================================================================== BUG: KCSAN: data-race in data_alloc / prb_reserve write to 0xffffffff86086a40 of 8 bytes by task 19263 on cpu 1: data_alloc+0x291/0x2c0 kernel/printk/printk_ringbuffer.c:1096 prb_reserve+0x85e/0xb60 kernel/printk/printk_ringbuffer.c:1669 vprintk_store+0x53f/0x810 kernel/printk/printk.c:2269 vprintk_emit+0x10c/0x5e0 kernel/printk/printk.c:2329 vprintk_default+0x26/0x30 kernel/printk/printk.c:2363 vprintk+0x75/0x80 kernel/printk/printk_safe.c:45 _printk+0x7a/0xa0 kernel/printk/printk.c:2373 vhci_rx_pdu drivers/usb/usbip/vhci_rx.c:224 [inline] vhci_rx_loop+0x4d1/0x980 drivers/usb/usbip/vhci_rx.c:265 kthread+0x1d1/0x210 kernel/kthread.c:389 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 read to 0xffffffff86086a40 of 8 bytes by task 19259 on cpu 0: desc_read kernel/printk/printk_ringbuffer.c:482 [inline] desc_push_tail kernel/printk/printk_ringbuffer.c:778 [inline] desc_reserve kernel/printk/printk_ringbuffer.c:924 [inline] prb_reserve+0x235/0xb60 kernel/printk/printk_ringbuffer.c:1619 vprintk_store+0x53f/0x810 kernel/printk/printk.c:2269 vprintk_emit+0x10c/0x5e0 kernel/printk/printk.c:2329 vprintk_default+0x26/0x30 kernel/printk/printk.c:2363 vprintk+0x75/0x80 kernel/printk/printk_safe.c:45 _printk+0x7a/0xa0 kernel/printk/printk.c:2373 vhci_rx_pdu drivers/usb/usbip/vhci_rx.c:224 [inline] vhci_rx_loop+0x4d1/0x980 drivers/usb/usbip/vhci_rx.c:265 kthread+0x1d1/0x210 kernel/kthread.c:389 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 value changed: 0x000000000003df50 -> 0x00000000000ec5b8 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 19259 Comm: vhci_rx Not tainted 6.10.0-rc6-syzkaller-00069-g795c58e4c7fc #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 ================================================================== vhci_hcd: connection closed