[SRU][J/realtime][PATCH 1/1] x86/mm: Include spinlock_t definition in pgtable.

[Joseph Salisbury]

From: Sebastian Andrzej Siewior <bigeasy at linutronix.de>

BugLink: https://bugs.launchpad.net/bugs/1972899

This header file provides forward declartion for pgd_lock but does not
include the header defining its type. This works since the definition of
spinlock_t is usually included somehow via printk.

By trying to avoid recursive includes on PREEMPT_RT I avoided the loop
in printk and as a consequnce kernel/intel.c failed to compile due to
missing type definition.

Include the needed definition for spinlock_t.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy at linutronix.de>
Signed-off-by: Dave Hansen <dave.hansen at linux.intel.com>
Link: https://lkml.kernel.org/r/20211102165224.wpz4zyhsvwccx5p3@linutronix.de
(cherry picked from commit 35fa745286ac44ee26ed100c2bd2553368ad193b)
Signed-off-by: Joseph Salisbury <joseph.salisbury at canonical.com>
---
 arch/x86/include/asm/pgtable.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
index 448cd01eb3ec..a34430b7af4a 100644
--- a/arch/x86/include/asm/pgtable.h
+++ b/arch/x86/include/asm/pgtable.h
@@ -22,6 +22,7 @@
 #define pgprot_decrypted(prot)	__pgprot(__sme_clr(pgprot_val(prot)))
 
 #ifndef __ASSEMBLY__
+#include <linux/spinlock.h>
 #include <asm/x86_init.h>
 #include <asm/pkru.h>
 #include <asm/fpu/api.h>
-- 
2.34.1