Commit-ID: ba0364e260ab37c02975557dbecc014a26072236 Gitweb: https://git.kernel.org/tip/ba0364e260ab37c02975557dbecc014a26072236 Author: Joerg Roedel <jroe...@suse.de> AuthorDate: Wed, 18 Jul 2018 11:41:07 +0200 Committer: Thomas Gleixner <t...@linutronix.de> CommitDate: Fri, 20 Jul 2018 01:11:45 +0200
x86/mm/pti: Clone entry-text again in pti_finalize() The mapping for entry-text might have changed in the kernel after it was cloned to the user page-table. Clone again to update the user page-table to bring the mapping in sync with the kernel again. Signed-off-by: Joerg Roedel <jroe...@suse.de> Signed-off-by: Thomas Gleixner <t...@linutronix.de> Tested-by: Pavel Machek <pa...@ucw.cz> Cc: "H . Peter Anvin" <h...@zytor.com> Cc: linux...@kvack.org Cc: Linus Torvalds <torva...@linux-foundation.org> Cc: Andy Lutomirski <l...@kernel.org> Cc: Dave Hansen <dave.han...@intel.com> Cc: Josh Poimboeuf <jpoim...@redhat.com> Cc: Juergen Gross <jgr...@suse.com> Cc: Peter Zijlstra <pet...@infradead.org> Cc: Borislav Petkov <b...@alien8.de> Cc: Jiri Kosina <jkos...@suse.cz> Cc: Boris Ostrovsky <boris.ostrov...@oracle.com> Cc: Brian Gerst <brge...@gmail.com> Cc: David Laight <david.lai...@aculab.com> Cc: Denys Vlasenko <dvlas...@redhat.com> Cc: Eduardo Valentin <edu...@amazon.com> Cc: Greg KH <gre...@linuxfoundation.org> Cc: Will Deacon <will.dea...@arm.com> Cc: aligu...@amazon.com Cc: daniel.gr...@iaik.tugraz.at Cc: hu...@google.com Cc: keesc...@google.com Cc: Andrea Arcangeli <aarca...@redhat.com> Cc: Waiman Long <ll...@redhat.com> Cc: "David H . Gutteridge" <dhgutteri...@sympatico.ca> Cc: j...@8bytes.org Link: https://lkml.kernel.org/r/1531906876-13451-31-git-send-email-j...@8bytes.org --- arch/x86/mm/pti.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/arch/x86/mm/pti.c b/arch/x86/mm/pti.c index fcfb815d420f..a536ecc91847 100644 --- a/arch/x86/mm/pti.c +++ b/arch/x86/mm/pti.c @@ -404,7 +404,7 @@ static void __init pti_setup_espfix64(void) /* * Clone the populated PMDs of the entry and irqentry text and force it RO. */ -static void __init pti_clone_entry_text(void) +static void pti_clone_entry_text(void) { pti_clone_pmds((unsigned long) __entry_text_start, (unsigned long) __irqentry_text_end, @@ -528,13 +528,18 @@ void __init pti_init(void) } /* - * Finalize the kernel mappings in the userspace page-table. + * Finalize the kernel mappings in the userspace page-table. Some of the + * mappings for the kernel image might have changed since pti_init() + * cloned them. This is because parts of the kernel image have been + * mapped RO and/or NX. These changes need to be cloned again to the + * userspace page-table. */ void pti_finalize(void) { /* - * Do this after all of the manipulation of the - * kernel text page tables are complete. + * We need to clone everything (again) that maps parts of the + * kernel image. */ + pti_clone_entry_text(); pti_clone_kernel_text(); }
