I have an iMac mid 2011 running OSX and I am trying to install Arch Linux following this guide. I successfully set up a dual boot last year following a similar procedure but now I can't even start since I get a kernel panic while booting from the live usb installation of archiso: right before the login prompt. I'm 100% sure the image is not corrupted (I checked the signature and booted it on another pc).
Since last year it worked I tried every old release and I isolated the one that introduced the problem: it's 2015-05-01 kernel 4.0.1. Older versions boot fine and I can complete the installation but after a restart I get the kernel panic anyway.
I don't know what to do because I can't change any setting on the archiso image and the stack trace goes so fast I can't even record it: in a glimpse I have noticed "null pointer dereference", "scheduling while atomic" and "fixing recursive fault but reboot is needed”.
How can I debug it? And, possibly, how do I solve this issue?