Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull irqchip fix from Thomas Gleixner:
 "A single fix to prevent allocating excessive memory in the GIC/ITS
  driver.

  While the subject of the patch might suggest otherwise this is a real
  fix as some SoCs exceed the memory allocation limits and fail to boot"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/gic-v3-its: Cap lpi_id_bits to reduce memory footprint

1 files changed, 3 insertions, 1 deletions

diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index 316a57530f6d..c2df341ff6fa 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -1439,6 +1439,7 @@ static struct irq_chip its_irq_chip = {
  * The consequence of the above is that allocation is cost is low, but
  * freeing is expensive. We assumes that freeing rarely occurs.
  */
+#define ITS_MAX_LPI_NRBITS      16 /* 64K LPIs */
 
 static DEFINE_MUTEX(lpi_range_lock);
 static LIST_HEAD(lpi_range_list);
@@ -1625,7 +1626,8 @@ static int __init its_alloc_lpi_tables(void)
 {
         phys_addr_t paddr;
 
-        lpi_id_bits = GICD_TYPER_ID_BITS(gic_rdists->gicd_typer);
+        lpi_id_bits = min_t(u32, GICD_TYPER_ID_BITS(gic_rdists->gicd_typer),
+                                ITS_MAX_LPI_NRBITS);
         gic_rdists->prop_page = its_allocate_prop_table(GFP_NOWAIT);
         if (!gic_rdists->prop_page) {
                 pr_err("Failed to allocate PROPBASE\n");