2022-11-11 03:04:48

by Huisong Li

[permalink] [raw]
Subject: [PATCH V2 2/2] mailbox: pcc: fix 'pcc_chan_count' when fail to initialize PCC

Currently, 'pcc_chan_count' is a non-zero value if PCC subspaces are parsed
successfully and subsequent processes is failure during initializing PCC
process. This may cause that pcc_mbox_request_channel() can still be
executed successfully , which will misleads the caller that this channel is
available.

Fixes: ce028702ddbc ("mailbox: pcc: Move bulk of PCCT parsing into pcc_mbox_probe")
Signed-off-by: Huisong Li <[email protected]>
---
drivers/mailbox/pcc.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/mailbox/pcc.c b/drivers/mailbox/pcc.c
index 3c2bc0ca454c..105d46c9801b 100644
--- a/drivers/mailbox/pcc.c
+++ b/drivers/mailbox/pcc.c
@@ -743,6 +743,7 @@ static int __init pcc_init(void)

if (IS_ERR(pcc_pdev)) {
pr_debug("Err creating PCC platform bundle\n");
+ pcc_chan_count = 0;
return PTR_ERR(pcc_pdev);
}

--
2.22.0



2022-11-11 16:33:07

by Sudeep Holla

[permalink] [raw]
Subject: Re: [PATCH V2 2/2] mailbox: pcc: fix 'pcc_chan_count' when fail to initialize PCC

Change $subject as
"mailbox: pcc: Reset pcc_chan_count to zero in case of PCC probe failure"

On Fri, Nov 11, 2022 at 10:44:48AM +0800, Huisong Li wrote:
> Currently, 'pcc_chan_count' is a non-zero value if PCC subspaces are parsed
> successfully and subsequent processes is failure during initializing PCC
> process. This may cause that pcc_mbox_request_channel() can still be
> executed successfully , which will misleads the caller that this channel is
> available.
>

I would reword this something like:
"Currently, 'pcc_chan_count' is remains set to a non-zero value if PCC
subspaces are parsed successfully but something else fail later during
the initial PCC probing phase. This will result in pcc_mbox_request_channel()
trying to access the resources that are not initialised or allocated and
may end up in a system crash.

Reset pcc_chan_count to 0 when the PCC probe fails in order to prevent
the possible issue as described above.
"

> Fixes: ce028702ddbc ("mailbox: pcc: Move bulk of PCCT parsing into pcc_mbox_probe")

Other than that,

Reviewed-by: Sudeep Holla <[email protected]>

--
Regards,
Sudeep