==================================================================
BUG: KCSAN: data-race in copyin / copyin

write to 0xffff8881017bb000 of 4096 bytes by task 6857 on cpu 0:
 instrument_copy_from_user include/linux/instrumented.h:106 [inline]
 copyin+0x9e/0xb0 lib/iov_iter.c:151
 copy_page_from_iter_iovec lib/iov_iter.c:296 [inline]
 copy_page_from_iter+0x250/0x600 lib/iov_iter.c:942
 process_vm_rw_pages mm/process_vm_access.c:46 [inline]
 process_vm_rw_single_vec mm/process_vm_access.c:120 [inline]
 process_vm_rw_core.isra.0+0x3f1/0x760 mm/process_vm_access.c:218
 process_vm_rw+0x1c4/0x1e0 mm/process_vm_access.c:286
 __do_sys_process_vm_writev mm/process_vm_access.c:308 [inline]
 __se_sys_process_vm_writev mm/process_vm_access.c:303 [inline]
 __x64_sys_process_vm_writev+0x80/0xa0 mm/process_vm_access.c:303
 do_syscall_64+0xc7/0x390 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

write to 0xffff8881017bb000 of 4096 bytes by task 6860 on cpu 1:
 instrument_copy_from_user include/linux/instrumented.h:106 [inline]
 copyin+0x9e/0xb0 lib/iov_iter.c:151
 copy_page_from_iter_iovec lib/iov_iter.c:296 [inline]
 copy_page_from_iter+0x250/0x600 lib/iov_iter.c:942
 process_vm_rw_pages mm/process_vm_access.c:46 [inline]
 process_vm_rw_single_vec mm/process_vm_access.c:120 [inline]
 process_vm_rw_core.isra.0+0x3f1/0x760 mm/process_vm_access.c:218
 process_vm_rw+0x1c4/0x1e0 mm/process_vm_access.c:286
 __do_sys_process_vm_writev mm/process_vm_access.c:308 [inline]
 __se_sys_process_vm_writev mm/process_vm_access.c:303 [inline]
 __x64_sys_process_vm_writev+0x80/0xa0 mm/process_vm_access.c:303
 do_syscall_64+0xc7/0x390 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 6860 Comm: syz-executor.2 Not tainted 5.6.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================