6 files changed, 82 insertions, 23 deletions

diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S
index a52703864a16..e4c9710cae52 100644
--- a/arch/x86/kernel/entry_64.S
+++ b/arch/x86/kernel/entry_64.S
@@ -1140,7 +1140,7 @@ ENTRY(native_load_gs_index)
 	CFI_STARTPROC
 	pushf
 	CFI_ADJUST_CFA_OFFSET 8
-	DISABLE_INTERRUPTS(CLBR_ANY | ~(CLBR_RDI))
+	DISABLE_INTERRUPTS(CLBR_ANY & ~CLBR_RDI)
 	SWAPGS
 gs_change:
 	movl %edi,%gs
diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c
index e4c8fb608873..cea11c8e3049 100644
--- a/arch/x86/kernel/paravirt.c
+++ b/arch/x86/kernel/paravirt.c
@@ -44,6 +44,17 @@ void _paravirt_nop(void)
 {
 }
 
+/* identity function, which can be inlined */
+u32 _paravirt_ident_32(u32 x)
+{
+	return x;
+}
+
+u64 _paravirt_ident_64(u64 x)
+{
+	return x;
+}
+
 static void __init default_banner(void)
 {
 	printk(KERN_INFO "Booting paravirtualized kernel on %s\n",
@@ -138,9 +149,16 @@ unsigned paravirt_patch_default(u8 type, u16 clobbers, void *insnbuf,
 	if (opfunc == NULL)
 		/* If there's no function, patch it with a ud2a (BUG) */
 		ret = paravirt_patch_insns(insnbuf, len, ud2a, ud2a+sizeof(ud2a));
-	else if (opfunc == paravirt_nop)
+	else if (opfunc == _paravirt_nop)
 		/* If the operation is a nop, then nop the callsite */
 		ret = paravirt_patch_nop();
+
+	/* identity functions just return their single argument */
+	else if (opfunc == _paravirt_ident_32)
+		ret = paravirt_patch_ident_32(insnbuf, len);
+	else if (opfunc == _paravirt_ident_64)
+		ret = paravirt_patch_ident_64(insnbuf, len);
+
 	else if (type == PARAVIRT_PATCH(pv_cpu_ops.iret) ||
 		 type == PARAVIRT_PATCH(pv_cpu_ops.irq_enable_sysexit) ||
 		 type == PARAVIRT_PATCH(pv_cpu_ops.usergs_sysret32) ||
@@ -292,10 +310,10 @@ struct pv_time_ops pv_time_ops = {
 
 struct pv_irq_ops pv_irq_ops = {
 	.init_IRQ = native_init_IRQ,
-	.save_fl = native_save_fl,
-	.restore_fl = native_restore_fl,
-	.irq_disable = native_irq_disable,
-	.irq_enable = native_irq_enable,
+	.save_fl = __PV_IS_CALLEE_SAVE(native_save_fl),
+	.restore_fl = __PV_IS_CALLEE_SAVE(native_restore_fl),
+	.irq_disable = __PV_IS_CALLEE_SAVE(native_irq_disable),
+	.irq_enable = __PV_IS_CALLEE_SAVE(native_irq_enable),
 	.safe_halt = native_safe_halt,
 	.halt = native_halt,
 #ifdef CONFIG_X86_64
@@ -373,6 +391,14 @@ struct pv_apic_ops pv_apic_ops = {
 #endif
 };
 
+#if defined(CONFIG_X86_32) && !defined(CONFIG_X86_PAE)
+/* 32-bit pagetable entries */
+#define PTE_IDENT	__PV_IS_CALLEE_SAVE(_paravirt_ident_32)
+#else
+/* 64-bit pagetable entries */
+#define PTE_IDENT	__PV_IS_CALLEE_SAVE(_paravirt_ident_64)
+#endif
+
 struct pv_mmu_ops pv_mmu_ops = {
 #ifndef CONFIG_X86_64
 	.pagetable_setup_start = native_pagetable_setup_start,
@@ -424,22 +450,23 @@ struct pv_mmu_ops pv_mmu_ops = {
 	.pmd_clear = native_pmd_clear,
 #endif
 	.set_pud = native_set_pud,
-	.pmd_val = native_pmd_val,
-	.make_pmd = native_make_pmd,
+
+	.pmd_val = PTE_IDENT,
+	.make_pmd = PTE_IDENT,
 
 #if PAGETABLE_LEVELS == 4
-	.pud_val = native_pud_val,
-	.make_pud = native_make_pud,
+	.pud_val = PTE_IDENT,
+	.make_pud = PTE_IDENT,
+
 	.set_pgd = native_set_pgd,
 #endif
 #endif /* PAGETABLE_LEVELS >= 3 */
 
-	.pte_val = native_pte_val,
-	.pte_flags = native_pte_flags,
-	.pgd_val = native_pgd_val,
+	.pte_val = PTE_IDENT,
+	.pgd_val = PTE_IDENT,
 
-	.make_pte = native_make_pte,
-	.make_pgd = native_make_pgd,
+	.make_pte = PTE_IDENT,
+	.make_pgd = PTE_IDENT,
 
 	.dup_mmap = paravirt_nop,
 	.exit_mmap = paravirt_nop,
diff --git a/arch/x86/kernel/paravirt_patch_32.c b/arch/x86/kernel/paravirt_patch_32.c
index 9fe644f4861d..d9f32e6d6ab6 100644
--- a/arch/x86/kernel/paravirt_patch_32.c
+++ b/arch/x86/kernel/paravirt_patch_32.c
@@ -12,6 +12,18 @@ DEF_NATIVE(pv_mmu_ops, read_cr3, "mov %cr3, %eax");
 DEF_NATIVE(pv_cpu_ops, clts, "clts");
 DEF_NATIVE(pv_cpu_ops, read_tsc, "rdtsc");
 
+unsigned paravirt_patch_ident_32(void *insnbuf, unsigned len)
+{
+	/* arg in %eax, return in %eax */
+	return 0;
+}
+
+unsigned paravirt_patch_ident_64(void *insnbuf, unsigned len)
+{
+	/* arg in %edx:%eax, return in %edx:%eax */
+	return 0;
+}
+
 unsigned native_patch(u8 type, u16 clobbers, void *ibuf,
 		      unsigned long addr, unsigned len)
 {
diff --git a/arch/x86/kernel/paravirt_patch_64.c b/arch/x86/kernel/paravirt_patch_64.c
index 061d01df9ae6..3f08f34f93eb 100644
--- a/arch/x86/kernel/paravirt_patch_64.c
+++ b/arch/x86/kernel/paravirt_patch_64.c
@@ -19,6 +19,21 @@ DEF_NATIVE(pv_cpu_ops, usergs_sysret64, "swapgs; sysretq");
 DEF_NATIVE(pv_cpu_ops, usergs_sysret32, "swapgs; sysretl");
 DEF_NATIVE(pv_cpu_ops, swapgs, "swapgs");
 
+DEF_NATIVE(, mov32, "mov %edi, %eax");
+DEF_NATIVE(, mov64, "mov %rdi, %rax");
+
+unsigned paravirt_patch_ident_32(void *insnbuf, unsigned len)
+{
+	return paravirt_patch_insns(insnbuf, len,
+				    start__mov32, end__mov32);
+}
+
+unsigned paravirt_patch_ident_64(void *insnbuf, unsigned len)
+{
+	return paravirt_patch_insns(insnbuf, len,
+				    start__mov64, end__mov64);
+}
+
 unsigned native_patch(u8 type, u16 clobbers, void *ibuf,
 		      unsigned long addr, unsigned len)
 {
diff --git a/arch/x86/kernel/vmi_32.c b/arch/x86/kernel/vmi_32.c
index 1d3302cc2ddf..eb9e7347928e 100644
--- a/arch/x86/kernel/vmi_32.c
+++ b/arch/x86/kernel/vmi_32.c
@@ -670,10 +670,11 @@ static inline int __init activate_vmi(void)
 	para_fill(pv_mmu_ops.write_cr2, SetCR2);
 	para_fill(pv_mmu_ops.write_cr3, SetCR3);
 	para_fill(pv_cpu_ops.write_cr4, SetCR4);
-	para_fill(pv_irq_ops.save_fl, GetInterruptMask);
-	para_fill(pv_irq_ops.restore_fl, SetInterruptMask);
-	para_fill(pv_irq_ops.irq_disable, DisableInterrupts);
-	para_fill(pv_irq_ops.irq_enable, EnableInterrupts);
+
+	para_fill(pv_irq_ops.save_fl.func, GetInterruptMask);
+	para_fill(pv_irq_ops.restore_fl.func, SetInterruptMask);
+	para_fill(pv_irq_ops.irq_disable.func, DisableInterrupts);
+	para_fill(pv_irq_ops.irq_enable.func, EnableInterrupts);
 
 	para_fill(pv_cpu_ops.wbinvd, WBINVD);
 	para_fill(pv_cpu_ops.read_tsc, RDTSC);
diff --git a/arch/x86/kernel/vsmp_64.c b/arch/x86/kernel/vsmp_64.c
index a688f3bfaec2..c609205df594 100644
--- a/arch/x86/kernel/vsmp_64.c
+++ b/arch/x86/kernel/vsmp_64.c
@@ -37,6 +37,7 @@ static unsigned long vsmp_save_fl(void)
 		flags &= ~X86_EFLAGS_IF;
 	return flags;
 }
+PV_CALLEE_SAVE_REGS_THUNK(vsmp_save_fl);
 
 static void vsmp_restore_fl(unsigned long flags)
 {
@@ -46,6 +47,7 @@ static void vsmp_restore_fl(unsigned long flags)
 		flags |= X86_EFLAGS_AC;
 	native_restore_fl(flags);
 }
+PV_CALLEE_SAVE_REGS_THUNK(vsmp_restore_fl);
 
 static void vsmp_irq_disable(void)
 {
@@ -53,6 +55,7 @@ static void vsmp_irq_disable(void)
 
 	native_restore_fl((flags & ~X86_EFLAGS_IF) | X86_EFLAGS_AC);
 }
+PV_CALLEE_SAVE_REGS_THUNK(vsmp_irq_disable);
 
 static void vsmp_irq_enable(void)
 {
@@ -60,6 +63,7 @@ static void vsmp_irq_enable(void)
 
 	native_restore_fl((flags | X86_EFLAGS_IF) & (~X86_EFLAGS_AC));
 }
+PV_CALLEE_SAVE_REGS_THUNK(vsmp_irq_enable);
 
 static unsigned __init_or_module vsmp_patch(u8 type, u16 clobbers, void *ibuf,
 				  unsigned long addr, unsigned len)
@@ -90,10 +94,10 @@ static void __init set_vsmp_pv_ops(void)
 	       cap, ctl);
 	if (cap & ctl & (1 << 4)) {
 		/* Setup irq ops and turn on vSMP  IRQ fastpath handling */
-		pv_irq_ops.irq_disable = vsmp_irq_disable;
-		pv_irq_ops.irq_enable  = vsmp_irq_enable;
-		pv_irq_ops.save_fl  = vsmp_save_fl;
-		pv_irq_ops.restore_fl  = vsmp_restore_fl;
+		pv_irq_ops.irq_disable = PV_CALLEE_SAVE(vsmp_irq_disable);
+		pv_irq_ops.irq_enable  = PV_CALLEE_SAVE(vsmp_irq_enable);
+		pv_irq_ops.save_fl  = PV_CALLEE_SAVE(vsmp_save_fl);
+		pv_irq_ops.restore_fl  = PV_CALLEE_SAVE(vsmp_restore_fl);
 		pv_init_ops.patch = vsmp_patch;
 
 		ctl &= ~(1 << 4);