lguest: stop using KVM hypercall mechanism
This is a partial revert of 4cd8b5e2a159 "lguest: use KVM hypercalls";
we revert to using (just as questionable but more reliable) int $15 for
hypercalls. I didn't revert the register mapping, so we still use the
same calling convention as kvm.
KVM in more recent incarnations stopped injecting a fault when a guest
tried to use the VMCALL instruction from ring 1, so lguest under kvm
fails to make hypercalls. It was nice to share code with our KVM
cousins, but this was overreach.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Matias Zabaljauregui <zabaljauregui@gmail.com>
Cc: Avi Kivity <avi@redhat.com>
diff --git a/arch/x86/lguest/boot.c b/arch/x86/lguest/boot.c
index 7e59dc1..2bdf628 100644
--- a/arch/x86/lguest/boot.c
+++ b/arch/x86/lguest/boot.c
@@ -115,7 +115,7 @@
local_irq_save(flags);
if (lguest_data.hcall_status[next_call] != 0xFF) {
/* Table full, so do normal hcall which will flush table. */
- kvm_hypercall4(call, arg1, arg2, arg3, arg4);
+ hcall(call, arg1, arg2, arg3, arg4);
} else {
lguest_data.hcalls[next_call].arg0 = call;
lguest_data.hcalls[next_call].arg1 = arg1;
@@ -145,46 +145,45 @@
* So, when we're in lazy mode, we call async_hcall() to store the call for
* future processing:
*/
-static void lazy_hcall1(unsigned long call,
- unsigned long arg1)
+static void lazy_hcall1(unsigned long call, unsigned long arg1)
{
if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_NONE)
- kvm_hypercall1(call, arg1);
+ hcall(call, arg1, 0, 0, 0);
else
async_hcall(call, arg1, 0, 0, 0);
}
/* You can imagine what lazy_hcall2, 3 and 4 look like. :*/
static void lazy_hcall2(unsigned long call,
- unsigned long arg1,
- unsigned long arg2)
+ unsigned long arg1,
+ unsigned long arg2)
{
if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_NONE)
- kvm_hypercall2(call, arg1, arg2);
+ hcall(call, arg1, arg2, 0, 0);
else
async_hcall(call, arg1, arg2, 0, 0);
}
static void lazy_hcall3(unsigned long call,
- unsigned long arg1,
- unsigned long arg2,
- unsigned long arg3)
+ unsigned long arg1,
+ unsigned long arg2,
+ unsigned long arg3)
{
if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_NONE)
- kvm_hypercall3(call, arg1, arg2, arg3);
+ hcall(call, arg1, arg2, arg3, 0);
else
async_hcall(call, arg1, arg2, arg3, 0);
}
#ifdef CONFIG_X86_PAE
static void lazy_hcall4(unsigned long call,
- unsigned long arg1,
- unsigned long arg2,
- unsigned long arg3,
- unsigned long arg4)
+ unsigned long arg1,
+ unsigned long arg2,
+ unsigned long arg3,
+ unsigned long arg4)
{
if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_NONE)
- kvm_hypercall4(call, arg1, arg2, arg3, arg4);
+ hcall(call, arg1, arg2, arg3, arg4);
else
async_hcall(call, arg1, arg2, arg3, arg4);
}
@@ -196,13 +195,13 @@
:*/
static void lguest_leave_lazy_mmu_mode(void)
{
- kvm_hypercall0(LHCALL_FLUSH_ASYNC);
+ hcall(LHCALL_FLUSH_ASYNC, 0, 0, 0, 0);
paravirt_leave_lazy_mmu();
}
static void lguest_end_context_switch(struct task_struct *next)
{
- kvm_hypercall0(LHCALL_FLUSH_ASYNC);
+ hcall(LHCALL_FLUSH_ASYNC, 0, 0, 0, 0);
paravirt_end_context_switch(next);
}
@@ -286,7 +285,7 @@
/* Keep the local copy up to date. */
native_write_idt_entry(dt, entrynum, g);
/* Tell Host about this new entry. */
- kvm_hypercall3(LHCALL_LOAD_IDT_ENTRY, entrynum, desc[0], desc[1]);
+ hcall(LHCALL_LOAD_IDT_ENTRY, entrynum, desc[0], desc[1], 0);
}
/*
@@ -300,7 +299,7 @@
struct desc_struct *idt = (void *)desc->address;
for (i = 0; i < (desc->size+1)/8; i++)
- kvm_hypercall3(LHCALL_LOAD_IDT_ENTRY, i, idt[i].a, idt[i].b);
+ hcall(LHCALL_LOAD_IDT_ENTRY, i, idt[i].a, idt[i].b, 0);
}
/*
@@ -321,7 +320,7 @@
struct desc_struct *gdt = (void *)desc->address;
for (i = 0; i < (desc->size+1)/8; i++)
- kvm_hypercall3(LHCALL_LOAD_GDT_ENTRY, i, gdt[i].a, gdt[i].b);
+ hcall(LHCALL_LOAD_GDT_ENTRY, i, gdt[i].a, gdt[i].b, 0);
}
/*
@@ -334,8 +333,8 @@
{
native_write_gdt_entry(dt, entrynum, desc, type);
/* Tell Host about this new entry. */
- kvm_hypercall3(LHCALL_LOAD_GDT_ENTRY, entrynum,
- dt[entrynum].a, dt[entrynum].b);
+ hcall(LHCALL_LOAD_GDT_ENTRY, entrynum,
+ dt[entrynum].a, dt[entrynum].b, 0);
}
/*
@@ -931,7 +930,7 @@
}
/* Please wake us this far in the future. */
- kvm_hypercall1(LHCALL_SET_CLOCKEVENT, delta);
+ hcall(LHCALL_SET_CLOCKEVENT, delta, 0, 0, 0);
return 0;
}
@@ -942,7 +941,7 @@
case CLOCK_EVT_MODE_UNUSED:
case CLOCK_EVT_MODE_SHUTDOWN:
/* A 0 argument shuts the clock down. */
- kvm_hypercall0(LHCALL_SET_CLOCKEVENT);
+ hcall(LHCALL_SET_CLOCKEVENT, 0, 0, 0, 0);
break;
case CLOCK_EVT_MODE_ONESHOT:
/* This is what we expect. */
@@ -1100,7 +1099,7 @@
/* STOP! Until an interrupt comes in. */
static void lguest_safe_halt(void)
{
- kvm_hypercall0(LHCALL_HALT);
+ hcall(LHCALL_HALT, 0, 0, 0, 0);
}
/*
@@ -1112,8 +1111,8 @@
*/
static void lguest_power_off(void)
{
- kvm_hypercall2(LHCALL_SHUTDOWN, __pa("Power down"),
- LGUEST_SHUTDOWN_POWEROFF);
+ hcall(LHCALL_SHUTDOWN, __pa("Power down"),
+ LGUEST_SHUTDOWN_POWEROFF, 0, 0);
}
/*
@@ -1123,7 +1122,7 @@
*/
static int lguest_panic(struct notifier_block *nb, unsigned long l, void *p)
{
- kvm_hypercall2(LHCALL_SHUTDOWN, __pa(p), LGUEST_SHUTDOWN_POWEROFF);
+ hcall(LHCALL_SHUTDOWN, __pa(p), LGUEST_SHUTDOWN_POWEROFF, 0, 0);
/* The hcall won't return, but to keep gcc happy, we're "done". */
return NOTIFY_DONE;
}
@@ -1162,7 +1161,7 @@
len = sizeof(scratch) - 1;
scratch[len] = '\0';
memcpy(scratch, buf, len);
- kvm_hypercall1(LHCALL_NOTIFY, __pa(scratch));
+ hcall(LHCALL_NOTIFY, __pa(scratch), 0, 0, 0);
/* This routine returns the number of bytes actually written. */
return len;
@@ -1174,7 +1173,7 @@
*/
static void lguest_restart(char *reason)
{
- kvm_hypercall2(LHCALL_SHUTDOWN, __pa(reason), LGUEST_SHUTDOWN_RESTART);
+ hcall(LHCALL_SHUTDOWN, __pa(reason), LGUEST_SHUTDOWN_RESTART, 0, 0);
}
/*G:050