On Fri, Dec 15, 2023 at 02:51:09PM +0100, Johan Hovold wrote: > On Thu, Dec 14, 2023 at 06:01:46PM +0100, Francesco Dolcini wrote: > > From: Francesco Dolcini <francesco.dolcini@xxxxxxxxxxx> > > > > 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. > > > > Suggested-by: Jiri Slaby <jirislaby@xxxxxxxxxx> > > Link: https://lore.kernel.org/all/087be419-ec6b-47ad-851a-5e1e3ea5cfcc@xxxxxxxxxx/ > > Signed-off-by: Francesco Dolcini <francesco.dolcini@xxxxxxxxxxx> > > --- > > hello, > > patch is based on current linux next. > > > > It has an obvious problem, it touches files from multiple subsystem in a single > > patch that is complicated to review and eventually merge, just splitting this > > would however not work, it will break bisectability and the build. > > > > I am looking for advise on the best way to move forward. > > > > I see the following options: > > - keep it as it is > > - break it down with a patch with each subsystem, and squash before applying > > from a single (tty?) subsystem > > - go for a multi stage approach, defining a new callback, move to it and in > > the end remove the original one, likewise it was done for i2c lately > > > > --- > > drivers/bluetooth/btmtkuart.c | 4 ++-- > > drivers/bluetooth/btnxpuart.c | 4 ++-- > > > diff --git a/drivers/bluetooth/btmtkuart.c b/drivers/bluetooth/btmtkuart.c > > index 3c84fcbda01a..e6bc4a73c9fc 100644 > > --- a/drivers/bluetooth/btmtkuart.c > > +++ b/drivers/bluetooth/btmtkuart.c > > @@ -383,8 +383,8 @@ static void btmtkuart_recv(struct hci_dev *hdev, const u8 *data, size_t count) > > } > > } > > > > -static ssize_t btmtkuart_receive_buf(struct serdev_device *serdev, > > - const u8 *data, size_t count) > > +static size_t btmtkuart_receive_buf(struct serdev_device *serdev, > > + const u8 *data, size_t count) > > { > > struct btmtkuart_dev *bdev = serdev_device_get_drvdata(serdev); > > > > diff --git a/drivers/bluetooth/btnxpuart.c b/drivers/bluetooth/btnxpuart.c > > index 1d592ac413d1..056bef5b2919 100644 > > --- a/drivers/bluetooth/btnxpuart.c > > +++ b/drivers/bluetooth/btnxpuart.c > > @@ -1264,8 +1264,8 @@ static const struct h4_recv_pkt nxp_recv_pkts[] = { > > { NXP_RECV_FW_REQ_V3, .recv = nxp_recv_fw_req_v3 }, > > }; > > > > -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") > > > diff --git a/drivers/tty/serdev/serdev-ttyport.c b/drivers/tty/serdev/serdev-ttyport.c > > index e94e090cf0a1..3d7ae7fa5018 100644 > > --- a/drivers/tty/serdev/serdev-ttyport.c > > +++ b/drivers/tty/serdev/serdev-ttyport.c > > @@ -27,19 +27,17 @@ static size_t ttyport_receive_buf(struct tty_port *port, const u8 *cp, > > { > > struct serdev_controller *ctrl = port->client_data; > > struct serport *serport = serdev_controller_get_drvdata(ctrl); > > - int ret; > > + size_t ret; > > > > if (!test_bit(SERPORT_ACTIVE, &serport->flags)) > > return 0; > > > > ret = serdev_controller_receive_buf(ctrl, cp, count); > > > > - dev_WARN_ONCE(&ctrl->dev, ret < 0 || ret > count, > > - "receive_buf returns %d (count = %zu)\n", > > + dev_WARN_ONCE(&ctrl->dev, ret > count, > > + "receive_buf returns %zu (count = %zu)\n", > > ret, count); > > - if (ret < 0) > > - return 0; > > - else if (ret > count) > > + if (ret > count) > > return count; > > > > return ret; > > So please do not apply this patch until the various implementations have > been fixed. > > Johan
