============================= WARNING: suspicious RCU usage syzkaller #0 Not tainted ----------------------------- kernel/sched/core.c:8846 Illegal context switch in RCU-sched read-side critical section! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 4 locks held by syz.7.4502/26956: #0: ffff888115be6340 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:592 [inline] #0: ffff888115be6340 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x124/0xa30 mm/mmap.c:1286 #1: ffffffff896e05a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #1: ffffffff896e05a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #1: ffffffff896e05a0 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x2f/0x300 mm/pgtable-generic.c:288 #2: ffff888124bce5b8 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock.h:341 [inline] #2: ffff888124bce5b8 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: pte_offset_map_lock+0x10f/0x320 mm/pgtable-generic.c:402 #3: ffffffff896e04e0 (rcu_read_lock_sched){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #3: ffffffff896e04e0 (rcu_read_lock_sched){....}-{1:2}, at: rcu_read_lock_sched include/linux/rcupdate.h:948 [inline] #3: ffffffff896e04e0 (rcu_read_lock_sched){....}-{1:2}, at: pfn_valid include/linux/mmzone.h:2197 [inline] #3: ffffffff896e04e0 (rcu_read_lock_sched){....}-{1:2}, at: page_table_check_clear+0x4b/0x9e0 mm/page_table_check.c:70 stack backtrace: CPU: 0 UID: 0 PID: 26956 Comm: syz.7.4502 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 lockdep_rcu_suspicious.cold+0x4f/0xb1 kernel/locking/lockdep.c:6876 __might_resched+0x2e0/0x330 kernel/sched/core.c:8846 usb_kill_urb+0x8e/0x320 drivers/usb/core/urb.c:705 usb_tx_block+0x91/0x320 drivers/net/wireless/marvell/libertas/if_usb.c:429 if_usb_send_fw_pkt.isra.0+0x2e4/0x550 drivers/net/wireless/marvell/libertas/if_usb.c:366 if_usb_receive_fwload+0x5d3/0x780 drivers/net/wireless/marvell/libertas/if_usb.c:592 __usb_hcd_giveback_urb+0x38d/0x610 drivers/usb/core/hcd.c:1657 usb_hcd_giveback_urb+0x3ca/0x4a0 drivers/usb/core/hcd.c:1741 dummy_timer+0xd85/0x3670 drivers/usb/gadget/udc/dummy_hcd.c:1995 __run_hrtimer kernel/time/hrtimer.c:1785 [inline] __hrtimer_run_queues+0x50e/0xa70 kernel/time/hrtimer.c:1849 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1866 handle_softirqs+0x1de/0x9d0 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xed/0x150 kernel/softirq.c:723 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0x8f/0xb0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:lock_acquire+0x5e/0x380 kernel/locking/lockdep.c:5872 Code: 05 bb 1d 66 0b 83 f8 07 0f 87 f0 00 00 00 48 0f a3 05 46 30 61 09 0f 82 c2 02 00 00 8b 35 ee 3f 61 09 85 f6 0f 85 dd 00 00 00 <48> 8b 44 24 30 65 48 2b 05 5d 1d 66 0b 0f 85 02 03 00 00 48 83 c4 RSP: 0018:ffffc90003fdf400 EFLAGS: 00000206 RAX: 0000000000000046 RBX: 0000000000000000 RCX: 0000000000000003 RDX: 0000000000000000 RSI: ffffffff88ffc446 RDI: ffffffff87afa420 RBP: ffffffff896e04e0 R08: 00000000fd65628c R09: 000000000000001e R10: 0000000000000200 R11: 0000000000000000 R12: 0000000000000002 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:312 [inline] rcu_read_lock_sched include/linux/rcupdate.h:948 [inline] pfn_valid include/linux/mmzone.h:2197 [inline] page_table_check_clear+0x67/0x9e0 mm/page_table_check.c:70 __page_table_check_pte_clear+0xf1/0x100 mm/page_table_check.c:155 page_table_check_pte_clear include/linux/page_table_check.h:55 [inline] ptep_get_and_clear_full arch/x86/include/asm/pgtable.h:1271 [inline] get_and_clear_full_ptes include/linux/pgtable.h:846 [inline] zap_present_folio_ptes mm/memory.c:1643 [inline] zap_present_ptes mm/memory.c:1725 [inline] do_zap_pte_range mm/memory.c:1827 [inline] zap_pte_range mm/memory.c:1929 [inline] zap_pmd_range mm/memory.c:2021 [inline] zap_pud_range mm/memory.c:2049 [inline] zap_p4d_range mm/memory.c:2070 [inline] unmap_page_range+0x2283/0x3d80 mm/memory.c:2091 unmap_single_vma+0x153/0x240 mm/memory.c:2133 unmap_vmas+0x295/0x590 mm/memory.c:2171 exit_mmap+0x1ef/0xa30 mm/mmap.c:1302 __mmput kernel/fork.c:1174 [inline] mmput+0xe0/0x430 kernel/fork.c:1197 exit_mm kernel/exit.c:581 [inline] do_exit+0x78a/0x2aa0 kernel/exit.c:959 do_group_exit+0xd5/0x2a0 kernel/exit.c:1112 get_signal+0x1ec7/0x21e0 kernel/signal.c:3034 arch_do_signal_or_restart+0x91/0x7a0 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline] exit_to_user_mode_loop+0x7e/0x430 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline] do_syscall_64+0x671/0x7b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc88df4c42b Code: Unable to access opcode bytes at 0x7fc88df4c401. RSP: 002b:00007fc88c97bf00 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: fffffffffffffffc RBX: 0000000000000003 RCX: 00007fc88df4c42b RDX: 00007fc88c97cfd0 RSI: 0000000080085502 RDI: 0000000000000003 RBP: 00007fc88c97cfd0 R08: 0000000000000008 R09: 00007fc88c97bfc8 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000080085502 R13: 0000000800000000 R14: 0000000000000008 R15: 00007fc88e000bf4 BUG: sleeping function called from invalid context at drivers/usb/core/urb.c:705 in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 26956, name: syz.7.4502 preempt_count: 102, expected: 0 RCU nest depth: 1, expected: 0 4 locks held by syz.7.4502/26956: #0: ffff888115be6340 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:592 [inline] #0: ffff888115be6340 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x124/0xa30 mm/mmap.c:1286 #1: ffffffff896e05a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #1: ffffffff896e05a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #1: ffffffff896e05a0 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x2f/0x300 mm/pgtable-generic.c:288 #2: ffff888124bce5b8 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock.h:341 [inline] #2: ffff888124bce5b8 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: pte_offset_map_lock+0x10f/0x320 mm/pgtable-generic.c:402 #3: ffffffff896e04e0 (rcu_read_lock_sched){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #3: ffffffff896e04e0 (rcu_read_lock_sched){....}-{1:2}, at: rcu_read_lock_sched include/linux/rcupdate.h:948 [inline] #3: ffffffff896e04e0 (rcu_read_lock_sched){....}-{1:2}, at: pfn_valid include/linux/mmzone.h:2197 [inline] #3: ffffffff896e04e0 (rcu_read_lock_sched){....}-{1:2}, at: page_table_check_clear+0x4b/0x9e0 mm/page_table_check.c:70 irq event stamp: 3009 hardirqs last enabled at (3008): [] __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:178 [inline] hardirqs last enabled at (3008): [] _raw_spin_unlock_irqrestore+0x52/0x80 kernel/locking/spinlock.c:194 hardirqs last disabled at (3009): [] __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:130 [inline] hardirqs last disabled at (3009): [] _raw_spin_lock_irqsave+0x52/0x60 kernel/locking/spinlock.c:162 softirqs last enabled at (3002): [] __do_softirq kernel/softirq.c:656 [inline] softirqs last enabled at (3002): [] invoke_softirq kernel/softirq.c:496 [inline] softirqs last enabled at (3002): [] __irq_exit_rcu+0xed/0x150 kernel/softirq.c:723 softirqs last disabled at (3005): [] __do_softirq kernel/softirq.c:656 [inline] softirqs last disabled at (3005): [] invoke_softirq kernel/softirq.c:496 [inline] softirqs last disabled at (3005): [] __irq_exit_rcu+0xed/0x150 kernel/softirq.c:723 Preemption disabled at: [<0000000000000000>] 0x0 CPU: 0 UID: 0 PID: 26956 Comm: syz.7.4502 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 __might_resched.cold+0x1ec/0x232 kernel/sched/core.c:8884 usb_kill_urb+0x8e/0x320 drivers/usb/core/urb.c:705 usb_tx_block+0x91/0x320 drivers/net/wireless/marvell/libertas/if_usb.c:429 if_usb_send_fw_pkt.isra.0+0x2e4/0x550 drivers/net/wireless/marvell/libertas/if_usb.c:366 if_usb_receive_fwload+0x5d3/0x780 drivers/net/wireless/marvell/libertas/if_usb.c:592 __usb_hcd_giveback_urb+0x38d/0x610 drivers/usb/core/hcd.c:1657 usb_hcd_giveback_urb+0x3ca/0x4a0 drivers/usb/core/hcd.c:1741 dummy_timer+0xd85/0x3670 drivers/usb/gadget/udc/dummy_hcd.c:1995 __run_hrtimer kernel/time/hrtimer.c:1785 [inline] __hrtimer_run_queues+0x50e/0xa70 kernel/time/hrtimer.c:1849 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1866 handle_softirqs+0x1de/0x9d0 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xed/0x150 kernel/softirq.c:723 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0x8f/0xb0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:lock_acquire+0x5e/0x380 kernel/locking/lockdep.c:5872 Code: 05 bb 1d 66 0b 83 f8 07 0f 87 f0 00 00 00 48 0f a3 05 46 30 61 09 0f 82 c2 02 00 00 8b 35 ee 3f 61 09 85 f6 0f 85 dd 00 00 00 <48> 8b 44 24 30 65 48 2b 05 5d 1d 66 0b 0f 85 02 03 00 00 48 83 c4 RSP: 0018:ffffc90003fdf400 EFLAGS: 00000206 RAX: 0000000000000046 RBX: 0000000000000000 RCX: 0000000000000003 RDX: 0000000000000000 RSI: ffffffff88ffc446 RDI: ffffffff87afa420 RBP: ffffffff896e04e0 R08: 00000000fd65628c R09: 000000000000001e R10: 0000000000000200 R11: 0000000000000000 R12: 0000000000000002 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:312 [inline] rcu_read_lock_sched include/linux/rcupdate.h:948 [inline] pfn_valid include/linux/mmzone.h:2197 [inline] page_table_check_clear+0x67/0x9e0 mm/page_table_check.c:70 __page_table_check_pte_clear+0xf1/0x100 mm/page_table_check.c:155 page_table_check_pte_clear include/linux/page_table_check.h:55 [inline] ptep_get_and_clear_full arch/x86/include/asm/pgtable.h:1271 [inline] get_and_clear_full_ptes include/linux/pgtable.h:846 [inline] zap_present_folio_ptes mm/memory.c:1643 [inline] zap_present_ptes mm/memory.c:1725 [inline] do_zap_pte_range mm/memory.c:1827 [inline] zap_pte_range mm/memory.c:1929 [inline] zap_pmd_range mm/memory.c:2021 [inline] zap_pud_range mm/memory.c:2049 [inline] zap_p4d_range mm/memory.c:2070 [inline] unmap_page_range+0x2283/0x3d80 mm/memory.c:2091 unmap_single_vma+0x153/0x240 mm/memory.c:2133 unmap_vmas+0x295/0x590 mm/memory.c:2171 exit_mmap+0x1ef/0xa30 mm/mmap.c:1302 __mmput kernel/fork.c:1174 [inline] mmput+0xe0/0x430 kernel/fork.c:1197 exit_mm kernel/exit.c:581 [inline] do_exit+0x78a/0x2aa0 kernel/exit.c:959 do_group_exit+0xd5/0x2a0 kernel/exit.c:1112 get_signal+0x1ec7/0x21e0 kernel/signal.c:3034 arch_do_signal_or_restart+0x91/0x7a0 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline] exit_to_user_mode_loop+0x7e/0x430 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline] do_syscall_64+0x671/0x7b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc88df4c42b Code: Unable to access opcode bytes at 0x7fc88df4c401. RSP: 002b:00007fc88c97bf00 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: fffffffffffffffc RBX: 0000000000000003 RCX: 00007fc88df4c42b RDX: 00007fc88c97cfd0 RSI: 0000000080085502 RDI: 0000000000000003 RBP: 00007fc88c97cfd0 R08: 0000000000000008 R09: 00007fc88c97bfc8 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000080085502 R13: 0000000800000000 R14: 0000000000000008 R15: 00007fc88e000bf4 BUG: scheduling while atomic: syz.7.4502/26956/0x00000103 4 locks held by syz.7.4502/26956: #0: ffff888115be6340 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:592 [inline] #0: ffff888115be6340 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x124/0xa30 mm/mmap.c:1286 #1: ffffffff896e05a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #1: ffffffff896e05a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #1: ffffffff896e05a0 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x2f/0x300 mm/pgtable-generic.c:288 #2: ffff888124bce5b8 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock.h:341 [inline] #2: ffff888124bce5b8 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: pte_offset_map_lock+0x10f/0x320 mm/pgtable-generic.c:402 #3: ffffffff896e04e0 (rcu_read_lock_sched){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #3: ffffffff896e04e0 (rcu_read_lock_sched){....}-{1:2}, at: rcu_read_lock_sched include/linux/rcupdate.h:948 [inline] #3: ffffffff896e04e0 (rcu_read_lock_sched){....}-{1:2}, at: pfn_valid include/linux/mmzone.h:2197 [inline] #3: ffffffff896e04e0 (rcu_read_lock_sched){....}-{1:2}, at: page_table_check_clear+0x4b/0x9e0 mm/page_table_check.c:70 Modules linked in: irq event stamp: 3009 hardirqs last enabled at (3008): [] __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:178 [inline] hardirqs last enabled at (3008): [] _raw_spin_unlock_irqrestore+0x52/0x80 kernel/locking/spinlock.c:194 hardirqs last disabled at (3009): [] __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:130 [inline] hardirqs last disabled at (3009): [] _raw_spin_lock_irqsave+0x52/0x60 kernel/locking/spinlock.c:162 softirqs last enabled at (3002): [] __do_softirq kernel/softirq.c:656 [inline] softirqs last enabled at (3002): [] invoke_softirq kernel/softirq.c:496 [inline] softirqs last enabled at (3002): [] __irq_exit_rcu+0xed/0x150 kernel/softirq.c:723 softirqs last disabled at (3005): [] __do_softirq kernel/softirq.c:656 [inline] softirqs last disabled at (3005): [] invoke_softirq kernel/softirq.c:496 [inline] softirqs last disabled at (3005): [] __irq_exit_rcu+0xed/0x150 kernel/softirq.c:723 Preemption disabled at: [<0000000000000000>] 0x0 ---------------- Code disassembly (best guess): 0: 05 bb 1d 66 0b add $0xb661dbb,%eax 5: 83 f8 07 cmp $0x7,%eax 8: 0f 87 f0 00 00 00 ja 0xfe e: 48 0f a3 05 46 30 61 bt %rax,0x9613046(%rip) # 0x961305c 15: 09 16: 0f 82 c2 02 00 00 jb 0x2de 1c: 8b 35 ee 3f 61 09 mov 0x9613fee(%rip),%esi # 0x9614010 22: 85 f6 test %esi,%esi 24: 0f 85 dd 00 00 00 jne 0x107 * 2a: 48 8b 44 24 30 mov 0x30(%rsp),%rax <-- trapping instruction 2f: 65 48 2b 05 5d 1d 66 sub %gs:0xb661d5d(%rip),%rax # 0xb661d94 36: 0b 37: 0f 85 02 03 00 00 jne 0x33f 3d: 48 rex.W 3e: 83 .byte 0x83 3f: c4 .byte 0xc4