path: root/arch
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authorJoerg Roedel <jroedel@suse.de>2018-07-18 11:41:07 +0200
committerThomas Gleixner <tglx@linutronix.de>2018-07-20 01:11:45 +0200
commitba0364e260ab37c02975557dbecc014a26072236 (patch)
treea7a9be4ea2d2df1e0e8ac983fcee4d522c0cf2bb /arch
parentb976690f5db26fbc7c2be413bfa0fbd270547a94 (diff)
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 <jroedel@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Pavel Machek <pavel@ucw.cz> Cc: "H . Peter Anvin" <hpa@zytor.com> Cc: linux-mm@kvack.org Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Brian Gerst <brgerst@gmail.com> Cc: David Laight <David.Laight@aculab.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Eduardo Valentin <eduval@amazon.com> Cc: Greg KH <gregkh@linuxfoundation.org> Cc: Will Deacon <will.deacon@arm.com> Cc: aliguori@amazon.com Cc: daniel.gruss@iaik.tugraz.at Cc: hughd@google.com Cc: keescook@google.com Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Waiman Long <llong@redhat.com> Cc: "David H . Gutteridge" <dhgutteridge@sympatico.ca> Cc: joro@8bytes.org Link: https://lkml.kernel.org/r/1531906876-13451-31-git-send-email-joro@8bytes.org
Diffstat (limited to 'arch')
1 files 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();