lkml.org 
[lkml]   [2020]   [Feb]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH] platform/chrome: cros_ec_rpmsg: Fix race with host event.
From
Date
Hi Pi-Hsun,

On 14/2/20 9:26, Pi-Hsun Shih wrote:
> Host event can be sent by remoteproc by any time, and
> cros_ec_rpmsg_callback would be called after cros_ec_rpmsg_create_ept.
> But the cros_ec_device is initialized after that, which cause host event
> handler to use cros_ec_device that are not initialized properly yet.
>

I don't have the hardware to test but, can't we call first cros_ec_register and
then cros_ec_rpmsg_create_ept?

Start receiving driver callbacks before finishing to probe the drivers itself
sounds weird to me.

Thanks,
Enric

> Fix this by don't schedule host event handler before cros_ec_register
> returns. Instead, remember that we have a pending host event, and
> schedule host event handler after cros_ec_register.
>
> Fixes: 71cddb7097e2 ("platform/chrome: cros_ec_rpmsg: Fix race with host command when probe failed.")
> Signed-off-by: Pi-Hsun Shih <pihsun@chromium.org>
> ---
> drivers/platform/chrome/cros_ec_rpmsg.c | 16 +++++++++++++++-
> 1 file changed, 15 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/platform/chrome/cros_ec_rpmsg.c b/drivers/platform/chrome/cros_ec_rpmsg.c
> index dbc3f5523b83..7e8629e3db74 100644
> --- a/drivers/platform/chrome/cros_ec_rpmsg.c
> +++ b/drivers/platform/chrome/cros_ec_rpmsg.c
> @@ -44,6 +44,8 @@ struct cros_ec_rpmsg {
> struct completion xfer_ack;
> struct work_struct host_event_work;
> struct rpmsg_endpoint *ept;
> + bool has_pending_host_event;
> + bool probe_done;
> };
>
> /**
> @@ -177,7 +179,14 @@ static int cros_ec_rpmsg_callback(struct rpmsg_device *rpdev, void *data,
> memcpy(ec_dev->din, resp->data, len);
> complete(&ec_rpmsg->xfer_ack);
> } else if (resp->type == HOST_EVENT_MARK) {
> - schedule_work(&ec_rpmsg->host_event_work);
> + /*
> + * If the host event is sent before cros_ec_register is
> + * finished, queue the host event.
> + */
> + if (ec_rpmsg->probe_done)
> + schedule_work(&ec_rpmsg->host_event_work);
> + else
> + ec_rpmsg->has_pending_host_event = true;
> } else {
> dev_warn(ec_dev->dev, "rpmsg received invalid type = %d",
> resp->type);
> @@ -240,6 +249,11 @@ static int cros_ec_rpmsg_probe(struct rpmsg_device *rpdev)
> return ret;
> }
>
> + ec_rpmsg->probe_done = true;
> +
> + if (ec_rpmsg->has_pending_host_event)
> + schedule_work(&ec_rpmsg->host_event_work);
> +
> return 0;
> }
>
>
> base-commit: b19e8c68470385dd2c5440876591fddb02c8c402
>

\
 
 \ /
  Last update: 2020-02-14 16:10    [W:1.812 / U:0.008 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site