On Mon, 19 Aug 2024 at 04:47, Bjorn Andersson <quic_bjorande@xxxxxxxxxxx> wrote: > > Amit and Johan both reported a NULL pointer dereference in the > pmic_glink client code during initialization, and Stephen Boyd pointed > out the problem (race condition). > > While investigating, and writing the fix, I noticed that > ucsi_unregister() is called in atomic context but tries to sleep, and I > also noticed that the condition for when to inform the pmic_glink client > drivers when the remote has gone down is just wrong. > > So, let's fix all three. > > As mentioned in the commit message for the UCSI fix, I have a series in > the works that makes the GLINK callback happen in a sleepable context, > which would remove the need for the clients list to be protected by a > spinlock, and removing the work scheduling. This is however not -rc > material... > > In addition to the NULL pointer dereference, there is the -ECANCELED > issue reported here: > https://lore.kernel.org/all/Zqet8iInnDhnxkT9@xxxxxxxxxxxxxxxxxxxx/ > I have not yet been able to either reproduce this or convince myself > that this is the same issue. > Thank you for the fixes Bjorn. I'm not able to reproduce that pmic_glink kernel panic on SM8550-HDK anymore. Tested-by: Amit Pundir <amit.pundir@xxxxxxxxxx> > Signed-off-by: Bjorn Andersson <quic_bjorande@xxxxxxxxxxx> > --- > Bjorn Andersson (3): > soc: qcom: pmic_glink: Fix race during initialization > usb: typec: ucsi: Move unregister out of atomic section > soc: qcom: pmic_glink: Actually communicate with remote goes down > > drivers/power/supply/qcom_battmgr.c | 16 ++++++++----- > drivers/soc/qcom/pmic_glink.c | 40 +++++++++++++++++++++---------- > drivers/soc/qcom/pmic_glink_altmode.c | 17 +++++++++----- > drivers/usb/typec/ucsi/ucsi_glink.c | 44 ++++++++++++++++++++++++++--------- > include/linux/soc/qcom/pmic_glink.h | 11 +++++---- > 5 files changed, 88 insertions(+), 40 deletions(-) > --- > base-commit: 296c871d2904cff2b4742702ef94512ab467a8e3 > change-id: 20240818-pmic-glink-v6-11-races-363f5964c339 > > Best regards, > -- > Bjorn Andersson <quic_bjorande@xxxxxxxxxxx> >
