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authorLinus Torvalds <torvalds@linux-foundation.org>2026-10-23 13:08:49 -1000
committerLinus Torvalds <torvalds@linux-foundation.org>2026-10-23 13:08:49 -1000
commit55fbedcec622a943cb09a969aef1ddcba87ee40a (patch)
tree99bf57398ef32396f831f31efffb5d917ce22e0c /tools/include/uapi/linux/btf.h
parent90b754d40117b2889bbe847ce7bb4dcf968e7cb8 (diff)
parentb116ac6087541d3d98031e786adbe9c733cd6df3 (diff)
Merge tag 'bpf-next-7.4' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Pull bpf updates from Alexei Starovoitov: "Major changes: - Introduce scalar evolution (SCEV) analysis in the verifier. It infers how registers and stack slots change in a loop and lets the verifier check bounded loops with induction variables as ranges instead of walking every iteration. The number of processed insns drops ten fold in programs with loops (Eduard Zingerman) - Add 'callx' instruction: indirect call of a static BPF subprogram. The address is taken with ld_imm64 or loaded from read-only data. Supported by x86-64, arm64 and riscv64 JITs (Alexei Starovoitov, Pu Lehui) - Add unwind_goto and unwind_exit instructions, so that Rust panic or C++ exception can run destructors of every frame it passes through. The normal path is free of unwind code. Supported by x86-64 and arm64 JITs (Alexei Starovoitov) - Support programs compiled by rust-bpf: treat load and store through a number as arena access with BPF_F_ARENA_SCALAR, accept rust names in BTF (Alexei Starovoitov) - Raise BPF program stack size from 512 bytes to 2 KiB on x86-64 and arm64 (Kumar Kartikeya Dwivedi) - Support struct, union and __int128 up to 16 bytes passed and returned by value in BPF subprograms and kfuncs, and fix x86-64 and arm64 trampolines for such arguments (Yonghong Song) - Introduce a common way to attach struct_ops to a cgroup via bpf_link. bpf_tcp_ops is the first user and mirrors TCP sock_ops callbacks (Martin KaFai Lau, Amery Hung) - Describe inlined functions in BTF. New kinds tell where the inline sites are and how to fetch the arguments there. CONFIG_DEBUG_INFO_BTF_INLINE keeps it apart from the main BTF in .BTF.inline section or in btf_vmlinux_inline.ko (Alan Maguire) - Fix many memory safety, lifetime and locking bugs in BPF core, verifier, iterators, local storage, dynptr, devmap, cpumap and seg6local (Josef Bacik, Alexei Starovoitov) - Diff stat is dominated by selftests and by removal of lib/test_bpf.c. Its 16k lines of instruction tests were converted to BPF selftests that BPF CI runs on every architecture it covers (Daniel Borkmann) Other features and fixes: - Add KASAN checks to memory accesses of JITed programs on x86-64 (Alexis Lothoré) - Complete unification of helper, kfunc and subprog argument checks in the verifier (Amery Hung) - Add bpf_copy_from_user_mm[_str]() kfuncs (Anastasios Papagiannis) - Various features and fixes (Daniel Borkmann): - Add .bpf keyring for program signature verification, modelled after dm-verity keyring, and support ML-DSA in signing tools - Emit shorter and faster code in x86-64 JIT for patterns that LLVM generates - Fix various issues in gotox handling - Let BPF LSM set xattrs at inode creation with bpf_inode_init_xattr() (David Windsor, Daniel Borkmann) - Use sleepable page allocation in sleepable arena paths. Fix races between arena free, allocation and user page fault (Emil Tsalapatis) - Switch BPF crypto from lskcipher to AES-CBC and AES-ECB libraries (Eric Biggers) - Add bpf_proactive_reclaim() kfunc (Hui Zhu) - Render decl_tags in libbpf btf_dump and add tests for bpftool C dump (Ihor Solodrai) - Speed up tracing_multi attach on x86 (Jiri Olsa) - Various features and fixes (Kumar Kartikeya Dwivedi): - Add BPF_PROG_STREAM_OPEN command to read BPF streams through a file descriptor with poll support - Let kernel structs publish arena pointers with __arena type tag - Fix __uninit kfunc output buffers and fastcall rewrite with indirect stack accesses - Refuse CO-RE relocations for signed programs - Add enqueue_rcvq and dequeue_rcvq hooks to bpf_tcp_ops to adjust sk_rcvlowat and avoid unnecessary wakeups (Kuniyuki Iwashima) - Add bpf_ksock_sendto() kfunc and allow ksock connect and send from bpf_wq (Mahe Tardy) - Fix racy plt target update in arm64 bpf_arch_text_poke() (Matthew Wood) - Restructure BPF selftests Makefile as a layered build (Mykola Lysenko) - Speed up hash map lookups for u32 and u64 keys (Mykyta Yatsenko) - Add signed div/mod, movsx, bswap and gotol to MIPS JITs, signed div/mod to parisc JITs (Nicholas Dudar, Johan Almbladh) - Fix stack overflow in build ID parser on 32-bit (Nickolai Zeldovich) - Add stack arguments, signed arena loads and gotox to riscv64 JIT. Pu Lehui is now co-maintainer of riscv BPF JITs (Pu Lehui, Chen Pei, Feng Jiang) - Add bpf_call_rcu() and bpf_call_rcu_tasks_trace() kfuncs. Support fetching and/or/xor atomics in arena on x86-64 (Puranjay Mohan) - Fix flaky selftests, selftests with clang 23 and bpf-gcc (Qiliang Yuan, KaFai Wan, Vineet Gupta) - Fix builds broken by fatal resolve_btfids warnings, BTF generation on ARC, and define arch_cmpxchg_local() on arc, hexagon and openrisc (Sasha Levin) - Reduce memory use of hash maps by up to 50% per element (T.J. Mercier) - Mark pointer fields of sched_ext ops arguments as trusted (Tejun Heo) - Remove legacy bpf_asm, bpf_dbg and bpf_jit_disasm tools (Xia Yan) - Fix index overflow in queue and stack maps, arena range tree after allocation failure, tail call loop after freplace detach, lost signal in bpf_send_signal() (Yuan Chen) - Many more fixes and cleanups" * tag 'bpf-next-7.4' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (660 commits) selftests/bpf: Time tc_edt from its first packet with data selftests/bpf: Test unwind_exit of an exception callback selftests/bpf: Tests for 32-bit scalar evolution bounds computation bpf: Reject unwind_goto and unwind_exit in offloaded progs bpf: Support 32-bit linear scalar evolution bpf: Make unwind_exit of an exception callback exit in JITs selftests/bpf: Test forbidden bpf_ksock_sendto() LSM attach selftests/bpf: Test ksock sendto() bpf: Add bpf_ksock_sendto() kfunc selftests/bpf: Test unwinding from R0: R2 subprog selftests/bpf: Add a C++ prog with exceptions selftests/bpf: Add tests for unwind_goto and unwind_exit bpf, arm64: Support unwind_goto and unwind_exit bpf, x86: Support unwind_goto and unwind_exit bpf: Add unwind_goto and unwind_exit insns tools/bpf: Remove legacy BPF tools bpf: Annotate data races on bpf_lru_node type selftests/bpf: Add arena allocation race tests bpf: Fix arena race between page free and alloc leading to incoherency bpf: Revalidate faulted arena pages before installing user mappings ...
Diffstat (limited to 'tools/include/uapi/linux/btf.h')
-rw-r--r--tools/include/uapi/linux/btf.h83
1 files changed, 80 insertions, 3 deletions
diff --git a/tools/include/uapi/linux/btf.h b/tools/include/uapi/linux/btf.h
index 618167cab4e6..11d65871d163 100644
--- a/tools/include/uapi/linux/btf.h
+++ b/tools/include/uapi/linux/btf.h
@@ -54,8 +54,8 @@ struct btf_type {
* decl_tag and type_tag
*/
__u32 info;
- /* "size" is used by INT, ENUM, STRUCT, UNION, DATASEC and ENUM64.
- * "size" tells the size of the type it is describing.
+ /* "size" is used by INT, ENUM, STRUCT, UNION, DATASEC, ENUM64
+ * and LOC_PARAM. "size" tells the size of the type it is describing.
*
* "type" is used by PTR, TYPEDEF, VOLATILE, CONST, RESTRICT,
* FUNC, FUNC_PROTO, VAR, DECL_TAG and TYPE_TAG.
@@ -92,7 +92,9 @@ enum {
BTF_KIND_DECL_TAG = 17, /* Decl Tag */
BTF_KIND_TYPE_TAG = 18, /* Type Tag */
BTF_KIND_ENUM64 = 19, /* Enumeration up to 64-bit values */
-
+ BTF_KIND_LOC_PARAM = 20, /* Location parameter information */
+ BTF_KIND_LOC_PROTO = 21, /* Location prototype for site */
+ BTF_KIND_LOCSEC = 22, /* Location section */
NR_BTF_KINDS,
BTF_KIND_MAX = NR_BTF_KINDS - 1,
};
@@ -212,4 +214,79 @@ struct btf_enum64 {
__u32 val_hi32;
};
+/*
+ * BTF_KIND_LOC_PARAM is followed by a single "struct btf_loc_param"
+ * that contains flags specifying the contents of the vlen-specified
+ * number of 4-byte values that follow.
+ */
+struct btf_loc_param {
+ __u32 flags;
+ __u32 values[];
+};
+
+/*
+ * The combination of size, vlen and flags gives us the means to interpret
+ * the following vlen-specified set of 4-byte values:
+ *
+ * - a BTF_LOC_PARAM_CONST is a constant value; combination
+ * of size, vlen and _SIGNED flag determines it. If the value requires
+ * 64 bits it is stored in {lo,hi} order.
+ * - a BTF_LOC_PARAM_ADDR|BTF_LOC_PARAM_CONST is an address that should be
+ * normalized with respect to kernel/module base address.
+ * - a BTF_LOC_PARAM_REG with vlen 1 is a simple register number;
+ * with vlen 2 it is a multi-register parameter. Register numbers are
+ * numbers derived from DW_OP_reg values, i.e. 0 is DW_OP_reg0; since
+ * DW_OP_fbreg has its own special DW_OP_value and DW_OP_regx can refer
+ * to an arbitrary register number, we reserve BTF_LOC_PARAM_FBREG for
+ * the frame base register to avoid collisions.
+ * - a _REG | OFFSET describes an address without dereferencing it.
+ * - a _REG | DEREF with vlen 1 dereferences the value in the register
+ * number specified.
+ * - a REG | DEREF | OFFSET with vlen > 1 specifies the register number
+ * in the first 4-byte value and the offset in the remainder.
+ * In the case of REG and OFFSET combinations, the OFFSET has the width
+ * of the value words while the type size describes the represented parameter,
+ * so for example a REG | DEREF | OFFSET with size 8 and vlen 2 would be
+ * an 8-byte register dereference with signed 4-byte offset, since the vlen 2
+ * values consist of a register value and the signed value.
+ */
+enum btf_loc_param_flags {
+ BTF_LOC_PARAM_SIGNED = 0x1,
+ BTF_LOC_PARAM_CONST = 0x2,
+ BTF_LOC_PARAM_ADDR = 0x4,
+ BTF_LOC_PARAM_REG = 0x8,
+ BTF_LOC_PARAM_DEREF = 0x10,
+ BTF_LOC_PARAM_OFFSET = 0x20,
+};
+
+enum {
+ BTF_LOC_PARAM_FBREG = 0xffffffff
+};
+
+/*
+ * BTF_KIND_LOC_PROTO specifies location prototypes; i.e. how locations relate
+ * to parameters; a struct btf_type of BTF_KIND_LOC_PROTO is followed by a
+ * vlen-specified number of __u32 BTF type ids which specify the associated
+ * BTF_KIND_LOC_PARAM for each function parameter associated with the
+ * location. The type should either be 0 (no location info) or point at
+ * a BTF_KIND_LOC_PARAM.
+ */
+
+/*
+ * BTF_KIND_LOCSEC consists of vlen-specified number of "struct btf_loc"
+ * containing location site-specific information for a specific ELF section;
+ * for example locations in ".text" are in a LOCSEC named "inline.text".
+ *
+ * - function (func)
+ * - location prototype type id (loc_proto)
+ * - address offset (offset) relative to the runtime base address of the
+ * ELF section associated with the LOCSEC
+ */
+
+struct btf_loc {
+ __u32 func;
+ __u32 loc_proto;
+ __u32 offset;
+};
+
#endif /* _UAPI__LINUX_BTF_H__ */