Hi, On Wed, Jul 10, 2019 at 01:44:17PM +0800, Xi Ruoyao wrote: > Hello, > > When I try to build and run the latest mainline kernel, it Oops loading i915 > module: > > BUG: unable to handle page fault for address: ffffffff9edc1598 > #PF: supervisor write access in kernel mode > #PF: error_code(0x0003) - permissions violation > PGD 1a20c067 P4D 1a20c067 PUD 1a20d063 PMD 8000000019e000e1 > Oops: 0003 [#1] SMP PTI > > The complete log is attached. > > Bisection tells "x86/asm: Pin sensitive CR4 bits" (873d50d58) is the first "bad" > commit. I can revert it and also "x86/asm: Pin sensitive CR0 bits" (8dbec27a2) > to make the kernel "seems to" work. > > I'm not a kernel expert so I can't tell if there is a bug in Kees' patch, or his > patch exploits a bug in i915 or module loader. This seems to be a kernel bug introduced after v5.2, see https://lore.kernel.org/lkml/CAHk-=wjh+h_-fd-gJz=wor42ZNmqq46QnB90jyfzqmKLsLFWOg@xxxxxxxxxxxxxx/ -- ldv
