Re: [PATCH v2] powerpc/powernv/idle: Restore IAMR after idle

2019-02-28 Thread Gautham R Shenoy
Hello Russell, On Fri, Feb 08, 2019 at 10:11:03PM +1100, Russell Currey wrote: > Without restoring the IAMR after idle, execution prevention on POWER9 > with Radix MMU is overwritten and the kernel can freely execute userspace > without > faulting. > > This is necessary when returning from any s

Re: [PATCH v2] powerpc/powernv/idle: Restore IAMR after idle

2019-02-27 Thread Nicholas Piggin
Russell Currey's on February 8, 2019 9:11 pm: > Without restoring the IAMR after idle, execution prevention on POWER9 > with Radix MMU is overwritten and the kernel can freely execute userspace > without > faulting. > > This is necessary when returning from any stop state that modifies user > sta

Re: [PATCH v2] powerpc/powernv/idle: Restore IAMR after idle

2019-02-27 Thread Akshay Adiga
The changes look good to me. On Fri, Feb 08, 2019 at 10:11:03PM +1100, Russell Currey wrote: > Without restoring the IAMR after idle, execution prevention on POWER9 > with Radix MMU is overwritten and the kernel can freely execute userspace > without > faulting. > > This is necessary when return