Re: [PATCH 2/2] x86/mm: Introduce 'no5lvl' kernel parameter

2018-05-15 Thread Thomas Gleixner
On Tue, 15 May 2018, Kirill A. Shutemov wrote: > On Sun, May 13, 2018 at 09:55:00PM +, Thomas Gleixner wrote: > > On Fri, 11 May 2018, Kirill A. Shutemov wrote: > > > --- a/arch/x86/kernel/cpu/common.c > > > +++ b/arch/x86/kernel/cpu/common.c > > > @@ -1008,6 +1008,12 @@ static void __init ear

Re: [PATCH 2/2] x86/mm: Introduce 'no5lvl' kernel parameter

2018-05-14 Thread Kirill A. Shutemov
On Sun, May 13, 2018 at 09:55:00PM +, Thomas Gleixner wrote: > On Fri, 11 May 2018, Kirill A. Shutemov wrote: > > --- a/arch/x86/kernel/cpu/common.c > > +++ b/arch/x86/kernel/cpu/common.c > > @@ -1008,6 +1008,12 @@ static void __init early_identify_cpu(struct > > cpuinfo_x86 *c) > > */ >

Re: [PATCH 2/2] x86/mm: Introduce 'no5lvl' kernel parameter

2018-05-13 Thread Thomas Gleixner
On Fri, 11 May 2018, Kirill A. Shutemov wrote: > --- a/arch/x86/kernel/cpu/common.c > +++ b/arch/x86/kernel/cpu/common.c > @@ -1008,6 +1008,12 @@ static void __init early_identify_cpu(struct > cpuinfo_x86 *c) >*/ > setup_clear_cpu_cap(X86_FEATURE_PCID); > #endif > + > +#ifdef CONFIG

[PATCH 2/2] x86/mm: Introduce 'no5lvl' kernel parameter

2018-05-11 Thread Kirill A. Shutemov
The kernel parameter allows to force kernel to use 4-level paging even if hardware and kernel support 5-level paging. The option may be useful to workaround regressions related to 5-level paging. Signed-off-by: Kirill A. Shutemov --- Documentation/admin-guide/kernel-parameters.txt | 3 +++ arc