_error_code = true;
+ events.exception.error_code = SS_ERROR_CODE;
+ vcpu_events_set(vcpu, &events);
+}
+
+/*
+ * Verify KVM_{G,S}ET_EVENTS play nice with pending vs. injected exceptions
+ * when an exception is being queued for L2. Specifically, verify that KVM
+ * honors L1 exception intercept controls when a #SS is pending/injected,
+ * triggers a #GP on vectoring the #SS, morphs to #DF if #GP isn't intercepted
+ * by L1, and finally causes (nested) SHUTDOWN if #DF isn't intercepted by L1.
+ */
+int main(int argc, char *argv[])
+{
+ vm_vaddr_t nested_test_data_gva;
+ struct kvm_vcpu_events events;
+ struct kvm_vcpu *vcpu;
+ struct kvm_vm *vm;
+
+ TEST_REQUIRE(kvm_has_cap(KVM_CAP_EXCEPTION_PAYLOAD));
+ TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_SVM) || kvm_cpu_has(X86_FEATURE_VMX));
+
+ vm = vm_create_with_one_vcpu(&vcpu, l1_guest_code);
+ vm_enable_cap(vm, KVM_CAP_EXCEPTION_PAYLOAD, -2ul);
+
+ if (kvm_cpu_has(X86_FEATURE_SVM))
+ vcpu_alloc_svm(vm, &nested_test_data_gva);
+ else
+ vcpu_alloc_vmx(vm, &nested_test_data_gva);
+
+ vcpu_args_set(vcpu, 1, nested_test_data_gva);
+
+ /* Run L1 => L2. L2 should sync and request #SS. */
+ vcpu_run(vcpu);
+ assert_ucall_vector(vcpu, SS_VECTOR);
+
+ /* Pend #SS and request immediate exit. #SS should still be pending. */
+ queue_ss_exception(vcpu, false);
+ vcpu->run->immediate_exit = true;
+ vcpu_run_complete_io(vcpu);
+
+ /* Verify the pending events comes back out the same as it went in. */
+ vcpu_events_get(vcpu, &events);
+ ASSERT_EQ(events.flags & KVM_VCPUEVENT_VALID_PAYLOAD,
+ KVM_VCPUEVENT_VALID_PAYLOAD);
+ ASSERT_EQ(events.exception.pending, true);
+ ASSERT_EQ(events.exception.nr, SS_VECTOR);
+ ASSERT_EQ(events.exception.has_error_code, true);
+ ASSERT_EQ(events.exception.error_code, SS_ERROR_CODE);
+
+ /*
+ * Run for real with the pending #SS, L1 should get a VM-Exit due to
+ * #SS interception and re-enter L2 to request #GP (via injected #SS).
+ */
+ vcpu->run->immediate_exit = false;
+ vcpu_run(vcpu);
+ assert_ucall_vector(vcpu, GP_VECTOR);
+
+ /*
+ * Inject #SS, the #SS should bypass interception and cause #GP, which
+ * L1 should intercept before KVM morphs it to #DF. L1 should then
+ * disable #GP interception and run L2 to request #DF (via #SS => #GP).
+ */
+ queue_ss_exception(vcpu, true);
+ vcpu_run(vcpu);
+ assert_ucall_vector(vcpu, DF_VECTOR);
+
+ /*
+ * Inject #SS, the #SS should bypass interception and cause #GP, which
+ * L1 is no longer interception, and so should see a #DF VM-Exit. L1
+ * should then signal that is done.
+ */
+ queue_ss_exception(vcpu, true);
+ vcpu_run(vcpu);
+ assert_ucall_vector(vcpu, FAKE_TRIPLE_FAULT_VECTOR);
+
+ /*
+ * Inject #SS yet again. L1 is not intercepting #GP or #DF, and so
+ * should see nested TRIPLE_FAULT / SHUTDOWN.
+ */
+ queue_ss_exception(vcpu, true);
+ vcpu_run(vcpu);
+ assert_ucall_vector(vcpu, -1);
+
+ kvm_vm_free(vm);
+}