[PATCH 2/3] x86/pti: Call pti_init() after mark_readonly()

[Joerg Roedel <joro@8bytes.org>]

From: Joerg Roedel <jroedel@suse.de>

PTI init code clones some parts of the kernel mappings to the user-space
page-table. For the kernel and user-space page-table to be consistent,
the cloning should happen when the relevant parts of the kernel
page-table are finished, which is right after mark_readonly() returns.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
---
 init/main.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/init/main.c b/init/main.c
index 3b4ada1..0b5d0f1 100644
--- a/init/main.c
+++ b/init/main.c
@@ -524,8 +524,6 @@ static void __init mm_init(void)
 	ioremap_huge_init();
 	/* Should be run before the first non-init thread is created */
 	init_espfix_bsp();
-	/* Should be run after espfix64 is set up. */
-	pti_init();
 }
 
 asmlinkage __visible void __init start_kernel(void)
@@ -1065,6 +1063,12 @@ static int __ref kernel_init(void *unused)
 	jump_label_invalidate_initmem();
 	free_initmem();
 	mark_readonly();
+	/*
+	 * Kernel text/rodata/data sections have the right protections
+	 * now. If necessary, init PTI and clone the relevant pieces
+	 * to the user-space page-table.
+	 */
+	pti_init();
 	system_state = SYSTEM_RUNNING;
 	numa_default_policy();
 
-- 
2.7.4