Commit-ID: ba0364e260ab37c02975557dbecc014a26072236 Gitweb: https://git.kernel.org/tip/ba0364e260ab37c02975557dbecc014a26072236 Author: Joerg Roedel <[email protected]> AuthorDate: Wed, 18 Jul 2018 11:41:07 +0200 Committer: Thomas Gleixner <[email protected]> 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 <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Tested-by: Pavel Machek <[email protected]> Cc: "H . Peter Anvin" <[email protected]> Cc: [email protected] Cc: Linus Torvalds <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Dave Hansen <[email protected]> Cc: Josh Poimboeuf <[email protected]> Cc: Juergen Gross <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Jiri Kosina <[email protected]> Cc: Boris Ostrovsky <[email protected]> Cc: Brian Gerst <[email protected]> Cc: David Laight <[email protected]> Cc: Denys Vlasenko <[email protected]> Cc: Eduardo Valentin <[email protected]> Cc: Greg KH <[email protected]> Cc: Will Deacon <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: Andrea Arcangeli <[email protected]> Cc: Waiman Long <[email protected]> Cc: "David H . Gutteridge" <[email protected]> Cc: [email protected] Link: https://lkml.kernel.org/r/[email protected] --- 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(); }
