irqchip/gic-v3-its: Check that all RDs have the same property table

commit f842ca8e9c8a80d07f5589536311250d7d6018f9 upstream

If booting with LPIs enabled, all the redistributors must have the
exact same property table. No ifs, no buts.
Tested-by: NJeremy Linton <jeremy.linton@arm.com>
Tested-by: NBhupesh Sharma <bhsharma@redhat.com>
Tested-by: NLei Zhang <zhang.lei@jp.fujitsu.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: NZou Cao <zoucao@linux.alibaba.com>
Reviewed-by: NBaoyou Xie <xie.baoyou@linux.alibaba.com>

drivers/irqchip/irq-gic-v3-its.c

@@ -2095,6 +2095,15 @@ static void its_cpu_init_lpis(void)
 	val = readl_relaxed(rbase + GICR_CTLR);
 	if ((gic_rdists->flags & RDIST_FLAGS_RD_TABLES_PREALLOCATED) &&
 	    (val & GICR_CTLR_ENABLE_LPIS)) {
+		/*
+		 * Check that we get the same property table on all
+		 * RDs. If we don't, this is hopeless.
+		 */
+		paddr = gicr_read_propbaser(rbase + GICR_PROPBASER);
+		paddr &= GENMASK_ULL(51, 12);
+		if (WARN_ON(gic_rdists->prop_table_pa != paddr))
+			add_taint(TAINT_CRAP, LOCKDEP_STILL_OK);
+
 		paddr = gicr_read_pendbaser(rbase + GICR_PENDBASER);
 		paddr &= GENMASK_ULL(51, 16);