svn commit: r284012 - head/sys/dev/pci

[Hans Petter Selasky]

Author: hselasky
Date: Fri Jun  5 06:23:03 2015
New Revision: 284012
URL: https://svnweb.freebsd.org/changeset/base/284012

Log:
  Disable VGA PCI interrupts until a chipset driver is loaded for VGA
  PCI devices. Else unhandled display adapter interrupts might freeze
  the CPU or consume a lot of CPU.
  
  PR:		156596
  MFC after:	1 week

Modified:
  head/sys/dev/pci/vga_pci.c

Modified: head/sys/dev/pci/vga_pci.c
==============================================================================
--- head/sys/dev/pci/vga_pci.c	Fri Jun  5 06:06:07 2015	(r284011)
+++ head/sys/dev/pci/vga_pci.c	Fri Jun  5 06:23:03 2015	(r284012)
@@ -126,6 +126,13 @@ vga_pci_is_boot_display(device_t dev)
 	if ((config & (PCIM_CMD_PORTEN | PCIM_CMD_MEMEN)) == 0)
 		return (0);
 
+	/*
+	 * Disable interrupts until a chipset driver is loaded for
+	 * this PCI device. Else unhandled display adapter interrupts
+	 * might freeze the CPU.
+	 */
+	pci_write_config(dev, PCIR_COMMAND, config | PCIM_CMD_INTxDIS, 2);
+
 	/* This video card is the boot display: record its unit number. */
 	vga_pci_default_unit = unit;
 	device_set_flags(dev, 1);