vhci_hcd vhci_hcd.0: Device attached
==================================================================
BUG: KCSAN: data-race in data_alloc / prb_reserve

write to 0xffffffff86874078 of 8 bytes by task 22412 on cpu 0:
 data_alloc+0x280/0x2e0 kernel/printk/printk_ringbuffer.c:1102
 prb_reserve+0x807/0xaf0 kernel/printk/printk_ringbuffer.c:1685
 vprintk_store+0x56d/0x860 kernel/printk/printk.c:2299
 vprintk_emit+0x10d/0x580 kernel/printk/printk.c:2399
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2438
 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82
 _printk+0x79/0xa0 kernel/printk/printk.c:2448
 buffer_io_error fs/buffer.c:130 [inline]
 end_buffer_async_read fs/buffer.c:271 [inline]
 end_buffer_async_read_io+0x232/0x250 fs/buffer.c:380
 end_bio_bh_io_sync+0x79/0xa0 fs/buffer.c:2776
 bio_endio+0x37e/0x420 block/bio.c:1672
 blk_mq_submit_bio+0x3d3/0x1100 block/blk-mq.c:-1
 __submit_bio+0xed/0x4d0 block/blk-core.c:637
 __submit_bio_noacct_mq block/blk-core.c:724 [inline]
 submit_bio_noacct_nocheck+0x152/0x5c0 block/blk-core.c:755
 submit_bio_noacct+0x746/0x9a0 block/blk-core.c:879
 submit_bio+0x2a6/0x2c0 block/blk-core.c:921
 submit_bh_wbc+0x2e0/0x320 fs/buffer.c:2824
 submit_bh fs/buffer.c:2829 [inline]
 block_read_full_folio+0x658/0x6a0 fs/buffer.c:2461
 blkdev_read_folio+0x1c/0x30 block/fops.c:499
 filemap_read_folio mm/filemap.c:2444 [inline]
 do_read_cache_folio+0x196/0x5b0 mm/filemap.c:4024
 read_cache_folio+0x3c/0x50 mm/filemap.c:4056
 read_mapping_folio include/linux/pagemap.h:999 [inline]
 read_part_sector+0x6f/0x150 block/partitions/core.c:722
 read_lba+0x100/0x1e0 block/partitions/efi.c:248
 find_valid_gpt block/partitions/efi.c:603 [inline]
 efi_partition+0x1ea/0x1400 block/partitions/efi.c:720
 check_partition block/partitions/core.c:141 [inline]
 blk_add_partitions block/partitions/core.c:589 [inline]
 bdev_disk_changed+0x4b9/0xcb0 block/partitions/core.c:693
 loop_reread_partitions+0x48/0xb0 drivers/block/loop.c:449
 loop_configure+0x981/0x9c0 drivers/block/loop.c:1098
 lo_ioctl+0x5aa/0x12b0 drivers/block/loop.c:1544
 blkdev_ioctl+0x356/0x440 block/ioctl.c:705
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0xce/0x140 fs/ioctl.c:583
 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:583
 x64_sys_call+0x1816/0x3000 arch/x86/include/generated/asm/syscalls_64.h:17
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffffff86874078 of 8 bytes by task 22392 on cpu 1:
 desc_read kernel/printk/printk_ringbuffer.c:479 [inline]
 desc_push_tail kernel/printk/printk_ringbuffer.c:775 [inline]
 desc_reserve kernel/printk/printk_ringbuffer.c:921 [inline]
 prb_reserve+0x220/0xaf0 kernel/printk/printk_ringbuffer.c:1635
 vprintk_store+0x56d/0x860 kernel/printk/printk.c:2299
 vprintk_emit+0x10d/0x580 kernel/printk/printk.c:2399
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2438
 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82
 _printk+0x79/0xa0 kernel/printk/printk.c:2448
 valid_args drivers/usb/usbip/vhci_sysfs.c:289 [inline]
 attach_store+0x36b/0x680 drivers/usb/usbip/vhci_sysfs.c:341
 dev_attr_store+0x4a/0x70 drivers/base/core.c:2437
 sysfs_kf_write+0xfe/0x120 fs/sysfs/file.c:142
 kernfs_fop_write_iter+0x1eb/0x300 fs/kernfs/file.c:352
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0x52a/0x960 fs/read_write.c:686
 ksys_write+0xda/0x1a0 fs/read_write.c:738
 __do_sys_write fs/read_write.c:749 [inline]
 __se_sys_write fs/read_write.c:746 [inline]
 __x64_sys_write+0x40/0x50 fs/read_write.c:746
 x64_sys_call+0x2802/0x3000 arch/x86/include/generated/asm/syscalls_64.h:2
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0xfffffffffffe3678 -> 0x0000000000099fb8

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 22392 Comm: syz.8.4984 Not tainted syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
==================================================================
vhci_hcd: Failed attach request for unsupported USB speed: UNKNOWN
vhci_hcd vhci_hcd.0: pdev(8) rhport(0) sockfd(25)
vhci_hcd vhci_hcd.0: devid(0) speed(5) speed_str(super-speed)
vhci_hcd vhci_hcd.0: Device attached
vhci_hcd: Failed attach request for unsupported USB speed: UNKNOWN
vhci_hcd vhci_hcd.0: pdev(8) rhport(6) sockfd(31)
vhci_hcd vhci_hcd.0: devid(0) speed(3) speed_str(high-speed)
vhci_hcd vhci_hcd.0: Device attached
vhci_hcd: Failed attach request for unsupported USB speed: UNKNOWN