x86/mm: Initialize PGD cache during mm initialization

Poking-mm initialization might require to duplicate the PGD in early
stage. Initialize the PGD cache earlier to prevent boot failures.

Reported-by: kernel test robot <[email protected]>
Signed-off-by: Nadav Amit <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Rick Edgecombe <[email protected]>
Cc: Rik van Riel <[email protected]>
Cc: Stephen Rothwell <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Fixes: 4fc19708b165 ("x86/alternatives: Initialize temporary mm for patching")
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>

1 files changed, 3 insertions, 0 deletions

diff --git a/init/main.c b/init/main.c
index 95dd9406ee31..9dc2f3b4f753 100644
--- a/init/main.c
+++ b/init/main.c
@@ -506,6 +506,8 @@ void __init __weak mem_encrypt_init(void) { }
 
 void __init __weak poking_init(void) { }
 
+void __init __weak pgd_cache_init(void) { }
+
 bool initcall_debug;
 core_param(initcall_debug, initcall_debug, bool, 0644);
 
@@ -537,6 +539,7 @@ static void __init mm_init(void)
 	init_espfix_bsp();
 	/* Should be run after espfix64 is set up. */
 	pti_init();
+	pgd_cache_init();
 }
 
 void __init __weak arch_call_rest_init(void)