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BUG: KCSAN: data-race in random_recv_done / virtio_read

write to 0xffff888101c19ecc 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:2148
 __handle_irq_event_percpu+0x92/0x400 kernel/irq/handle.c:158
 handle_irq_event_percpu kernel/irq/handle.c:193 [inline]
 handle_irq_event+0x60/0xf0 kernel/irq/handle.c:210
 handle_edge_irq+0x17e/0x5a0 kernel/irq/chip.c:817
 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
 check_access kernel/kcsan/core.c:726 [inline]
 __tsan_read4+0x20/0x180 kernel/kcsan/core.c:1013
 crc32_body lib/crc32.c:106 [inline]
 crc32_le_generic lib/crc32.c:179 [inline]
 __crc32c_le_base+0xa9/0x490 lib/crc32.c:201
 chksum_update+0x2e/0x50 crypto/crct10dif_generic.c:56
 crypto_shash_update+0x13c/0x1a0 crypto/shash.c:131
 ext4_chksum fs/ext4/ext4.h:2458 [inline]
 ext4_block_bitmap_csum_set+0xca/0x190 fs/ext4/bitmap.c:94
 ext4_mb_mark_diskspace_used+0x538/0x710 fs/ext4/mballoc.c:3858
 ext4_mb_new_blocks+0x6f5/0xae0 fs/ext4/mballoc.c:5634
 ext4_ext_map_blocks+0x9e2/0x1560 fs/ext4/extents.c:4281
 ext4_map_blocks+0x57e/0xbb0 fs/ext4/inode.c:636
 ext4_alloc_file_blocks+0x1b3/0x580 fs/ext4/extents.c:4466
 ext4_fallocate+0x2eb/0x3a0 fs/ext4/extents.c:4751
 vfs_fallocate+0x355/0x3d0 fs/open.c:308
 ksys_fallocate fs/open.c:331 [inline]
 __do_sys_fallocate fs/open.c:339 [inline]
 __se_sys_fallocate fs/open.c:337 [inline]
 __x64_sys_fallocate+0x75/0xc0 fs/open.c:337
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

write to 0xffff888101c19ecc of 4 bytes by task 20795 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+0x190/0x430 drivers/char/hw_random/virtio-rng.c:92
 rng_get_data drivers/char/hw_random/core.c:191 [inline]
 rng_dev_read+0x1b4/0x630 drivers/char/hw_random/core.c:228
 vfs_read+0x1a1/0x6a0 fs/read_write.c:480
 ksys_read+0xe8/0x1a0 fs/read_write.c:620
 __do_sys_read fs/read_write.c:630 [inline]
 __se_sys_read fs/read_write.c:628 [inline]
 __x64_sys_read+0x3e/0x50 fs/read_write.c:628
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x00000040 -> 0x00000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 20795 Comm: syz-executor.2 Not tainted 5.18.0-rc7-syzkaller-00164-g6c3f5bec9b40-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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