Re: [PATCH v1] treewide, serdev: change receive_buf() return type to size_t

On Fri, Dec 15, 2023 at 02:59:35PM +0100, Francesco Dolcini wrote:

On Fri, Dec 15, 2023 at 02:51:09PM +0100, Johan Hovold wrote:

quoted

On Thu, Dec 14, 2023 at 06:01:46PM +0100, Francesco Dolcini wrote:

quoted

From: Francesco Dolcini <redacted>

receive_buf() is called from ttyport_receive_buf() that expects values
">= 0" from serdev_controller_receive_buf(), change its return type from
ssize_t to size_t.

quoted

quoted

 drivers/bluetooth/btmtkuart.c              |  4 ++--
 drivers/bluetooth/btnxpuart.c              |  4 ++--

quoted

quoted

-static ssize_t btnxpuart_receive_buf(struct serdev_device *serdev,
-				     const u8 *data, size_t count)
+static size_t btnxpuart_receive_buf(struct serdev_device *serdev,
+				    const u8 *data, size_t count)
 {
 	struct btnxpuart_dev *nxpdev = serdev_device_get_drvdata(serdev);

A quick check of just the first two functions here shows that they can
return negative values.

This is already fixed. Patches are in next.

There were 3 buggy user of this API.
 - 1 patch was merged a few days ago in mainline
 - 2 patches are in next, the maintainer decided to wait for the next merge window

commit 687d2de93b11 ("Bluetooth: btmtkuart: fix recv_buf() return value")
commit 7954bbcdd7ea ("Bluetooth: btnxpuart: fix recv_buf() return value")
commit c8820c92caf0 ("platform/surface: aggregator: fix recv_buf() return value")

Then why was that not mentioned in the patch (e.g. below the --- line)?

You are certainly not making it easy for reviewers, but good to see that
you thought about this, and I see now when reviewing the mail archives
that those bugs were the reason for this patch in the first place.

Johan