diff mbox series

PM / suspend: Abort suspend if somebody holds wakelock

Message ID 1633537640-15800-1-git-send-email-mojha@codeaurora.org (mailing list archive)
State Rejected, archived
Headers show
Series PM / suspend: Abort suspend if somebody holds wakelock | expand

Commit Message

Mukesh Ojha Oct. 6, 2021, 4:27 p.m. UTC
There could be a scenario, where request_firmware() call results in
user land process trying to load firmwares into memory and
parallely one miscellaneous process is trying to invoke manual
suspend and due to which user mode helper gets disabled during
freezing of processes and that aborts loading of firmware even
though request_firmware() thread has taken wakelock.

Although, we are checking for any wakeup event inside
try_to_freeze_tasks() but that could be too late for the
above scenario.

Let's add a check before freezing/disable user land process in
suspend path.

Signed-off-by: Mukesh Ojha <mojha@codeaurora.org>
---
 kernel/power/process.c | 3 +++
 1 file changed, 3 insertions(+)

Comments

Rafael J. Wysocki Oct. 6, 2021, 4:33 p.m. UTC | #1
On Wed, Oct 6, 2021 at 6:27 PM Mukesh Ojha <mojha@codeaurora.org> wrote:
>
> There could be a scenario, where request_firmware() call results in
> user land process trying to load firmwares into memory and
> parallely one miscellaneous process is trying to invoke manual
> suspend and due to which user mode helper gets disabled during
> freezing of processes and that aborts loading of firmware even
> though request_firmware() thread has taken wakelock.
>
> Although, we are checking for any wakeup event inside
> try_to_freeze_tasks() but that could be too late for the
> above scenario.
>
> Let's add a check before freezing/disable user land process in
> suspend path.

If a laptop lid is closed and the system is expected to suspend, it
must suspend.

This takes precedence over the loading of firmware.  Sorry.

> Signed-off-by: Mukesh Ojha <mojha@codeaurora.org>
> ---
>  kernel/power/process.c | 3 +++
>  1 file changed, 3 insertions(+)
>
> diff --git a/kernel/power/process.c b/kernel/power/process.c
> index 37401c9..3e0d3d6 100644
> --- a/kernel/power/process.c
> +++ b/kernel/power/process.c
> @@ -124,6 +124,9 @@ int freeze_processes(void)
>  {
>         int error;
>
> +       if (pm_wakeup_pending())
> +               return -EBUSY;
> +
>         error = __usermodehelper_disable(UMH_FREEZING);
>         if (error)
>                 return error;
> --
> Qualcomm India Private Limited, on behalf of Qualcomm Innovation Center,
> Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project
>
diff mbox series

Patch

diff --git a/kernel/power/process.c b/kernel/power/process.c
index 37401c9..3e0d3d6 100644
--- a/kernel/power/process.c
+++ b/kernel/power/process.c
@@ -124,6 +124,9 @@  int freeze_processes(void)
 {
 	int error;
 
+	if (pm_wakeup_pending())
+		return -EBUSY;
+
 	error = __usermodehelper_disable(UMH_FREEZING);
 	if (error)
 		return error;