| Message ID | 20250327150406.138736-1-senozhatsky@chromium.org (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [PATCHv3] thunderbolt: do not double dequeue a request | expand |
diff --git a/drivers/thunderbolt/ctl.c b/drivers/thunderbolt/ctl.c index cd15e84c47f4..1db2e951b53f 100644 --- a/drivers/thunderbolt/ctl.c +++ b/drivers/thunderbolt/ctl.c @@ -151,6 +151,11 @@ static void tb_cfg_request_dequeue(struct tb_cfg_request *req) struct tb_ctl *ctl = req->ctl; mutex_lock(&ctl->request_queue_lock); + if (!test_bit(TB_CFG_REQUEST_ACTIVE, &req->flags)) { + mutex_unlock(&ctl->request_queue_lock); + return; + } + list_del(&req->list); clear_bit(TB_CFG_REQUEST_ACTIVE, &req->flags); if (test_bit(TB_CFG_REQUEST_CANCELED, &req->flags))
Some of our devices crash in tb_cfg_request_dequeue(): general protection fault, probably for non-canonical address 0xdead000000000122 CPU: 6 PID: 91007 Comm: kworker/6:2 Tainted: G U W 6.6.65 RIP: 0010:tb_cfg_request_dequeue+0x2d/0xa0 Call Trace: <TASK> ? tb_cfg_request_dequeue+0x2d/0xa0 tb_cfg_request_work+0x33/0x80 worker_thread+0x386/0x8f0 kthread+0xed/0x110 ret_from_fork+0x38/0x50 ret_from_fork_asm+0x1b/0x30 The circumstances are unclear, however, the theory is that tb_cfg_request_work() can be scheduled twice for a request: first time via frame.callback from ring_work() and second time from tb_cfg_request(). Both times kworkers will execute tb_cfg_request_dequeue(), which results in double list_del() from the ctl->request_queue (the list poison deference hints at it: 0xdead000000000122). Do not dequeue requests that don't have TB_CFG_REQUEST_ACTIVE bit set. Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: stable@vger.kernel.org --- v3: tweaked commit message drivers/thunderbolt/ctl.c | 5 +++++ 1 file changed, 5 insertions(+)