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 --- drivers/interconnect/bulk.c | 159 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 159 insertions(+) create mode 100644 drivers/interconnect/bulk.c (limited to 'drivers/interconnect/bulk.c') diff --git a/drivers/interconnect/bulk.c b/drivers/interconnect/bulk.c new file mode 100644 index 000000000..8b1d8a412 --- /dev/null +++ b/drivers/interconnect/bulk.c @@ -0,0 +1,159 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include +#include +#include + +/** + * of_icc_bulk_get() - get interconnect paths + * @dev: the device requesting the path + * @num_paths: the number of icc_bulk_data + * @paths: the table with the paths we want to get + * + * Returns 0 on success or negative errno otherwise. + */ +int __must_check of_icc_bulk_get(struct device *dev, int num_paths, + struct icc_bulk_data *paths) +{ + int ret, i; + + for (i = 0; i < num_paths; i++) { + paths[i].path = of_icc_get(dev, paths[i].name); + if (IS_ERR(paths[i].path)) { + ret = PTR_ERR(paths[i].path); + if (ret != -EPROBE_DEFER) + dev_err(dev, "of_icc_get() failed on path %s (%d)\n", + paths[i].name, ret); + paths[i].path = NULL; + goto err; + } + } + + return 0; + +err: + icc_bulk_put(i, paths); + + return ret; +} +EXPORT_SYMBOL_GPL(of_icc_bulk_get); + +/** + * icc_bulk_put() - put a list of interconnect paths + * @num_paths: the number of icc_bulk_data + * @paths: the icc_bulk_data table with the paths being put + */ +void icc_bulk_put(int num_paths, struct icc_bulk_data *paths) +{ + while (--num_paths >= 0) { + icc_put(paths[num_paths].path); + paths[num_paths].path = NULL; + } +} +EXPORT_SYMBOL_GPL(icc_bulk_put); + +/** + * icc_bulk_set_bw() - set bandwidth to a set of paths + * @num_paths: the number of icc_bulk_data + * @paths: the icc_bulk_data table containing the paths and bandwidth + * + * Returns 0 on success or negative errno otherwise. + */ +int icc_bulk_set_bw(int num_paths, const struct icc_bulk_data *paths) +{ + int ret = 0; + int i; + + for (i = 0; i < num_paths; i++) { + ret = icc_set_bw(paths[i].path, paths[i].avg_bw, paths[i].peak_bw); + if (ret) { + pr_err("icc_set_bw() failed on path %s (%d)\n", paths[i].name, ret); + return ret; + } + } + + return ret; +} +EXPORT_SYMBOL_GPL(icc_bulk_set_bw); + +/** + * icc_bulk_enable() - enable a previously disabled set of paths + * @num_paths: the number of icc_bulk_data + * @paths: the icc_bulk_data table containing the paths and bandwidth + * + * Returns 0 on success or negative errno otherwise. + */ +int icc_bulk_enable(int num_paths, const struct icc_bulk_data *paths) +{ + int ret, i; + + for (i = 0; i < num_paths; i++) { + ret = icc_enable(paths[i].path); + if (ret) { + pr_err("icc_enable() failed on path %s (%d)\n", paths[i].name, ret); + goto err; + } + } + + return 0; + +err: + icc_bulk_disable(i, paths); + + return ret; +} +EXPORT_SYMBOL_GPL(icc_bulk_enable); + +/** + * icc_bulk_disable() - disable a set of interconnect paths + * @num_paths: the number of icc_bulk_data + * @paths: the icc_bulk_data table containing the paths and bandwidth + */ +void icc_bulk_disable(int num_paths, const struct icc_bulk_data *paths) +{ + while (--num_paths >= 0) + icc_disable(paths[num_paths].path); +} +EXPORT_SYMBOL_GPL(icc_bulk_disable); + +struct icc_bulk_devres { + struct icc_bulk_data *paths; + int num_paths; +}; + +static void devm_icc_bulk_release(struct device *dev, void *res) +{ + struct icc_bulk_devres *devres = res; + + icc_bulk_put(devres->num_paths, devres->paths); +} + +/** + * devm_of_icc_bulk_get() - resource managed of_icc_bulk_get + * @dev: the device requesting the path + * @num_paths: the number of icc_bulk_data + * @paths: the table with the paths we want to get + * + * Returns 0 on success or negative errno otherwise. + */ +int devm_of_icc_bulk_get(struct device *dev, int num_paths, struct icc_bulk_data *paths) +{ + struct icc_bulk_devres *devres; + int ret; + + devres = devres_alloc(devm_icc_bulk_release, sizeof(*devres), GFP_KERNEL); + if (!devres) + return -ENOMEM; + + ret = of_icc_bulk_get(dev, num_paths, paths); + if (!ret) { + devres->paths = paths; + devres->num_paths = num_paths; + devres_add(dev, devres); + } else { + devres_free(devres); + } + + return ret; +} +EXPORT_SYMBOL_GPL(devm_of_icc_bulk_get); -- cgit v1.3.1