KCSAN: data-race in __kernel_write_iter / set_task

Kernel	Title	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
upstream	KCSAN: data-race in __kernel_write_iter / set_task_ioprio block				7	82d	222d	0/28	auto-obsoleted due to no activity on 2025/05/06 16:02

==================================================================
BUG: KCSAN: data-race in __kernel_write_iter / set_task_ioprio

write to 0xffff8881009d6a48 of 8 bytes by task 4808 on cpu 0:
 set_task_ioprio+0x24f/0x270 block/blk-ioc.c:280
 __do_sys_ioprio_set block/ioprio.c:121 [inline]
 __se_sys_ioprio_set+0x250/0x5a0 block/ioprio.c:65
 __x64_sys_ioprio_set+0x43/0x50 block/ioprio.c:65
 x64_sys_call+0x1982/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:252
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff8881009d6a48 of 8 bytes by task 4779 on cpu 1:
 __get_task_ioprio include/linux/ioprio.h:59 [inline]
 get_current_ioprio include/linux/ioprio.h:83 [inline]
 init_sync_kiocb include/linux/fs.h:2441 [inline]
 __kernel_write_iter+0xdc/0x4c0 fs/read_write.c:617
 dump_emit_page fs/coredump.c:1112 [inline]
 dump_user_range+0x407/0x8c0 fs/coredump.c:1186
 elf_core_dump+0x1dc2/0x1f80 fs/binfmt_elf.c:2075
 do_coredump+0x1dfd/0x27b0 fs/coredump.c:950
 get_signal+0xd85/0xf70 kernel/signal.c:3019
 arch_do_signal_or_restart+0x96/0x480 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
 irqentry_exit_to_user_mode+0x5e/0xa0 kernel/entry/common.c:184
 irqentry_exit+0x12/0x50 kernel/entry/common.c:287
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623

value changed: 0x0000000000000000 -> 0xffff8881016dc660

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 4779 Comm: +}[@ Not tainted 6.15.0-syzkaller-09113-g8477ab143069 #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
==================================================================