=====================================================
BUG: KMSAN: uninit-value in __flush_smp_call_function_queue+0x343/0x1810 kernel/smp.c:549
 __flush_smp_call_function_queue+0x343/0x1810 kernel/smp.c:549
 generic_smp_call_function_single_interrupt+0x1c/0x30 kernel/smp.c:477
 __sysvec_call_function_single+0x48/0x350 arch/x86/kernel/smp.c:272
 instr_sysvec_call_function_single arch/x86/kernel/smp.c:267 [inline]
 sysvec_call_function_single+0x7c/0x90 arch/x86/kernel/smp.c:267
 asm_sysvec_call_function_single+0x1f/0x30 arch/x86/include/asm/idtentry.h:704
 kmsan_internal_set_shadow_origin+0x9a/0x110 mm/kmsan/core.c:233
 __msan_poison_alloca+0x14f/0x1a0 mm/kmsan/instrumentation.c:289
 __do_compat_sys_wait4 kernel/exit.c:1939 [inline]
 __se_compat_sys_wait4 kernel/exit.c:1933 [inline]
 __ia32_compat_sys_wait4+0xaa/0x340 kernel/exit.c:1933
 ia32_sys_call+0x3e4b/0x4360 arch/x86/include/generated/asm/syscalls_32.h:115
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 do_int80_emulation+0x177/0x380 arch/x86/entry/syscall_32.c:172
 asm_int80_emulation+0x1f/0x30 arch/x86/include/asm/idtentry.h:621

Local variable waiter created at:
 rwsem_down_read_slowpath+0x44/0x12b0 kernel/locking/rwsem.c:1021
 __down_read_common kernel/locking/rwsem.c:1291 [inline]
 __down_read_killable kernel/locking/rwsem.c:1314 [inline]
 down_read_killable+0x92/0x2a0 kernel/locking/rwsem.c:1595

CPU: 1 UID: 0 PID: 5578 Comm: syz-executor Tainted: G             L      syzkaller #0 PREEMPT(lazy) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
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