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/mse.c | 328 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 328 insertions(+) create mode 100644 net/ethtool/mse.c (limited to 'net/ethtool/mse.c') diff --git a/net/ethtool/mse.c b/net/ethtool/mse.c new file mode 100644 index 000000000..e91b74430 --- /dev/null +++ b/net/ethtool/mse.c @@ -0,0 +1,328 @@ +// SPDX-License-Identifier: GPL-2.0-only + +#include +#include +#include + +#include "common.h" +#include "netlink.h" + +/* Channels A-D only; WORST and LINK are exclusive alternatives */ +#define PHY_MSE_CHANNEL_COUNT 4 + +struct mse_req_info { + struct ethnl_req_info base; +}; + +struct mse_snapshot_entry { + struct phy_mse_snapshot snapshot; + int channel; +}; + +struct mse_reply_data { + struct ethnl_reply_data base; + struct phy_mse_capability capability; + struct mse_snapshot_entry *snapshots; + unsigned int num_snapshots; +}; + +static struct mse_reply_data * +mse_repdata(const struct ethnl_reply_data *reply_base) +{ + return container_of(reply_base, struct mse_reply_data, base); +} + +const struct nla_policy ethnl_mse_get_policy[] = { + [ETHTOOL_A_MSE_HEADER] = NLA_POLICY_NESTED(ethnl_header_policy_phy), +}; + +static int get_snapshot_if_supported(struct phy_device *phydev, + struct mse_reply_data *data, + unsigned int *idx, u32 cap_bit, + enum phy_mse_channel channel) +{ + int ret; + + if (data->capability.supported_caps & cap_bit) { + ret = phydev->drv->get_mse_snapshot(phydev, channel, + &data->snapshots[*idx].snapshot); + if (ret) + return ret; + data->snapshots[*idx].channel = channel; + (*idx)++; + } + + return 0; +} + +static int mse_get_channels(struct phy_device *phydev, + struct mse_reply_data *data) +{ + unsigned int i = 0; + int ret; + + if (!data->capability.supported_caps) + return 0; + + data->snapshots = kzalloc_objs(*data->snapshots, PHY_MSE_CHANNEL_COUNT); + if (!data->snapshots) + return -ENOMEM; + + /* Priority 1: Individual channels */ + ret = get_snapshot_if_supported(phydev, data, &i, PHY_MSE_CAP_CHANNEL_A, + PHY_MSE_CHANNEL_A); + if (ret) + return ret; + ret = get_snapshot_if_supported(phydev, data, &i, PHY_MSE_CAP_CHANNEL_B, + PHY_MSE_CHANNEL_B); + if (ret) + return ret; + ret = get_snapshot_if_supported(phydev, data, &i, PHY_MSE_CAP_CHANNEL_C, + PHY_MSE_CHANNEL_C); + if (ret) + return ret; + ret = get_snapshot_if_supported(phydev, data, &i, PHY_MSE_CAP_CHANNEL_D, + PHY_MSE_CHANNEL_D); + if (ret) + return ret; + + /* If any individual channels were found, we are done. */ + if (i > 0) { + data->num_snapshots = i; + return 0; + } + + /* Priority 2: Worst channel, if no individual channels supported. */ + ret = get_snapshot_if_supported(phydev, data, &i, + PHY_MSE_CAP_WORST_CHANNEL, + PHY_MSE_CHANNEL_WORST); + if (ret) + return ret; + + /* If worst channel was found, we are done. */ + if (i > 0) { + data->num_snapshots = i; + return 0; + } + + /* Priority 3: Link-wide, if nothing else is supported. */ + ret = get_snapshot_if_supported(phydev, data, &i, PHY_MSE_CAP_LINK, + PHY_MSE_CHANNEL_LINK); + if (ret) + return ret; + + data->num_snapshots = i; + return 0; +} + +static int mse_prepare_data(const struct ethnl_req_info *req_base, + struct ethnl_reply_data *reply_base, + const struct genl_info *info) +{ + struct mse_reply_data *data = mse_repdata(reply_base); + struct net_device *dev = reply_base->dev; + struct phy_device *phydev; + int ret; + + phydev = ethnl_req_get_phydev(req_base, info->attrs, + ETHTOOL_A_MSE_HEADER, info->extack); + if (IS_ERR(phydev)) + return PTR_ERR(phydev); + if (!phydev) + return -EOPNOTSUPP; + + ret = ethnl_ops_begin(dev); + if (ret) + return ret; + + mutex_lock(&phydev->lock); + + if (!phydev->drv || !phydev->drv->get_mse_capability || + !phydev->drv->get_mse_snapshot) { + ret = -EOPNOTSUPP; + goto out_unlock; + } + if (!phydev->link) { + ret = -ENETDOWN; + goto out_unlock; + } + + ret = phydev->drv->get_mse_capability(phydev, &data->capability); + if (ret) + goto out_unlock; + + ret = mse_get_channels(phydev, data); + +out_unlock: + mutex_unlock(&phydev->lock); + ethnl_ops_complete(dev); + if (ret) + kfree(data->snapshots); + return ret; +} + +static void mse_cleanup_data(struct ethnl_reply_data *reply_base) +{ + struct mse_reply_data *data = mse_repdata(reply_base); + + kfree(data->snapshots); +} + +static int mse_reply_size(const struct ethnl_req_info *req_base, + const struct ethnl_reply_data *reply_base) +{ + const struct mse_reply_data *data = mse_repdata(reply_base); + size_t len = 0; + unsigned int i; + + /* ETHTOOL_A_MSE_CAPABILITIES */ + len += nla_total_size(0); + if (data->capability.supported_caps & PHY_MSE_CAP_AVG) + /* ETHTOOL_A_MSE_CAPABILITIES_MAX_AVERAGE_MSE */ + len += nla_total_size(sizeof(u64)); + if (data->capability.supported_caps & (PHY_MSE_CAP_PEAK | + PHY_MSE_CAP_WORST_PEAK)) + /* ETHTOOL_A_MSE_CAPABILITIES_MAX_PEAK_MSE */ + len += nla_total_size(sizeof(u64)); + /* ETHTOOL_A_MSE_CAPABILITIES_REFRESH_RATE_PS */ + len += nla_total_size(sizeof(u64)); + /* ETHTOOL_A_MSE_CAPABILITIES_NUM_SYMBOLS */ + len += nla_total_size(sizeof(u64)); + + for (i = 0; i < data->num_snapshots; i++) { + size_t snapshot_len = 0; + + /* Per-channel nest (e.g., ETHTOOL_A_MSE_CHANNEL_A / _B / _C / + * _D / _WORST_CHANNEL / _LINK) + */ + snapshot_len += nla_total_size(0); + + if (data->capability.supported_caps & PHY_MSE_CAP_AVG) + snapshot_len += nla_total_size(sizeof(u64)); + if (data->capability.supported_caps & PHY_MSE_CAP_PEAK) + snapshot_len += nla_total_size(sizeof(u64)); + if (data->capability.supported_caps & PHY_MSE_CAP_WORST_PEAK) + snapshot_len += nla_total_size(sizeof(u64)); + + len += snapshot_len; + } + + return len; +} + +static int mse_channel_to_attr(int ch) +{ + switch (ch) { + case PHY_MSE_CHANNEL_A: + return ETHTOOL_A_MSE_CHANNEL_A; + case PHY_MSE_CHANNEL_B: + return ETHTOOL_A_MSE_CHANNEL_B; + case PHY_MSE_CHANNEL_C: + return ETHTOOL_A_MSE_CHANNEL_C; + case PHY_MSE_CHANNEL_D: + return ETHTOOL_A_MSE_CHANNEL_D; + case PHY_MSE_CHANNEL_WORST: + return ETHTOOL_A_MSE_WORST_CHANNEL; + case PHY_MSE_CHANNEL_LINK: + return ETHTOOL_A_MSE_LINK; + default: + return -EINVAL; + } +} + +static int mse_fill_reply(struct sk_buff *skb, + const struct ethnl_req_info *req_base, + const struct ethnl_reply_data *reply_base) +{ + const struct mse_reply_data *data = mse_repdata(reply_base); + struct nlattr *nest; + unsigned int i; + int ret; + + nest = nla_nest_start(skb, ETHTOOL_A_MSE_CAPABILITIES); + if (!nest) + return -EMSGSIZE; + + if (data->capability.supported_caps & PHY_MSE_CAP_AVG) { + ret = nla_put_uint(skb, + ETHTOOL_A_MSE_CAPABILITIES_MAX_AVERAGE_MSE, + data->capability.max_average_mse); + if (ret < 0) + goto nla_put_nest_failure; + } + + if (data->capability.supported_caps & (PHY_MSE_CAP_PEAK | + PHY_MSE_CAP_WORST_PEAK)) { + ret = nla_put_uint(skb, ETHTOOL_A_MSE_CAPABILITIES_MAX_PEAK_MSE, + data->capability.max_peak_mse); + if (ret < 0) + goto nla_put_nest_failure; + } + + ret = nla_put_uint(skb, ETHTOOL_A_MSE_CAPABILITIES_REFRESH_RATE_PS, + data->capability.refresh_rate_ps); + if (ret < 0) + goto nla_put_nest_failure; + + ret = nla_put_uint(skb, ETHTOOL_A_MSE_CAPABILITIES_NUM_SYMBOLS, + data->capability.num_symbols); + if (ret < 0) + goto nla_put_nest_failure; + + nla_nest_end(skb, nest); + + for (i = 0; i < data->num_snapshots; i++) { + const struct mse_snapshot_entry *s = &data->snapshots[i]; + int chan_attr; + + chan_attr = mse_channel_to_attr(s->channel); + if (chan_attr < 0) + return chan_attr; + + nest = nla_nest_start(skb, chan_attr); + if (!nest) + return -EMSGSIZE; + + if (data->capability.supported_caps & PHY_MSE_CAP_AVG) { + ret = nla_put_uint(skb, + ETHTOOL_A_MSE_SNAPSHOT_AVERAGE_MSE, + s->snapshot.average_mse); + if (ret) + goto nla_put_nest_failure; + } + if (data->capability.supported_caps & PHY_MSE_CAP_PEAK) { + ret = nla_put_uint(skb, ETHTOOL_A_MSE_SNAPSHOT_PEAK_MSE, + s->snapshot.peak_mse); + if (ret) + goto nla_put_nest_failure; + } + if (data->capability.supported_caps & PHY_MSE_CAP_WORST_PEAK) { + ret = nla_put_uint(skb, + ETHTOOL_A_MSE_SNAPSHOT_WORST_PEAK_MSE, + s->snapshot.worst_peak_mse); + if (ret) + goto nla_put_nest_failure; + } + + nla_nest_end(skb, nest); + } + + return 0; + +nla_put_nest_failure: + nla_nest_cancel(skb, nest); + return ret; +} + +const struct ethnl_request_ops ethnl_mse_request_ops = { + .request_cmd = ETHTOOL_MSG_MSE_GET, + .reply_cmd = ETHTOOL_MSG_MSE_GET_REPLY, + .hdr_attr = ETHTOOL_A_MSE_HEADER, + .req_info_size = sizeof(struct mse_req_info), + .reply_data_size = sizeof(struct mse_reply_data), + + .prepare_data = mse_prepare_data, + .cleanup_data = mse_cleanup_data, + .reply_size = mse_reply_size, + .fill_reply = mse_fill_reply, +}; -- cgit v1.3.1