loop0: p2 p3 p4
loop0: p2 size 327680 extends beyond EOD, truncated
loop0: p3 size 3053649920 extends beyond EOD, 
==================================================================
BUG: KCSAN: data-race in data_alloc / data_push_tail

write to 0xffffffff86da5c78 of 8 bytes by task 26816 on cpu 0:
 data_alloc+0x205/0x2b0 kernel/printk/printk_ringbuffer.c:1071
 prb_reserve+0x920/0xbf0 kernel/printk/printk_ringbuffer.c:1549
 vprintk_store+0x560/0xbb0 kernel/printk/printk.c:2176
 vprintk_emit+0xac/0x3c0 kernel/printk/printk.c:2229
 vprintk_default+0x22/0x30 kernel/printk/printk.c:2256
 vprintk+0x7f/0x90 kernel/printk/printk_safe.c:50
 _printk+0x76/0x97 kernel/printk/printk.c:2266
 check_partition block/partitions/core.c:160 [inline]
 blk_add_partitions block/partitions/core.c:609 [inline]
 bdev_disk_changed+0x984/0xc20 block/partitions/core.c:695
 loop_reread_partitions drivers/block/loop.c:518 [inline]
 loop_set_status+0x533/0x5d0 drivers/block/loop.c:1305
 lo_ioctl+0x835/0x1260
 blkdev_ioctl+0x20e/0x440 block/ioctl.c:588
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0xcb/0x140 fs/ioctl.c:860
 __x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffffffff86da5c78 of 8 bytes by task 26811 on cpu 1:
 data_make_reusable kernel/printk/printk_ringbuffer.c:587 [inline]
 data_push_tail+0x138/0x470 kernel/printk/printk_ringbuffer.c:672
 data_alloc+0xbc/0x2b0 kernel/printk/printk_ringbuffer.c:1043
 prb_reserve+0x920/0xbf0 kernel/printk/printk_ringbuffer.c:1549
 vprintk_store+0x560/0xbb0 kernel/printk/printk.c:2176
 vprintk_emit+0xac/0x3c0 kernel/printk/printk.c:2229
 vprintk_default+0x22/0x30 kernel/printk/printk.c:2256
 vprintk+0x7f/0x90 kernel/printk/printk_safe.c:50
 _printk+0x76/0x97 kernel/printk/printk.c:2266
 blk_add_partition block/partitions/core.c:571 [inline]
 blk_add_partitions block/partitions/core.c:653 [inline]
 bdev_disk_changed+0x843/0xc20 block/partitions/core.c:695
 loop_reread_partitions drivers/block/loop.c:518 [inline]
 loop_set_status+0x533/0x5d0 drivers/block/loop.c:1305
 lo_ioctl+0x835/0x1260
 blkdev_ioctl+0x20e/0x440 block/ioctl.c:588
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0xcb/0x140 fs/ioctl.c:860
 __x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x000000010005466d -> 0x00000001000559a1

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 26811 Comm: syz-executor.0 Not tainted 5.17.0-rc7-syzkaller-00020-gea4424be1688-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================
truncated
loop0: p4 size 2097152 extends beyond EOD, 
truncated