Thx Greg,
Pls ignore this thread. Already correct to the normal linux-kernel@vger.kernel.org in another email thread.
Thx and BRs, Aiqun Yu (Maria)
-----Original Message----- From: Greg KH gregkh@linuxfoundation.org Sent: Thursday, October 27, 2022 3:24 PM To: Aiqun Yu (QUIC) quic_aiquny@quicinc.com Cc: linus.walleij@linaro.org; linux-gpio@vger.kernel.org; stable@vger.kernel.org Subject: Re: [PATCH] pinctrl: core: Make p->state in order in pinctrl_commit_state
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On Thu, Oct 27, 2022 at 02:51:10PM +0800, Maria Yu wrote:
We've got a dump that current cpu is in pinctrl_commit_state, the old_state != p->state while the stack is still in the process of pinmux_disable_setting. So it means even if the current p->state is changed in new state, the settings are not yet up-to-date enabled complete yet.
Currently p->state in different value to synchronize the pinctrl_commit_state behaviors. The p->state will have transaction like old_state -> NULL -> new_state. When in old_state, it will try to disable all the all state settings. And when after new state settings enabled, p->state will changed to the new state after that. So use smp_mb to synchronize the p->state variable and the settings in order.
drivers/pinctrl/core.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/drivers/pinctrl/core.c b/drivers/pinctrl/core.c index 9e57f4c62e60..cd917a5b1a0a 100644 --- a/drivers/pinctrl/core.c +++ b/drivers/pinctrl/core.c @@ -1256,6 +1256,7 @@ static int pinctrl_commit_state(struct pinctrl *p, struct pinctrl_state *state) } }
smp_mb(); p->state = NULL; /* Apply all the settings for the new state - pinmux first */ @@-1305,6 +1306,7 @@ static int pinctrl_commit_state(struct pinctrl *p, struct pinctrl_state *state) pinctrl_link_add(setting->pctldev, p->dev); }
smp_mb(); p->state = state; return 0;-- 2.17.1
<formletter>
This is not the correct way to submit patches for inclusion in the stable kernel tree. Please read: https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html for how to do this properly.
</formletter>