xen/23782-x86-ioapic-clear-irr.patch
Charles Arnold 800917b5a2 - bnc#717650 - Unable to start VM
- Update to Xen 4.1.2_rc2 c/s 23152

- bnc#716695 - domUs using tap devices will not start
  updated multi-xvdp.patch

- Upstream patches from Jan
  23803-intel-pmu-models.patch
  23800-x86_64-guest-addr-range.patch
  23795-intel-ich10-quirk.patch
  23804-x86-IPI-counts.patch 

- bnc#706106 - Inconsistent reporting of VM names during migration
  xend-migration-domname-fix.patch

- bnc#712823 - L3:Xen guest does not start reliable when rebooted
  xend-vcpu-affinity-fix.patch

OBS-URL: https://build.opensuse.org/package/show/Virtualization/xen?expand=0&rev=143
2011-09-15 21:43:21 +00:00

74 lines
2.5 KiB
Diff

References: bnc#701686
# HG changeset patch
# User Jan Beulich <jbeulich@novell.com>
# Date 1314004270 -3600
# Node ID 25dfe53bb1898b3967ceb71a7eb60a8b760c25fb
# Parent 0849b0e59e2418e8215616df147f955b01b07577
x86/IO-APIC: clear remoteIRR in clear_IO_APIC_pin()
It was found that in a crash scenario, the remoteIRR bit in an IO-APIC
RTE could be left set, causing problems when bringing up a kdump
kernel. While this generally is most important to be taken care of in
the new kernel (which usually would be a native one), it still seems
desirable to also address this problem in Xen so that (a) the problem
doesn't bite Xen when used as a secondary emergency kernel and (b) an
attempt is being made to save un-fixed secondary kernels from running
into said problem.
Based on a Linux patch from suresh.b.siddha@intel.com.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Index: xen-4.1.2-testing/xen/arch/x86/io_apic.c
===================================================================
--- xen-4.1.2-testing.orig/xen/arch/x86/io_apic.c
+++ xen-4.1.2-testing/xen/arch/x86/io_apic.c
@@ -375,11 +375,46 @@ static void clear_IO_APIC_pin(unsigned i
return;
/*
+ * Make sure the entry is masked and re-read the contents to check
+ * if it is a level triggered pin and if the remoteIRR is set.
+ */
+ if (!entry.mask) {
+ entry.mask = 1;
+ __ioapic_write_entry(apic, pin, FALSE, entry);
+ }
+ entry = __ioapic_read_entry(apic, pin, TRUE);
+
+ if (entry.irr) {
+ /* Make sure the trigger mode is set to level. */
+ if (!entry.trigger) {
+ entry.trigger = 1;
+ __ioapic_write_entry(apic, pin, TRUE, entry);
+ }
+ if (mp_ioapics[apic].mpc_apicver >= 0x20)
+ io_apic_eoi(apic, entry.vector);
+ else {
+ /*
+ * Mechanism by which we clear remoteIRR in this case is by
+ * changing the trigger mode to edge and back to level.
+ */
+ entry.trigger = 0;
+ __ioapic_write_entry(apic, pin, TRUE, entry);
+ entry.trigger = 1;
+ __ioapic_write_entry(apic, pin, TRUE, entry);
+ }
+ }
+
+ /*
* Disable it in the IO-APIC irq-routing table:
*/
memset(&entry, 0, sizeof(entry));
entry.mask = 1;
__ioapic_write_entry(apic, pin, TRUE, entry);
+
+ entry = __ioapic_read_entry(apic, pin, TRUE);
+ if (entry.irr)
+ printk(KERN_ERR "IO-APIC%02x-%u: Unable to reset IRR\n",
+ IO_APIC_ID(apic), pin);
}
static void clear_IO_APIC (void)