On Fri, Nov 26, 2021 at 03:39:25PM +0100, Lino Sanfilippo wrote: > The driver attempts to request and release the IO memory region for a uart > port twice: > > First during the probe() function devm_ioremap_resource() is used to > allocate and map the ports memory. > Then a combo of pl011_config_port() and pl011_release_port() is used to > request/release the same memory area. These functions are called by the > serial core as soon as the uart is registered/unregistered. > > However since the allocation request via devm_ioremap_resource() already > succeeds, the attempt to claim the memory again via pl011_config_port() > fails. This failure remains unnoticed, since the concerning return value is > not evaluated. > Later at module unload also the attempt to release the unclaimed memory > in pl011_release_port() fails. This time the failure results in a “Trying > to free nonexistent resource" warning printed by the serial core. > > Fix these issues by removing the callbacks that implement the redundant > memory allocation/release. I think you will also need the verify_port method to also deny changing port->mapbase. -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!
