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/media/videobuf2-dvb.h | 69 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 69 insertions(+) create mode 100644 include/media/videobuf2-dvb.h (limited to 'include/media/videobuf2-dvb.h') diff --git a/include/media/videobuf2-dvb.h b/include/media/videobuf2-dvb.h new file mode 100644 index 000000000..2d577b945 --- /dev/null +++ b/include/media/videobuf2-dvb.h @@ -0,0 +1,69 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _VIDEOBUF2_DVB_H_ +#define _VIDEOBUF2_DVB_H_ + +#include +#include +#include +#include +#include +#include + +/* We don't actually need to include media-device.h here */ +struct media_device; + +/* + * TODO: This header file should be replaced with videobuf2-core.h + * Currently, vb2_thread is not a stuff of videobuf2-core, + * since vb2_thread has many dependencies on videobuf2-v4l2. + */ + +struct vb2_dvb { + /* filling that the job of the driver */ + char *name; + struct dvb_frontend *frontend; + struct vb2_queue dvbq; + + /* vb2-dvb state info */ + struct mutex lock; + int nfeeds; + + /* vb2_dvb_(un)register manages this */ + struct dvb_demux demux; + struct dmxdev dmxdev; + struct dmx_frontend fe_hw; + struct dmx_frontend fe_mem; + struct dvb_net net; +}; + +struct vb2_dvb_frontend { + struct list_head felist; + int id; + struct vb2_dvb dvb; +}; + +struct vb2_dvb_frontends { + struct list_head felist; + struct mutex lock; + struct dvb_adapter adapter; + int active_fe_id; /* Indicates which frontend in the felist is in use */ + int gate; /* Frontend with gate control 0=!MFE,1=fe0,2=fe1 etc */ +}; + +int vb2_dvb_register_bus(struct vb2_dvb_frontends *f, + struct module *module, + void *adapter_priv, + struct device *device, + struct media_device *mdev, + short *adapter_nr, + int mfe_shared); + +void vb2_dvb_unregister_bus(struct vb2_dvb_frontends *f); + +struct vb2_dvb_frontend *vb2_dvb_alloc_frontend(struct vb2_dvb_frontends *f, int id); +void vb2_dvb_dealloc_frontends(struct vb2_dvb_frontends *f); + +struct vb2_dvb_frontend *vb2_dvb_get_frontend(struct vb2_dvb_frontends *f, int id); +int vb2_dvb_find_frontend(struct vb2_dvb_frontends *f, struct dvb_frontend *p); + +#endif /* _VIDEOBUF2_DVB_H_ */ -- cgit v1.3.1