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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/x86/kvm/vmx/vmenter.S
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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/x86/kvm/vmx/vmenter.S')
-rw-r--r--arch/x86/kvm/vmx/vmenter.S354
1 files changed, 354 insertions, 0 deletions
diff --git a/arch/x86/kvm/vmx/vmenter.S b/arch/x86/kvm/vmx/vmenter.S
new file mode 100644
index 000000000..766c6b3ef
--- /dev/null
+++ b/arch/x86/kvm/vmx/vmenter.S
@@ -0,0 +1,354 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#include <linux/linkage.h>
+#include <asm/asm.h>
+#include <asm/bitsperlong.h>
+#include <asm/kvm_vcpu_regs.h>
+#include <asm/nospec-branch.h>
+#include <asm/percpu.h>
+#include <asm/segment.h>
+#include "kvm-asm-offsets.h"
+#include "run_flags.h"
+
+#define WORD_SIZE (BITS_PER_LONG / 8)
+
+#define VCPU_RAX __VCPU_REGS_RAX * WORD_SIZE
+#define VCPU_RCX __VCPU_REGS_RCX * WORD_SIZE
+#define VCPU_RDX __VCPU_REGS_RDX * WORD_SIZE
+#define VCPU_RBX __VCPU_REGS_RBX * WORD_SIZE
+/* Intentionally omit RSP as it's context switched by hardware */
+#define VCPU_RBP __VCPU_REGS_RBP * WORD_SIZE
+#define VCPU_RSI __VCPU_REGS_RSI * WORD_SIZE
+#define VCPU_RDI __VCPU_REGS_RDI * WORD_SIZE
+
+#ifdef CONFIG_X86_64
+#define VCPU_R8 __VCPU_REGS_R8 * WORD_SIZE
+#define VCPU_R9 __VCPU_REGS_R9 * WORD_SIZE
+#define VCPU_R10 __VCPU_REGS_R10 * WORD_SIZE
+#define VCPU_R11 __VCPU_REGS_R11 * WORD_SIZE
+#define VCPU_R12 __VCPU_REGS_R12 * WORD_SIZE
+#define VCPU_R13 __VCPU_REGS_R13 * WORD_SIZE
+#define VCPU_R14 __VCPU_REGS_R14 * WORD_SIZE
+#define VCPU_R15 __VCPU_REGS_R15 * WORD_SIZE
+#endif
+
+.section .noinstr.text, "ax"
+
+/**
+ * __vmx_vcpu_run - Run a vCPU via a transition to VMX guest mode
+ * @vmx: struct vcpu_vmx *
+ * @regs: unsigned long * (to guest registers)
+ * @flags: VMX_RUN_VMRESUME: use VMRESUME instead of VMLAUNCH
+ * VMX_RUN_SAVE_SPEC_CTRL: save guest SPEC_CTRL into vmx->spec_ctrl
+ *
+ * Returns:
+ * 0 on VM-Exit, 1 on VM-Fail
+ */
+SYM_FUNC_START(__vmx_vcpu_run)
+ push %_ASM_BP
+ mov %_ASM_SP, %_ASM_BP
+#ifdef CONFIG_X86_64
+ push %r15
+ push %r14
+ push %r13
+ push %r12
+#else
+ push %edi
+ push %esi
+#endif
+ push %_ASM_BX
+
+ /* Save @vmx for SPEC_CTRL handling */
+ push %_ASM_ARG1
+
+ /* Save @flags for SPEC_CTRL handling */
+ push %_ASM_ARG3
+
+ /*
+ * Save @regs, _ASM_ARG2 may be modified by vmx_update_host_rsp() and
+ * @regs is needed after VM-Exit to save the guest's register values.
+ */
+ push %_ASM_ARG2
+
+ /* Copy @flags to BL, _ASM_ARG3 is volatile. */
+ mov %_ASM_ARG3B, %bl
+
+ lea (%_ASM_SP), %_ASM_ARG2
+ call vmx_update_host_rsp
+
+ ALTERNATIVE "jmp .Lspec_ctrl_done", "", X86_FEATURE_MSR_SPEC_CTRL
+
+ /*
+ * SPEC_CTRL handling: if the guest's SPEC_CTRL value differs from the
+ * host's, write the MSR.
+ *
+ * IMPORTANT: To avoid RSB underflow attacks and any other nastiness,
+ * there must not be any returns or indirect branches between this code
+ * and vmentry.
+ */
+ mov 2*WORD_SIZE(%_ASM_SP), %_ASM_DI
+ movl VMX_spec_ctrl(%_ASM_DI), %edi
+ movl PER_CPU_VAR(x86_spec_ctrl_current), %esi
+ cmp %edi, %esi
+ je .Lspec_ctrl_done
+ mov $MSR_IA32_SPEC_CTRL, %ecx
+ xor %edx, %edx
+ mov %edi, %eax
+ wrmsr
+
+.Lspec_ctrl_done:
+
+ /*
+ * Since vmentry is serializing on affected CPUs, there's no need for
+ * an LFENCE to stop speculation from skipping the wrmsr.
+ */
+
+ /* Load @regs to RAX. */
+ mov (%_ASM_SP), %_ASM_AX
+
+ /* Check if vmlaunch or vmresume is needed */
+ testb $VMX_RUN_VMRESUME, %bl
+
+ /* Load guest registers. Don't clobber flags. */
+ mov VCPU_RCX(%_ASM_AX), %_ASM_CX
+ mov VCPU_RDX(%_ASM_AX), %_ASM_DX
+ mov VCPU_RBX(%_ASM_AX), %_ASM_BX
+ mov VCPU_RBP(%_ASM_AX), %_ASM_BP
+ mov VCPU_RSI(%_ASM_AX), %_ASM_SI
+ mov VCPU_RDI(%_ASM_AX), %_ASM_DI
+#ifdef CONFIG_X86_64
+ mov VCPU_R8 (%_ASM_AX), %r8
+ mov VCPU_R9 (%_ASM_AX), %r9
+ mov VCPU_R10(%_ASM_AX), %r10
+ mov VCPU_R11(%_ASM_AX), %r11
+ mov VCPU_R12(%_ASM_AX), %r12
+ mov VCPU_R13(%_ASM_AX), %r13
+ mov VCPU_R14(%_ASM_AX), %r14
+ mov VCPU_R15(%_ASM_AX), %r15
+#endif
+ /* Load guest RAX. This kills the @regs pointer! */
+ mov VCPU_RAX(%_ASM_AX), %_ASM_AX
+
+ /* Check EFLAGS.ZF from 'testb' above */
+ jz .Lvmlaunch
+
+ /*
+ * After a successful VMRESUME/VMLAUNCH, control flow "magically"
+ * resumes below at 'vmx_vmexit' due to the VMCS HOST_RIP setting.
+ * So this isn't a typical function and objtool needs to be told to
+ * save the unwind state here and restore it below.
+ */
+ UNWIND_HINT_SAVE
+
+/*
+ * If VMRESUME/VMLAUNCH and corresponding vmexit succeed, execution resumes at
+ * the 'vmx_vmexit' label below.
+ */
+.Lvmresume:
+ vmresume
+ jmp .Lvmfail
+
+.Lvmlaunch:
+ vmlaunch
+ jmp .Lvmfail
+
+ _ASM_EXTABLE(.Lvmresume, .Lfixup)
+ _ASM_EXTABLE(.Lvmlaunch, .Lfixup)
+
+SYM_INNER_LABEL(vmx_vmexit, SYM_L_GLOBAL)
+
+ /* Restore unwind state from before the VMRESUME/VMLAUNCH. */
+ UNWIND_HINT_RESTORE
+ ENDBR
+
+ /* Temporarily save guest's RAX. */
+ push %_ASM_AX
+
+ /* Reload @regs to RAX. */
+ mov WORD_SIZE(%_ASM_SP), %_ASM_AX
+
+ /* Save all guest registers, including RAX from the stack */
+ pop VCPU_RAX(%_ASM_AX)
+ mov %_ASM_CX, VCPU_RCX(%_ASM_AX)
+ mov %_ASM_DX, VCPU_RDX(%_ASM_AX)
+ mov %_ASM_BX, VCPU_RBX(%_ASM_AX)
+ mov %_ASM_BP, VCPU_RBP(%_ASM_AX)
+ mov %_ASM_SI, VCPU_RSI(%_ASM_AX)
+ mov %_ASM_DI, VCPU_RDI(%_ASM_AX)
+#ifdef CONFIG_X86_64
+ mov %r8, VCPU_R8 (%_ASM_AX)
+ mov %r9, VCPU_R9 (%_ASM_AX)
+ mov %r10, VCPU_R10(%_ASM_AX)
+ mov %r11, VCPU_R11(%_ASM_AX)
+ mov %r12, VCPU_R12(%_ASM_AX)
+ mov %r13, VCPU_R13(%_ASM_AX)
+ mov %r14, VCPU_R14(%_ASM_AX)
+ mov %r15, VCPU_R15(%_ASM_AX)
+#endif
+
+ /* Clear return value to indicate VM-Exit (as opposed to VM-Fail). */
+ xor %ebx, %ebx
+
+.Lclear_regs:
+ /* Discard @regs. The register is irrelevant, it just can't be RBX. */
+ pop %_ASM_AX
+
+ /*
+ * Clear all general purpose registers except RSP and RBX to prevent
+ * speculative use of the guest's values, even those that are reloaded
+ * via the stack. In theory, an L1 cache miss when restoring registers
+ * could lead to speculative execution with the guest's values.
+ * Zeroing XORs are dirt cheap, i.e. the extra paranoia is essentially
+ * free. RSP and RBX are exempt as RSP is restored by hardware during
+ * VM-Exit and RBX is explicitly loaded with 0 or 1 to hold the return
+ * value.
+ */
+ xor %eax, %eax
+ xor %ecx, %ecx
+ xor %edx, %edx
+ xor %ebp, %ebp
+ xor %esi, %esi
+ xor %edi, %edi
+#ifdef CONFIG_X86_64
+ xor %r8d, %r8d
+ xor %r9d, %r9d
+ xor %r10d, %r10d
+ xor %r11d, %r11d
+ xor %r12d, %r12d
+ xor %r13d, %r13d
+ xor %r14d, %r14d
+ xor %r15d, %r15d
+#endif
+
+ /*
+ * IMPORTANT: RSB filling and SPEC_CTRL handling must be done before
+ * the first unbalanced RET after vmexit!
+ *
+ * For retpoline or IBRS, RSB filling is needed to prevent poisoned RSB
+ * entries and (in some cases) RSB underflow.
+ *
+ * eIBRS has its own protection against poisoned RSB, so it doesn't
+ * need the RSB filling sequence. But it does need to be enabled, and a
+ * single call to retire, before the first unbalanced RET.
+ */
+
+ FILL_RETURN_BUFFER %_ASM_CX, RSB_CLEAR_LOOPS, X86_FEATURE_RSB_VMEXIT,\
+ X86_FEATURE_RSB_VMEXIT_LITE
+
+ pop %_ASM_ARG2 /* @flags */
+ pop %_ASM_ARG1 /* @vmx */
+
+ call vmx_spec_ctrl_restore_host
+
+ /* Put return value in AX */
+ mov %_ASM_BX, %_ASM_AX
+
+ pop %_ASM_BX
+#ifdef CONFIG_X86_64
+ pop %r12
+ pop %r13
+ pop %r14
+ pop %r15
+#else
+ pop %esi
+ pop %edi
+#endif
+ pop %_ASM_BP
+ RET
+
+.Lfixup:
+ cmpb $0, kvm_rebooting
+ jne .Lvmfail
+ ud2
+.Lvmfail:
+ /* VM-Fail: set return value to 1 */
+ mov $1, %_ASM_BX
+ jmp .Lclear_regs
+
+SYM_FUNC_END(__vmx_vcpu_run)
+
+
+.section .text, "ax"
+
+#ifndef CONFIG_CC_HAS_ASM_GOTO_OUTPUT
+/**
+ * vmread_error_trampoline - Trampoline from inline asm to vmread_error()
+ * @field: VMCS field encoding that failed
+ * @fault: %true if the VMREAD faulted, %false if it failed
+
+ * Save and restore volatile registers across a call to vmread_error(). Note,
+ * all parameters are passed on the stack.
+ */
+SYM_FUNC_START(vmread_error_trampoline)
+ push %_ASM_BP
+ mov %_ASM_SP, %_ASM_BP
+
+ push %_ASM_AX
+ push %_ASM_CX
+ push %_ASM_DX
+#ifdef CONFIG_X86_64
+ push %rdi
+ push %rsi
+ push %r8
+ push %r9
+ push %r10
+ push %r11
+#endif
+
+ /* Load @field and @fault to arg1 and arg2 respectively. */
+ mov 3*WORD_SIZE(%_ASM_BP), %_ASM_ARG2
+ mov 2*WORD_SIZE(%_ASM_BP), %_ASM_ARG1
+
+ call vmread_error
+
+ /* Zero out @fault, which will be popped into the result register. */
+ _ASM_MOV $0, 3*WORD_SIZE(%_ASM_BP)
+
+#ifdef CONFIG_X86_64
+ pop %r11
+ pop %r10
+ pop %r9
+ pop %r8
+ pop %rsi
+ pop %rdi
+#endif
+ pop %_ASM_DX
+ pop %_ASM_CX
+ pop %_ASM_AX
+ pop %_ASM_BP
+
+ RET
+SYM_FUNC_END(vmread_error_trampoline)
+#endif
+
+SYM_FUNC_START(vmx_do_interrupt_nmi_irqoff)
+ /*
+ * Unconditionally create a stack frame, getting the correct RSP on the
+ * stack (for x86-64) would take two instructions anyways, and RBP can
+ * be used to restore RSP to make objtool happy (see below).
+ */
+ push %_ASM_BP
+ mov %_ASM_SP, %_ASM_BP
+
+#ifdef CONFIG_X86_64
+ /*
+ * Align RSP to a 16-byte boundary (to emulate CPU behavior) before
+ * creating the synthetic interrupt stack frame for the IRQ/NMI.
+ */
+ and $-16, %rsp
+ push $__KERNEL_DS
+ push %rbp
+#endif
+ pushf
+ push $__KERNEL_CS
+ CALL_NOSPEC _ASM_ARG1
+
+ /*
+ * "Restore" RSP from RBP, even though IRET has already unwound RSP to
+ * the correct value. objtool doesn't know the callee will IRET and,
+ * without the explicit restore, thinks the stack is getting walloped.
+ * Using an unwind hint is problematic due to x86-64's dynamic alignment.
+ */
+ mov %_ASM_BP, %_ASM_SP
+ pop %_ASM_BP
+ RET
+SYM_FUNC_END(vmx_do_interrupt_nmi_irqoff)