Re: [syzbot] [media?] INFO: task hung in cec_claim_log_addrs

From: Edward Adam Davis
Date: Wed Feb 21 2024 - 08:20:28 EST


please test hung in cec_claim_log_addrs

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master

diff --git a/drivers/media/cec/core/cec-adap.c b/drivers/media/cec/core/cec-adap.c
index 5741adf09a2e..21b3ff504524 100644
--- a/drivers/media/cec/core/cec-adap.c
+++ b/drivers/media/cec/core/cec-adap.c
@@ -1436,7 +1436,6 @@ static int cec_config_thread_func(void *arg)
int err;
int i, j;

- mutex_lock(&adap->lock);
dprintk(1, "physical address: %x.%x.%x.%x, claim %d logical addresses\n",
cec_phys_addr_exp(adap->phys_addr), las->num_log_addrs);
las->log_addr_mask = 0;
@@ -1565,7 +1564,6 @@ static int cec_config_thread_func(void *arg)
}
adap->kthread_config = NULL;
complete(&adap->config_completion);
- mutex_unlock(&adap->lock);
call_void_op(adap, configured);
return 0;

@@ -1577,7 +1575,6 @@ static int cec_config_thread_func(void *arg)
adap->must_reconfigure = false;
adap->kthread_config = NULL;
complete(&adap->config_completion);
- mutex_unlock(&adap->lock);
return 0;
}

@@ -1602,9 +1599,7 @@ static void cec_claim_log_addrs(struct cec_adapter *adap, bool block)
adap->kthread_config = NULL;
adap->is_configuring = false;
} else if (block) {
- mutex_unlock(&adap->lock);
wait_for_completion(&adap->config_completion);
- mutex_lock(&adap->lock);
}
}