Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 fixes from Catalin Marinas:
 "ACPI-related fixes for arm64:

   - GICC MADT entry validity check fix

   - Skip IRQ registration with pmu=off in an ACPI guest

   - struct acpi_pci_root_ops freeing on error path"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  ARM64/ACPI: Fix BAD_MADT_GICC_ENTRY() macro implementation
  drivers/perf: arm_pmu_acpi: avoid perf IRQ init when guest PMU is off
  ARM64: PCI: Fix struct acpi_pci_root_ops allocation failure path

3 files changed, 17 insertions, 4 deletions

diff --git a/arch/arm64/include/asm/acpi.h b/arch/arm64/include/asm/acpi.h
index 0e99978da3f0..59cca1d6ec54 100644
--- a/arch/arm64/include/asm/acpi.h
+++ b/arch/arm64/include/asm/acpi.h
@@ -23,9 +23,9 @@
 #define ACPI_MADT_GICC_LENGTH   \
         (acpi_gbl_FADT.header.revision < 6 ? 76 : 80)
 
-#define BAD_MADT_GICC_ENTRY(entry, end)                                         \
-        (!(entry) || (unsigned long)(entry) + sizeof(*(entry)) > (end) ||       \
-         (entry)->header.length != ACPI_MADT_GICC_LENGTH)
+#define BAD_MADT_GICC_ENTRY(entry, end)                                 \
+        (!(entry) || (entry)->header.length != ACPI_MADT_GICC_LENGTH || \
+        (unsigned long)(entry) + ACPI_MADT_GICC_LENGTH > (end))
 
 /* Basic configuration for ACPI */
 #ifdef  CONFIG_ACPI
diff --git a/arch/arm64/kernel/pci.c b/arch/arm64/kernel/pci.c
index 4f0e3ebfea4b..c7e3e6387a49 100644
--- a/arch/arm64/kernel/pci.c
+++ b/arch/arm64/kernel/pci.c
@@ -191,8 +191,10 @@ struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root)
                 return NULL;
 
         root_ops = kzalloc_node(sizeof(*root_ops), GFP_KERNEL, node);
-        if (!root_ops)
+        if (!root_ops) {
+                kfree(ri);
                 return NULL;
+        }
 
         ri->cfg = pci_acpi_setup_ecam_mapping(root);
         if (!ri->cfg) {
diff --git a/drivers/perf/arm_pmu_acpi.c b/drivers/perf/arm_pmu_acpi.c
index 34c862f213c7..0a9b78705ee8 100644
--- a/drivers/perf/arm_pmu_acpi.c
+++ b/drivers/perf/arm_pmu_acpi.c
@@ -29,6 +29,17 @@ static int arm_pmu_acpi_register_irq(int cpu)
                 return -EINVAL;
 
         gsi = gicc->performance_interrupt;
+
+        /*
+         * Per the ACPI spec, the MADT cannot describe a PMU that doesn't
+         * have an interrupt. QEMU advertises this by using a GSI of zero,
+         * which is not known to be valid on any hardware despite being
+         * valid per the spec. Take the pragmatic approach and reject a
+         * GSI of zero for now.
+         */
+        if (!gsi)
+                return 0;
+
         if (gicc->flags & ACPI_MADT_PERFORMANCE_IRQ_MODE)
                 trigger = ACPI_EDGE_SENSITIVE;
         else