When I trace kernel in head.S I found problems that may be caused by __turn_mmu_on. Any idea ?
/* * Enable the MMU. This completely changes the structure of the visible * memory space. You will not be able to trace execution through this. * If you have an enquiry about this, *please* check the linux-arm-kernel * mailing list archives BEFORE sending another post to the list. */ The main issue here is that developers do not realise what “enabling the MMU” means. It means that all of the addressable memory will change, and this normally means various regions you’d like to write to no longer have a valid mapping and appear not to exist. If there is debugging code present that doesn’t cater for a complete change in the memory structure, then that debugging code is buggy. The best advice is if you’re using your own debugging code, remove it. Use the debugging printascii() stuff for your platform in arch/arm/kernel/debug-armv.S (enabled by CONFIG_DEBUG_LL) and drop a printascii() into printk() (kernel/printk.c) just after the vsprintf() call, and monitor the relevant serial port. • Whe
