Re: [PATCH 1/3] paravirt,xen: remove xen_patch()

2017-08-10 Thread Juergen Gross 
On 10/08/17 18:29, Peter Zijlstra wrote:
> On Thu, Aug 10, 2017 at 06:24:53PM +0200, Peter Zijlstra wrote:
>> -ENTRY(xen_irq_enable_direct)
>> -FRAME_BEGIN
>> -/* Unmask events */
>> -movb $0, PER_CPU_VAR(xen_vcpu_info) + XEN_vcpu_info_mask
>> -
>> -/*
>> - * Preempt here doesn't matter because that will deal with any
>> - * pending interrupts.  The pending check may end up being run
>> - * on the wrong CPU, but that doesn't hurt.
>> - */
>> -
>> -/* Test for pending */
>> -testb $0xff, PER_CPU_VAR(xen_vcpu_info) + XEN_vcpu_info_pending
>> -jz 1f
>> -
>> -2:  call check_events
>> -1:
>> -ENDPATCH(xen_irq_enable_direct)
>> -FRAME_END
>> -ret
>> -ENDPROC(xen_irq_enable_direct)
>> -RELOC(xen_irq_enable_direct, 2b+1)
> 
> Oh my bad, part of that is still used.
> 
> arch/x86/xen/enlighten_pv.c:pv_irq_ops.irq_enable = 
> __PV_IS_CALLEE_SAVE(xen_irq_enable_direct);
> 
> It just needs cleanups for the ENDPATCH and such.

Ah yes, of course.


Juergen

Re: [PATCH 1/3] paravirt,xen: remove xen_patch()

2017-08-10 Thread Juergen Gross 
On 10/08/17 18:29, Peter Zijlstra wrote:
> On Thu, Aug 10, 2017 at 06:24:53PM +0200, Peter Zijlstra wrote:
>> -ENTRY(xen_irq_enable_direct)
>> -FRAME_BEGIN
>> -/* Unmask events */
>> -movb $0, PER_CPU_VAR(xen_vcpu_info) + XEN_vcpu_info_mask
>> -
>> -/*
>> - * Preempt here doesn't matter because that will deal with any
>> - * pending interrupts.  The pending check may end up being run
>> - * on the wrong CPU, but that doesn't hurt.
>> - */
>> -
>> -/* Test for pending */
>> -testb $0xff, PER_CPU_VAR(xen_vcpu_info) + XEN_vcpu_info_pending
>> -jz 1f
>> -
>> -2:  call check_events
>> -1:
>> -ENDPATCH(xen_irq_enable_direct)
>> -FRAME_END
>> -ret
>> -ENDPROC(xen_irq_enable_direct)
>> -RELOC(xen_irq_enable_direct, 2b+1)
> 
> Oh my bad, part of that is still used.
> 
> arch/x86/xen/enlighten_pv.c:pv_irq_ops.irq_enable = 
> __PV_IS_CALLEE_SAVE(xen_irq_enable_direct);
> 
> It just needs cleanups for the ENDPATCH and such.

Ah yes, of course.


Juergen

Re: [PATCH 1/3] paravirt,xen: remove xen_patch()

2017-08-10 Thread Peter Zijlstra 
On Thu, Aug 10, 2017 at 06:24:53PM +0200, Peter Zijlstra wrote:
> -ENTRY(xen_irq_enable_direct)
> - FRAME_BEGIN
> - /* Unmask events */
> - movb $0, PER_CPU_VAR(xen_vcpu_info) + XEN_vcpu_info_mask
> -
> - /*
> -  * Preempt here doesn't matter because that will deal with any
> -  * pending interrupts.  The pending check may end up being run
> -  * on the wrong CPU, but that doesn't hurt.
> -  */
> -
> - /* Test for pending */
> - testb $0xff, PER_CPU_VAR(xen_vcpu_info) + XEN_vcpu_info_pending
> - jz 1f
> -
> -2:   call check_events
> -1:
> -ENDPATCH(xen_irq_enable_direct)
> - FRAME_END
> - ret
> - ENDPROC(xen_irq_enable_direct)
> - RELOC(xen_irq_enable_direct, 2b+1)

Oh my bad, part of that is still used.

arch/x86/xen/enlighten_pv.c:pv_irq_ops.irq_enable = 
__PV_IS_CALLEE_SAVE(xen_irq_enable_direct);

It just needs cleanups for the ENDPATCH and such.

Re: [PATCH 1/3] paravirt,xen: remove xen_patch()

2017-08-10 Thread Peter Zijlstra 
On Thu, Aug 10, 2017 at 06:24:53PM +0200, Peter Zijlstra wrote:
> -ENTRY(xen_irq_enable_direct)
> - FRAME_BEGIN
> - /* Unmask events */
> - movb $0, PER_CPU_VAR(xen_vcpu_info) + XEN_vcpu_info_mask
> -
> - /*
> -  * Preempt here doesn't matter because that will deal with any
> -  * pending interrupts.  The pending check may end up being run
> -  * on the wrong CPU, but that doesn't hurt.
> -  */
> -
> - /* Test for pending */
> - testb $0xff, PER_CPU_VAR(xen_vcpu_info) + XEN_vcpu_info_pending
> - jz 1f
> -
> -2:   call check_events
> -1:
> -ENDPATCH(xen_irq_enable_direct)
> - FRAME_END
> - ret
> - ENDPROC(xen_irq_enable_direct)
> - RELOC(xen_irq_enable_direct, 2b+1)

Oh my bad, part of that is still used.

arch/x86/xen/enlighten_pv.c:pv_irq_ops.irq_enable = 
__PV_IS_CALLEE_SAVE(xen_irq_enable_direct);

It just needs cleanups for the ENDPATCH and such.

Re: [PATCH 1/3] paravirt,xen: remove xen_patch()

2017-08-10 Thread Josh Poimboeuf 
On Thu, Aug 10, 2017 at 02:52:52PM +0200, Juergen Gross wrote:
> Xen's paravirt patch function xen_patch() does some special casing for
> irq_ops functions to apply relocations when those functions can be
> patched inline instead of calls.
> 
> Unfortunately none of the special case function replacements is small
> enough to be patches inline, so the special case never applies.
> 
> As xen_patch() will call paravirt_patch_default() in all cases it can
> be just dropped.
> 
> Signed-off-by: Juergen Gross 

Can the ENDPATCH and RELOC macros can also be removed, along with their
usages in xen-asm.S and xen-asm_64.S?

-- 
Josh

Re: [PATCH 1/3] paravirt,xen: remove xen_patch()

2017-08-10 Thread Josh Poimboeuf 
On Thu, Aug 10, 2017 at 02:52:52PM +0200, Juergen Gross wrote:
> Xen's paravirt patch function xen_patch() does some special casing for
> irq_ops functions to apply relocations when those functions can be
> patched inline instead of calls.
> 
> Unfortunately none of the special case function replacements is small
> enough to be patches inline, so the special case never applies.
> 
> As xen_patch() will call paravirt_patch_default() in all cases it can
> be just dropped.
> 
> Signed-off-by: Juergen Gross 

Can the ENDPATCH and RELOC macros can also be removed, along with their
usages in xen-asm.S and xen-asm_64.S?

-- 
Josh

Re: [PATCH 1/3] paravirt,xen: remove xen_patch()

2017-08-10 Thread Peter Zijlstra 
On Thu, Aug 10, 2017 at 02:52:52PM +0200, Juergen Gross wrote:
> Xen's paravirt patch function xen_patch() does some special casing for
> irq_ops functions to apply relocations when those functions can be
> patched inline instead of calls.
> 
> Unfortunately none of the special case function replacements is small
> enough to be patches inline, so the special case never applies.
> 
> As xen_patch() will call paravirt_patch_default() in all cases it can
> be just dropped.
> 
> Signed-off-by: Juergen Gross 
> ---
>  arch/x86/xen/enlighten_pv.c | 59 
> +
>  1 file changed, 1 insertion(+), 58 deletions(-)

> - SITE(pv_irq_ops, irq_enable);
> - SITE(pv_irq_ops, irq_disable);
> - SITE(pv_irq_ops, save_fl);
> - SITE(pv_irq_ops, restore_fl);

You forgot to remove the actual ASM that's then never used either.


 arch/x86/xen/Makefile  |   2 +-
 arch/x86/xen/xen-asm.S | 150 -
 arch/x86/xen/xen-ops.h |  12 
 3 files changed, 1 insertion(+), 163 deletions(-)

diff --git a/arch/x86/xen/Makefile b/arch/x86/xen/Makefile
index bced7a369a11..551e12ba2a7b 100644
--- a/arch/x86/xen/Makefile
+++ b/arch/x86/xen/Makefile
@@ -14,7 +14,7 @@ CFLAGS_enlighten_pv.o := $(nostackp)
 CFLAGS_mmu_pv.o:= $(nostackp)
 
 obj-y  := enlighten.o multicalls.o mmu.o irq.o \
-   time.o xen-asm.o xen-asm_$(BITS).o \
+   time.o xen-asm_$(BITS).o \
grant-table.o suspend.o platform-pci-unplug.o
 
 obj-$(CONFIG_XEN_PVHVM)+= enlighten_hvm.o mmu_hvm.o 
suspend_hvm.o
diff --git a/arch/x86/xen/xen-asm.S b/arch/x86/xen/xen-asm.S
deleted file mode 100644
index eff224df813f..
--- a/arch/x86/xen/xen-asm.S
+++ /dev/null
@@ -1,150 +0,0 @@
-/*
- * Asm versions of Xen pv-ops, suitable for either direct use or
- * inlining.  The inline versions are the same as the direct-use
- * versions, with the pre- and post-amble chopped off.
- *
- * This code is encoded for size rather than absolute efficiency, with
- * a view to being able to inline as much as possible.
- *
- * We only bother with direct forms (ie, vcpu in percpu data) of the
- * operations here; the indirect forms are better handled in C, since
- * they're generally too large to inline anyway.
- */
-
-#include 
-#include 
-#include 
-#include 
-
-#include "xen-asm.h"
-
-/*
- * Enable events.  This clears the event mask and tests the pending
- * event status with one and operation.  If there are pending events,
- * then enter the hypervisor to get them handled.
- */
-ENTRY(xen_irq_enable_direct)
-   FRAME_BEGIN
-   /* Unmask events */
-   movb $0, PER_CPU_VAR(xen_vcpu_info) + XEN_vcpu_info_mask
-
-   /*
-* Preempt here doesn't matter because that will deal with any
-* pending interrupts.  The pending check may end up being run
-* on the wrong CPU, but that doesn't hurt.
-*/
-
-   /* Test for pending */
-   testb $0xff, PER_CPU_VAR(xen_vcpu_info) + XEN_vcpu_info_pending
-   jz 1f
-
-2: call check_events
-1:
-ENDPATCH(xen_irq_enable_direct)
-   FRAME_END
-   ret
-   ENDPROC(xen_irq_enable_direct)
-   RELOC(xen_irq_enable_direct, 2b+1)
-
-
-/*
- * Disabling events is simply a matter of making the event mask
- * non-zero.
- */
-ENTRY(xen_irq_disable_direct)
-   movb $1, PER_CPU_VAR(xen_vcpu_info) + XEN_vcpu_info_mask
-ENDPATCH(xen_irq_disable_direct)
-   ret
-   ENDPROC(xen_irq_disable_direct)
-   RELOC(xen_irq_disable_direct, 0)
-
-/*
- * (xen_)save_fl is used to get the current interrupt enable status.
- * Callers expect the status to be in X86_EFLAGS_IF, and other bits
- * may be set in the return value.  We take advantage of this by
- * making sure that X86_EFLAGS_IF has the right value (and other bits
- * in that byte are 0), but other bits in the return value are
- * undefined.  We need to toggle the state of the bit, because Xen and
- * x86 use opposite senses (mask vs enable).
- */
-ENTRY(xen_save_fl_direct)
-   testb $0xff, PER_CPU_VAR(xen_vcpu_info) + XEN_vcpu_info_mask
-   setz %ah
-   addb %ah, %ah
-ENDPATCH(xen_save_fl_direct)
-   ret
-   ENDPROC(xen_save_fl_direct)
-   RELOC(xen_save_fl_direct, 0)
-
-
-/*
- * In principle the caller should be passing us a value return from
- * xen_save_fl_direct, but for robustness sake we test only the
- * X86_EFLAGS_IF flag rather than the whole byte. After setting the
- * interrupt mask state, it checks for unmasked pending events and
- * enters the hypervisor to get them delivered if so.
- */
-ENTRY(xen_restore_fl_direct)
-   FRAME_BEGIN
-#ifdef CONFIG_X86_64
-   testw $X86_EFLAGS_IF, %di
-#else
-   testb $X86_EFLAGS_IF>>8, %ah
-#endif
-   setz PER_CPU_VAR(xen_vcpu_info) + XEN_vcpu_info_mask
-   /*
-* Preempt here doesn't matter because

Re: [PATCH 1/3] paravirt,xen: remove xen_patch()

2017-08-10 Thread Peter Zijlstra 
On Thu, Aug 10, 2017 at 02:52:52PM +0200, Juergen Gross wrote:
> Xen's paravirt patch function xen_patch() does some special casing for
> irq_ops functions to apply relocations when those functions can be
> patched inline instead of calls.
> 
> Unfortunately none of the special case function replacements is small
> enough to be patches inline, so the special case never applies.
> 
> As xen_patch() will call paravirt_patch_default() in all cases it can
> be just dropped.
> 
> Signed-off-by: Juergen Gross 
> ---
>  arch/x86/xen/enlighten_pv.c | 59 
> +
>  1 file changed, 1 insertion(+), 58 deletions(-)

> - SITE(pv_irq_ops, irq_enable);
> - SITE(pv_irq_ops, irq_disable);
> - SITE(pv_irq_ops, save_fl);
> - SITE(pv_irq_ops, restore_fl);

You forgot to remove the actual ASM that's then never used either.


 arch/x86/xen/Makefile  |   2 +-
 arch/x86/xen/xen-asm.S | 150 -
 arch/x86/xen/xen-ops.h |  12 
 3 files changed, 1 insertion(+), 163 deletions(-)

diff --git a/arch/x86/xen/Makefile b/arch/x86/xen/Makefile
index bced7a369a11..551e12ba2a7b 100644
--- a/arch/x86/xen/Makefile
+++ b/arch/x86/xen/Makefile
@@ -14,7 +14,7 @@ CFLAGS_enlighten_pv.o := $(nostackp)
 CFLAGS_mmu_pv.o:= $(nostackp)
 
 obj-y  := enlighten.o multicalls.o mmu.o irq.o \
-   time.o xen-asm.o xen-asm_$(BITS).o \
+   time.o xen-asm_$(BITS).o \
grant-table.o suspend.o platform-pci-unplug.o
 
 obj-$(CONFIG_XEN_PVHVM)+= enlighten_hvm.o mmu_hvm.o 
suspend_hvm.o
diff --git a/arch/x86/xen/xen-asm.S b/arch/x86/xen/xen-asm.S
deleted file mode 100644
index eff224df813f..
--- a/arch/x86/xen/xen-asm.S
+++ /dev/null
@@ -1,150 +0,0 @@
-/*
- * Asm versions of Xen pv-ops, suitable for either direct use or
- * inlining.  The inline versions are the same as the direct-use
- * versions, with the pre- and post-amble chopped off.
- *
- * This code is encoded for size rather than absolute efficiency, with
- * a view to being able to inline as much as possible.
- *
- * We only bother with direct forms (ie, vcpu in percpu data) of the
- * operations here; the indirect forms are better handled in C, since
- * they're generally too large to inline anyway.
- */
-
-#include 
-#include 
-#include 
-#include 
-
-#include "xen-asm.h"
-
-/*
- * Enable events.  This clears the event mask and tests the pending
- * event status with one and operation.  If there are pending events,
- * then enter the hypervisor to get them handled.
- */
-ENTRY(xen_irq_enable_direct)
-   FRAME_BEGIN
-   /* Unmask events */
-   movb $0, PER_CPU_VAR(xen_vcpu_info) + XEN_vcpu_info_mask
-
-   /*
-* Preempt here doesn't matter because that will deal with any
-* pending interrupts.  The pending check may end up being run
-* on the wrong CPU, but that doesn't hurt.
-*/
-
-   /* Test for pending */
-   testb $0xff, PER_CPU_VAR(xen_vcpu_info) + XEN_vcpu_info_pending
-   jz 1f
-
-2: call check_events
-1:
-ENDPATCH(xen_irq_enable_direct)
-   FRAME_END
-   ret
-   ENDPROC(xen_irq_enable_direct)
-   RELOC(xen_irq_enable_direct, 2b+1)
-
-
-/*
- * Disabling events is simply a matter of making the event mask
- * non-zero.
- */
-ENTRY(xen_irq_disable_direct)
-   movb $1, PER_CPU_VAR(xen_vcpu_info) + XEN_vcpu_info_mask
-ENDPATCH(xen_irq_disable_direct)
-   ret
-   ENDPROC(xen_irq_disable_direct)
-   RELOC(xen_irq_disable_direct, 0)
-
-/*
- * (xen_)save_fl is used to get the current interrupt enable status.
- * Callers expect the status to be in X86_EFLAGS_IF, and other bits
- * may be set in the return value.  We take advantage of this by
- * making sure that X86_EFLAGS_IF has the right value (and other bits
- * in that byte are 0), but other bits in the return value are
- * undefined.  We need to toggle the state of the bit, because Xen and
- * x86 use opposite senses (mask vs enable).
- */
-ENTRY(xen_save_fl_direct)
-   testb $0xff, PER_CPU_VAR(xen_vcpu_info) + XEN_vcpu_info_mask
-   setz %ah
-   addb %ah, %ah
-ENDPATCH(xen_save_fl_direct)
-   ret
-   ENDPROC(xen_save_fl_direct)
-   RELOC(xen_save_fl_direct, 0)
-
-
-/*
- * In principle the caller should be passing us a value return from
- * xen_save_fl_direct, but for robustness sake we test only the
- * X86_EFLAGS_IF flag rather than the whole byte. After setting the
- * interrupt mask state, it checks for unmasked pending events and
- * enters the hypervisor to get them delivered if so.
- */
-ENTRY(xen_restore_fl_direct)
-   FRAME_BEGIN
-#ifdef CONFIG_X86_64
-   testw $X86_EFLAGS_IF, %di
-#else
-   testb $X86_EFLAGS_IF>>8, %ah
-#endif
-   setz PER_CPU_VAR(xen_vcpu_info) + XEN_vcpu_info_mask
-   /*
-* Preempt here doesn't matter because that will deal

[PATCH 1/3] paravirt,xen: remove xen_patch()

2017-08-10 Thread Juergen Gross 
Xen's paravirt patch function xen_patch() does some special casing for
irq_ops functions to apply relocations when those functions can be
patched inline instead of calls.

Unfortunately none of the special case function replacements is small
enough to be patches inline, so the special case never applies.

As xen_patch() will call paravirt_patch_default() in all cases it can
be just dropped.

Signed-off-by: Juergen Gross 
---
 arch/x86/xen/enlighten_pv.c | 59 +
 1 file changed, 1 insertion(+), 58 deletions(-)

diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c
index 811e4ddb3f37..98491521bb43 100644
--- a/arch/x86/xen/enlighten_pv.c
+++ b/arch/x86/xen/enlighten_pv.c
@@ -981,59 +981,6 @@ void __ref xen_setup_vcpu_info_placement(void)
}
 }
 
-static unsigned xen_patch(u8 type, u16 clobbers, void *insnbuf,
- unsigned long addr, unsigned len)
-{
-   char *start, *end, *reloc;
-   unsigned ret;
-
-   start = end = reloc = NULL;
-
-#define SITE(op, x)\
-   case PARAVIRT_PATCH(op.x):  \
-   if (xen_have_vcpu_info_placement) { \
-   start = (char *)xen_##x##_direct;   \
-   end = xen_##x##_direct_end; \
-   reloc = xen_##x##_direct_reloc; \
-   }   \
-   goto patch_site
-
-   switch (type) {
-   SITE(pv_irq_ops, irq_enable);
-   SITE(pv_irq_ops, irq_disable);
-   SITE(pv_irq_ops, save_fl);
-   SITE(pv_irq_ops, restore_fl);
-#undef SITE
-
-   patch_site:
-   if (start == NULL || (end-start) > len)
-   goto default_patch;
-
-   ret = paravirt_patch_insns(insnbuf, len, start, end);
-
-   /* Note: because reloc is assigned from something that
-  appears to be an array, gcc assumes it's non-null,
-  but doesn't know its relationship with start and
-  end. */
-   if (reloc > start && reloc < end) {
-   int reloc_off = reloc - start;
-   long *relocp = (long *)(insnbuf + reloc_off);
-   long delta = start - (char *)addr;
-
-   *relocp += delta;
-   }
-   break;
-
-   default_patch:
-   default:
-   ret = paravirt_patch_default(type, clobbers, insnbuf,
-addr, len);
-   break;
-   }
-
-   return ret;
-}
-
 static const struct pv_info xen_info __initconst = {
.shared_kernel_pmd = 0,
 
@@ -1043,10 +990,6 @@ static const struct pv_info xen_info __initconst = {
.name = "Xen",
 };
 
-static const struct pv_init_ops xen_init_ops __initconst = {
-   .patch = xen_patch,
-};
-
 static const struct pv_cpu_ops xen_cpu_ops __initconst = {
.cpuid = xen_cpuid,
 
@@ -1244,7 +1187,7 @@ asmlinkage __visible void __init xen_start_kernel(void)
 
/* Install Xen paravirt ops */
pv_info = xen_info;
-   pv_init_ops = xen_init_ops;
+   pv_init_ops.patch = paravirt_patch_default;
pv_cpu_ops = xen_cpu_ops;
 
x86_platform.get_nmi_reason = xen_get_nmi_reason;
-- 
2.12.3

[PATCH 1/3] paravirt,xen: remove xen_patch()

2017-08-10 Thread Juergen Gross 
Xen's paravirt patch function xen_patch() does some special casing for
irq_ops functions to apply relocations when those functions can be
patched inline instead of calls.

Unfortunately none of the special case function replacements is small
enough to be patches inline, so the special case never applies.

As xen_patch() will call paravirt_patch_default() in all cases it can
be just dropped.

Signed-off-by: Juergen Gross 
---
 arch/x86/xen/enlighten_pv.c | 59 +
 1 file changed, 1 insertion(+), 58 deletions(-)

diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c
index 811e4ddb3f37..98491521bb43 100644
--- a/arch/x86/xen/enlighten_pv.c
+++ b/arch/x86/xen/enlighten_pv.c
@@ -981,59 +981,6 @@ void __ref xen_setup_vcpu_info_placement(void)
}
 }
 
-static unsigned xen_patch(u8 type, u16 clobbers, void *insnbuf,
- unsigned long addr, unsigned len)
-{
-   char *start, *end, *reloc;
-   unsigned ret;
-
-   start = end = reloc = NULL;
-
-#define SITE(op, x)\
-   case PARAVIRT_PATCH(op.x):  \
-   if (xen_have_vcpu_info_placement) { \
-   start = (char *)xen_##x##_direct;   \
-   end = xen_##x##_direct_end; \
-   reloc = xen_##x##_direct_reloc; \
-   }   \
-   goto patch_site
-
-   switch (type) {
-   SITE(pv_irq_ops, irq_enable);
-   SITE(pv_irq_ops, irq_disable);
-   SITE(pv_irq_ops, save_fl);
-   SITE(pv_irq_ops, restore_fl);
-#undef SITE
-
-   patch_site:
-   if (start == NULL || (end-start) > len)
-   goto default_patch;
-
-   ret = paravirt_patch_insns(insnbuf, len, start, end);
-
-   /* Note: because reloc is assigned from something that
-  appears to be an array, gcc assumes it's non-null,
-  but doesn't know its relationship with start and
-  end. */
-   if (reloc > start && reloc < end) {
-   int reloc_off = reloc - start;
-   long *relocp = (long *)(insnbuf + reloc_off);
-   long delta = start - (char *)addr;
-
-   *relocp += delta;
-   }
-   break;
-
-   default_patch:
-   default:
-   ret = paravirt_patch_default(type, clobbers, insnbuf,
-addr, len);
-   break;
-   }
-
-   return ret;
-}
-
 static const struct pv_info xen_info __initconst = {
.shared_kernel_pmd = 0,
 
@@ -1043,10 +990,6 @@ static const struct pv_info xen_info __initconst = {
.name = "Xen",
 };
 
-static const struct pv_init_ops xen_init_ops __initconst = {
-   .patch = xen_patch,
-};
-
 static const struct pv_cpu_ops xen_cpu_ops __initconst = {
.cpuid = xen_cpuid,
 
@@ -1244,7 +1187,7 @@ asmlinkage __visible void __init xen_start_kernel(void)
 
/* Install Xen paravirt ops */
pv_info = xen_info;
-   pv_init_ops = xen_init_ops;
+   pv_init_ops.patch = paravirt_patch_default;
pv_cpu_ops = xen_cpu_ops;
 
x86_platform.get_nmi_reason = xen_get_nmi_reason;
-- 
2.12.3