From: Michael Kelley <mikelley@microsoft.com>
Date: Tue, 20 Apr 2021 08:44:19 -0700
Patch-mainline: v5.13-rc1
Subject: video: hyperv_fb: Add ratelimit on error message
Git-commit: aa5b7d11c7cb87c266d705b237368985e7171958
References: bsc#1185724
Due to a full ring buffer, the driver may be unable to send updates to
the Hyper-V host. But outputing the error message can make the problem
worse because console output is also typically written to the frame
buffer. As a result, in some circumstances the error message is output
continuously.
Break the cycle by rate limiting the error message. Also output
the error code for additional diagnosability.
Signed-off-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/1618933459-10585-1-git-send-email-mikelley@microsoft.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Acked-by: Olaf Hering <ohering@suse.de>
---
drivers/video/fbdev/hyperv_fb.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/video/fbdev/hyperv_fb.c b/drivers/video/fbdev/hyperv_fb.c
--- a/drivers/video/fbdev/hyperv_fb.c
+++ b/drivers/video/fbdev/hyperv_fb.c
@@ -308,7 +308,7 @@ static inline int synthvid_send(struct hv_device *hdev,
VM_PKT_DATA_INBAND, 0);
if (ret)
- pr_err("Unable to send packet via vmbus\n");
+ pr_err_ratelimited("Unable to send packet via vmbus; error %d\n", ret);
return ret;
}