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Diffstat (limited to 'arch/x86/xen/enlighten.c')
-rw-r--r--arch/x86/xen/enlighten.c65
1 files changed, 57 insertions, 8 deletions
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index f09e8c36ee80..0a1700a2be9c 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -20,6 +20,7 @@
#include <linux/delay.h>
#include <linux/start_kernel.h>
#include <linux/sched.h>
+#include <linux/kprobes.h>
#include <linux/bootmem.h>
#include <linux/module.h>
#include <linux/mm.h>
@@ -44,6 +45,7 @@
#include <asm/processor.h>
#include <asm/proto.h>
#include <asm/msr-index.h>
+#include <asm/traps.h>
#include <asm/setup.h>
#include <asm/desc.h>
#include <asm/pgtable.h>
@@ -240,10 +242,10 @@ static unsigned long xen_get_debugreg(int reg)
return HYPERVISOR_get_debugreg(reg);
}
-void xen_leave_lazy(void)
+static void xen_end_context_switch(struct task_struct *next)
{
- paravirt_leave_lazy(paravirt_get_lazy_mode());
xen_mc_flush();
+ paravirt_end_context_switch(next);
}
static unsigned long xen_store_tr(void)
@@ -428,11 +430,44 @@ static void xen_write_ldt_entry(struct desc_struct *dt, int entrynum,
static int cvt_gate_to_trap(int vector, const gate_desc *val,
struct trap_info *info)
{
+ unsigned long addr;
+
if (val->type != GATE_TRAP && val->type != GATE_INTERRUPT)
return 0;
info->vector = vector;
- info->address = gate_offset(*val);
+
+ addr = gate_offset(*val);
+#ifdef CONFIG_X86_64
+ /*
+ * Look for known traps using IST, and substitute them
+ * appropriately. The debugger ones are the only ones we care
+ * about. Xen will handle faults like double_fault and
+ * machine_check, so we should never see them. Warn if
+ * there's an unexpected IST-using fault handler.
+ */
+ if (addr == (unsigned long)debug)
+ addr = (unsigned long)xen_debug;
+ else if (addr == (unsigned long)int3)
+ addr = (unsigned long)xen_int3;
+ else if (addr == (unsigned long)stack_segment)
+ addr = (unsigned long)xen_stack_segment;
+ else if (addr == (unsigned long)double_fault ||
+ addr == (unsigned long)nmi) {
+ /* Don't need to handle these */
+ return 0;
+#ifdef CONFIG_X86_MCE
+ } else if (addr == (unsigned long)machine_check) {
+ return 0;
+#endif
+ } else {
+ /* Some other trap using IST? */
+ if (WARN_ON(val->ist != 0))
+ return 0;
+ }
+#endif /* CONFIG_X86_64 */
+ info->address = addr;
+
info->cs = gate_segment(*val);
info->flags = val->dpl;
/* interrupt gates clear IF */
@@ -623,10 +658,26 @@ static void xen_clts(void)
xen_mc_issue(PARAVIRT_LAZY_CPU);
}
+static DEFINE_PER_CPU(unsigned long, xen_cr0_value);
+
+static unsigned long xen_read_cr0(void)
+{
+ unsigned long cr0 = percpu_read(xen_cr0_value);
+
+ if (unlikely(cr0 == 0)) {
+ cr0 = native_read_cr0();
+ percpu_write(xen_cr0_value, cr0);
+ }
+
+ return cr0;
+}
+
static void xen_write_cr0(unsigned long cr0)
{
struct multicall_space mcs;
+ percpu_write(xen_cr0_value, cr0);
+
/* Only pay attention to cr0.TS; everything else is
ignored. */
mcs = xen_mc_entry(0);
@@ -812,7 +863,7 @@ static const struct pv_cpu_ops xen_cpu_ops __initdata = {
.clts = xen_clts,
- .read_cr0 = native_read_cr0,
+ .read_cr0 = xen_read_cr0,
.write_cr0 = xen_write_cr0,
.read_cr4 = native_read_cr4,
@@ -860,10 +911,8 @@ static const struct pv_cpu_ops xen_cpu_ops __initdata = {
/* Xen takes care of %gs when switching to usermode for us */
.swapgs = paravirt_nop,
- .lazy_mode = {
- .enter = paravirt_enter_lazy_cpu,
- .leave = xen_leave_lazy,
- },
+ .start_context_switch = paravirt_start_context_switch,
+ .end_context_switch = xen_end_context_switch,
};
static const struct pv_apic_ops xen_apic_ops __initdata = {