On 02-06-18 21:31, Andrew Lunn wrote: > On Sat, Jun 02, 2018 at 09:48:47PM +0300, Timo Jyrinki wrote: >> 2018-06-02 18:55 GMT+03:00 Ian Campbell <i...@debian.org>: >>> You need to append a dtb and then encode in u-boot's uImage format. >>> e.g. >>> >>> cat arch/arm/boot/zImage arch/arm/boot/dts/kirkwood-ts419-6281.dtb > x >>> sudo mkimage -A arm -T kernel -O linux -C none -a 0x8000 -e 0x8000 -d x >>> uImage >> >> Thank you! Now it's all coming back to me, I'm not sure if I've played >> with these since Neo FreeRunner times. >> >> So the good news is that with this kernel >> kernel-kirkwood-ts219-6282-split3gopt from >> https://people.debian.org/~timo/qnap/ (initrd from >> http://ftp.debian.org/debian/dists/stretch/main/installer-armel/current/images/kirkwood/network-console/qnap/ts-21x/) >> I'm getting full 1GB RAM without the errors! > > Cool. Thanks for testing. > > Now, the question is, is this an O.K. workaround? Or do we need to > figure out why highmem breaks on Kirkwood?
For me the most important thing is to have a workable installation that can be kept up to date. OTOH I'm also interested in what change introduced the instability. I did some research into when VMSPLIT_3G_OPT was introduced, which AFAICT was after linux-image-4.3.0-0.bpo.1-kirkwood (linux-4.3.5). Version linux-image-4.3.0-0.bpo.1-kirkwood is stable with 1024M memory. The option VMSPLIT_3G_OPT affects CONFIG_PAGE_OFFSET. For both the linux-image-4.3.0-0.bpo.1-kirkwood and linux-image-4.3.0-0.bpo.1-kirkwood kernels the setting is the same epping@threis:~$ grep PAGE_OFFSET /boot/config-4.* /boot/config-4.16.0-0.bpo.1-marvell:CONFIG_PAGE_OFFSET=0xC0000000 /boot/config-4.3.0-0.bpo.1-kirkwood:CONFIG_PAGE_OFFSET=0xC0000000 epping@threis:~$ It seems to me there is something else that changed after either after linux 4.3 or with the flavour change from kirkwood to marvell. comparing kernel.org v4.3.5 and v4.7.1 there are some changed to kirkwood-ts219-6282.dts related to something called mbus and pcie. grep-ing the kernel arch/arm source for "external abort on linefetch" there are 2 files found, arch/arm/mm/fsr-2level.c and arch/arm/mach-integrator/pci_v3.c fsr is realoed to fault status register and pci_v3 to pci. I'm wondering if there is a relation between the device-tree changes and the error messages, that is not triggered when memory size is restricted. Would it be save to boot 4.16 kernel with 4.3 dtb? been at this for way to long, time to go to sleep. > Andrew GRTNX, RobJE
