On Fri, Apr 29, 2016 at 11:30 PM, Russell King - ARM Linux <linux@xxxxxxxxxxxxxxxx> wrote: > On Fri, Apr 29, 2016 at 08:26:00PM +0530, Pratyush Anand wrote: >> Hi Russell, >> >> On Thu, Apr 28, 2016 at 2:58 PM, Russell King >> <rmk+kernel@xxxxxxxxxxxxxxxx> wrote: >> > Advertise the location of bootable RAM to kexec-tools. kexec needs to >> > know where it can place the kernel in RAM, and so be executable when >> > the system needs to jump into it. >> > >> > Advertise these areas in /proc/iomem with a "System RAM (boot alias)" >> > tag. >> > >> > Signed-off-by: Russell King <rmk+kernel@xxxxxxxxxxxxxxxx> >> >> Can you please also share git tree path of corresponding kexec-tools changes? >> >> Could it be a better idea (if things in user space become simpler) >> that in stead of patch 5 and 6, we pass arch_phys_to_idmap_offset to >> user space, and then user space manipulates existing "Crash kernel" >> and "System RAM" resources. > > Given that it's only _one_ platform right now, I don't think that > additional complexity is worth it. It means that we have to invent Probably, I could not communicate it well. I was not trying to have *additional* complexity. Wanted to see if things could be simpler rather. So this is what my understanding was: -- We create one patch to pass arch_phys_to_idmap_offset to user space (say in /sys/kernel/bootmem_idmap_offset) -- We do not use patch 5,6,11 and 12 of this series. Probably few more content of the series will go away. -- In kexec-tools code , we read /sys/kernel/bootmem_idmap_offset and add that value in "start" and "end" of "Crash Kernel" and "System RAM" resources. > some API to do it, and I don't see why userspace should even care > about having the delta exported - especially when the conversion > may not be as trivial. > Yes, I agree, if translation is not trivial like that of keystone, then what I am proposing will not work. Reviewed-by: Pratyush Anand <panand@xxxxxxxxxx> -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
