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BUG: KCSAN: data-race in blk_mq_get_request / blk_mq_get_request

write to 0xffff8881299a3d48 of 8 bytes by task 7462 on cpu 0:
 blk_mq_get_request+0x91a/0xba0 block/blk-mq.c:396
 blk_mq_make_request+0x2d7/0xf60 block/blk-mq.c:2001
 generic_make_request block/blk-core.c:1075 [inline]
 generic_make_request+0x196/0x700 block/blk-core.c:1017
 submit_bio+0x8f/0x3a0 block/blk-core.c:1200
 blk_next_bio+0x4f/0x70 block/blk-lib.c:19
 __blkdev_issue_zero_pages+0x106/0x2f0 block/blk-lib.c:284
 blkdev_issue_zeroout+0x32d/0x360 block/blk-lib.c:378
 blk_ioctl_zeroout block/ioctl.c:270 [inline]
 blkdev_common_ioctl+0x44a/0xea0 block/ioctl.c:608
 blkdev_ioctl+0x130/0x420 block/ioctl.c:716
 block_ioctl+0x91/0xb0 fs/block_dev.c:1996
 vfs_ioctl fs/ioctl.c:47 [inline]
 ksys_ioctl+0x101/0x150 fs/ioctl.c:763
 __do_sys_ioctl fs/ioctl.c:772 [inline]
 __se_sys_ioctl fs/ioctl.c:770 [inline]
 __x64_sys_ioctl+0x47/0x60 fs/ioctl.c:770
 do_syscall_64+0xc7/0x3b0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff8881299a3d48 of 8 bytes by task 7472 on cpu 1:
 blk_mq_get_request+0x907/0xba0 block/blk-mq.c:396
 blk_mq_make_request+0x2d7/0xf60 block/blk-mq.c:2001
 generic_make_request block/blk-core.c:1075 [inline]
 generic_make_request+0x196/0x700 block/blk-core.c:1017
 submit_bio+0x8f/0x3a0 block/blk-core.c:1200
 blk_next_bio+0x4f/0x70 block/blk-lib.c:19
 __blkdev_issue_zero_pages+0x106/0x2f0 block/blk-lib.c:284
 blkdev_issue_zeroout+0x32d/0x360 block/blk-lib.c:378
 blk_ioctl_zeroout block/ioctl.c:270 [inline]
 blkdev_common_ioctl+0x44a/0xea0 block/ioctl.c:608
 blkdev_ioctl+0x130/0x420 block/ioctl.c:716
 block_ioctl+0x91/0xb0 fs/block_dev.c:1996
 vfs_ioctl fs/ioctl.c:47 [inline]
 ksys_ioctl+0x101/0x150 fs/ioctl.c:763
 __do_sys_ioctl fs/ioctl.c:772 [inline]
 __se_sys_ioctl fs/ioctl.c:770 [inline]
 __x64_sys_ioctl+0x47/0x60 fs/ioctl.c:770
 do_syscall_64+0xc7/0x3b0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 7472 Comm: syz-executor.4 Not tainted 5.7.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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