On 2/7/2024 6:51 PM, Linus Walleij wrote:
On Fri, Feb 2, 2024 at 11:59 AM Maria Yu <quic_aiquny@xxxxxxxxxxx> wrote:
Currently pinctrl_select_state is an export symbol and don't have
effective re-entrance protect design. During async probing of devices
it's possible to end up in pinctrl_select_state() from multiple
contexts simultaneously, so make it thread safe.
More over, when the real racy happened, the system frequently have
printk message like:
"not freeing pin xx (xxx) as part of deactivating group xxx - it is
already used for some other setting".
Finally the system crashed after the flood log.
Add per pinctrl lock to ensure the old state and new state transition
atomization.
Also move dev error print message outside the region with interrupts
disabled.
Use scoped guard to simplify the lock protection needed code.
Fixes: 4198a9b57106 ("pinctrl: avoid reload of p state in list iteration")
Signed-off-by: Maria Yu <quic_aiquny@xxxxxxxxxxx>
Thank you for rebasing!
Patch applied now, so we get some shakeout in linux-next and can
make sure it works for everyone.
Feel free to add me into any thread related. Also I will try to pay
attention from the email list.
:)
Yours,
Linus Walleij
--
Thx and BRs,
Aiqun(Maria) Yu
