[jimc:dd-shrink] [dyndbg] 30ab125417: WARNING:suspicious_RCU_usage

kernel test robot <[email protected]>
Newsgroups dev.linux.lists.oe-lkp
Message-ID <[email protected]> 

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 <[email protected]>
| Closes: https://lore.kernel.org/oe-lkp/[email protected]



[   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/[email protected]



-- 
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