kernel7.img can't boot on 4.11.0-rc3, but works fine on 4.10.5

[jeffersonchua]

Hi,

Tried to compile kernel for 32-bit 4.11.0-rc3, but the compiled kernel7.img won't boot on pi3. There's nothing displayed on the console except for an 'underscore".

The same config compiled for 4.10.5 booted up and worked fine on pi3.

Both config attached. What am I missing?

Thanks,
Jeff

config-4105.txt
config-4110rc3.txt

[popcornmix]

Can you test with the default config? (bcm2709_defconfig)

[timpro]

Are you using any overlays ? Those seem to be missing in 4.11 .

[jeffersonchua]

Can you test with the default config? (bcm2709_defconfig)
Tested, still can't boot.

Are you using any overlays ? Those seem to be missing in 4.11 .

I'm only specifying device_tree=bcm2710-rpi-3-b.dtb in config.txt
and copying arch/arm/boot/dts/overlays/*.dtbo to /boot/overlays

Jeff

[pelwell]

With the serial port connected to a Pi 2 I get output as far as:

[    1.142449] Waiting for root device /dev/mmcblk0p2...

then it stalls.

I'm investigating.

[pelwell]

Am I right in thinking that you are using the mkknlimg script? In the 4.11 tree it is failing to detect some downstream-only strings, which is causing it to load the upstream dtb (e.g. bcm2836-rpi-2-b.dtb) and failing because the kernel doesn't match.

Official RPi firmware builds no longer use mkknlimg, but my personal build script still does which is why I saw the same problem. Try replacing the mkknlimg step with:

cp arch/arm/boot/zImage kernel7.img

or

sudo cp arch/arm/boot/zImage /boot/kernel7.img

and see if you can boot again. You won't need to rebuild the modules - just copy the new kernel onto the SD card. Alternatively, you can force the downstream DTB in config.txt:

[pi3]
device_tree=bcm2710-rpi-3-b.dtb
[pi2]
device_tree=bcm2709-rpi-2-b.dtb
[all]

[pelwell]

The mkknlimg in the 4.11 tree should now detect a downstream build again.

[timpro]

Are you using any overlays ? Those seem to be missing in 4.11 .

Sorry for the noise, there is a quirk in the Giithub web interface: the "overlays" subdirectory is "missing" from the top of arch/arm/boot/dts because the list of files gets cut short after "omap*" at the bottom. I can navigate to it manually though.

[Electron752]

I'm getting a crash on arm64 now with the overlays.

It's crashing in a DMA/CMA related path to the new mmc driver.

[pelwell]

It's a WARN rather than a crash, and it's next on the list to look at. My current thinking of that this is another system-wide change that has affected all users of CMA, and the sdhost driver is just the first, but I should know more tomorrow.

[pelwell]

And can you try to stay on-topic?

[jeffersonchua]

Am I right in thinking that you are using the mkknlimg script?

Yes! I'm using "scripts/mkknlimg arch/arm/boot/zImage /boot/kernel7.img"

cp arch/arm/boot/zImage kernel7,img

Interesting ... didn't know that. Learning something new everyday!

The mkknlimg in the 4.11 tree should now detect a downstream build again.

Ok, will try that.

Thanks,
Jeff.

[Electron752]

I'm still having troubling, but I think I know what to do now. Give me a bit.

[jeffersonchua]

cp arch/arm/boot/zImage kernel7,img
The mkknlimg in the 4.11 tree should now detect a downstream build again.

I just tried both, still showing just "_" (underscore) at bootup.

I'm going back to test using default config bcm2709_defconfig.

Jeff

[popcornmix]

cp arch/arm/boot/zImage kernel7,img

Note that should be kernel7.img