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 --- fs/xfs/xfs_rtalloc.h | 80 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 80 insertions(+) create mode 100644 fs/xfs/xfs_rtalloc.h (limited to 'fs/xfs/xfs_rtalloc.h') diff --git a/fs/xfs/xfs_rtalloc.h b/fs/xfs/xfs_rtalloc.h new file mode 100644 index 000000000..78a690b48 --- /dev/null +++ b/fs/xfs/xfs_rtalloc.h @@ -0,0 +1,80 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2000-2003,2005 Silicon Graphics, Inc. + * All Rights Reserved. + */ +#ifndef __XFS_RTALLOC_H__ +#define __XFS_RTALLOC_H__ + +/* kernel only definitions and functions */ + +struct xfs_mount; +struct xfs_trans; + +#ifdef CONFIG_XFS_RT +/* rtgroup superblock initialization */ +int xfs_rtmount_readsb(struct xfs_mount *mp); +void xfs_rtmount_freesb(struct xfs_mount *mp); + +/* + * Initialize realtime fields in the mount structure. + */ +int /* error */ +xfs_rtmount_init( + struct xfs_mount *mp); /* file system mount structure */ +void +xfs_rtunmount_inodes( + struct xfs_mount *mp); + +/* + * Get the bitmap and summary inodes into the mount structure + * at mount time. + */ +int /* error */ +xfs_rtmount_inodes( + struct xfs_mount *mp); /* file system mount structure */ + +/* + * Grow the realtime area of the filesystem. + */ +int +xfs_growfs_rt( + struct xfs_mount *mp, /* file system mount structure */ + xfs_growfs_rt_t *in); /* user supplied growfs struct */ + +int xfs_rtalloc_reinit_frextents(struct xfs_mount *mp); +int xfs_growfs_check_rtgeom(const struct xfs_mount *mp, xfs_rfsblock_t dblocks, + xfs_rfsblock_t rblocks, xfs_agblock_t rextsize); +#else +# define xfs_growfs_rt(mp,in) (-ENOSYS) +# define xfs_rtalloc_reinit_frextents(m) (0) +# define xfs_rtmount_readsb(mp) (0) +# define xfs_rtmount_freesb(mp) ((void)0) +static inline int /* error */ +xfs_rtmount_init( + xfs_mount_t *mp) /* file system mount structure */ +{ + if (mp->m_sb.sb_rblocks == 0) + return 0; + + xfs_warn(mp, "Not built with CONFIG_XFS_RT"); + return -ENOSYS; +} +# define xfs_rtmount_inodes(m) (((mp)->m_sb.sb_rblocks == 0)? 0 : (-ENOSYS)) +# define xfs_rtunmount_inodes(m) + +static inline int +xfs_growfs_check_rtgeom(const struct xfs_mount *mp, + xfs_rfsblock_t dblocks, xfs_rfsblock_t rblocks, + xfs_extlen_t rextsize) +{ + return 0; +} +#endif /* CONFIG_XFS_RT */ + +int xfs_rtallocate_rtgs(struct xfs_trans *tp, xfs_fsblock_t bno_hint, + xfs_rtxlen_t minlen, xfs_rtxlen_t maxlen, xfs_rtxlen_t prod, + bool wasdel, bool initial_user_data, xfs_rtblock_t *bno, + xfs_extlen_t *blen); + +#endif /* __XFS_RTALLOC_H__ */ -- cgit v1.3.1