From 5febf432df1cfa5b25d99b54c32103fafbdd0eb9 Mon Sep 17 00:00:00 2001 From: Miguel Ojeda Date: Sun, 16 Aug 2026 15:32:33 +0200 Subject: kbuild: rust: keep Rust objects out of Clang LTO with inline helpers Under `CONFIG_LTO_CLANG` + `CONFIG_RUST_INLINE_HELPERS`, one may hit `objtool` errors such as: vmlinux.o: error: objtool: _R..._3Gsp4boot+0xd6a: can't find jump dest instruction at .text._R..._3Gsp4boot+0x1dfd The reason is that in such builds, the Clang invocation that compiles the combined Rust plus helpers bitcode emits LLVM bitcode (again) -- the final code generation happens in the linker's LTO step, which the `-mllvm` trap options passed to Clang do not reach. This, in turn, means that unreachable traps are missing, and the impossible paths do not merely fallthrough to the next symbol, but past the end of their own section, since LTO builds place each function in its own section. Thus filter `CC_FLAGS_LTO` out of the Clang invocation, so that it always emits machine code directly, with the traps in place. Assisted-by: LLM Cc: Gary Guo Cc: Boqun Feng Cc: Alice Ryhl Cc: Matthew Maurer Cc: Josh Poimboeuf Cc: Peter Zijlstra Cc: stable@vger.kernel.org Fixes: 3a2486cc1da5 ("kbuild: rust: provide an option to inline C helpers into Rust") Acked-by: Gary Guo Link: https://patch.msgid.link/20260816133233.197500-2-ojeda@kernel.org Signed-off-by: Miguel Ojeda --- include/net/inetpeer.h | 150 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 150 insertions(+) create mode 100644 include/net/inetpeer.h (limited to 'include/net/inetpeer.h') diff --git a/include/net/inetpeer.h b/include/net/inetpeer.h new file mode 100644 index 000000000..f475757da --- /dev/null +++ b/include/net/inetpeer.h @@ -0,0 +1,150 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * INETPEER - A storage for permanent information about peers + * + * Authors: Andrey V. Savochkin + */ + +#ifndef _NET_INETPEER_H +#define _NET_INETPEER_H + +#include +#include +#include +#include +#include +#include +#include + +/* IPv4 address key for cache lookups */ +struct ipv4_addr_key { + __be32 addr; + int vif; +}; + +#define INETPEER_MAXKEYSZ (sizeof(struct in6_addr) / sizeof(u32)) + +struct inetpeer_addr { + union { + struct ipv4_addr_key a4; + struct in6_addr a6; + u32 key[INETPEER_MAXKEYSZ]; + }; + __u16 family; +}; + +struct inet_peer { + struct rb_node rb_node; + struct inetpeer_addr daddr; + + u32 metrics[RTAX_MAX]; + u32 rate_tokens; /* rate limiting for ICMP */ + u32 n_redirects; + unsigned long rate_last; + /* + * Once inet_peer is queued for deletion (refcnt == 0), following field + * is not available: rid + * We can share memory with rcu_head to help keep inet_peer small. + */ + union { + struct { + atomic_t rid; /* Frag reception counter */ + }; + struct rcu_head rcu; + }; + + /* following fields might be frequently dirtied */ + __u32 dtime; /* the time of last use of not referenced entries */ + refcount_t refcnt; +}; + +struct inet_peer_base { + struct rb_root rb_root; + seqlock_t lock; + int total; +}; + +void inet_peer_base_init(struct inet_peer_base *); + +void inet_initpeers(void) __init; + +#define INETPEER_METRICS_NEW (~(u32) 0) + +static inline void inetpeer_set_addr_v4(struct inetpeer_addr *iaddr, __be32 ip) +{ + iaddr->a4.addr = ip; + iaddr->a4.vif = 0; + iaddr->family = AF_INET; +} + +static inline __be32 inetpeer_get_addr_v4(struct inetpeer_addr *iaddr) +{ + return iaddr->a4.addr; +} + +static inline void inetpeer_set_addr_v6(struct inetpeer_addr *iaddr, + struct in6_addr *in6) +{ + iaddr->a6 = *in6; + iaddr->family = AF_INET6; +} + +static inline struct in6_addr *inetpeer_get_addr_v6(struct inetpeer_addr *iaddr) +{ + return &iaddr->a6; +} + +/* can be called with or without local BH being disabled */ +struct inet_peer *inet_getpeer(struct inet_peer_base *base, + const struct inetpeer_addr *daddr); + +static inline struct inet_peer *inet_getpeer_v4(struct inet_peer_base *base, + __be32 v4daddr, + int vif) +{ + struct inetpeer_addr daddr; + + daddr.a4.addr = v4daddr; + daddr.a4.vif = vif; + daddr.family = AF_INET; + return inet_getpeer(base, &daddr); +} + +static inline struct inet_peer *inet_getpeer_v6(struct inet_peer_base *base, + const struct in6_addr *v6daddr) +{ + struct inetpeer_addr daddr; + + daddr.a6 = *v6daddr; + daddr.family = AF_INET6; + return inet_getpeer(base, &daddr); +} + +static inline int inetpeer_addr_cmp(const struct inetpeer_addr *a, + const struct inetpeer_addr *b) +{ + int i, n; + + if (a->family == AF_INET) + n = sizeof(a->a4) / sizeof(u32); + else + n = sizeof(a->a6) / sizeof(u32); + + for (i = 0; i < n; i++) { + if (a->key[i] == b->key[i]) + continue; + if (a->key[i] < b->key[i]) + return -1; + return 1; + } + + return 0; +} + +/* can be called from BH context or outside */ +void inet_putpeer(struct inet_peer *p); +bool inet_peer_xrlim_allow(struct inet_peer *peer, int timeout); + +void inetpeer_invalidate_tree(struct inet_peer_base *); + +#endif /* _NET_INETPEER_H */ -- cgit v1.3.1