On 04/25/14 at 12:53pm, Matt Fleming wrote: > On Thu, 24 Apr, at 05:36:58PM, Dave Young wrote: > > earlyprint=efi,keep results a kernel hang after "Freeing unused kernel memory" > > Are you sure it hangs and it's not just that nothing is output to the > console after that point? There's other kernel messages without appending ,keep. Also console=ttyS0 does not work with earlyprintk=efi,keep, removing ,keep it works well. > > > Actually efi earlyprintk is using __init functions such as early_ioremap etc. > > Thus efi earlyconsole can not be kept. > > Urgh, good point, that's a bug. However I'm sure I've had this working > in the past and have in fact used it to debug stuff. > > Could you try and fix this up so it works with 'keep'? Will do. I want use ioremap when it is available but it's hard to decide where to add the code. I'm thinking to do below: 1. ioremap the whole framebuffer like: efi_fb = ioremap(lfb_base, lfb_size) in the function efi_enter_virtual_mode because ioremap should be usable then. 2. add two functions for earlyprintk use (scrollup, write, etc.) __init_refok void * get_vaddr(unsigned long start, unsigned long len) { unsigned long base; base = boot_params.screen_info.lfb_base; if (efi_fb) return (efi_fb + start - base); else return early_ioremap(start, len); } __init_refok void put_vaddr(void *addr, unsigned long len) { if (!efi_fb) early_iounmap(addr, len); } But it does not sound good to add the ioremap in enter virtual mode funtion. Please help if you have any other better idea. Thanks Dave -- To unsubscribe from this list: send the line "unsubscribe linux-efi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html