[PATCH v2 1/5] staging: most: dim2: replace BUG_ON() in try_start_dim_transfer()

From: grondon

Date: Mon Mar 30 2026 - 14:26:04 EST


From: Gabriel Rondon <grondon@xxxxxxxxx>

Replace BUG_ON() calls with graceful error handling.

For the null/uninitialized channel checks, return -EINVAL instead of
crashing the kernel. For the zero bus_address check, release the
spinlock and return -EFAULT.

BUG_ON() is deprecated as it crashes the entire kernel on assertion
failure (see Documentation/process/deprecated.rst).

Signed-off-by: Gabriel Rondon <grondon@xxxxxxxxx>
---
drivers/staging/most/dim2/dim2.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/staging/most/dim2/dim2.c b/drivers/staging/most/dim2/dim2.c
index 66617e89e..48315f8cd 100644
--- a/drivers/staging/most/dim2/dim2.c
+++ b/drivers/staging/most/dim2/dim2.c
@@ -165,8 +165,8 @@ static int try_start_dim_transfer(struct hdm_channel *hdm_ch)
unsigned long flags;
struct dim_ch_state st;

- BUG_ON(!hdm_ch);
- BUG_ON(!hdm_ch->is_initialized);
+ if (!hdm_ch || !hdm_ch->is_initialized)
+ return -EINVAL;

spin_lock_irqsave(&dim_lock, flags);
if (list_empty(head)) {
@@ -187,7 +187,10 @@ static int try_start_dim_transfer(struct hdm_channel *hdm_ch)
return -EAGAIN;
}

- BUG_ON(mbo->bus_address == 0);
+ if (mbo->bus_address == 0) {
+ spin_unlock_irqrestore(&dim_lock, flags);
+ return -EFAULT;
+ }
if (!dim_enqueue_buffer(&hdm_ch->ch, mbo->bus_address, buf_size)) {
list_del(head->next);
spin_unlock_irqrestore(&dim_lock, flags);
--
2.33.0