Messages in this thread | | | Date | Wed, 6 Dec 2017 21:56:05 +0100 | From | Ingo Molnar <> | Subject | Re: [patch 33/60] x86/mm/kpti: Allocate a separate user PGD |
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* Borislav Petkov <bp@suse.de> wrote:
> On Mon, Dec 04, 2017 at 03:07:39PM +0100, Thomas Gleixner wrote: > > From: Dave Hansen <dave.hansen@linux.intel.com> > > > > Kernel page table isolation requires to have two PGDs. One for the kernel, > > which contains the full kernel mapping plus the user space mapping and one > > for user space which contains the user space mappings and the minimal set > > of kernel mappings which are required by the architecture to be able to > > transition from and to user space. > > > > Add the necessary preliminaries. > > > > [ tglx: Split out from the big kaiser dump ] > > > > Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> > > Signed-off-by: Thomas Gleixner <tglx@linutronix.de> > > > > --- > > arch/x86/kernel/head_64.S | 30 +++++++++++++++++++++++++++--- > > arch/x86/mm/pgtable.c | 16 ++++++++++++++-- > > 2 files changed, 41 insertions(+), 5 deletions(-) > > ... > > > --- a/arch/x86/mm/pgtable.c > > +++ b/arch/x86/mm/pgtable.c > > @@ -355,14 +355,26 @@ static inline void _pgd_free(pgd_t *pgd) > > kmem_cache_free(pgd_cache, pgd); > > } > > #else > > + > > +#ifdef CONFIG_KERNEL_PAGE_TABLE_ISOLATION > > +/* > > + * Instead of one pgd, we aquire two pgds. Being order-1, it is > > "acquire"
Fixed. I also did a s/pgd/PGD
> Otherwise: > > Reviewed-by: Borislav Petkov <bp@suse.de>
Thanks!
Ingo
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