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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/kernel/static_call.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/x86/kernel/static_call.c')
-rw-r--r--arch/x86/kernel/static_call.c201
1 files changed, 201 insertions, 0 deletions
diff --git a/arch/x86/kernel/static_call.c b/arch/x86/kernel/static_call.c
new file mode 100644
index 000000000..b70670a98
--- /dev/null
+++ b/arch/x86/kernel/static_call.c
@@ -0,0 +1,201 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/static_call.h>
+#include <linux/memory.h>
+#include <linux/bug.h>
+#include <asm/text-patching.h>
+
+enum insn_type {
+ CALL = 0, /* site call */
+ NOP = 1, /* site cond-call */
+ JMP = 2, /* tramp / site tail-call */
+ RET = 3, /* tramp / site cond-tail-call */
+ JCC = 4,
+};
+
+/*
+ * ud1 %esp, %ecx - a 3 byte #UD that is unique to trampolines, chosen such
+ * that there is no false-positive trampoline identification while also being a
+ * speculation stop.
+ */
+static const u8 tramp_ud[] = { 0x0f, 0xb9, 0xcc };
+
+/*
+ * cs cs cs xorl %eax, %eax - a single 5 byte instruction that clears %[er]ax
+ */
+static const u8 xor5rax[] = { 0x2e, 0x2e, 0x2e, 0x31, 0xc0 };
+
+static const u8 retinsn[] = { RET_INSN_OPCODE, 0xcc, 0xcc, 0xcc, 0xcc };
+
+static u8 __is_Jcc(u8 *insn) /* Jcc.d32 */
+{
+ u8 ret = 0;
+
+ if (insn[0] == 0x0f) {
+ u8 tmp = insn[1];
+ if ((tmp & 0xf0) == 0x80)
+ ret = tmp;
+ }
+
+ return ret;
+}
+
+extern void __static_call_return(void);
+
+asm (".global __static_call_return\n\t"
+ ".type __static_call_return, @function\n\t"
+ ASM_FUNC_ALIGN "\n\t"
+ "__static_call_return:\n\t"
+ ANNOTATE_NOENDBR
+ ANNOTATE_RETPOLINE_SAFE
+ "ret; int3\n\t"
+ ".size __static_call_return, . - __static_call_return \n\t");
+
+static void __ref __static_call_transform(void *insn, enum insn_type type,
+ void *func, bool modinit)
+{
+ const void *emulate = NULL;
+ int size = CALL_INSN_SIZE;
+ const void *code;
+ u8 op, buf[6];
+
+ if ((type == JMP || type == RET) && (op = __is_Jcc(insn)))
+ type = JCC;
+
+ switch (type) {
+ case CALL:
+ func = callthunks_translate_call_dest(func);
+ code = text_gen_insn(CALL_INSN_OPCODE, insn, func);
+ if (func == &__static_call_return0) {
+ emulate = code;
+ code = &xor5rax;
+ }
+
+ break;
+
+ case NOP:
+ code = x86_nops[5];
+ break;
+
+ case JMP:
+ code = text_gen_insn(JMP32_INSN_OPCODE, insn, func);
+ break;
+
+ case RET:
+ if (cpu_feature_enabled(X86_FEATURE_RETHUNK))
+ code = text_gen_insn(JMP32_INSN_OPCODE, insn, x86_return_thunk);
+ else
+ code = &retinsn;
+ break;
+
+ case JCC:
+ if (!func) {
+ func = __static_call_return;
+ if (cpu_feature_enabled(X86_FEATURE_RETHUNK))
+ func = x86_return_thunk;
+ }
+
+ buf[0] = 0x0f;
+ __text_gen_insn(buf+1, op, insn+1, func, 5);
+ code = buf;
+ size = 6;
+
+ break;
+ }
+
+ if (memcmp(insn, code, size) == 0)
+ return;
+
+ if (system_state == SYSTEM_BOOTING || modinit)
+ return text_poke_early(insn, code, size);
+
+ text_poke_bp(insn, code, size, emulate);
+}
+
+static void __static_call_validate(u8 *insn, bool tail, bool tramp)
+{
+ u8 opcode = insn[0];
+
+ if (tramp && memcmp(insn+5, tramp_ud, 3)) {
+ pr_err("trampoline signature fail");
+ BUG();
+ }
+
+ if (tail) {
+ if (opcode == JMP32_INSN_OPCODE ||
+ opcode == RET_INSN_OPCODE ||
+ __is_Jcc(insn))
+ return;
+ } else {
+ if (opcode == CALL_INSN_OPCODE ||
+ !memcmp(insn, x86_nops[5], 5) ||
+ !memcmp(insn, xor5rax, 5))
+ return;
+ }
+
+ /*
+ * If we ever trigger this, our text is corrupt, we'll probably not live long.
+ */
+ pr_err("unexpected static_call insn opcode 0x%x at %pS\n", opcode, insn);
+ BUG();
+}
+
+static inline enum insn_type __sc_insn(bool null, bool tail)
+{
+ /*
+ * Encode the following table without branches:
+ *
+ * tail null insn
+ * -----+-------+------
+ * 0 | 0 | CALL
+ * 0 | 1 | NOP
+ * 1 | 0 | JMP
+ * 1 | 1 | RET
+ */
+ return 2*tail + null;
+}
+
+void arch_static_call_transform(void *site, void *tramp, void *func, bool tail)
+{
+ mutex_lock(&text_mutex);
+
+ if (tramp) {
+ __static_call_validate(tramp, true, true);
+ __static_call_transform(tramp, __sc_insn(!func, true), func, false);
+ }
+
+ if (IS_ENABLED(CONFIG_HAVE_STATIC_CALL_INLINE) && site) {
+ __static_call_validate(site, tail, false);
+ __static_call_transform(site, __sc_insn(!func, tail), func, false);
+ }
+
+ mutex_unlock(&text_mutex);
+}
+EXPORT_SYMBOL_GPL(arch_static_call_transform);
+
+#ifdef CONFIG_RETHUNK
+/*
+ * This is called by apply_returns() to fix up static call trampolines,
+ * specifically ARCH_DEFINE_STATIC_CALL_NULL_TRAMP which is recorded as
+ * having a return trampoline.
+ *
+ * The problem is that static_call() is available before determining
+ * X86_FEATURE_RETHUNK and, by implication, running alternatives.
+ *
+ * This means that __static_call_transform() above can have overwritten the
+ * return trampoline and we now need to fix things up to be consistent.
+ */
+bool __static_call_fixup(void *tramp, u8 op, void *dest)
+{
+ if (memcmp(tramp+5, tramp_ud, 3)) {
+ /* Not a trampoline site, not our problem. */
+ return false;
+ }
+
+ mutex_lock(&text_mutex);
+ if (op == RET_INSN_OPCODE || dest == &__x86_return_thunk)
+ __static_call_transform(tramp, RET, NULL, true);
+ mutex_unlock(&text_mutex);
+
+ return true;
+}
+#endif