[PATCH v3 12/15] x86/paravirt: move the Xen-only pv_cpu_ops under the PARAVIRT_XXL umbrella

From: Juergen Gross
Date: Tue Aug 28 2018 - 03:41:09 EST

Most of the paravirt ops defined in pv_cpu_ops are for Xen PV guests
only. Define them only if CONFIG_PARAVIRT_XXL is set.

Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
---
arch/x86/include/asm/debugreg.h | 2 +-
arch/x86/include/asm/desc.h | 4 ++--
arch/x86/include/asm/irqflags.h | 16 +++++++++++-----
arch/x86/include/asm/msr.h | 4 ++--
arch/x86/include/asm/paravirt.h | 19 +++++++++++++++++--
arch/x86/include/asm/paravirt_types.h | 5 ++++-
arch/x86/include/asm/pgtable.h | 6 ++++--
arch/x86/include/asm/processor.h | 4 ++--
arch/x86/include/asm/special_insns.h | 9 +++++++--
arch/x86/kernel/asm-offsets.c | 2 ++
arch/x86/kernel/asm-offsets_64.c | 2 ++
arch/x86/kernel/cpu/common.c | 2 +-
arch/x86/kernel/head_64.S | 2 ++
arch/x86/kernel/paravirt.c | 13 ++++++++++++-
arch/x86/kernel/paravirt_patch_32.c | 4 ++++
arch/x86/kernel/paravirt_patch_64.c | 6 +++++-
16 files changed, 78 insertions(+), 22 deletions(-)

diff --git a/arch/x86/include/asm/debugreg.h b/arch/x86/include/asm/debugreg.h
index 4505ac2735ad..9e5ca30738e5 100644
--- a/arch/x86/include/asm/debugreg.h
+++ b/arch/x86/include/asm/debugreg.h
@@ -8,7 +8,7 @@

DECLARE_PER_CPU(unsigned long, cpu_dr7);

-#ifndef CONFIG_PARAVIRT
+#ifndef CONFIG_PARAVIRT_XXL
/*
* These special macros can be used to get or set a debugging register
*/
diff --git a/arch/x86/include/asm/desc.h b/arch/x86/include/asm/desc.h
index 13c5ee878a47..68a99d2a5f33 100644
--- a/arch/x86/include/asm/desc.h
+++ b/arch/x86/include/asm/desc.h
@@ -108,7 +108,7 @@ static inline int desc_empty(const void *ptr)
return !(desc[0] | desc[1]);
}

-#ifdef CONFIG_PARAVIRT
+#ifdef CONFIG_PARAVIRT_XXL
#include <asm/paravirt.h>
#else
#define load_TR_desc() native_load_tr_desc()
@@ -134,7 +134,7 @@ static inline void paravirt_alloc_ldt(struct desc_struct *ldt, unsigned entries)
static inline void paravirt_free_ldt(struct desc_struct *ldt, unsigned entries)
{
}
-#endif /* CONFIG_PARAVIRT */
+#endif /* CONFIG_PARAVIRT_XXL */

#define store_ldt(ldt) asm("sldt %0" : "=m"(ldt))

diff --git a/arch/x86/include/asm/irqflags.h b/arch/x86/include/asm/irqflags.h
index 250bcd40d769..c5e74ba2c95e 100644
--- a/arch/x86/include/asm/irqflags.h
+++ b/arch/x86/include/asm/irqflags.h
@@ -121,6 +121,16 @@ static inline notrace unsigned long arch_local_irq_save(void)
#define ENABLE_INTERRUPTS(x) sti
#define DISABLE_INTERRUPTS(x) cli

+#ifdef CONFIG_X86_64
+#ifdef CONFIG_DEBUG_ENTRY
+#define SAVE_FLAGS(x) pushfq; popq %rax
+#endif
+#endif
+#endif /* __ASSEMBLY__ */
+#endif /* CONFIG_PARAVIRT */
+
+#ifndef CONFIG_PARAVIRT_XXL
+#ifdef __ASSEMBLY__
#ifdef CONFIG_X86_64
#define SWAPGS swapgs
/*
@@ -142,16 +152,12 @@ static inline notrace unsigned long arch_local_irq_save(void)
swapgs; \
sysretl

-#ifdef CONFIG_DEBUG_ENTRY
-#define SAVE_FLAGS(x) pushfq; popq %rax
-#endif
#else
#define INTERRUPT_RETURN iret
#endif

-
#endif /* __ASSEMBLY__ */
-#endif /* CONFIG_PARAVIRT */
+#endif /* CONFIG_PARAVIRT_XXL */

#ifndef __ASSEMBLY__
static inline int arch_irqs_disabled_flags(unsigned long flags)
diff --git a/arch/x86/include/asm/msr.h b/arch/x86/include/asm/msr.h
index 04addd6e0a4a..91e4cf189914 100644
--- a/arch/x86/include/asm/msr.h
+++ b/arch/x86/include/asm/msr.h
@@ -242,7 +242,7 @@ static inline unsigned long long native_read_pmc(int counter)
return EAX_EDX_VAL(val, low, high);
}

-#ifdef CONFIG_PARAVIRT
+#ifdef CONFIG_PARAVIRT_XXL
#include <asm/paravirt.h>
#else
#include <linux/errno.h>
@@ -305,7 +305,7 @@ do { \

#define rdpmcl(counter, val) ((val) = native_read_pmc(counter))

-#endif /* !CONFIG_PARAVIRT */
+#endif /* !CONFIG_PARAVIRT_XXL */

/*
* 64-bit version of wrmsr_safe():
diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h
index dbaedf1ed622..686a68004b5f 100644
--- a/arch/x86/include/asm/paravirt.h
+++ b/arch/x86/include/asm/paravirt.h
@@ -17,6 +17,7 @@
#include <linux/cpumask.h>
#include <asm/frame.h>

+#ifdef CONFIG_PARAVIRT_XXL
static inline void load_sp0(unsigned long sp0)
{
PVOP_VCALL1(cpu.load_sp0, sp0);
@@ -51,6 +52,7 @@ static inline void write_cr0(unsigned long x)
{
PVOP_VCALL1(cpu.write_cr0, x);
}
+#endif

static inline unsigned long read_cr2(void)
{
@@ -72,6 +74,7 @@ static inline void write_cr3(unsigned long x)
PVOP_VCALL1(mmu.write_cr3, x);
}

+#ifdef CONFIG_PARAVIRT_XXL
static inline void __write_cr4(unsigned long x)
{
PVOP_VCALL1(cpu.write_cr4, x);
@@ -88,6 +91,7 @@ static inline void write_cr8(unsigned long x)
PVOP_VCALL1(cpu.write_cr8, x);
}
#endif
+#endif

static inline void arch_safe_halt(void)
{
@@ -99,14 +103,13 @@ static inline void halt(void)
PVOP_VCALL0(irq.halt);
}

+#ifdef CONFIG_PARAVIRT_XXL
static inline void wbinvd(void)
{
PVOP_VCALL0(cpu.wbinvd);
}

-#ifdef CONFIG_PARAVIRT_XXL
#define get_kernel_rpl() (pv_info.kernel_rpl)
-#endif

static inline u64 paravirt_read_msr(unsigned msr)
{
@@ -171,6 +174,7 @@ static inline int rdmsrl_safe(unsigned msr, unsigned long long *p)
*p = paravirt_read_msr_safe(msr, &err);
return err;
}
+#endif

static inline unsigned long long paravirt_sched_clock(void)
{
@@ -186,6 +190,7 @@ static inline u64 paravirt_steal_clock(int cpu)
return PVOP_CALL1(u64, time.steal_clock, cpu);
}

+#ifdef CONFIG_PARAVIRT_XXL
static inline unsigned long long paravirt_read_pmc(int counter)
{
return PVOP_CALL1(u64, cpu.read_pmc, counter);
@@ -230,6 +235,7 @@ static inline unsigned long paravirt_store_tr(void)
{
return PVOP_CALL0(unsigned long, cpu.store_tr);
}
+
#define store_tr(tr) ((tr) = paravirt_store_tr())
static inline void load_TLS(struct thread_struct *t, unsigned cpu)
{
@@ -263,6 +269,7 @@ static inline void set_iopl_mask(unsigned mask)
{
PVOP_VCALL1(cpu.set_iopl_mask, mask);
}
+#endif

/* The paravirtualized I/O functions */
static inline void slow_down_io(void)
@@ -618,6 +625,7 @@ static inline void pmd_clear(pmd_t *pmdp)
}
#endif /* CONFIG_X86_PAE */

+#ifdef CONFIG_PARAVIRT_XXL
#define __HAVE_ARCH_START_CONTEXT_SWITCH
static inline void arch_start_context_switch(struct task_struct *prev)
{
@@ -628,6 +636,7 @@ static inline void arch_end_context_switch(struct task_struct *next)
{
PVOP_VCALL1(cpu.end_context_switch, next);
}
+#endif

#define __HAVE_ARCH_ENTER_LAZY_MMU_MODE
static inline void arch_enter_lazy_mmu_mode(void)
@@ -870,10 +879,12 @@ extern void default_banner(void);
#define PARA_INDIRECT(addr) *%cs:addr
#endif

+#ifdef CONFIG_PARAVIRT_XXL
#define INTERRUPT_RETURN \
PARA_SITE(PARA_PATCH(PV_CPU_iret), \
ANNOTATE_RETPOLINE_SAFE; \
jmp PARA_INDIRECT(pv_ops+PV_CPU_iret);)
+#endif

#define DISABLE_INTERRUPTS(clobbers) \
PARA_SITE(PARA_PATCH(PV_IRQ_irq_disable), \
@@ -890,6 +901,7 @@ extern void default_banner(void);
PV_RESTORE_REGS(clobbers | CLBR_CALLEE_SAVE);)

#ifdef CONFIG_X86_64
+#ifdef CONFIG_PARAVIRT_XXL
/*
* If swapgs is used while the userspace stack is still current,
* there's no way to call a pvop. The PV replacement *must* be
@@ -909,15 +921,18 @@ extern void default_banner(void);
ANNOTATE_RETPOLINE_SAFE; \
call PARA_INDIRECT(pv_ops+PV_CPU_swapgs); \
)
+#endif

#define GET_CR2_INTO_RAX \
ANNOTATE_RETPOLINE_SAFE; \
call PARA_INDIRECT(pv_ops+PV_MMU_read_cr2);

+#ifdef CONFIG_PARAVIRT_XXL
#define USERGS_SYSRET64 \
PARA_SITE(PARA_PATCH(PV_CPU_usergs_sysret64), \
ANNOTATE_RETPOLINE_SAFE; \
jmp PARA_INDIRECT(pv_ops+PV_CPU_usergs_sysret64);)
+#endif

#ifdef CONFIG_DEBUG_ENTRY
#define SAVE_FLAGS(clobbers) \
diff --git a/arch/x86/include/asm/paravirt_types.h b/arch/x86/include/asm/paravirt_types.h
index 98e1110354b8..30ee6538442c 100644
--- a/arch/x86/include/asm/paravirt_types.h
+++ b/arch/x86/include/asm/paravirt_types.h
@@ -106,6 +106,9 @@ struct pv_time_ops {

struct pv_cpu_ops {
/* hooks for various privileged instructions */
+ void (*io_delay)(void);
+
+#ifdef CONFIG_PARAVIRT_XXL
unsigned long (*get_debugreg)(int regno);
void (*set_debugreg)(int regno, unsigned long value);

@@ -143,7 +146,6 @@ struct pv_cpu_ops {
void (*set_iopl_mask)(unsigned mask);

void (*wbinvd)(void);
- void (*io_delay)(void);

/* cpuid emulation, mostly so that caps bits can be disabled */
void (*cpuid)(unsigned int *eax, unsigned int *ebx,
@@ -178,6 +180,7 @@ struct pv_cpu_ops {

void (*start_context_switch)(struct task_struct *prev);
void (*end_context_switch)(struct task_struct *next);
+#endif
} __no_randomize_layout;

struct pv_irq_ops {
diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
index e4ffa565a69f..5bb0fe3b7e00 100644
--- a/arch/x86/include/asm/pgtable.h
+++ b/arch/x86/include/asm/pgtable.h
@@ -111,10 +111,12 @@ extern pmdval_t early_pmd_flags;
#define pte_val(x) native_pte_val(x)
#define __pte(x) native_make_pte(x)

-#define arch_end_context_switch(prev) do {} while(0)
-
#endif /* CONFIG_PARAVIRT */

+#ifndef CONFIG_PARAVIRT_XXL
+#define arch_end_context_switch(prev) do {} while(0)
+#endif /* CONFIG_PARAVIRT_XXL */
+
/*
* The following only work if pte_present() is true.
* Undefined behaviour if not..
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index c24297268ebc..a6220620dcf8 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -576,7 +576,7 @@ static inline bool on_thread_stack(void)
current_stack_pointer) < THREAD_SIZE;
}

-#ifdef CONFIG_PARAVIRT
+#ifdef CONFIG_PARAVIRT_XXL
#include <asm/paravirt.h>
#else
#define __cpuid native_cpuid
@@ -587,7 +587,7 @@ static inline void load_sp0(unsigned long sp0)
}

#define set_iopl_mask native_set_iopl_mask
-#endif /* CONFIG_PARAVIRT */
+#endif /* CONFIG_PARAVIRT_XXL */

/* Free all resources held by a thread. */
extern void release_thread(struct task_struct *);
diff --git a/arch/x86/include/asm/special_insns.h b/arch/x86/include/asm/special_insns.h
index 317fc59b512c..2aa6ce4bf159 100644
--- a/arch/x86/include/asm/special_insns.h
+++ b/arch/x86/include/asm/special_insns.h
@@ -143,8 +143,9 @@ static inline unsigned long __read_cr4(void)

#ifdef CONFIG_PARAVIRT
#include <asm/paravirt.h>
-#else
+#endif

+#ifndef CONFIG_PARAVIRT_XXL
static inline unsigned long read_cr0(void)
{
return native_read_cr0();
@@ -154,7 +155,9 @@ static inline void write_cr0(unsigned long x)
{
native_write_cr0(x);
}
+#endif

+#ifndef CONFIG_PARAVIRT
static inline unsigned long read_cr2(void)
{
return native_read_cr2();
@@ -178,7 +181,9 @@ static inline void write_cr3(unsigned long x)
{
native_write_cr3(x);
}
+#endif

+#ifndef CONFIG_PARAVIRT_XXL
static inline void __write_cr4(unsigned long x)
{
native_write_cr4(x);
@@ -208,7 +213,7 @@ static inline void load_gs_index(unsigned selector)

#endif

-#endif/* CONFIG_PARAVIRT */
+#endif/* CONFIG_PARAVIRT_XXL */

static inline void clflush(volatile void *__p)
{
diff --git a/arch/x86/kernel/asm-offsets.c b/arch/x86/kernel/asm-offsets.c
index 37e323f3d8c9..0fe233d98d17 100644
--- a/arch/x86/kernel/asm-offsets.c
+++ b/arch/x86/kernel/asm-offsets.c
@@ -68,7 +68,9 @@ void common(void) {
BLANK();
OFFSET(PV_IRQ_irq_disable, paravirt_patch_template, irq.irq_disable);
OFFSET(PV_IRQ_irq_enable, paravirt_patch_template, irq.irq_enable);
+#ifdef CONFIG_PARAVIRT_XXL
OFFSET(PV_CPU_iret, paravirt_patch_template, cpu.iret);
+#endif
OFFSET(PV_MMU_read_cr2, paravirt_patch_template, mmu.read_cr2);
#endif

diff --git a/arch/x86/kernel/asm-offsets_64.c b/arch/x86/kernel/asm-offsets_64.c
index 3384b03e717f..2a15d420a84d 100644
--- a/arch/x86/kernel/asm-offsets_64.c
+++ b/arch/x86/kernel/asm-offsets_64.c
@@ -21,9 +21,11 @@ static char syscalls_ia32[] = {
int main(void)
{
#ifdef CONFIG_PARAVIRT
+#ifdef CONFIG_PARAVIRT_XXL
OFFSET(PV_CPU_usergs_sysret64, paravirt_patch_template,
cpu.usergs_sysret64);
OFFSET(PV_CPU_swapgs, paravirt_patch_template, cpu.swapgs);
+#endif
#ifdef CONFIG_DEBUG_ENTRY
OFFSET(PV_IRQ_save_fl, paravirt_patch_template, irq.save_fl);
#endif
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 1f089e1c79d3..ffe6904eca1c 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -1239,7 +1239,7 @@ static void generic_identify(struct cpuinfo_x86 *c)
* ESPFIX issue, we can change this.
*/
#ifdef CONFIG_X86_32
-# ifdef CONFIG_PARAVIRT
+# ifdef CONFIG_PARAVIRT_XXL
do {
extern void native_iret(void);
if (pv_ops.cpu.iret == native_iret)
diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S
index 15ebc2fc166e..a5bd72a0ee1a 100644
--- a/arch/x86/kernel/head_64.S
+++ b/arch/x86/kernel/head_64.S
@@ -31,6 +31,8 @@
#define GET_CR2_INTO(reg) GET_CR2_INTO_RAX ; movq %rax, reg
#else
#define GET_CR2_INTO(reg) movq %cr2, reg
+#endif
+#ifndef CONFIG_PARAVIRT_XXL
#define INTERRUPT_RETURN iretq
#endif

diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c
index ee7da9ec3ea2..d29b46621543 100644
--- a/arch/x86/kernel/paravirt.c
+++ b/arch/x86/kernel/paravirt.c
@@ -101,6 +101,7 @@ static unsigned paravirt_patch_call(void *insnbuf, const void *target,
return 5;
}

+#ifdef CONFIG_PARAVIRT_XXL
static unsigned paravirt_patch_jmp(void *insnbuf, const void *target,
unsigned long addr, unsigned len)
{
@@ -119,6 +120,7 @@ static unsigned paravirt_patch_jmp(void *insnbuf, const void *target,

return 5;
}
+#endif

DEFINE_STATIC_KEY_TRUE(virt_spin_lock_key);

@@ -150,10 +152,12 @@ unsigned paravirt_patch_default(u8 type, void *insnbuf,
else if (opfunc == _paravirt_ident_64)
ret = paravirt_patch_ident_64(insnbuf, len);

+#ifdef CONFIG_PARAVIRT_XXL
else if (type == PARAVIRT_PATCH(cpu.iret) ||
type == PARAVIRT_PATCH(cpu.usergs_sysret64))
/* If operation requires a jmp, then jmp */
ret = paravirt_patch_jmp(insnbuf, opfunc, addr, len);
+#endif
else
/* Otherwise call the function. */
ret = paravirt_patch_call(insnbuf, opfunc, addr, len);
@@ -262,6 +266,7 @@ void paravirt_flush_lazy_mmu(void)
preempt_enable();
}

+#ifdef CONFIG_PARAVIRT_XXL
void paravirt_start_context_switch(struct task_struct *prev)
{
BUG_ON(preemptible());
@@ -282,6 +287,7 @@ void paravirt_end_context_switch(struct task_struct *next)
if (test_and_clear_ti_thread_flag(task_thread_info(next), TIF_LAZY_MMU_UPDATES))
arch_enter_lazy_mmu_mode();
}
+#endif

enum paravirt_lazy_mode paravirt_get_lazy_mode(void)
{
@@ -320,6 +326,9 @@ struct paravirt_patch_template pv_ops = {
.time.steal_clock = native_steal_clock,

/* Cpu ops. */
+ .cpu.io_delay = native_io_delay,
+
+#ifdef CONFIG_PARAVIRT_XXL
.cpu.cpuid = native_cpuid,
.cpu.get_debugreg = native_get_debugreg,
.cpu.set_debugreg = native_set_debugreg,
@@ -361,10 +370,10 @@ struct paravirt_patch_template pv_ops = {
.cpu.swapgs = native_swapgs,

.cpu.set_iopl_mask = native_set_iopl_mask,
- .cpu.io_delay = native_io_delay,

.cpu.start_context_switch = paravirt_nop,
.cpu.end_context_switch = paravirt_nop,
+#endif

/* Irq ops. */
.irq.save_fl = __PV_IS_CALLEE_SAVE(native_save_fl),
@@ -463,10 +472,12 @@ struct paravirt_patch_template pv_ops = {
#endif
};

+#ifdef CONFIG_PARAVIRT_XXL
/* At this point, native_get/set_debugreg has real function entries */
NOKPROBE_SYMBOL(native_get_debugreg);
NOKPROBE_SYMBOL(native_set_debugreg);
NOKPROBE_SYMBOL(native_load_idt);
+#endif

EXPORT_SYMBOL_GPL(pv_ops);
EXPORT_SYMBOL_GPL(pv_info);
diff --git a/arch/x86/kernel/paravirt_patch_32.c b/arch/x86/kernel/paravirt_patch_32.c
index 026fa43e9261..5a20aa56efc0 100644
--- a/arch/x86/kernel/paravirt_patch_32.c
+++ b/arch/x86/kernel/paravirt_patch_32.c
@@ -5,7 +5,9 @@ DEF_NATIVE(irq, irq_disable, "cli");
DEF_NATIVE(irq, irq_enable, "sti");
DEF_NATIVE(irq, restore_fl, "push %eax; popf");
DEF_NATIVE(irq, save_fl, "pushf; pop %eax");
+#ifdef CONFIG_PARAVIRT_XXL
DEF_NATIVE(cpu, iret, "iret");
+#endif
DEF_NATIVE(mmu, read_cr2, "mov %cr2, %eax");
DEF_NATIVE(mmu, write_cr3, "mov %eax, %cr3");
DEF_NATIVE(mmu, read_cr3, "mov %cr3, %eax");
@@ -45,7 +47,9 @@ unsigned native_patch(u8 type, void *ibuf, unsigned long addr, unsigned len)
PATCH_SITE(irq, irq_enable);
PATCH_SITE(irq, restore_fl);
PATCH_SITE(irq, save_fl);
+#ifdef CONFIG_PARAVIRT_XXL
PATCH_SITE(cpu, iret);
+#endif
PATCH_SITE(mmu, read_cr2);
PATCH_SITE(mmu, read_cr3);
PATCH_SITE(mmu, write_cr3);
diff --git a/arch/x86/kernel/paravirt_patch_64.c b/arch/x86/kernel/paravirt_patch_64.c
index 582e893728e8..461aba038ada 100644
--- a/arch/x86/kernel/paravirt_patch_64.c
+++ b/arch/x86/kernel/paravirt_patch_64.c
@@ -10,10 +10,12 @@ DEF_NATIVE(irq, save_fl, "pushfq; popq %rax");
DEF_NATIVE(mmu, read_cr2, "movq %cr2, %rax");
DEF_NATIVE(mmu, read_cr3, "movq %cr3, %rax");
DEF_NATIVE(mmu, write_cr3, "movq %rdi, %cr3");
+#ifdef CONFIG_PARAVIRT_XXL
DEF_NATIVE(cpu, wbinvd, "wbinvd");

DEF_NATIVE(cpu, usergs_sysret64, "swapgs; sysretq");
DEF_NATIVE(cpu, swapgs, "swapgs");
+#endif

DEF_NATIVE(, mov32, "mov %edi, %eax");
DEF_NATIVE(, mov64, "mov %rdi, %rax");
@@ -53,12 +55,14 @@ unsigned native_patch(u8 type, void *ibuf, unsigned long addr, unsigned len)
PATCH_SITE(irq, save_fl);
PATCH_SITE(irq, irq_enable);
PATCH_SITE(irq, irq_disable);
+#ifdef CONFIG_PARAVIRT_XXL
PATCH_SITE(cpu, usergs_sysret64);
PATCH_SITE(cpu, swapgs);
+ PATCH_SITE(cpu, wbinvd);
+#endif
PATCH_SITE(mmu, read_cr2);
PATCH_SITE(mmu, read_cr3);
PATCH_SITE(mmu, write_cr3);
- PATCH_SITE(cpu, wbinvd);
#if defined(CONFIG_PARAVIRT_SPINLOCKS)
case PARAVIRT_PATCH(lock.queued_spin_unlock):
if (pv_is_native_spin_unlock()) {
--
2.16.4