x86/apic: Sanitize return value of apic.set_apic_id()

The set_apic_id() callback returns an unsigned long value which is handed
in to apic_write() as the value argument u32.

Adjust the return value so it returns u32 right away.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Yu Chen <yu.c.chen@intel.com>
Acked-by: Juergen Gross <jgross@suse.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Alok Kataria <akataria@vmware.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Rui Zhang <rui.zhang@intel.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Len Brown <lenb@kernel.org>
Link: https://lkml.kernel.org/r/20170913213153.437208268@linutronix.de

arch/x86/include/asm/apic.h

@@ -305,7 +305,7 @@ struct apic {
 
 	unsigned int (*get_apic_id)(unsigned long x);
 	/* Can't be NULL on 64-bit */
-	unsigned long (*set_apic_id)(unsigned int id);
+	u32 (*set_apic_id)(unsigned int id);
 
 	int (*cpu_mask_to_apicid)(const struct cpumask *cpumask,
 				  struct irq_data *irqdata,

arch/x86/kernel/apic/apic_flat_64.c

@@ -119,7 +119,7 @@ static unsigned int flat_get_apic_id(unsigned long x)
 	return (x >> 24) & 0xFF;
 }
 
-static unsigned long set_apic_id(unsigned int id)
+static u32 set_apic_id(unsigned int id)
 {
 	return (id & 0xFF) << 24;
 }

arch/x86/kernel/apic/apic_numachip.c

@@ -38,7 +38,7 @@ static unsigned int numachip1_get_apic_id(unsigned long x)
 	return id;
 }
 
-static unsigned long numachip1_set_apic_id(unsigned int id)
+static u32 numachip1_set_apic_id(unsigned int id)
 {
 	return (id & 0xff) << 24;
 }
@@ -51,7 +51,7 @@ static unsigned int numachip2_get_apic_id(unsigned long x)
 	return ((mcfg >> (28 - 8)) & 0xfff00) | (x >> 24);
 }
 
-static unsigned long numachip2_set_apic_id(unsigned int id)
+static u32 numachip2_set_apic_id(unsigned int id)
 {
 	return id << 24;
 }

arch/x86/kernel/apic/x2apic.h

@@ -4,6 +4,6 @@ int x2apic_apic_id_valid(int apicid);
 int x2apic_apic_id_registered(void);
 void __x2apic_send_IPI_dest(unsigned int apicid, int vector, unsigned int dest);
 unsigned int x2apic_get_apic_id(unsigned long id);
-unsigned long x2apic_set_apic_id(unsigned int id);
+u32 x2apic_set_apic_id(unsigned int id);
 int x2apic_phys_pkg_id(int initial_apicid, int index_msb);
 void x2apic_send_IPI_self(int vector);

arch/x86/kernel/apic/x2apic_phys.c

@@ -121,7 +121,7 @@ unsigned int x2apic_get_apic_id(unsigned long id)
 	return id;
 }
 
-unsigned long x2apic_set_apic_id(unsigned int id)
+u32 x2apic_set_apic_id(unsigned int id)
 {
 	return id;
 }

arch/x86/kernel/apic/x2apic_uv_x.c

@@ -547,7 +547,7 @@ static unsigned int x2apic_get_apic_id(unsigned long x)
 	return id;
 }
 
-static unsigned long set_apic_id(unsigned int id)
+static u32 set_apic_id(unsigned int id)
 {
 	/* CHECKME: Do we need to mask out the xapic extra bits? */
 	return id;

arch/x86/xen/apic.c

@@ -30,7 +30,7 @@ static unsigned int xen_io_apic_read(unsigned apic, unsigned reg)
 	return 0xfd;
 }
 
-static unsigned long xen_set_apic_id(unsigned int x)
+static u32 xen_set_apic_id(unsigned int x)
 {
 	WARN_ON(1);
 	return x;