KCSAN: data-race in p9_conn_cancel / p9_read

Kernel	Title	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
upstream	KCSAN: data-race in p9_conn_cancel / p9_read_work (2) v9fs				1	118d	118d	0/28	auto-obsoleted due to no activity on 2024/07/13 05:58
upstream	KCSAN: data-race in p9_conn_cancel / p9_read_work v9fs				1	201d	201d	0/28	auto-obsoleted due to no activity on 2024/04/21 04:20

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BUG: KCSAN: data-race in p9_conn_cancel / p9_read_work

write to 0xffff888115642028 of 4 bytes by task 24 on cpu 1:
 p9_conn_cancel+0x89/0x400 net/9p/trans_fd.c:199
 p9_write_work+0x3ac/0x750 net/9p/trans_fd.c:522
 process_one_work kernel/workqueue.c:3231 [inline]
 process_scheduled_works+0x483/0x9a0 kernel/workqueue.c:3312
 worker_thread+0x526/0x6e0 kernel/workqueue.c:3389
 kthread+0x1d1/0x210 kernel/kthread.c:389
 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

read to 0xffff888115642028 of 4 bytes by task 3335 on cpu 0:
 p9_read_work+0x34/0x8d0 net/9p/trans_fd.c:286
 process_one_work kernel/workqueue.c:3231 [inline]
 process_scheduled_works+0x483/0x9a0 kernel/workqueue.c:3312
 worker_thread+0x526/0x6e0 kernel/workqueue.c:3389
 kthread+0x1d1/0x210 kernel/kthread.c:389
 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

value changed: 0x00000000 -> 0xffffff91

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 3335 Comm: kworker/0:3 Not tainted 6.11.0-rc5-syzkaller-00015-g3e9bff3bbe13 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Workqueue: events p9_read_work
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