On 8/17/2024 7:13 PM, Selvarasu Ganesan wrote: > On 8/17/2024 10:47 AM, Greg KH wrote: >> On Fri, Aug 16, 2024 at 09:13:09PM +0530, Selvarasu Ganesan wrote: >>> On 8/16/2024 3:25 PM, Greg KH wrote: >>>> On Thu, Aug 15, 2024 at 12:18:31PM +0530, Selvarasu Ganesan wrote: >>>>> This commit addresses an issue where the USB core could access an >>>>> invalid event buffer address during runtime suspend, potentially causing >>>>> SMMU faults and other memory issues in Exynos platforms. The problem >>>>> arises from the following sequence. >>>>> 1. In dwc3_gadget_suspend, there is a chance of a timeout when >>>>> moving the USB core to the halt state after clearing the >>>>> run/stop bit by software. >>>>> 2. In dwc3_core_exit, the event buffer is cleared regardless of >>>>> the USB core's status, which may lead to an SMMU faults and >>>>> other memory issues. if the USB core tries to access the event >>>>> buffer address. >>>>> >>>>> To prevent this hardware quirk on Exynos platforms, this commit ensures >>>>> that the event buffer address is not cleared by software when the USB >>>>> core is active during runtime suspend by checking its status before >>>>> clearing the buffer address. >>>>> >>>>> Cc: stable@xxxxxxxxxxxxxxx # v6.1+ >>>> Any hint as to what commit id this fixes? >>>> >>>> thanks, >>>> >>>> greg k-h >>> Hi Greg, >>> >>> This issue is not related to any particular commit. The given fix is >>> address a hardware quirk on the Exynos platform. And we require it to be >>> backported on stable kernel 6.1 and above all stable kernel. >> If it's a hardware quirk issue, why are you restricting it to a specific >> kernel release and not a specific kernel commit? Why not 5.15? 5.4? > Hi Greg, > > I mentioned a specific kernel because our platform is set to be tested > and functioning with kernels 6.1 and above, and the issue was reported > with these kernel versions. However, we would be fine if all stable > kernels, such as 5.4 and 5.15, were backported. In this case, if you > need a new patch version to update the Cc tag for all stable kernels, > please suggest the Cc tag to avoid confusion in next version. > > Thanks, > Selva Hi Greg, Would you like to provide any feedback or suggestions regarding the my last comments mentioned above? Thanks, Selva >> thanks, >> >> greg k-h >> >> >
