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 --- net/ethtool/linkinfo.c | 145 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 145 insertions(+) create mode 100644 net/ethtool/linkinfo.c (limited to 'net/ethtool/linkinfo.c') diff --git a/net/ethtool/linkinfo.c b/net/ethtool/linkinfo.c new file mode 100644 index 000000000..d5b3dbc53 --- /dev/null +++ b/net/ethtool/linkinfo.c @@ -0,0 +1,145 @@ +// SPDX-License-Identifier: GPL-2.0-only + +#include "common.h" +#include "netlink.h" + +struct linkinfo_req_info { + struct ethnl_req_info base; +}; + +struct linkinfo_reply_data { + struct ethnl_reply_data base; + struct ethtool_link_ksettings ksettings; + struct ethtool_link_settings *lsettings; +}; + +#define LINKINFO_REPDATA(__reply_base) \ + container_of(__reply_base, struct linkinfo_reply_data, base) + +const struct nla_policy ethnl_linkinfo_get_policy[] = { + [ETHTOOL_A_LINKINFO_HEADER] = + NLA_POLICY_NESTED(ethnl_header_policy), +}; + +static int linkinfo_prepare_data(const struct ethnl_req_info *req_base, + struct ethnl_reply_data *reply_base, + const struct genl_info *info) +{ + struct linkinfo_reply_data *data = LINKINFO_REPDATA(reply_base); + struct net_device *dev = reply_base->dev; + int ret; + + data->lsettings = &data->ksettings.base; + + ret = ethnl_ops_begin(dev); + if (ret < 0) + return ret; + ret = netif_get_link_ksettings(dev, &data->ksettings); + if (ret < 0) + GENL_SET_ERR_MSG(info, "failed to retrieve link settings"); + ethnl_ops_complete(dev); + + return ret; +} + +static int linkinfo_reply_size(const struct ethnl_req_info *req_base, + const struct ethnl_reply_data *reply_base) +{ + return nla_total_size(sizeof(u8)) /* LINKINFO_PORT */ + + nla_total_size(sizeof(u8)) /* LINKINFO_PHYADDR */ + + nla_total_size(sizeof(u8)) /* LINKINFO_TP_MDIX */ + + nla_total_size(sizeof(u8)) /* LINKINFO_TP_MDIX_CTRL */ + + nla_total_size(sizeof(u8)) /* LINKINFO_TRANSCEIVER */ + + 0; +} + +static int linkinfo_fill_reply(struct sk_buff *skb, + const struct ethnl_req_info *req_base, + const struct ethnl_reply_data *reply_base) +{ + const struct linkinfo_reply_data *data = LINKINFO_REPDATA(reply_base); + + if (nla_put_u8(skb, ETHTOOL_A_LINKINFO_PORT, data->lsettings->port) || + nla_put_u8(skb, ETHTOOL_A_LINKINFO_PHYADDR, + data->lsettings->phy_address) || + nla_put_u8(skb, ETHTOOL_A_LINKINFO_TP_MDIX, + data->lsettings->eth_tp_mdix) || + nla_put_u8(skb, ETHTOOL_A_LINKINFO_TP_MDIX_CTRL, + data->lsettings->eth_tp_mdix_ctrl) || + nla_put_u8(skb, ETHTOOL_A_LINKINFO_TRANSCEIVER, + data->lsettings->transceiver)) + return -EMSGSIZE; + + return 0; +} + +/* LINKINFO_SET */ + +const struct nla_policy ethnl_linkinfo_set_policy[] = { + [ETHTOOL_A_LINKINFO_HEADER] = + NLA_POLICY_NESTED(ethnl_header_policy), + [ETHTOOL_A_LINKINFO_PORT] = { .type = NLA_U8 }, + [ETHTOOL_A_LINKINFO_PHYADDR] = { .type = NLA_U8 }, + [ETHTOOL_A_LINKINFO_TP_MDIX_CTRL] = { .type = NLA_U8 }, +}; + +static int +ethnl_set_linkinfo_validate(struct ethnl_req_info *req_info, + struct genl_info *info) +{ + const struct ethtool_ops *ops = req_info->dev->ethtool_ops; + + if (!ops->get_link_ksettings || !ops->set_link_ksettings) + return -EOPNOTSUPP; + return 1; +} + +static int +ethnl_set_linkinfo(struct ethnl_req_info *req_info, struct genl_info *info) +{ + struct ethtool_link_ksettings ksettings = {}; + struct ethtool_link_settings *lsettings; + struct net_device *dev = req_info->dev; + struct nlattr **tb = info->attrs; + bool mod = false; + int ret; + + ret = netif_get_link_ksettings(dev, &ksettings); + if (ret < 0) { + GENL_SET_ERR_MSG(info, "failed to retrieve link settings"); + return ret; + } + lsettings = &ksettings.base; + + ethnl_update_u8(&lsettings->port, tb[ETHTOOL_A_LINKINFO_PORT], &mod); + ethnl_update_u8(&lsettings->phy_address, tb[ETHTOOL_A_LINKINFO_PHYADDR], + &mod); + ethnl_update_u8(&lsettings->eth_tp_mdix_ctrl, + tb[ETHTOOL_A_LINKINFO_TP_MDIX_CTRL], &mod); + if (!mod) + return 0; + + ret = dev->ethtool_ops->set_link_ksettings(dev, &ksettings); + if (ret < 0) { + GENL_SET_ERR_MSG(info, "link settings update failed"); + return ret; + } + + return 1; +} + +const struct ethnl_request_ops ethnl_linkinfo_request_ops = { + .request_cmd = ETHTOOL_MSG_LINKINFO_GET, + .reply_cmd = ETHTOOL_MSG_LINKINFO_GET_REPLY, + .hdr_attr = ETHTOOL_A_LINKINFO_HEADER, + .req_info_size = sizeof(struct linkinfo_req_info), + .reply_data_size = sizeof(struct linkinfo_reply_data), + + .prepare_data = linkinfo_prepare_data, + .reply_size = linkinfo_reply_size, + .fill_reply = linkinfo_fill_reply, + + .set_validate = ethnl_set_linkinfo_validate, + .set = ethnl_set_linkinfo, + .set_ntf_cmd = ETHTOOL_MSG_LINKINFO_NTF, +}; -- cgit v1.3.1