1 files changed, 148 insertions, 160 deletions

diff --git a/arch/x86/include/asm/xen/hypercall.h b/arch/x86/include/asm/xen/hypercall.h
index ef05bea7010d..a16d4631547c 100644
--- a/arch/x86/include/asm/xen/hypercall.h
+++ b/arch/x86/include/asm/xen/hypercall.h
@@ -38,11 +38,13 @@
 #include <linux/errno.h>
 #include <linux/string.h>
 #include <linux/types.h>
+#include <linux/pgtable.h>
+#include <linux/instrumentation.h>
 
 #include <trace/events/xen.h>
 
+#include <asm/alternative.h>
 #include <asm/page.h>
-#include <asm/pgtable.h>
 #include <asm/smap.h>
 #include <asm/nospec-branch.h>
 
@@ -82,15 +84,25 @@ struct xen_dm_op_buf;
  *     - clobber the rest
  *
  * The result certainly isn't pretty, and it really shows up cpp's
- * weakness as as macro language.  Sorry.  (But let's just give thanks
+ * weakness as a macro language.  Sorry.  (But let's just give thanks
  * there aren't more than 5 arguments...)
  */
 
-extern struct { char _entry[32]; } hypercall_page[];
+void xen_hypercall_func(void);
+DECLARE_STATIC_CALL(xen_hypercall, xen_hypercall_func);
 
-#define __HYPERCALL		"call hypercall_page+%c[offset]"
-#define __HYPERCALL_ENTRY(x)						\
-	[offset] "i" (__HYPERVISOR_##x * sizeof(hypercall_page[0]))
+#ifdef MODULE
+#define __ADDRESSABLE_xen_hypercall
+#else
+#define __ADDRESSABLE_xen_hypercall \
+	__stringify(.global STATIC_CALL_KEY(xen_hypercall);)
+#endif
+
+#define __HYPERCALL					\
+	__ADDRESSABLE_xen_hypercall			\
+	__stringify(call STATIC_CALL_TRAMP(xen_hypercall))
+
+#define __HYPERCALL_ENTRY(x)	"a" (x)
 
 #ifdef CONFIG_X86_32
 #define __HYPERCALL_RETREG	"eax"
@@ -148,7 +160,7 @@ extern struct { char _entry[32]; } hypercall_page[];
 	__HYPERCALL_0ARG();						\
 	asm volatile (__HYPERCALL					\
 		      : __HYPERCALL_0PARAM				\
-		      : __HYPERCALL_ENTRY(name)				\
+		      : __HYPERCALL_ENTRY(__HYPERVISOR_ ## name)	\
 		      : __HYPERCALL_CLOBBER0);				\
 	(type)__res;							\
 })
@@ -159,7 +171,7 @@ extern struct { char _entry[32]; } hypercall_page[];
 	__HYPERCALL_1ARG(a1);						\
 	asm volatile (__HYPERCALL					\
 		      : __HYPERCALL_1PARAM				\
-		      : __HYPERCALL_ENTRY(name)				\
+		      : __HYPERCALL_ENTRY(__HYPERVISOR_ ## name)	\
 		      : __HYPERCALL_CLOBBER1);				\
 	(type)__res;							\
 })
@@ -170,7 +182,7 @@ extern struct { char _entry[32]; } hypercall_page[];
 	__HYPERCALL_2ARG(a1, a2);					\
 	asm volatile (__HYPERCALL					\
 		      : __HYPERCALL_2PARAM				\
-		      : __HYPERCALL_ENTRY(name)				\
+		      : __HYPERCALL_ENTRY(__HYPERVISOR_ ## name)	\
 		      : __HYPERCALL_CLOBBER2);				\
 	(type)__res;							\
 })
@@ -181,7 +193,7 @@ extern struct { char _entry[32]; } hypercall_page[];
 	__HYPERCALL_3ARG(a1, a2, a3);					\
 	asm volatile (__HYPERCALL					\
 		      : __HYPERCALL_3PARAM				\
-		      : __HYPERCALL_ENTRY(name)				\
+		      : __HYPERCALL_ENTRY(__HYPERVISOR_ ## name)	\
 		      : __HYPERCALL_CLOBBER3);				\
 	(type)__res;							\
 })
@@ -192,7 +204,7 @@ extern struct { char _entry[32]; } hypercall_page[];
 	__HYPERCALL_4ARG(a1, a2, a3, a4);				\
 	asm volatile (__HYPERCALL					\
 		      : __HYPERCALL_4PARAM				\
-		      : __HYPERCALL_ENTRY(name)				\
+		      : __HYPERCALL_ENTRY(__HYPERVISOR_ ## name)	\
 		      : __HYPERCALL_CLOBBER4);				\
 	(type)__res;							\
 })
@@ -206,14 +218,28 @@ xen_single_call(unsigned int call,
 	__HYPERCALL_DECLS;
 	__HYPERCALL_5ARG(a1, a2, a3, a4, a5);
 
-	asm volatile(CALL_NOSPEC
+	asm volatile(__HYPERCALL
 		     : __HYPERCALL_5PARAM
-		     : [thunk_target] "a" (&hypercall_page[call])
+		     : __HYPERCALL_ENTRY(call)
 		     : __HYPERCALL_CLOBBER5);
 
 	return (long)__res;
 }
 
+static __always_inline void __xen_stac(void)
+{
+	/*
+	 * Suppress objtool seeing the STAC/CLAC and getting confused about it
+	 * calling random code with AC=1.
+	 */
+	asm volatile(ASM_STAC_UNSAFE ::: "memory", "flags");
+}
+
+static __always_inline void __xen_clac(void)
+{
+	asm volatile(ASM_CLAC_UNSAFE ::: "memory", "flags");
+}
+
 static inline long
 privcmd_call(unsigned int call,
 	     unsigned long a1, unsigned long a2,
@@ -222,13 +248,14 @@ privcmd_call(unsigned int call,
 {
 	long res;
 
-	stac();
+	__xen_stac();
 	res = xen_single_call(call, a1, a2, a3, a4, a5);
-	clac();
+	__xen_clac();
 
 	return res;
 }
 
+#ifdef CONFIG_XEN_PV
 static inline int
 HYPERVISOR_set_trap_table(struct trap_info *table)
 {
@@ -261,7 +288,108 @@ HYPERVISOR_callback_op(int cmd, void *arg)
 	return _hypercall2(int, callback_op, cmd, arg);
 }
 
+static __always_inline int
+HYPERVISOR_set_debugreg(int reg, unsigned long value)
+{
+	return _hypercall2(int, set_debugreg, reg, value);
+}
+
+static __always_inline unsigned long
+HYPERVISOR_get_debugreg(int reg)
+{
+	return _hypercall1(unsigned long, get_debugreg, reg);
+}
+
 static inline int
+HYPERVISOR_update_descriptor(u64 ma, u64 desc)
+{
+	return _hypercall2(int, update_descriptor, ma, desc);
+}
+
+static inline int
+HYPERVISOR_update_va_mapping(unsigned long va, pte_t new_val,
+			     unsigned long flags)
+{
+	return _hypercall3(int, update_va_mapping, va, new_val.pte, flags);
+}
+
+static inline int
+HYPERVISOR_set_segment_base(int reg, unsigned long value)
+{
+	return _hypercall2(int, set_segment_base, reg, value);
+}
+
+static inline void
+MULTI_fpu_taskswitch(struct multicall_entry *mcl, int set)
+{
+	mcl->op = __HYPERVISOR_fpu_taskswitch;
+	mcl->args[0] = set;
+
+	trace_xen_mc_entry(mcl, 1);
+}
+
+static inline void
+MULTI_update_va_mapping(struct multicall_entry *mcl, unsigned long va,
+			pte_t new_val, unsigned long flags)
+{
+	mcl->op = __HYPERVISOR_update_va_mapping;
+	mcl->args[0] = va;
+	mcl->args[1] = new_val.pte;
+	mcl->args[2] = flags;
+
+	trace_xen_mc_entry(mcl, 3);
+}
+
+static inline void
+MULTI_update_descriptor(struct multicall_entry *mcl, u64 maddr,
+			struct desc_struct desc)
+{
+	mcl->op = __HYPERVISOR_update_descriptor;
+	mcl->args[0] = maddr;
+	mcl->args[1] = *(unsigned long *)&desc;
+
+	trace_xen_mc_entry(mcl, 2);
+}
+
+static inline void
+MULTI_mmu_update(struct multicall_entry *mcl, struct mmu_update *req,
+		 int count, int *success_count, domid_t domid)
+{
+	mcl->op = __HYPERVISOR_mmu_update;
+	mcl->args[0] = (unsigned long)req;
+	mcl->args[1] = count;
+	mcl->args[2] = (unsigned long)success_count;
+	mcl->args[3] = domid;
+
+	trace_xen_mc_entry(mcl, 4);
+}
+
+static inline void
+MULTI_mmuext_op(struct multicall_entry *mcl, struct mmuext_op *op, int count,
+		int *success_count, domid_t domid)
+{
+	mcl->op = __HYPERVISOR_mmuext_op;
+	mcl->args[0] = (unsigned long)op;
+	mcl->args[1] = count;
+	mcl->args[2] = (unsigned long)success_count;
+	mcl->args[3] = domid;
+
+	trace_xen_mc_entry(mcl, 4);
+}
+
+static inline void
+MULTI_stack_switch(struct multicall_entry *mcl,
+		   unsigned long ss, unsigned long esp)
+{
+	mcl->op = __HYPERVISOR_stack_switch;
+	mcl->args[0] = ss;
+	mcl->args[1] = esp;
+
+	trace_xen_mc_entry(mcl, 2);
+}
+#endif
+
+static __always_inline int
 HYPERVISOR_sched_op(int cmd, void *arg)
 {
 	return _hypercall2(int, sched_op, cmd, arg);
@@ -289,26 +417,6 @@ HYPERVISOR_platform_op(struct xen_platform_op *op)
 	return _hypercall1(int, platform_op, op);
 }
 
-static inline int
-HYPERVISOR_set_debugreg(int reg, unsigned long value)
-{
-	return _hypercall2(int, set_debugreg, reg, value);
-}
-
-static inline unsigned long
-HYPERVISOR_get_debugreg(int reg)
-{
-	return _hypercall1(unsigned long, get_debugreg, reg);
-}
-
-static inline int
-HYPERVISOR_update_descriptor(u64 ma, u64 desc)
-{
-	if (sizeof(u64) == sizeof(long))
-		return _hypercall2(int, update_descriptor, ma, desc);
-	return _hypercall4(int, update_descriptor, ma, ma>>32, desc, desc>>32);
-}
-
 static inline long
 HYPERVISOR_memory_op(unsigned int cmd, void *arg)
 {
@@ -322,28 +430,12 @@ HYPERVISOR_multicall(void *call_list, uint32_t nr_calls)
 }
 
 static inline int
-HYPERVISOR_update_va_mapping(unsigned long va, pte_t new_val,
-			     unsigned long flags)
-{
-	if (sizeof(new_val) == sizeof(long))
-		return _hypercall3(int, update_va_mapping, va,
-				   new_val.pte, flags);
-	else
-		return _hypercall4(int, update_va_mapping, va,
-				   new_val.pte, new_val.pte >> 32, flags);
-}
-extern int __must_check xen_event_channel_op_compat(int, void *);
-
-static inline int
 HYPERVISOR_event_channel_op(int cmd, void *arg)
 {
-	int rc = _hypercall2(int, event_channel_op, cmd, arg);
-	if (unlikely(rc == -ENOSYS))
-		rc = xen_event_channel_op_compat(cmd, arg);
-	return rc;
+	return _hypercall2(int, event_channel_op, cmd, arg);
 }
 
-static inline int
+static __always_inline int
 HYPERVISOR_xen_version(int cmd, void *arg)
 {
 	return _hypercall2(int, xen_version, cmd, arg);
@@ -355,15 +447,10 @@ HYPERVISOR_console_io(int cmd, int count, char *str)
 	return _hypercall3(int, console_io, cmd, count, str);
 }
 
-extern int __must_check xen_physdev_op_compat(int, void *);
-
 static inline int
 HYPERVISOR_physdev_op(int cmd, void *arg)
 {
-	int rc = _hypercall2(int, physdev_op, cmd, arg);
-	if (unlikely(rc == -ENOSYS))
-		rc = xen_physdev_op_compat(cmd, arg);
-	return rc;
+	return _hypercall2(int, physdev_op, cmd, arg);
 }
 
 static inline int
@@ -384,14 +471,6 @@ HYPERVISOR_vcpu_op(int cmd, int vcpuid, void *extra_args)
 	return _hypercall3(int, vcpu_op, cmd, vcpuid, extra_args);
 }
 
-#ifdef CONFIG_X86_64
-static inline int
-HYPERVISOR_set_segment_base(int reg, unsigned long value)
-{
-	return _hypercall2(int, set_segment_base, reg, value);
-}
-#endif
-
 static inline int
 HYPERVISOR_suspend(unsigned long start_info_mfn)
 {
@@ -413,13 +492,6 @@ HYPERVISOR_hvm_op(int op, void *arg)
 }
 
 static inline int
-HYPERVISOR_tmem_op(
-	struct tmem_op *op)
-{
-	return _hypercall1(int, tmem_op, op);
-}
-
-static inline int
 HYPERVISOR_xenpmu_op(unsigned int op, void *arg)
 {
 	return _hypercall2(int, xenpmu_op, op, arg);
@@ -430,94 +502,10 @@ HYPERVISOR_dm_op(
 	domid_t dom, unsigned int nr_bufs, struct xen_dm_op_buf *bufs)
 {
 	int ret;
-	stac();
+	__xen_stac();
 	ret = _hypercall3(int, dm_op, dom, nr_bufs, bufs);
-	clac();
+	__xen_clac();
 	return ret;
 }
 
-static inline void
-MULTI_fpu_taskswitch(struct multicall_entry *mcl, int set)
-{
-	mcl->op = __HYPERVISOR_fpu_taskswitch;
-	mcl->args[0] = set;
-
-	trace_xen_mc_entry(mcl, 1);
-}
-
-static inline void
-MULTI_update_va_mapping(struct multicall_entry *mcl, unsigned long va,
-			pte_t new_val, unsigned long flags)
-{
-	mcl->op = __HYPERVISOR_update_va_mapping;
-	mcl->args[0] = va;
-	if (sizeof(new_val) == sizeof(long)) {
-		mcl->args[1] = new_val.pte;
-		mcl->args[2] = flags;
-	} else {
-		mcl->args[1] = new_val.pte;
-		mcl->args[2] = new_val.pte >> 32;
-		mcl->args[3] = flags;
-	}
-
-	trace_xen_mc_entry(mcl, sizeof(new_val) == sizeof(long) ? 3 : 4);
-}
-
-static inline void
-MULTI_update_descriptor(struct multicall_entry *mcl, u64 maddr,
-			struct desc_struct desc)
-{
-	mcl->op = __HYPERVISOR_update_descriptor;
-	if (sizeof(maddr) == sizeof(long)) {
-		mcl->args[0] = maddr;
-		mcl->args[1] = *(unsigned long *)&desc;
-	} else {
-		u32 *p = (u32 *)&desc;
-
-		mcl->args[0] = maddr;
-		mcl->args[1] = maddr >> 32;
-		mcl->args[2] = *p++;
-		mcl->args[3] = *p;
-	}
-
-	trace_xen_mc_entry(mcl, sizeof(maddr) == sizeof(long) ? 2 : 4);
-}
-
-static inline void
-MULTI_mmu_update(struct multicall_entry *mcl, struct mmu_update *req,
-		 int count, int *success_count, domid_t domid)
-{
-	mcl->op = __HYPERVISOR_mmu_update;
-	mcl->args[0] = (unsigned long)req;
-	mcl->args[1] = count;
-	mcl->args[2] = (unsigned long)success_count;
-	mcl->args[3] = domid;
-
-	trace_xen_mc_entry(mcl, 4);
-}
-
-static inline void
-MULTI_mmuext_op(struct multicall_entry *mcl, struct mmuext_op *op, int count,
-		int *success_count, domid_t domid)
-{
-	mcl->op = __HYPERVISOR_mmuext_op;
-	mcl->args[0] = (unsigned long)op;
-	mcl->args[1] = count;
-	mcl->args[2] = (unsigned long)success_count;
-	mcl->args[3] = domid;
-
-	trace_xen_mc_entry(mcl, 4);
-}
-
-static inline void
-MULTI_stack_switch(struct multicall_entry *mcl,
-		   unsigned long ss, unsigned long esp)
-{
-	mcl->op = __HYPERVISOR_stack_switch;
-	mcl->args[0] = ss;
-	mcl->args[1] = esp;
-
-	trace_xen_mc_entry(mcl, 2);
-}
-
 #endif /* _ASM_X86_XEN_HYPERCALL_H */