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Loic Poulain
d50a9b7fd0
[ Upstream commit1ca52c0983] Enabling runtime PM before attaching the QPHY instance as driver data can lead to a NULL pointer dereference in runtime PM callbacks that expect valid driver data. There is a small window where the suspend callback may run after PM runtime enabling and before runtime forbid. This causes a sporadic crash during boot: ``` Unable to handle kernel NULL pointer dereference at virtual address 00000000000000a1 [...] CPU: 0 UID: 0 PID: 11 Comm: kworker/0:1 Not tainted 6.16.7+ #116 PREEMPT Workqueue: pm pm_runtime_work pstate: 20000005 (nzCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : qusb2_phy_runtime_suspend+0x14/0x1e0 [phy_qcom_qusb2] lr : pm_generic_runtime_suspend+0x2c/0x44 [...] ``` Attach the QPHY instance as driver data before enabling runtime PM to prevent NULL pointer dereference in runtime PM callbacks. Reorder pm_runtime_enable() and pm_runtime_forbid() to prevent a short window where an unnecessary runtime suspend can occur. Use the devres-managed version to ensure PM runtime is symmetrically disabled during driver removal for proper cleanup. Fixes:891a96f65a("phy: qcom-qusb2: Add support for runtime PM") Signed-off-by: Loic Poulain <loic.poulain@oss.qualcomm.com> Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com> Reviewed-by: Abel Vesa <abel.vesa@oss.qualcomm.com> Link: https://patch.msgid.link/20251219085640.114473-1-loic.poulain@oss.qualcomm.com Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>