ideapad-laptop

  1. Bug #2034477
  2. Comment #112

Comment 112 for bug 2034477

Revision history for this message
In , mario.limonciello (mario.limonciello-linux-kernel-bugs) wrote :

Excellent find!

If it's using "NULL legacy PIC" that means that 8259 wasn't programmed properly by BIOS (Linux currently expects it). I've seen this in the past, and it's always been fixed by BIOS.

If Hans' hack doesn't work, another hack idea to confirm it is to program registers for it from a "broken" Linux kernel and then kexec into "another" kernel and see if it helps.

You can use any port I/O tools to write "0x68" to port "0x21" followed by "0x1" to port "0x21" to do this.