Linux Kernel AXP717 Regulator Ramp Delay Vulnerability

A vulnerability in the Linux kernel's handling of the AXP717 regulator's ramp delay has been addressed. The issue arose because the AXP717 datasheet specifies a ramp delay of 15.625 microseconds per step, equivalent to 10mV in this context. The vulnerability was related to improper management of the ramp delay, particularly for DCDC4, where the steps should be 100mV. This mismanagement could lead to crashes when using CPU Dynamic Voltage and Frequency Scaling (DVFS). The vulnerability has been resolved by adding specific macros to correctly define and manage the ramp delay, thereby preventing the crashes associated with CPU DVFS.

Impact

The vulnerability could cause system crashes when using CPU DVFS, disrupting normal operation and potentially leading to a denial of service.