From: kernel test robot <oliver.sang@intel.com>
To: "Jim Cromie" <jim.cromie@gmail.com>,
"Łukasz Bartosik" <ukaszb@chromium.org>
Cc: <oe-lkp@lists.linux.dev>, <lkp@intel.com>, <oliver.sang@intel.com>
Subject: [jimc:dd-shrink] [dyndbg] 30ab125417: WARNING:suspicious_RCU_usage
Date: Wed, 21 Jan 2026 14:05:12 +0800 [thread overview]
Message-ID: <202601211325.c04e2734-lkp@intel.com> (raw)
Hello,
kernel test robot noticed "WARNING:suspicious_RCU_usage" on:
commit: 30ab12541721b33af33df48048db12f23a42946d ("dyndbg: walk dd_mod_map intervals in dynamic_debug_init()")
https://github.com/jimc/linux.git dd-shrink
in testcase: boot
config: x86_64-randconfig-016-20260120
compiler: gcc-14
test machine: qemu-system-x86_64 -enable-kvm -cpu SandyBridge -smp 2 -m 32G
(please refer to attached dmesg/kmsg for entire log/backtrace)
+-----------------------------------------------------------+------------+------------+
| | f278c5d152 | 30ab125417 |
+-----------------------------------------------------------+------------+------------+
| WARNING:suspicious_RCU_usage | 0 | 18 |
+-----------------------------------------------------------+------------+------------+
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@intel.com>
| Closes: https://lore.kernel.org/oe-lkp/202601211325.c04e2734-lkp@intel.com
[ 32.321882][ T1] WARNING: suspicious RCU usage
[ 32.331885][ T1] 6.19.0-rc6-00038-g30ab12541721 #1 Not tainted
[ 32.346942][ T1] -----------------------------
[ 32.356295][ T1] lib/maple_tree.c:780 suspicious rcu_dereference_check() usage!
[ 32.368276][ T1]
[ 32.368276][ T1] other info that might help us debug this:
[ 32.368276][ T1]
[ 32.380345][ T1]
[ 32.380345][ T1] rcu_scheduler_active = 1, debug_locks = 1
[ 32.388591][ T1] no locks held by swapper/0/1.
[ 32.396226][ T1]
[ 32.396226][ T1] stack backtrace:
[ 32.407490][ T1] CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.19.0-rc6-00038-g30ab12541721 #1 PREEMPT(lazy) ee572ab8f687c1542b07763f9752287d1f4e4afc
[ 32.407911][ T1] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
[ 32.408074][ T1] Call Trace:
[ 32.408201][ T1] <TASK>
[ 32.408359][ T1] dump_stack_lvl (lib/dump_stack.c:122)
[ 32.408918][ T1] lockdep_rcu_suspicious.cold (kernel/locking/lockdep.c:6877)
[ 32.409462][ T1] mas_start (lib/maple_tree.c:780 (discriminator 11) lib/maple_tree.c:1200 (discriminator 11))
[ 32.410053][ T1] mas_walk (lib/maple_tree.c:3291 lib/maple_tree.c:4599)
[ 32.410496][ T1] mas_find (lib/maple_tree.c:5578 lib/maple_tree.c:5618)
[ 32.410919][ T1] dynamic_debug_init (lib/dynamic_debug.c:1780 (discriminator 1))
[ 32.411406][ T1] ? dynamic_debug_init_control (lib/dynamic_debug.c:1739)
[ 32.411658][ T1] ? mix_pool_bytes (drivers/char/random.c:943)
[ 32.411658][ T1] ? ftrace_likely_update (arch/x86/include/asm/smap.h:90 kernel/trace/trace_branch.c:223)
[ 32.411658][ T1] ? dynamic_debug_init_control (lib/dynamic_debug.c:1724)
[ 32.411658][ T1] ? ftrace_likely_update (arch/x86/include/asm/smap.h:90 kernel/trace/trace_branch.c:223)
[ 32.411658][ T1] ? dynamic_debug_init_control (lib/dynamic_debug.c:1739)
[ 32.411658][ T1] do_one_initcall (init/main.c:1378)
[ 32.411658][ T1] ? trace_event_raw_event_initcall_level (init/main.c:1369)
[ 32.411658][ T1] ? ftrace_likely_update (arch/x86/include/asm/smap.h:90 kernel/trace/trace_branch.c:223)
[ 32.411658][ T1] kernel_init_freeable (init/main.c:1483 (discriminator 3) init/main.c:1677 (discriminator 3))
[ 32.411658][ T1] ? rest_init (init/main.c:1570)
[ 32.411658][ T1] kernel_init (init/main.c:1580)
[ 32.411658][ T1] ? rest_init (init/main.c:1570)
[ 32.411658][ T1] ret_from_fork (arch/x86/kernel/process.c:164)
[ 32.411658][ T1] ? exit_thread (arch/x86/kernel/process.c:153)
[ 32.411658][ T1] ? __switch_to (arch/x86/kernel/process_64.c:714)
[ 32.411658][ T1] ? rest_init (init/main.c:1570)
[ 32.411658][ T1] ret_from_fork_asm (arch/x86/entry/entry_64.S:256)
[ 32.411658][ T1] </TASK>
[ 32.411830][ T1]
[ 32.419179][ T1] =============================
[ 32.426199][ T1] WARNING: suspicious RCU usage
[ 32.435290][ T1] 6.19.0-rc6-00038-g30ab12541721 #1 Not tainted
[ 32.445187][ T1] -----------------------------
[ 32.456097][ T1] lib/maple_tree.c:736 suspicious rcu_dereference_check() usage!
[ 32.467775][ T1]
[ 32.467775][ T1] other info that might help us debug this:
[ 32.467775][ T1]
[ 32.480434][ T1]
[ 32.480434][ T1] rcu_scheduler_active = 1, debug_locks = 1
[ 32.488625][ T1] no locks held by swapper/0/1.
[ 32.496517][ T1]
[ 32.496517][ T1] stack backtrace:
[ 32.507460][ T1] CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.19.0-rc6-00038-g30ab12541721 #1 PREEMPT(lazy) ee572ab8f687c1542b07763f9752287d1f4e4afc
[ 32.507944][ T1] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
[ 32.508107][ T1] Call Trace:
[ 32.508235][ T1] <TASK>
[ 32.508394][ T1] dump_stack_lvl (lib/dump_stack.c:122)
[ 32.508885][ T1] lockdep_rcu_suspicious.cold (kernel/locking/lockdep.c:6877)
[ 32.509405][ T1] mtree_range_walk (lib/maple_tree.c:736 (discriminator 11) lib/maple_tree.c:2579 (discriminator 11))
[ 32.510345][ T1] mas_walk (lib/maple_tree.c:3298 lib/maple_tree.c:4599)
[ 32.510799][ T1] mas_find (lib/maple_tree.c:5578 lib/maple_tree.c:5618)
[ 32.511222][ T1] dynamic_debug_init (lib/dynamic_debug.c:1780 (discriminator 1))
[ 32.511658][ T1] ? dynamic_debug_init_control (lib/dynamic_debug.c:1739)
[ 32.511658][ T1] ? mix_pool_bytes (drivers/char/random.c:943)
[ 32.511658][ T1] ? ftrace_likely_update (arch/x86/include/asm/smap.h:90 kernel/trace/trace_branch.c:223)
[ 32.511658][ T1] ? dynamic_debug_init_control (lib/dynamic_debug.c:1724)
[ 32.511658][ T1] ? ftrace_likely_update (arch/x86/include/asm/smap.h:90 kernel/trace/trace_branch.c:223)
[ 32.511658][ T1] ? dynamic_debug_init_control (lib/dynamic_debug.c:1739)
[ 32.511658][ T1] do_one_initcall (init/main.c:1378)
[ 32.511658][ T1] ? trace_event_raw_event_initcall_level (init/main.c:1369)
[ 32.511658][ T1] ? ftrace_likely_update (arch/x86/include/asm/smap.h:90 kernel/trace/trace_branch.c:223)
[ 32.511658][ T1] kernel_init_freeable (init/main.c:1483 (discriminator 3) init/main.c:1677 (discriminator 3))
[ 32.511658][ T1] ? rest_init (init/main.c:1570)
[ 32.511658][ T1] kernel_init (init/main.c:1580)
[ 32.511658][ T1] ? rest_init (init/main.c:1570)
[ 32.511658][ T1] ret_from_fork (arch/x86/kernel/process.c:164)
[ 32.511658][ T1] ? exit_thread (arch/x86/kernel/process.c:153)
[ 32.511658][ T1] ? __switch_to (arch/x86/kernel/process_64.c:714)
[ 32.511658][ T1] ? rest_init (init/main.c:1570)
[ 32.511658][ T1] ret_from_fork_asm (arch/x86/entry/entry_64.S:256)
[ 32.511658][ T1] </TASK>
[ 32.828822][ T1] smp: Bringing up secondary CPUs ...
[ 32.969794][ T1] smpboot: x86: Booting SMP configuration:
[ 32.977793][ T1] .... node #0, CPUs: #1
[ 2.080306][ T0] Masked ExtINT on CPU#1
[ 33.013768][ T1] smp: Brought up 1 node, 2 CPUs
[ 33.036220][ T1] smpboot: Total of 2 processors activated (9575.99 BogoMIPS)
[ 67.945088][ T30] node 0 deferred pages initialised in 34870ms
[ 67.974864][ T1] Memory: 28397356K/33553912K available (63758K kernel code, 23006K rwdata, 18392K rodata, 3328K init, 14332K bss, 5145876K reserved, 0K cma-reserved)
The kernel config and materials to reproduce are available at:
https://download.01.org/0day-ci/archive/20260121/202601211325.c04e2734-lkp@intel.com
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
reply other threads:[~2026-01-21 6:05 UTC|newest]
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