linux-kernel - [PATCH] xen: drop writing error messages to xenstore

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Date:   Tue,  9 Oct 2018 18:09:59 +0200
From:   Juergen Gross <jgross@...e.com>
To:     linux-kernel@...r.kernel.org, xen-devel@...ts.xenproject.org
Cc:     boris.ostrovsky@...cle.com, Juergen Gross <jgross@...e.com>
Subject: [PATCH] xen: drop writing error messages to xenstore

xenbus_va_dev_error() will try to write error messages to Xenstore
under the error/<dev-name>/error node (with <dev-name> something like
"device/vbd/51872"). This will fail normally and another message
about this failure is added to dmesg.

I believe this is a remnant from very ancient times, as it was added
in the first pvops rush of commits in 2007.

So remove the additional message when writing to Xenstore failed as
a minimum step.

Signed-off-by: Juergen Gross <jgross@...e.com>
---
I am considering removing the Xenstore write altogether, but I'm
not sure it isn't needed e.g. by xend based installations. So please
speak up in case you know why this write is there.
---
 drivers/xen/xenbus/xenbus_client.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/xen/xenbus/xenbus_client.c b/drivers/xen/xenbus/xenbus_client.c
index a1c17000129b..e17ca8156171 100644
--- a/drivers/xen/xenbus/xenbus_client.c
+++ b/drivers/xen/xenbus/xenbus_client.c
@@ -278,10 +278,8 @@ static void xenbus_va_dev_error(struct xenbus_device *dev, int err,
 	dev_err(&dev->dev, "%s\n", printf_buffer);
 
 	path_buffer = kasprintf(GFP_KERNEL, "error/%s", dev->nodename);
-	if (!path_buffer ||
-	    xenbus_write(XBT_NIL, path_buffer, "error", printf_buffer))
-		dev_err(&dev->dev, "failed to write error node for %s (%s)\n",
-			dev->nodename, printf_buffer);
+	if (path_buffer)
+		xenbus_write(XBT_NIL, path_buffer, "error", printf_buffer);
 
 	kfree(printf_buffer);
 	kfree(path_buffer);
-- 
2.16.4