Re: [PATCHv3 1/3] x86/mm: Move LDT remap out of KASLR region on 5-level paging

2018-12-03 Thread Kirill A. Shutemov
On Mon, Dec 03, 2018 at 11:01:00AM +0800, Baoquan He wrote: > It looks do-able, not sure if the test case is complicated or not, if > not hard, I can have a try. And I have some internal bugs, can focus on > this later. I saw you posted another patchset to fix xen issue, it may > not be needed any

Re: [PATCHv3 1/3] x86/mm: Move LDT remap out of KASLR region on 5-level paging

2018-12-02 Thread Baoquan He
Hi Kirill, On 11/23/18 at 06:58pm, Kirill A. Shutemov wrote: > > Thanks for this fix. One small concern is whether we can put LDT > > remap in other place, e.g shrink KASAN area and save one pgd size for > > it, Just from Redhat's enterprise relase point of view, we don't > > enable CONFIG_KASAN,

Re: [PATCHv3 1/3] x86/mm: Move LDT remap out of KASLR region on 5-level paging

2018-11-23 Thread Kirill A. Shutemov
On Sat, Nov 10, 2018 at 08:29:05PM +0800, Baoquan He wrote: > > diff --git a/Documentation/x86/x86_64/mm.txt > > b/Documentation/x86/x86_64/mm.txt > > index 702898633b00..75bff98928a8 100644 > > --- a/Documentation/x86/x86_64/mm.txt > > +++ b/Documentation/x86/x86_64/mm.txt > > @@ -34,23 +34,24 @@

Re: [PATCHv3 1/3] x86/mm: Move LDT remap out of KASLR region on 5-level paging

2018-11-10 Thread Baoquan He
On 10/26/18 at 03:28pm, Kirill A. Shutemov wrote: > On 5-level paging LDT remap area is placed in the middle of > KASLR randomization region and it can overlap with direct mapping, > vmalloc or vmap area. ~~~ We usually call it vmemmap. > > Let's move LDT just before d

Re: [PATCHv3 1/3] x86/mm: Move LDT remap out of KASLR region on 5-level paging

2018-11-02 Thread Andy Lutomirski
On Fri, Oct 26, 2018 at 5:29 AM Kirill A. Shutemov wrote: > > On 5-level paging LDT remap area is placed in the middle of > KASLR randomization region and it can overlap with direct mapping, > vmalloc or vmap area. > > Let's move LDT just before direct mapping which makes it safe for KASLR. > This

[PATCHv3 1/3] x86/mm: Move LDT remap out of KASLR region on 5-level paging

2018-10-26 Thread Kirill A. Shutemov
On 5-level paging LDT remap area is placed in the middle of KASLR randomization region and it can overlap with direct mapping, vmalloc or vmap area. Let's move LDT just before direct mapping which makes it safe for KASLR. This also allows us to unify layout between 4- and 5-level paging. We don't