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/rds/sysctl.c | 109 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 109 insertions(+) create mode 100644 net/rds/sysctl.c (limited to 'net/rds/sysctl.c') diff --git a/net/rds/sysctl.c b/net/rds/sysctl.c new file mode 100644 index 000000000..025f518a4 --- /dev/null +++ b/net/rds/sysctl.c @@ -0,0 +1,109 @@ +/* + * Copyright (c) 2006 Oracle. All rights reserved. + * + * This software is available to you under a choice of one of two + * licenses. You may choose to be licensed under the terms of the GNU + * General Public License (GPL) Version 2, available from the file + * COPYING in the main directory of this source tree, or the + * OpenIB.org BSD license below: + * + * Redistribution and use in source and binary forms, with or + * without modification, are permitted provided that the following + * conditions are met: + * + * - Redistributions of source code must retain the above + * copyright notice, this list of conditions and the following + * disclaimer. + * + * - Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials + * provided with the distribution. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + */ +#include +#include +#include + +#include "rds.h" + +static struct ctl_table_header *rds_sysctl_reg_table; + +static unsigned long rds_sysctl_reconnect_min = 1; +static unsigned long rds_sysctl_reconnect_max = ~0UL; + +unsigned long rds_sysctl_reconnect_min_jiffies; +unsigned long rds_sysctl_reconnect_max_jiffies = HZ; + +unsigned int rds_sysctl_max_unacked_packets = 8; +unsigned int rds_sysctl_max_unacked_bytes = (16 << 20); + +unsigned int rds_sysctl_ping_enable = 1; + +static struct ctl_table rds_sysctl_rds_table[] = { + { + .procname = "reconnect_min_delay_ms", + .data = &rds_sysctl_reconnect_min_jiffies, + .maxlen = sizeof(unsigned long), + .mode = 0644, + .proc_handler = proc_doulongvec_ms_jiffies_minmax, + .extra1 = &rds_sysctl_reconnect_min, + .extra2 = &rds_sysctl_reconnect_max_jiffies, + }, + { + .procname = "reconnect_max_delay_ms", + .data = &rds_sysctl_reconnect_max_jiffies, + .maxlen = sizeof(unsigned long), + .mode = 0644, + .proc_handler = proc_doulongvec_ms_jiffies_minmax, + .extra1 = &rds_sysctl_reconnect_min_jiffies, + .extra2 = &rds_sysctl_reconnect_max, + }, + { + .procname = "max_unacked_packets", + .data = &rds_sysctl_max_unacked_packets, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec, + }, + { + .procname = "max_unacked_bytes", + .data = &rds_sysctl_max_unacked_bytes, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec, + }, + { + .procname = "ping_enable", + .data = &rds_sysctl_ping_enable, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec, + }, +}; + +void rds_sysctl_exit(void) +{ + unregister_net_sysctl_table(rds_sysctl_reg_table); +} + +int rds_sysctl_init(void) +{ + rds_sysctl_reconnect_min = msecs_to_jiffies(1); + rds_sysctl_reconnect_min_jiffies = rds_sysctl_reconnect_min; + + rds_sysctl_reg_table = + register_net_sysctl(&init_net, "net/rds", rds_sysctl_rds_table); + if (!rds_sysctl_reg_table) + return -ENOMEM; + return 0; +} -- cgit v1.3.1