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BUG: KCSAN: data-race in random_recv_done / virtio_read

write to 0xffff888100bd48cc of 4 bytes by interrupt on cpu 1:
 random_recv_done+0x58/0x80 drivers/char/hw_random/virtio-rng.c:45
 vring_interrupt+0x15d/0x180 drivers/virtio/virtio_ring.c:2163
 __handle_irq_event_percpu+0x93/0x480 kernel/irq/handle.c:158
 handle_irq_event_percpu kernel/irq/handle.c:198 [inline]
 handle_irq_event+0x9a/0x150 kernel/irq/handle.c:215
 handle_edge_irq+0x18e/0x5f0 kernel/irq/chip.c:822
 generic_handle_irq_desc include/linux/irqdesc.h:158 [inline]
 handle_irq arch/x86/kernel/irq.c:231 [inline]
 __common_interrupt+0x60/0x100 arch/x86/kernel/irq.c:250
 common_interrupt+0x9a/0xc0 arch/x86/kernel/irq.c:240
 asm_common_interrupt+0x1e/0x40
 kcsan_setup_watchpoint+0x94/0x420 kernel/kcsan/core.c:443
 batadv_nc_purge_paths+0x9a/0x2c0 net/batman-adv/network-coding.c:447
 batadv_nc_worker+0x163/0xa00 net/batman-adv/network-coding.c:724
 process_one_work+0x3fc/0x980 kernel/workqueue.c:2298
 worker_thread+0x616/0xa70 kernel/workqueue.c:2445
 kthread+0x2c7/0x2e0 kernel/kthread.c:327
 ret_from_fork+0x1f/0x30

write to 0xffff888100bd48cc of 4 bytes by task 19125 on cpu 0:
 request_entropy drivers/char/hw_random/virtio-rng.c:56 [inline]
 copy_data drivers/char/hw_random/virtio-rng.c:74 [inline]
 virtio_read+0x1a0/0x450 drivers/char/hw_random/virtio-rng.c:92
 rng_get_data drivers/char/hw_random/core.c:192 [inline]
 rng_dev_read+0x1b4/0x630 drivers/char/hw_random/core.c:229
 loop_rw_iter+0x257/0x350
 io_iter_do_read fs/io_uring.c:3507 [inline]
 io_read fs/io_uring.c:3562 [inline]
 io_issue_sqe+0x521e/0x55e0 fs/io_uring.c:6675
 io_wq_submit_work+0x1c5/0x370 fs/io_uring.c:6840
 io_worker_handle_work+0x4ca/0xbd0 fs/io-wq.c:576
 io_wqe_worker+0x1bc/0x4f0 fs/io-wq.c:632
 ret_from_fork+0x1f/0x30

value changed: 0x00000040 -> 0x00000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 19125 Comm: iou-wrk-19113 Not tainted 5.16.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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