| From | Andy Lutomirski <> | Date | Fri, 13 Jul 2018 16:25:25 -0700 | Subject | Re: [PATCH 28/39] x86/mm/pti: Keep permissions when cloning kernel text in pti_clone_kernel_text() |
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On Wed, Jul 11, 2018 at 4:29 AM, Joerg Roedel <joro@8bytes.org> wrote: > From: Joerg Roedel <jroedel@suse.de> > > Mapping the kernel text area to user-space makes only sense > if it has the same permissions as in the kernel page-table. > If permissions are different this will cause a TLB reload > when using the kernel page-table, which is as good as not > mapping it at all. > > On 64-bit kernels this patch makes no difference, as the > whole range cloned by pti_clone_kernel_text() is mapped RO > anyway. On 32 bit there are writeable mappings in the range, > so just keep the permissions as they are.
Reviewed-by: Andy Lutomirski <luto@kernel.org>
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