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/ext2/ioctl.c | 159 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 159 insertions(+) create mode 100644 fs/ext2/ioctl.c (limited to 'fs/ext2/ioctl.c') diff --git a/fs/ext2/ioctl.c b/fs/ext2/ioctl.c new file mode 100644 index 000000000..c3fea55b8 --- /dev/null +++ b/fs/ext2/ioctl.c @@ -0,0 +1,159 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * linux/fs/ext2/ioctl.c + * + * Copyright (C) 1993, 1994, 1995 + * Remy Card (card@masi.ibp.fr) + * Laboratoire MASI - Institut Blaise Pascal + * Universite Pierre et Marie Curie (Paris VI) + */ + +#include "ext2.h" +#include +#include +#include +#include +#include +#include +#include +#include + +int ext2_fileattr_get(struct dentry *dentry, struct file_kattr *fa) +{ + struct ext2_inode_info *ei = EXT2_I(d_inode(dentry)); + + fileattr_fill_flags(fa, ei->i_flags & EXT2_FL_USER_VISIBLE); + + return 0; +} + +int ext2_fileattr_set(struct mnt_idmap *idmap, + struct dentry *dentry, struct file_kattr *fa) +{ + struct inode *inode = d_inode(dentry); + struct ext2_inode_info *ei = EXT2_I(inode); + + if (fileattr_has_fsx(fa)) + return -EOPNOTSUPP; + + /* Is it quota file? Do not allow user to mess with it */ + if (IS_NOQUOTA(inode)) + return -EPERM; + + ei->i_flags = (ei->i_flags & ~EXT2_FL_USER_MODIFIABLE) | + (fa->flags & EXT2_FL_USER_MODIFIABLE); + + ext2_set_inode_flags(inode); + inode_set_ctime_current(inode); + mark_inode_dirty(inode); + + return 0; +} + + +long ext2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) +{ + struct inode *inode = file_inode(filp); + struct ext2_inode_info *ei = EXT2_I(inode); + unsigned short rsv_window_size; + int ret; + + ext2_debug ("cmd = %u, arg = %lu\n", cmd, arg); + + switch (cmd) { + case EXT2_IOC_GETVERSION: + return put_user(inode->i_generation, (int __user *) arg); + case EXT2_IOC_SETVERSION: { + __u32 generation; + + if (!inode_owner_or_capable(&nop_mnt_idmap, inode)) + return -EPERM; + ret = mnt_want_write_file(filp); + if (ret) + return ret; + if (get_user(generation, (int __user *) arg)) { + ret = -EFAULT; + goto setversion_out; + } + + inode_lock(inode); + inode_set_ctime_current(inode); + inode->i_generation = generation; + inode_unlock(inode); + + mark_inode_dirty(inode); +setversion_out: + mnt_drop_write_file(filp); + return ret; + } + case EXT2_IOC_GETRSVSZ: + if (test_opt(inode->i_sb, RESERVATION) + && S_ISREG(inode->i_mode) + && ei->i_block_alloc_info) { + rsv_window_size = ei->i_block_alloc_info->rsv_window_node.rsv_goal_size; + return put_user(rsv_window_size, (int __user *)arg); + } + return -ENOTTY; + case EXT2_IOC_SETRSVSZ: { + + if (!test_opt(inode->i_sb, RESERVATION) ||!S_ISREG(inode->i_mode)) + return -ENOTTY; + + if (!inode_owner_or_capable(&nop_mnt_idmap, inode)) + return -EACCES; + + if (get_user(rsv_window_size, (int __user *)arg)) + return -EFAULT; + + ret = mnt_want_write_file(filp); + if (ret) + return ret; + + if (rsv_window_size > EXT2_MAX_RESERVE_BLOCKS) + rsv_window_size = EXT2_MAX_RESERVE_BLOCKS; + + /* + * need to allocate reservation structure for this inode + * before set the window size + */ + /* + * XXX What lock should protect the rsv_goal_size? + * Accessed in ext2_get_block only. ext3 uses i_truncate. + */ + mutex_lock(&ei->truncate_mutex); + if (!ei->i_block_alloc_info) + ext2_init_block_alloc_info(inode); + + if (ei->i_block_alloc_info){ + struct ext2_reserve_window_node *rsv = &ei->i_block_alloc_info->rsv_window_node; + rsv->rsv_goal_size = rsv_window_size; + } else { + ret = -ENOMEM; + } + + mutex_unlock(&ei->truncate_mutex); + mnt_drop_write_file(filp); + return ret; + } + default: + return -ENOTTY; + } +} + +#ifdef CONFIG_COMPAT +long ext2_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) +{ + /* These are just misnamed, they actually get/put from/to user an int */ + switch (cmd) { + case EXT2_IOC32_GETVERSION: + cmd = EXT2_IOC_GETVERSION; + break; + case EXT2_IOC32_SETVERSION: + cmd = EXT2_IOC_SETVERSION; + break; + default: + return -ENOIOCTLCMD; + } + return ext2_ioctl(file, cmd, (unsigned long) compat_ptr(arg)); +} +#endif -- cgit v1.3.1