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BUG: KCSAN: data-race in detach_buf_split / virtqueue_add

read to 0xffff88810232ba2c of 4 bytes by task 16070 on cpu 0:
 virtqueue_add_split drivers/virtio/virtio_ring.c:575 [inline]
 virtqueue_add+0x75a/0x20e0 drivers/virtio/virtio_ring.c:2133
 virtqueue_add_inbuf+0x53/0x80 drivers/virtio/virtio_ring.c:2212
 request_entropy drivers/char/hw_random/virtio-rng.c:61 [inline]
 copy_data drivers/char/hw_random/virtio-rng.c:74 [inline]
 virtio_read+0x1c5/0x3f0 drivers/char/hw_random/virtio-rng.c:92
 rng_get_data drivers/char/hw_random/core.c:197 [inline]
 rng_dev_read+0x1a7/0x5e0 drivers/char/hw_random/core.c:234
 vfs_read+0x19e/0x580 fs/read_write.c:468
 ksys_read+0xeb/0x1a0 fs/read_write.c:613
 __do_sys_read fs/read_write.c:623 [inline]
 __se_sys_read fs/read_write.c:621 [inline]
 __x64_sys_read+0x42/0x50 fs/read_write.c:621
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read-write to 0xffff88810232ba2c of 4 bytes by interrupt on cpu 1:
 detach_buf_split+0x316/0x570 drivers/virtio/virtio_ring.c:760
 virtqueue_get_buf_ctx_split drivers/virtio/virtio_ring.c:835 [inline]
 virtqueue_get_buf_ctx+0x3c2/0x5b0 drivers/virtio/virtio_ring.c:2327
 virtqueue_get_buf+0x1f/0x30 drivers/virtio/virtio_ring.c:2333
 random_recv_done+0x4c/0x90 drivers/char/hw_random/virtio-rng.c:42
 vring_interrupt+0x150/0x170 drivers/virtio/virtio_ring.c:2501
 __handle_irq_event_percpu+0x91/0x490 kernel/irq/handle.c:158
 handle_irq_event_percpu kernel/irq/handle.c:193 [inline]
 handle_irq_event+0x64/0xf0 kernel/irq/handle.c:210
 handle_edge_irq+0x167/0x590 kernel/irq/chip.c:819
 generic_handle_irq_desc include/linux/irqdesc.h:158 [inline]
 handle_irq arch/x86/kernel/irq.c:231 [inline]
 __common_interrupt+0x3c/0xb0 arch/x86/kernel/irq.c:250
 common_interrupt+0x3d/0x90 arch/x86/kernel/irq.c:240
 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:636
 __sanitizer_cov_trace_const_cmp8+0x0/0x80 kernel/kcov.c:306
 pie_calculate_probability+0x412/0x520
 fq_pie_timer+0xbc/0x150 net/sched/sch_fq_pie.c:387
 call_timer_fn+0x35/0x290 kernel/time/timer.c:1700
 expire_timers kernel/time/timer.c:1751 [inline]
 __run_timers+0x46c/0x650 kernel/time/timer.c:2022
 run_timer_softirq+0x1d/0x40 kernel/time/timer.c:2035
 __do_softirq+0xc1/0x265 kernel/softirq.c:571
 invoke_softirq kernel/softirq.c:445 [inline]
 __irq_exit_rcu+0x57/0xa0 kernel/softirq.c:650
 common_interrupt+0x7f/0x90 arch/x86/kernel/irq.c:240
 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:636
 to_kthread kernel/kthread.c:76 [inline]
 kthread_should_stop+0x1e/0x80 kernel/kthread.c:158
 smpboot_thread_fn+0x348/0x4a0 kernel/smpboot.c:114
 kthread+0x1d7/0x210 kernel/kthread.c:379
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308

value changed: 0x000000ff -> 0x000000fe

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 19 Comm: ksoftirqd/1 Tainted: G        W          6.4.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023
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