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BUG: KCSAN: data-race in desc_read_finalized_seq / prb_reserve

write to 0xffffffff868b62e0 of 8 bytes by task 14437 on cpu 1:
 prb_reserve+0x750/0xb80 kernel/printk/printk_ringbuffer.c:-1
 vprintk_store+0x552/0x860 kernel/printk/printk.c:2326
 vprintk_emit+0x1a0/0x6c0 kernel/printk/printk.c:2426
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2465
 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82
 _printk+0x7f/0xb0 kernel/printk/printk.c:2475
 __ext4_error+0x259/0x340 fs/ext4/super.c:817
 ext4_orphan_get+0x18b/0x400 fs/ext4/ialloc.c:1393
 ext4_orphan_cleanup+0x5e3/0x9f0 fs/ext4/orphan.c:467
 __ext4_fill_super fs/ext4/super.c:5607 [inline]
 ext4_fill_super+0x3215/0x3580 fs/ext4/super.c:5726
 get_tree_bdev_flags+0x2b4/0x330 fs/super.c:1636
 get_tree_bdev+0x1f/0x30 fs/super.c:1659
 ext4_get_tree+0x1c/0x30 fs/ext4/super.c:5758
 vfs_get_tree+0x56/0x1e0 fs/super.c:1759
 do_new_mount+0x246/0x6b0 fs/namespace.c:3879
 path_mount+0x49b/0xb30 fs/namespace.c:4206
 do_mount fs/namespace.c:4219 [inline]
 __do_sys_mount fs/namespace.c:4430 [inline]
 __se_sys_mount+0x28f/0x2e0 fs/namespace.c:4407
 __x64_sys_mount+0x67/0x80 fs/namespace.c:4407
 x64_sys_call+0xd11/0x2e10 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffffff868b62e0 of 8 bytes by task 14439 on cpu 0:
 desc_read kernel/printk/printk_ringbuffer.c:486 [inline]
 desc_read_finalized_seq+0x163/0x280 kernel/printk/printk_ringbuffer.c:1874
 prb_read kernel/printk/printk_ringbuffer.c:1922 [inline]
 _prb_read_valid+0x142/0x710 kernel/printk/printk_ringbuffer.c:2113
 desc_update_last_finalized kernel/printk/printk_ringbuffer.c:1515 [inline]
 prb_final_commit+0x147/0x200 kernel/printk/printk_ringbuffer.c:1782
 vprintk_store+0x737/0x860 kernel/printk/printk.c:2352
 vprintk_emit+0x1a0/0x6c0 kernel/printk/printk.c:2426
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2465
 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82
 _printk+0x7f/0xb0 kernel/printk/printk.c:2475
 usb_find_alt_setting+0x178/0x180 drivers/usb/core/usb.c:320
 check_ctrlrecip+0x109/0x7b0 drivers/usb/core/devio.c:900
 do_proc_control+0x83/0x890 drivers/usb/core/devio.c:1180
 proc_control_compat drivers/usb/core/devio.c:2148 [inline]
 usbdev_do_ioctl drivers/usb/core/devio.c:2712 [inline]
 usbdev_ioctl+0x27e4/0x3e70 drivers/usb/core/devio.c:2827
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:906 [inline]
 __se_sys_ioctl+0xc9/0x140 fs/ioctl.c:892
 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:892
 x64_sys_call+0x168d/0x2e10 arch/x86/include/generated/asm/syscalls_64.h:17
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000000000000530 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 14439 Comm: syz.6.3858 Not tainted 6.15.0-rc1-syzkaller-00065-g3b07108ada81 #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
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usb usb9: usbfs: process 14439 (syz.6.3858) did not claim interface 63 before use