From: kernel test robot <lkp@intel.com>
To: Menglong Dong <menglong8.dong@gmail.com>,
ast@kernel.org, rostedt@goodmis.org
Cc: oe-kbuild-all@lists.linux.dev, daniel@iogearbox.net,
john.fastabend@gmail.com, andrii@kernel.org,
martin.lau@linux.dev, eddyz87@gmail.com, song@kernel.org,
yonghong.song@linux.dev, kpsingh@kernel.org, sdf@fomichev.me,
haoluo@google.com, jolsa@kernel.org, mhiramat@kernel.org,
mark.rutland@arm.com, mathieu.desnoyers@efficios.com,
jiang.biao@linux.dev, bpf@vger.kernel.org,
linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org
Subject: Re: [PATCH bpf-next v2 5/6] bpf: specify the old and new poke_type for bpf_arch_text_poke
Date: Tue, 18 Nov 2025 04:55:06 +0800 [thread overview]
Message-ID: <202511180431.JVOEm6SO-lkp@intel.com> (raw)
In-Reply-To: <20251117034906.32036-6-dongml2@chinatelecom.cn>
Hi Menglong,
kernel test robot noticed the following build errors:
[auto build test ERROR on bpf-next/master]
url: https://github.com/intel-lab-lkp/linux/commits/Menglong-Dong/ftrace-introduce-FTRACE_OPS_FL_JMP/20251117-115243
base: https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master
patch link: https://lore.kernel.org/r/20251117034906.32036-6-dongml2%40chinatelecom.cn
patch subject: [PATCH bpf-next v2 5/6] bpf: specify the old and new poke_type for bpf_arch_text_poke
config: powerpc64-randconfig-002-20251118 (https://download.01.org/0day-ci/archive/20251118/202511180431.JVOEm6SO-lkp@intel.com/config)
compiler: powerpc64-linux-gcc (GCC) 8.5.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20251118/202511180431.JVOEm6SO-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202511180431.JVOEm6SO-lkp@intel.com/
All errors (new ones prefixed by >>):
arch/powerpc/net/bpf_jit_comp.c: In function 'bpf_arch_text_poke':
>> arch/powerpc/net/bpf_jit_comp.c:1135:7: error: 'poke_type' undeclared (first use in this function); did you mean 'probe_type'?
if (poke_type != BPF_MOD_JUMP) {
^~~~~~~~~
probe_type
arch/powerpc/net/bpf_jit_comp.c:1135:7: note: each undeclared identifier is reported only once for each function it appears in
vim +1135 arch/powerpc/net/bpf_jit_comp.c
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1070
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1071 /*
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1072 * A 3-step process for bpf prog entry:
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1073 * 1. At bpf prog entry, a single nop/b:
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1074 * bpf_func:
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1075 * [nop|b] ool_stub
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1076 * 2. Out-of-line stub:
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1077 * ool_stub:
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1078 * mflr r0
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1079 * [b|bl] <bpf_prog>/<long_branch_stub>
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1080 * mtlr r0 // CONFIG_PPC_FTRACE_OUT_OF_LINE only
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1081 * b bpf_func + 4
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1082 * 3. Long branch stub:
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1083 * long_branch_stub:
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1084 * .long <branch_addr>/<dummy_tramp>
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1085 * mflr r11
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1086 * bcl 20,31,$+4
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1087 * mflr r12
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1088 * ld r12, -16(r12)
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1089 * mtctr r12
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1090 * mtlr r11 // needed to retain ftrace ABI
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1091 * bctr
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1092 *
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1093 * dummy_tramp is used to reduce synchronization requirements.
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1094 *
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1095 * When attaching a bpf trampoline to a bpf prog, we do not need any
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1096 * synchronization here since we always have a valid branch target regardless
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1097 * of the order in which the above stores are seen. dummy_tramp ensures that
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1098 * the long_branch stub goes to a valid destination on other cpus, even when
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1099 * the branch to the long_branch stub is seen before the updated trampoline
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1100 * address.
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1101 *
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1102 * However, when detaching a bpf trampoline from a bpf prog, or if changing
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1103 * the bpf trampoline address, we need synchronization to ensure that other
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1104 * cpus can no longer branch into the older trampoline so that it can be
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1105 * safely freed. bpf_tramp_image_put() uses rcu_tasks to ensure all cpus
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1106 * make forward progress, but we still need to ensure that other cpus
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1107 * execute isync (or some CSI) so that they don't go back into the
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1108 * trampoline again.
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1109 */
7cc5910294285d Menglong Dong 2025-11-17 1110 int bpf_arch_text_poke(void *ip, enum bpf_text_poke_type old_t,
7cc5910294285d Menglong Dong 2025-11-17 1111 enum bpf_text_poke_type new_t, void *old_addr,
7cc5910294285d Menglong Dong 2025-11-17 1112 void *new_addr)
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1113 {
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1114 unsigned long bpf_func, bpf_func_end, size, offset;
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1115 ppc_inst_t old_inst, new_inst;
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1116 int ret = 0, branch_flags;
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1117 char name[KSYM_NAME_LEN];
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1118
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1119 if (IS_ENABLED(CONFIG_PPC32))
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1120 return -EOPNOTSUPP;
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1121
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1122 bpf_func = (unsigned long)ip;
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1123
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1124 /* We currently only support poking bpf programs */
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1125 if (!__bpf_address_lookup(bpf_func, &size, &offset, name)) {
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1126 pr_err("%s (0x%lx): kernel/modules are not supported\n", __func__, bpf_func);
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1127 return -EOPNOTSUPP;
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1128 }
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1129
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1130 /*
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1131 * If we are not poking at bpf prog entry, then we are simply patching in/out
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1132 * an unconditional branch instruction at im->ip_after_call
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1133 */
d243b62b7bd3d5 Naveen N Rao 2024-10-30 1134 if (offset) {
d243b62b7bd3d5 Naveen N Rao 2024-10-30 @1135 if (poke_type != BPF_MOD_JUMP) {
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
next prev parent reply other threads:[~2025-11-17 20:55 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-11-17 3:49 [PATCH bpf-next v2 0/6] bpf trampoline support "jmp" mode Menglong Dong
2025-11-17 3:49 ` [PATCH bpf-next v2 1/6] ftrace: introduce FTRACE_OPS_FL_JMP Menglong Dong
2025-11-18 5:19 ` Masami Hiramatsu
2025-11-18 6:14 ` Menglong Dong
2025-11-17 3:49 ` [PATCH bpf-next v2 2/6] x86/ftrace: implement DYNAMIC_FTRACE_WITH_JMP Menglong Dong
2025-11-17 3:49 ` [PATCH bpf-next v2 3/6] bpf: fix the usage of BPF_TRAMP_F_SKIP_FRAME Menglong Dong
2025-11-17 3:49 ` [PATCH bpf-next v2 4/6] bpf,x86: adjust the "jmp" mode for bpf trampoline Menglong Dong
2025-11-17 3:49 ` [PATCH bpf-next v2 5/6] bpf: specify the old and new poke_type for bpf_arch_text_poke Menglong Dong
2025-11-17 20:55 ` kernel test robot [this message]
2025-11-17 3:49 ` [PATCH bpf-next v2 6/6] bpf: implement "jmp" mode for trampoline Menglong Dong
2025-11-17 22:49 ` kernel test robot
2025-11-18 1:20 ` Menglong Dong
2025-11-18 5:09 ` kernel test robot
2025-11-18 6:31 ` [PATCH bpf-next v2 0/6] bpf trampoline support "jmp" mode Alexei Starovoitov
2025-11-18 6:34 ` Menglong Dong
2025-11-18 6:41 ` Alexei Starovoitov
2025-11-18 6:46 ` Menglong Dong
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=202511180431.JVOEm6SO-lkp@intel.com \
--to=lkp@intel.com \
--cc=andrii@kernel.org \
--cc=ast@kernel.org \
--cc=bpf@vger.kernel.org \
--cc=daniel@iogearbox.net \
--cc=eddyz87@gmail.com \
--cc=haoluo@google.com \
--cc=jiang.biao@linux.dev \
--cc=john.fastabend@gmail.com \
--cc=jolsa@kernel.org \
--cc=kpsingh@kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-trace-kernel@vger.kernel.org \
--cc=mark.rutland@arm.com \
--cc=martin.lau@linux.dev \
--cc=mathieu.desnoyers@efficios.com \
--cc=menglong8.dong@gmail.com \
--cc=mhiramat@kernel.org \
--cc=oe-kbuild-all@lists.linux.dev \
--cc=rostedt@goodmis.org \
--cc=sdf@fomichev.me \
--cc=song@kernel.org \
--cc=yonghong.song@linux.dev \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox