Re: [RFC PATCH 0/3] Use per-CPU temporary mappings for patching

2020-03-24 Thread Andrew Donnellan
On 23/3/20 3:52 pm, Christopher M. Riedl wrote: When compiled with CONFIG_STRICT_KERNEL_RWX, the kernel must create temporary mappings when patching itself. These mappings temporarily override the strict RWX text protections to permit a write. Currently, powerpc allocates a per-CPU VM area for pa

Re: [RFC PATCH 0/3] Use per-CPU temporary mappings for patching

2020-03-24 Thread Christophe Leroy
Le 23/03/2020 à 15:04, Christophe Leroy a écrit : On 03/23/2020 11:30 AM, Christophe Leroy wrote: On 03/23/2020 04:52 AM, Christopher M. Riedl wrote: When compiled with CONFIG_STRICT_KERNEL_RWX, the kernel must create temporary mappings when patching itself. These mappings temporarily ov

Re: [RFC PATCH 0/3] Use per-CPU temporary mappings for patching

2020-03-23 Thread Christophe Leroy
Le 23/03/2020 à 17:49, Christopher M Riedl a écrit : On March 23, 2020 9:04 AM Christophe Leroy wrote: On 03/23/2020 11:30 AM, Christophe Leroy wrote: On 03/23/2020 04:52 AM, Christopher M. Riedl wrote: When compiled with CONFIG_STRICT_KERNEL_RWX, the kernel must create temporary ma

Re: [RFC PATCH 0/3] Use per-CPU temporary mappings for patching

2020-03-23 Thread Christophe Leroy
On 03/23/2020 11:30 AM, Christophe Leroy wrote: On 03/23/2020 04:52 AM, Christopher M. Riedl wrote: When compiled with CONFIG_STRICT_KERNEL_RWX, the kernel must create temporary mappings when patching itself. These mappings temporarily override the strict RWX text protections to permit a wr

Re: [RFC PATCH 0/3] Use per-CPU temporary mappings for patching

2020-03-23 Thread Christophe Leroy
On 03/23/2020 04:52 AM, Christopher M. Riedl wrote: When compiled with CONFIG_STRICT_KERNEL_RWX, the kernel must create temporary mappings when patching itself. These mappings temporarily override the strict RWX text protections to permit a write. Currently, powerpc allocates a per-CPU VM area

[RFC PATCH 0/3] Use per-CPU temporary mappings for patching

2020-03-22 Thread Christopher M. Riedl
When compiled with CONFIG_STRICT_KERNEL_RWX, the kernel must create temporary mappings when patching itself. These mappings temporarily override the strict RWX text protections to permit a write. Currently, powerpc allocates a per-CPU VM area for patching. Patching occurs as follows: 1. Ma