Hello, kernel test robot noticed "segfault_at_ip_sp_error" on: commit: 981dfb28e2d5851435754da557baadfdcbc828a8 ("[PATCH] proc_sysctl: Fix up ->is_seen() handling") url: https://github.com/intel-lab-lkp/linux/commits/NeilBrown/proc_sysctl-Fix-up-is_seen-handling/20250613-083900 base: https://git.kernel.org/cgit/linux/kernel/git/sysctl/sysctl.git sysctl-next patch link: https://lore.kernel.org/all/174977507817.608730.3467596162021780258@xxxxxxxxxxxxxxxxxxxxx/ patch subject: [PATCH] proc_sysctl: Fix up ->is_seen() handling in testcase: ltp version: ltp-x86_64-99ebf35b3-1_20250607 with following parameters: test: net.tirpc_tests config: x86_64-rhel-9.4-ltp compiler: gcc-12 test machine: 8 threads 1 sockets Intel(R) Core(TM) i7-3770K CPU @ 3.50GHz (Ivy Bridge) with 16G memory (please refer to attached dmesg/kmsg for entire log/backtrace) 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 <oliver.sang@xxxxxxxxx> | Closes: https://lore.kernel.org/oe-lkp/202506161619.6738c86c-lkp@xxxxxxxxx kern :info : [ 157.002007] tirpc_clnt_cont[10507]: segfault at 8 ip 000055c92e030119 sp 00007ffd50302fb0 error 4 in tirpc_clnt_control[1119,55c92e030000+1000] likely on CPU 2 (core 2, socket 0) kern :info : [ 157.002435] Code: 1d 0f 00 00 31 db 48 89 c1 4c 8d 44 24 10 ba 01 00 00 00 0f 29 44 24 10 e8 44 ff ff ff 48 8d 54 24 0c be 06 00 00 00 48 89 c7 <48> 8b 40 08 ff 50 28 48 8d 35 e3 0e 00 00 bf 01 00 00 00 83 f8 01 All code ======== 0: 1d 0f 00 00 31 sbb $0x3100000f,%eax 5: db 48 89 fisttpl -0x77(%rax) 8: c1 4c 8d 44 24 rorl $0x24,0x44(%rbp,%rcx,4) d: 10 ba 01 00 00 00 adc %bh,0x1(%rdx) 13: 0f 29 44 24 10 movaps %xmm0,0x10(%rsp) 18: e8 44 ff ff ff call 0xffffffffffffff61 1d: 48 8d 54 24 0c lea 0xc(%rsp),%rdx 22: be 06 00 00 00 mov $0x6,%esi 27: 48 89 c7 mov %rax,%rdi 2a:* 48 8b 40 08 mov 0x8(%rax),%rax <-- trapping instruction 2e: ff 50 28 call *0x28(%rax) 31: 48 8d 35 e3 0e 00 00 lea 0xee3(%rip),%rsi # 0xf1b 38: bf 01 00 00 00 mov $0x1,%edi 3d: 83 f8 01 cmp $0x1,%eax Code starting with the faulting instruction =========================================== 0: 48 8b 40 08 mov 0x8(%rax),%rax 4: ff 50 28 call *0x28(%rax) 7: 48 8d 35 e3 0e 00 00 lea 0xee3(%rip),%rsi # 0xef1 e: bf 01 00 00 00 mov $0x1,%edi 13: 83 f8 01 cmp $0x1,%eax user :warn : [ 157.168019] LTP: starting tirpc_rpc_reg (rpc_test.sh -c tirpc_rpc_reg) user :warn : [ 158.080633] LTP: starting tirpc_rpc_call (rpc_test.sh -s tirpc_svc_1 -c tirpc_rpc_call) user :warn : [ 159.209909] LTP: starting tirpc_rpc_broadcast (rpc_test.sh -s tirpc_svc_1 -c tirpc_rpc_broadcast) user :warn : [ 160.241552] LTP: starting tirpc_rpc_broadcast_exp (rpc_test.sh -s tirpc_svc_1 -c tirpc_rpc_broadcast_exp -e "1,2") user :warn : [ 161.182028] LTP: starting tirpc_clnt_create (rpc_test.sh -s tirpc_svc_2 -c tirpc_clnt_create) user :warn : [ 162.081857] LTP: starting tirpc_clnt_create_timed (rpc_test.sh -s tirpc_svc_2 -c tirpc_clnt_create_timed) user :warn : [ 163.234462] LTP: starting tirpc_svc_create (rpc_test.sh -c tirpc_svc_create) user :notice: [ 163.507518] Gnu C gcc (Debian 12.2.0-14+deb12u1) 12.2.0 user :notice: [ 163.508419] Clang user :notice: [ 163.509434] Gnu make 4.3 user :notice: [ 163.510405] util-linux 2.38.1 user :warn : [ 164.010443] LTP: starting tirpc_toplevel_clnt_call (rpc_test.sh -s tirpc_svc_2 -c tirpc_toplevel_clnt_call) user :warn : [ 165.054172] LTP: starting tirpc_clnt_destroy (rpc_test.sh -s tirpc_svc_2 -c tirpc_clnt_destroy) user :warn : [ 166.170592] LTP: starting tirpc_svc_destroy (rpc_test.sh -c tirpc_svc_destroy) user :err : [ 166.988060] ------------------------------------------- The kernel config and materials to reproduce are available at: https://download.01.org/0day-ci/archive/20250616/202506161619.6738c86c-lkp@xxxxxxxxx -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki