s390/pci: add error message for UID collision

When UID checking was turned off during runtime in the underlying
hypervisor, a PCI device may be attached with the same UID. This is
already detected but happens silently. Add an error message so it can
more easily be understood why a device was not added.

Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

diff --git a/arch/s390/pci/pci.c b/arch/s390/pci/pci.c
index c7fea9b..4901f5d 100644 (file)
--- a/arch/s390/pci/pci.c
+++ b/arch/s390/pci/pci.c
@@ -27,6 +27,7 @@
 #include <linux/seq_file.h>
 #include <linux/jump_label.h>
 #include <linux/pci.h>
+#include <linux/printk.h>
 
 #include <asm/isc.h>
 #include <asm/airq.h>
@@ -659,6 +660,8 @@ static int zpci_alloc_domain(struct zpci_dev *zdev)
                spin_lock(&zpci_domain_lock);
                if (test_bit(zdev->domain, zpci_domain)) {
                        spin_unlock(&zpci_domain_lock);
+                       pr_err("Adding PCI function %08x failed because domain %04x is already assigned\n",
+                               zdev->fid, zdev->domain);
                        return -EEXIST;
                }
                set_bit(zdev->domain, zpci_domain);