I think kernel 6.11.8 damaged my monitor's panel

Hi, I think the latest kernel update on CachyOS has damaged my monitor’s panel. During installation (using kernel 6.11.7), everything worked fine. But after installing and booting into kernel 6.11.8, the display panel stopped working completely.

I suspect the issue might be related to connecting an external monitor via Thunderbolt on my Intel laptop. Now, the panel doesn’t even show the splash screen. Has anyone else faced this problem?

I think these commits may be to blame:

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/diff/drivers/thunderbolt?id=v6.12-rc7&id2=v6.12-rc6

diff --git a/drivers/thunderbolt/usb4.c b/drivers/thunderbolt/usb4.c
index 0a9b4aeb3fa140..402fdf8b1cdeca 100644
--- a/drivers/thunderbolt/usb4.c
+++ b/drivers/thunderbolt/usb4.c
@@ -48,7 +48,7 @@ enum usb4_ba_index {
 
 /* Delays in us used with usb4_port_wait_for_bit() */
 #define USB4_PORT_DELAY			50
-#define USB4_PORT_SB_DELAY		5000
+#define USB4_PORT_SB_DELAY		1000

And

diff --git a/drivers/thunderbolt/retimer.c b/drivers/thunderbolt/retimer.c
index 7db9869a9f3fe7..89d2919d0193e8 100644
--- a/drivers/thunderbolt/retimer.c
+++ b/drivers/thunderbolt/retimer.c
@@ -532,6 +532,8 @@ int tb_retimer_scan(struct tb_port *port, bool add)
 	}
 
 	ret = 0;
+	if (!IS_ENABLED(CONFIG_USB4_DEBUGFS_MARGINING))
+		max = min(last_idx, max);
 
 	/* Add retimers if they do not exist already */
 	for (i = 1; i <= max; i++) {

Info:
Laptop:
CPU: 12th Gen Intel(R) Core™ i5-12450H (12) @ 4.40 GHz
GPU: Intel UHD Graphics @ 1.20 GHz [Integrated]
Laptop: Aspire A515-57 (V1.27)
OS: CachyOS latest version
Kernel: Linux 6.11.8

Monitor:
Brand: Pichau
Model: PG-CTR-BL01
Display size: 27"
Resolution: QHD - 2560x1440
Aspect ratio: 16:9
Backlight type: LED
Panel type: IPS
Response time: 1ms
Refresh rate: 165Hz
Pixels per inch (PPI): 108.78
Contrast ratio: 1000:1

If you think that’s the cause, can you revert and confirm?

1 Like

Hello, I figured out the issue. Initially, I thought the monitor was mistakenly identified as a Thunderbolt dock, causing it to receive too much voltage. However, I now believe the problem was due to the increase in the polling rate, which may have caused the panel to bug out. To fix it, I unplugged the monitor for 4 hours, connected an HDMI device, and then powered it back on while performing a reset. This resolved the issue.
Thank you for your attention.