[BUG] KCSAN: data-race in process_one_work / process_one_work

From: Mirsad Todorovac
Date: Thu Aug 17 2023 - 15:25:39 EST


Hi,

This is your friendly bug reporter.

The environment is vanilla torvalds tree kernel on Ubuntu 22.04 LTS and on a Ryzen 7950X
assembled box.

The kernel reports G taint "properietary module loaded", but I know of no module since
the boot state when the status was "Not tainted".

Please find the complete dmesg output (or what's left in the ring buffer) and lshw output
attached.

Here is the dmesg output excerpt:

[ 6849.221584] ==================================================================
[ 6849.221607] BUG: KCSAN: data-race in process_one_work / process_one_work

[ 6849.221635] write to 0xffff9b7440151398 of 8 bytes by task 6364 on cpu 7:
[ 6849.221647] process_one_work+0x504/0x930
[ 6849.221660] worker_thread+0x311/0x7e0
[ 6849.221673] kthread+0x18b/0x1d0
[ 6849.221683] ret_from_fork+0x43/0x70
[ 6849.221695] ret_from_fork_asm+0x1b/0x30

[ 6849.221712] read to 0xffff9b7440151398 of 8 bytes by task 5586 on cpu 28:
[ 6849.221724] process_one_work+0x4e8/0x930
[ 6849.221737] worker_thread+0x519/0x7e0
[ 6849.221749] kthread+0x18b/0x1d0
[ 6849.221759] ret_from_fork+0x43/0x70
[ 6849.221770] ret_from_fork_asm+0x1b/0x30

[ 6849.221786] value changed: 0x00000000000154d0 -> 0x00000000000154d1

[ 6849.221802] Reported by Kernel Concurrency Sanitizer on:
[ 6849.221811] CPU: 28 PID: 5586 Comm: kworker/u64:0 Tainted: G L 6.5.0-rc6-net-cfg-kcsan-00038-g16931859a650 #35
[ 6849.221825] Hardware name: ASRock X670E PG Lightning/X670E PG Lightning, BIOS 1.21 04/26/2023
[ 6849.221833] Workqueue: events_unbound wq_barrier_func
[ 6849.221846] ==================================================================

Best regards,
Mirsad Todorovac

Attachment: dmesg-3.log.xz
Description: application/xz

Attachment: lshw.txt.xz
Description: application/xz