On Mon, Jul 28, 2025 at 06:07:22AM +0200, Greg KH wrote:

On Mon, Jul 28, 2025 at 07:14:25AM +0530, Akhilesh Patil wrote:

quoted

Replace BUG() with WARN_ON() as recommended in
Documentation/process/deprecated.rst
Fix system entering into unstable/break/undebuggable state due to use
of BUG(). Follow strict suggestions as per [1] [2].

Link: https://lore.kernel.org/lkml/CA+55aFy6jNLsywVYdGp83AMrXBo_P-pkjkphPGrO=82SPKCpLQ@mail.gmail.com/ (local) [1]
Link: https://lore.kernel.org/lkml/CAHk-=whDHsbK3HTOpTF=ue_o04onRwTEaK_ZoJp_fjbqq4+=Jw@mail.gmail.com/ (local) [2]
Signed-off-by: Akhilesh Patil <akhilesh@ee.iitb.ac.in>
---
 drivers/tty/serial/ucc_uart.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/tty/serial/ucc_uart.c b/drivers/tty/serial/ucc_uart.c
index 0613f8c11ab1..6214ab1b67cb 100644
--- a/drivers/tty/serial/ucc_uart.c
+++ b/drivers/tty/serial/ucc_uart.c

@@ -223,7 +223,7 @@ static inline dma_addr_t cpu2qe_addr(void *addr, struct uart_qe_port *qe_port)
 
 	/* something nasty happened */
 	printk(KERN_ERR "%s: addr=%p\n", __func__, addr);
-	BUG();
+	WARN_ON(1);
 	return 0;
 }
 

@@ -242,7 +242,7 @@ static inline void *qe2cpu_addr(dma_addr_t addr, struct uart_qe_port *qe_port)
 
 	/* something nasty happened */
 	printk(KERN_ERR "%s: addr=%llx\n", __func__, (u64)addr);
-	BUG();
+	WARN_ON(1);
 	return NULL;
 }

You can't just do a search/replace for these types of things, otherwise
we would have done so a long time ago.

Hi greg, Agree. Let me dive deep to understand this BUG() -> WARN()
recommendation and come back after detailed analysis for this change.

How did you test this patch?  The BUG() here assumes that if this ever

I have done only build check with NXP p1025rdb configuration as I do not
have this particular hardware handy.

fires, the system is really broken, how have you recovered from that
broken state?

thanks,

greg k-h

Thanks for the review :) 

Regards,
Akhilesh