On Thu, Dec 12, 2019 at 11:57 AM Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> wrote: > > On Mon, Dec 09, 2019 at 05:38:01PM -0800, syzbot wrote: > > syzbot has bisected this bug to: > > > > commit bd94c4077a0b2ecc35562c294f80f3659ecd8499 > > Author: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx> > > Date: Wed Oct 28 03:46:05 2015 +0000 > > > > serial: support 16-bit register interface for console > > That would be because that is when this function was added to the kernel > :) > > Again, you are asking the kernel to write to a bad place in memory, and > then crash when that happens. That sounds like the correct > functionality to me... This looks like: #syz dup: BUG: unable to handle kernel NULL pointer dereference in mem_serial_out Let's continue in that thread.