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/fuse/Kconfig | 78 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 78 insertions(+) create mode 100644 fs/fuse/Kconfig (limited to 'fs/fuse/Kconfig') diff --git a/fs/fuse/Kconfig b/fs/fuse/Kconfig new file mode 100644 index 000000000..3a4ae632c --- /dev/null +++ b/fs/fuse/Kconfig @@ -0,0 +1,78 @@ +# SPDX-License-Identifier: GPL-2.0-only +config FUSE_FS + tristate "FUSE (Filesystem in Userspace) support" + select FS_POSIX_ACL + select FS_IOMAP + help + With FUSE it is possible to implement a fully functional filesystem + in a userspace program. + + There's also a companion library: libfuse2. This library is available + from the FUSE homepage: + + although chances are your distribution already has that library + installed if you've installed the "fuse" package itself. + + See for more information. + See for needed library/utility version. + + If you want to develop a userspace FS, or if you want to use + a filesystem based on FUSE, answer Y or M. + +config CUSE + tristate "Character device in Userspace support" + depends on FUSE_FS + help + This FUSE extension allows character devices to be + implemented in userspace. + + If you want to develop or use a userspace character device + based on CUSE, answer Y or M. + +config VIRTIO_FS + tristate "Virtio Filesystem" + depends on FUSE_FS + select VIRTIO + help + The Virtio Filesystem allows guests to mount file systems from the + host. + + If you want to share files between guests or with the host, answer Y + or M. + +config FUSE_DAX + bool "Virtio Filesystem Direct Host Memory Access support" + default y + select INTERVAL_TREE + depends on VIRTIO_FS + depends on FS_DAX + depends on DAX + help + This allows bypassing guest page cache and allows mapping host page + cache directly in guest address space. + + If you want to allow mounting a Virtio Filesystem with the "dax" + option, answer Y. + +config FUSE_PASSTHROUGH + bool "FUSE passthrough operations support" + default y + depends on FUSE_FS + select FS_STACK + help + This allows bypassing FUSE server by mapping specific FUSE operations + to be performed directly on a backing file. + + If you want to allow passthrough operations, answer Y. + +config FUSE_IO_URING + bool "FUSE communication over io-uring" + default y + depends on FUSE_FS + depends on IO_URING + help + This allows sending FUSE requests over the io-uring interface and + also adds request core affinity. + + If you want to allow fuse server/client communication through io-uring, + answer Y -- cgit v1.3.1