Re: [PATCH 2/2] mm: mempolicy: Interleave policy for tiered memory nodes

[kernel test robot]

Hello,

kernel test robot noticed "WARNING:suspicious_RCU_usage" on:

commit: 8536fe0dad4ce46984d207cd53583e7c36bc94b1 ("[PATCH 2/2] mm: mempolicy: Interleave policy for tiered memory nodes")
url: https://github.com/intel-lab-lkp/linux/commits/Ravi-Jonnalagadda/memory-tier-Introduce-sysfs-for-tier-interleave-weights/20230927-175208
base: https://git.kernel.org/cgit/linux/kernel/git/tip/tip.git 612f769edd06a6e42f7cd72425488e68ddaeef0a
patch link: https://lore.kernel.org/all/20230927095002.10245-3-ravis.opensrc@xxxxxxxxxx/
patch subject: [PATCH 2/2] mm: mempolicy: Interleave policy for tiered memory nodes

in testcase: boot

compiler: gcc-12
test machine: qemu-system-x86_64 -enable-kvm -cpu SandyBridge -smp 2 -m 16G

(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/202310210005.51e08d62-oliver.sang@xxxxxxxxx


[    3.474923][    T0] WARNING: suspicious RCU usage
[    3.476322][    T0] 6.6.0-rc1-00038-g8536fe0dad4c #2 Not tainted
[    3.478100][    T0] -----------------------------
[    3.480319][    T0] mm/memory-tiers.c:258 suspicious rcu_dereference_check() usage!
[    3.482562][    T0]
[    3.482562][    T0] other info that might help us debug this:
[    3.482562][    T0]
[    3.484325][    T0]
[    3.484325][    T0] rcu_scheduler_active = 1, debug_locks = 1
[    3.488321][    T0] no locks held by swapper/0/0.
[    3.489732][    T0]
[    3.489732][    T0] stack backtrace:
[    3.491424][    T0] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.6.0-rc1-00038-g8536fe0dad4c #2
[    3.492304][    T0] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
[    3.492304][    T0] Call Trace:
[    3.492304][    T0]  <TASK>
[ 3.492304][ T0] dump_stack_lvl (kbuild/src/rand-x86_64-3/lib/dump_stack.c:107) 
[ 3.492304][ T0] lockdep_rcu_suspicious (kbuild/src/rand-x86_64-3/include/linux/context_tracking.h:153 kbuild/src/rand-x86_64-3/kernel/locking/lockdep.c:6712) 
[ 3.492304][ T0] node_get_memory_tier (kbuild/src/rand-x86_64-3/mm/memory-tiers.c:258 (discriminator 11)) 
[ 3.492304][ T0] node_interleave_weight (kbuild/src/rand-x86_64-3/mm/mempolicy.c:1921) 
[ 3.492304][ T0] ? __orc_find (kbuild/src/rand-x86_64-3/arch/x86/kernel/unwind_orc.c:110) 
[ 3.492304][ T0] ? secondary_startup_64_no_verify (kbuild/src/rand-x86_64-3/arch/x86/kernel/head_64.S:433) 
[ 3.492304][ T0] ? orc_find (kbuild/src/rand-x86_64-3/arch/x86/kernel/unwind_orc.c:242) 
[ 3.492304][ T0] ? secondary_startup_64_no_verify (kbuild/src/rand-x86_64-3/arch/x86/kernel/head_64.S:433) 
[ 3.492304][ T0] ? secondary_startup_64_no_verify (kbuild/src/rand-x86_64-3/arch/x86/kernel/head_64.S:433) 
[ 3.492304][ T0] ? unwind_next_frame (kbuild/src/rand-x86_64-3/arch/x86/kernel/unwind_orc.c:682) 
[ 3.492304][ T0] interleave_nodes (kbuild/src/rand-x86_64-3/mm/mempolicy.c:1969) 
[ 3.492304][ T0] mempolicy_slab_node (kbuild/src/rand-x86_64-3/mm/mempolicy.c:2007) 
[ 3.492304][ T0] __slab_alloc_node+0x195/0x320 
[ 3.492304][ T0] slab_alloc_node+0x67/0x160 
[ 3.492304][ T0] kmem_cache_alloc_node (kbuild/src/rand-x86_64-3/mm/slub.c:3525) 
[ 3.492304][ T0] dup_task_struct (kbuild/src/rand-x86_64-3/kernel/fork.c:173 kbuild/src/rand-x86_64-3/kernel/fork.c:1110) 
[ 3.492304][ T0] copy_process (kbuild/src/rand-x86_64-3/kernel/fork.c:2327) 
[ 3.492304][ T0] ? kvm_sched_clock_read (kbuild/src/rand-x86_64-3/arch/x86/kernel/kvmclock.c:91) 
[ 3.492304][ T0] kernel_clone (kbuild/src/rand-x86_64-3/include/linux/random.h:26 kbuild/src/rand-x86_64-3/kernel/fork.c:2910) 
[ 3.492304][ T0] ? rest_init (kbuild/src/rand-x86_64-3/init/main.c:1429) 
[ 3.492304][ T0] user_mode_thread (kbuild/src/rand-x86_64-3/kernel/fork.c:2988) 
[ 3.492304][ T0] ? rest_init (kbuild/src/rand-x86_64-3/init/main.c:1429) 
[ 3.492304][ T0] rest_init (kbuild/src/rand-x86_64-3/init/main.c:691) 
[ 3.492304][ T0] ? acpi_enable_subsystem (kbuild/src/rand-x86_64-3/drivers/acpi/acpica/utxfinit.c:192) 
[ 3.492304][ T0] arch_call_rest_init+0xf/0x20 
[ 3.492304][ T0] start_kernel (kbuild/src/rand-x86_64-3/init/main.c:1019 (discriminator 1)) 
[ 3.492304][ T0] x86_64_start_reservations (kbuild/src/rand-x86_64-3/arch/x86/kernel/head64.c:544) 
[ 3.492304][ T0] x86_64_start_kernel (kbuild/src/rand-x86_64-3/arch/x86/kernel/head64.c:486 (discriminator 17)) 
[ 3.492304][ T0] secondary_startup_64_no_verify (kbuild/src/rand-x86_64-3/arch/x86/kernel/head_64.S:433) 
[    3.492304][    T0]  </TASK>



The kernel config and materials to reproduce are available at:
https://download.01.org/0day-ci/archive/20231021/202310210005.51e08d62-oliver.sang@xxxxxxxxx



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