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Subject[PATCH 1/2] x86/xen: remove 32-bit Xen PV guest support
Date
Xen is requiring 64-bit machines today. There is no need to carry the
burden of 32-bit PV guest support in the kernel any longer, as new
guests can be either HVM or PVH, or they can use a 64 bit kernel.

Remove the 32-bit Xen PV support from the kernel.

Signed-off-by: Juergen Gross <jgross@suse.com>
---
arch/x86/entry/entry_32.S | 93 ------------
arch/x86/include/asm/proto.h | 2 +-
arch/x86/include/asm/segment.h | 2 +-
arch/x86/include/asm/traps.h | 2 +-
arch/x86/xen/Kconfig | 3 +-
arch/x86/xen/Makefile | 4 +-
arch/x86/xen/apic.c | 17 ---
arch/x86/xen/enlighten_pv.c | 45 +-----
arch/x86/xen/mmu_pv.c | 326 ++++-------------------------------------
arch/x86/xen/p2m.c | 4 -
arch/x86/xen/setup.c | 44 +-----
arch/x86/xen/smp_pv.c | 19 +--
arch/x86/xen/xen-asm.S | 14 --
arch/x86/xen/xen-asm_32.S | 207 --------------------------
arch/x86/xen/xen-head.S | 6 -
arch/x86/xen/xen-ops.h | 5 -
drivers/xen/Kconfig | 4 +-
17 files changed, 42 insertions(+), 755 deletions(-)
delete mode 100644 arch/x86/xen/xen-asm_32.S

diff --git a/arch/x86/entry/entry_32.S b/arch/x86/entry/entry_32.S
index 7b23431be5cb..d4464af28212 100644
--- a/arch/x86/entry/entry_32.S
+++ b/arch/x86/entry/entry_32.S
@@ -787,16 +787,6 @@ GLOBAL(__begin_SYSENTER_singlestep_region)
* will ignore all of the single-step traps generated in this range.
*/

-#ifdef CONFIG_XEN_PV
-/*
- * Xen doesn't set %esp to be precisely what the normal SYSENTER
- * entry point expects, so fix it up before using the normal path.
- */
-ENTRY(xen_sysenter_target)
- addl $5*4, %esp /* remove xen-provided frame */
- jmp .Lsysenter_past_esp
-#endif
-
/*
* 32-bit SYSENTER entry.
*
@@ -1249,89 +1239,6 @@ ENTRY(spurious_interrupt_bug)
jmp common_exception
END(spurious_interrupt_bug)

-#ifdef CONFIG_XEN_PV
-ENTRY(xen_hypervisor_callback)
- pushl $-1 /* orig_ax = -1 => not a system call */
- SAVE_ALL
- ENCODE_FRAME_POINTER
- TRACE_IRQS_OFF
-
- /*
- * Check to see if we got the event in the critical
- * region in xen_iret_direct, after we've reenabled
- * events and checked for pending events. This simulates
- * iret instruction's behaviour where it delivers a
- * pending interrupt when enabling interrupts:
- */
- movl PT_EIP(%esp), %eax
- cmpl $xen_iret_start_crit, %eax
- jb 1f
- cmpl $xen_iret_end_crit, %eax
- jae 1f
-
- jmp xen_iret_crit_fixup
-
-ENTRY(xen_do_upcall)
-1: mov %esp, %eax
- call xen_evtchn_do_upcall
-#ifndef CONFIG_PREEMPT
- call xen_maybe_preempt_hcall
-#endif
- jmp ret_from_intr
-ENDPROC(xen_hypervisor_callback)
-
-/*
- * Hypervisor uses this for application faults while it executes.
- * We get here for two reasons:
- * 1. Fault while reloading DS, ES, FS or GS
- * 2. Fault while executing IRET
- * Category 1 we fix up by reattempting the load, and zeroing the segment
- * register if the load fails.
- * Category 2 we fix up by jumping to do_iret_error. We cannot use the
- * normal Linux return path in this case because if we use the IRET hypercall
- * to pop the stack frame we end up in an infinite loop of failsafe callbacks.
- * We distinguish between categories by maintaining a status value in EAX.
- */
-ENTRY(xen_failsafe_callback)
- pushl %eax
- movl $1, %eax
-1: mov 4(%esp), %ds
-2: mov 8(%esp), %es
-3: mov 12(%esp), %fs
-4: mov 16(%esp), %gs
- /* EAX == 0 => Category 1 (Bad segment)
- EAX != 0 => Category 2 (Bad IRET) */
- testl %eax, %eax
- popl %eax
- lea 16(%esp), %esp
- jz 5f
- jmp iret_exc
-5: pushl $-1 /* orig_ax = -1 => not a system call */
- SAVE_ALL
- ENCODE_FRAME_POINTER
- jmp ret_from_exception
-
-.section .fixup, "ax"
-6: xorl %eax, %eax
- movl %eax, 4(%esp)
- jmp 1b
-7: xorl %eax, %eax
- movl %eax, 8(%esp)
- jmp 2b
-8: xorl %eax, %eax
- movl %eax, 12(%esp)
- jmp 3b
-9: xorl %eax, %eax
- movl %eax, 16(%esp)
- jmp 4b
-.previous
- _ASM_EXTABLE(1b, 6b)
- _ASM_EXTABLE(2b, 7b)
- _ASM_EXTABLE(3b, 8b)
- _ASM_EXTABLE(4b, 9b)
-ENDPROC(xen_failsafe_callback)
-#endif /* CONFIG_XEN_PV */
-
#ifdef CONFIG_XEN_PVHVM
BUILD_INTERRUPT3(xen_hvm_callback_vector, HYPERVISOR_CALLBACK_VECTOR,
xen_evtchn_do_upcall)
diff --git a/arch/x86/include/asm/proto.h b/arch/x86/include/asm/proto.h
index 6e81788a30c1..e5a13a138b01 100644
--- a/arch/x86/include/asm/proto.h
+++ b/arch/x86/include/asm/proto.h
@@ -25,7 +25,7 @@ void entry_SYSENTER_compat(void);
void __end_entry_SYSENTER_compat(void);
void entry_SYSCALL_compat(void);
void entry_INT80_compat(void);
-#if defined(CONFIG_X86_64) && defined(CONFIG_XEN_PV)
+#if defined(CONFIG_XEN_PV)
void xen_entry_INT80_compat(void);
#endif
#endif
diff --git a/arch/x86/include/asm/segment.h b/arch/x86/include/asm/segment.h
index ac3892920419..7f485fadfe6e 100644
--- a/arch/x86/include/asm/segment.h
+++ b/arch/x86/include/asm/segment.h
@@ -289,7 +289,7 @@ static inline void vdso_read_cpunode(unsigned *cpu, unsigned *node)
extern const char early_idt_handler_array[NUM_EXCEPTION_VECTORS][EARLY_IDT_HANDLER_SIZE];
extern void early_ignore_irq(void);

-#if defined(CONFIG_X86_64) && defined(CONFIG_XEN_PV)
+#if defined(CONFIG_XEN_PV)
extern const char xen_early_idt_handler_array[NUM_EXCEPTION_VECTORS][XEN_EARLY_IDT_HANDLER_SIZE];
#endif

diff --git a/arch/x86/include/asm/traps.h b/arch/x86/include/asm/traps.h
index 7d6f3f3fad78..2b142e58657e 100644
--- a/arch/x86/include/asm/traps.h
+++ b/arch/x86/include/asm/traps.h
@@ -36,7 +36,7 @@ asmlinkage void machine_check(void);
#endif /* CONFIG_X86_MCE */
asmlinkage void simd_coprocessor_error(void);

-#if defined(CONFIG_X86_64) && defined(CONFIG_XEN_PV)
+#if defined(CONFIG_XEN_PV)
asmlinkage void xen_divide_error(void);
asmlinkage void xen_xennmi(void);
asmlinkage void xen_xendebug(void);
diff --git a/arch/x86/xen/Kconfig b/arch/x86/xen/Kconfig
index e07abefd3d26..dbd7cd38b914 100644
--- a/arch/x86/xen/Kconfig
+++ b/arch/x86/xen/Kconfig
@@ -18,6 +18,7 @@ config XEN_PV
bool "Xen PV guest support"
default y
depends on XEN
+ depends on X86_64
select PARAVIRT_XXL
select XEN_HAVE_PVMMU
select XEN_HAVE_VPMU
@@ -49,7 +50,7 @@ config XEN_PVHVM_SMP

config XEN_512GB
bool "Limit Xen pv-domain memory to 512GB"
- depends on XEN_PV && X86_64
+ depends on XEN_PV
default y
help
Limit paravirtualized user domains to 512GB of RAM.
diff --git a/arch/x86/xen/Makefile b/arch/x86/xen/Makefile
index 084de77a109e..d42737f31304 100644
--- a/arch/x86/xen/Makefile
+++ b/arch/x86/xen/Makefile
@@ -1,5 +1,5 @@
# SPDX-License-Identifier: GPL-2.0
-OBJECT_FILES_NON_STANDARD_xen-asm_$(BITS).o := y
+OBJECT_FILES_NON_STANDARD_xen-asm_64.o := y

ifdef CONFIG_FUNCTION_TRACER
# Do not profile debug and lowlevel utilities
@@ -34,7 +34,7 @@ obj-$(CONFIG_XEN_PV) += mmu_pv.o
obj-$(CONFIG_XEN_PV) += irq.o
obj-$(CONFIG_XEN_PV) += multicalls.o
obj-$(CONFIG_XEN_PV) += xen-asm.o
-obj-$(CONFIG_XEN_PV) += xen-asm_$(BITS).o
+obj-$(CONFIG_XEN_PV) += xen-asm_64.o

obj-$(CONFIG_XEN_PVH) += enlighten_pvh.o

diff --git a/arch/x86/xen/apic.c b/arch/x86/xen/apic.c
index 5e53bfbe5823..ea6e9c54da9d 100644
--- a/arch/x86/xen/apic.c
+++ b/arch/x86/xen/apic.c
@@ -58,10 +58,6 @@ static u32 xen_apic_read(u32 reg)

if (reg == APIC_LVR)
return 0x14;
-#ifdef CONFIG_X86_32
- if (reg == APIC_LDR)
- return SET_APIC_LOGICAL_ID(1UL << smp_processor_id());
-#endif
if (reg != APIC_ID)
return 0;

@@ -127,14 +123,6 @@ static int xen_phys_pkg_id(int initial_apic_id, int index_msb)
return initial_apic_id >> index_msb;
}

-#ifdef CONFIG_X86_32
-static int xen_x86_32_early_logical_apicid(int cpu)
-{
- /* Match with APIC_LDR read. Otherwise setup_local_APIC complains. */
- return 1 << cpu;
-}
-#endif
-
static void xen_noop(void)
{
}
@@ -197,11 +185,6 @@ static struct apic xen_pv_apic = {
.icr_write = xen_apic_icr_write,
.wait_icr_idle = xen_noop,
.safe_wait_icr_idle = xen_safe_apic_wait_icr_idle,
-
-#ifdef CONFIG_X86_32
- /* generic_processor_info and setup_local_APIC. */
- .x86_32_early_logical_apicid = xen_x86_32_early_logical_apicid,
-#endif
};

static void __init xen_apic_check(void)
diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c
index 4722ba2966ac..cc14bf6354b6 100644
--- a/arch/x86/xen/enlighten_pv.c
+++ b/arch/x86/xen/enlighten_pv.c
@@ -545,13 +545,8 @@ static void xen_load_tls(struct thread_struct *t, unsigned int cpu)
* exception between the new %fs descriptor being loaded and
* %fs being effectively cleared at __switch_to().
*/
- if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_CPU) {
-#ifdef CONFIG_X86_32
- lazy_load_gs(0);
-#else
+ if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_CPU)
loadsegment(fs, 0);
-#endif
- }

xen_mc_batch();

@@ -562,13 +557,11 @@ static void xen_load_tls(struct thread_struct *t, unsigned int cpu)
xen_mc_issue(PARAVIRT_LAZY_CPU);
}

-#ifdef CONFIG_X86_64
static void xen_load_gs_index(unsigned int idx)
{
if (HYPERVISOR_set_segment_base(SEGBASE_GS_USER_SEL, idx))
BUG();
}
-#endif

static void xen_write_ldt_entry(struct desc_struct *dt, int entrynum,
const void *ptr)
@@ -587,7 +580,6 @@ static void xen_write_ldt_entry(struct desc_struct *dt, int entrynum,
preempt_enable();
}

-#ifdef CONFIG_X86_64
struct trap_array_entry {
void (*orig)(void);
void (*xen)(void);
@@ -657,7 +649,6 @@ static bool __ref get_trap_addr(void **addr, unsigned int ist)

return true;
}
-#endif

static int cvt_gate_to_trap(int vector, const gate_desc *val,
struct trap_info *info)
@@ -670,10 +661,8 @@ static int cvt_gate_to_trap(int vector, const gate_desc *val,
info->vector = vector;

addr = gate_offset(val);
-#ifdef CONFIG_X86_64
if (!get_trap_addr((void **)&addr, val->bits.ist))
return 0;
-#endif /* CONFIG_X86_64 */
info->address = addr;

info->cs = gate_segment(val);
@@ -877,7 +866,7 @@ static void xen_write_cr4(unsigned long cr4)

native_write_cr4(cr4);
}
-#ifdef CONFIG_X86_64
+
static inline unsigned long xen_read_cr8(void)
{
return 0;
@@ -886,7 +875,6 @@ static inline void xen_write_cr8(unsigned long val)
{
BUG_ON(val);
}
-#endif

static u64 xen_read_msr_safe(unsigned int msr, int *err)
{
@@ -911,7 +899,6 @@ static int xen_write_msr_safe(unsigned int msr, unsigned low, unsigned high)
ret = 0;

switch (msr) {
-#ifdef CONFIG_X86_64
unsigned which;
u64 base;

@@ -924,7 +911,6 @@ static int xen_write_msr_safe(unsigned int msr, unsigned low, unsigned high)
if (HYPERVISOR_set_segment_base(which, base) != 0)
ret = -EIO;
break;
-#endif

case MSR_STAR:
case MSR_CSTAR:
@@ -1005,9 +991,7 @@ void __init xen_setup_vcpu_info_placement(void)
static const struct pv_info xen_info __initconst = {
.shared_kernel_pmd = 0,

-#ifdef CONFIG_X86_64
.extra_user_64bit_cs = FLAT_USER_CS64,
-#endif
.name = "Xen",
};

@@ -1022,10 +1006,8 @@ static const struct pv_cpu_ops xen_cpu_ops __initconst = {

.write_cr4 = xen_write_cr4,

-#ifdef CONFIG_X86_64
.read_cr8 = xen_read_cr8,
.write_cr8 = xen_write_cr8,
-#endif

.wbinvd = native_wbinvd,

@@ -1038,18 +1020,14 @@ static const struct pv_cpu_ops xen_cpu_ops __initconst = {
.read_pmc = xen_read_pmc,

.iret = xen_iret,
-#ifdef CONFIG_X86_64
.usergs_sysret64 = xen_sysret64,
-#endif

.load_tr_desc = paravirt_nop,
.set_ldt = xen_set_ldt,
.load_gdt = xen_load_gdt,
.load_idt = xen_load_idt,
.load_tls = xen_load_tls,
-#ifdef CONFIG_X86_64
.load_gs_index = xen_load_gs_index,
-#endif

.alloc_ldt = xen_alloc_ldt,
.free_ldt = xen_free_ldt,
@@ -1312,15 +1290,7 @@ asmlinkage __visible void __init xen_start_kernel(void)

/* keep using Xen gdt for now; no urgent need to change it */

-#ifdef CONFIG_X86_32
- pv_info.kernel_rpl = 1;
- if (xen_feature(XENFEAT_supervisor_mode_kernel))
- pv_info.kernel_rpl = 0;
-#else
pv_info.kernel_rpl = 0;
-#endif
- /* set the limit of our address space */
- xen_reserve_top();

/*
* We used to do this in xen_arch_setup, but that is too late
@@ -1332,13 +1302,6 @@ asmlinkage __visible void __init xen_start_kernel(void)
if (rc != 0)
xen_raw_printk("physdev_op failed %d\n", rc);

-#ifdef CONFIG_X86_32
- /* set up basic CPUID stuff */
- cpu_detect(&new_cpu_data);
- set_cpu_cap(&new_cpu_data, X86_FEATURE_FPU);
- new_cpu_data.x86_capability[CPUID_1_EDX] = cpuid_edx(1);
-#endif
-
if (xen_start_info->mod_start) {
if (xen_start_info->flags & SIF_MOD_START_PFN)
initrd_start = PFN_PHYS(xen_start_info->mod_start);
@@ -1406,12 +1369,8 @@ asmlinkage __visible void __init xen_start_kernel(void)
xen_efi_init(&boot_params);

/* Start the world */
-#ifdef CONFIG_X86_32
- i386_start_kernel();
-#else
cr4_init_shadow(); /* 32b kernel does this in i386_start_kernel() */
x86_64_start_reservations((char *)__pa_symbol(&boot_params));
-#endif
}

static int xen_cpu_up_prepare_pv(unsigned int cpu)
diff --git a/arch/x86/xen/mmu_pv.c b/arch/x86/xen/mmu_pv.c
index beb44e22afdf..d6718782b123 100644
--- a/arch/x86/xen/mmu_pv.c
+++ b/arch/x86/xen/mmu_pv.c
@@ -86,19 +86,8 @@
#include "mmu.h"
#include "debugfs.h"

-#ifdef CONFIG_X86_32
-/*
- * Identity map, in addition to plain kernel map. This needs to be
- * large enough to allocate page table pages to allocate the rest.
- * Each page can map 2MB.
- */
-#define LEVEL1_IDENT_ENTRIES (PTRS_PER_PTE * 4)
-static RESERVE_BRK_ARRAY(pte_t, level1_ident_pgt, LEVEL1_IDENT_ENTRIES);
-#endif
-#ifdef CONFIG_X86_64
/* l3 pud for userspace vsyscall mapping */
static pud_t level3_user_vsyscall[PTRS_PER_PUD] __page_aligned_bss;
-#endif /* CONFIG_X86_64 */

/*
* Protects atomic reservation decrease/increase against concurrent increases.
@@ -439,26 +428,6 @@ static void xen_set_pud(pud_t *ptr, pud_t val)
xen_set_pud_hyper(ptr, val);
}

-#ifdef CONFIG_X86_PAE
-static void xen_set_pte_atomic(pte_t *ptep, pte_t pte)
-{
- trace_xen_mmu_set_pte_atomic(ptep, pte);
- __xen_set_pte(ptep, pte);
-}
-
-static void xen_pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
-{
- trace_xen_mmu_pte_clear(mm, addr, ptep);
- __xen_set_pte(ptep, native_make_pte(0));
-}
-
-static void xen_pmd_clear(pmd_t *pmdp)
-{
- trace_xen_mmu_pmd_clear(pmdp);
- set_pmd(pmdp, __pmd(0));
-}
-#endif /* CONFIG_X86_PAE */
-
__visible pmd_t xen_make_pmd(pmdval_t pmd)
{
pmd = pte_pfn_to_mfn(pmd);
@@ -466,7 +435,6 @@ __visible pmd_t xen_make_pmd(pmdval_t pmd)
}
PV_CALLEE_SAVE_REGS_THUNK(xen_make_pmd);

-#ifdef CONFIG_X86_64
__visible pudval_t xen_pud_val(pud_t pud)
{
return pte_mfn_to_pfn(pud.pud);
@@ -571,7 +539,6 @@ __visible p4d_t xen_make_p4d(p4dval_t p4d)
}
PV_CALLEE_SAVE_REGS_THUNK(xen_make_p4d);
#endif /* CONFIG_PGTABLE_LEVELS >= 5 */
-#endif /* CONFIG_X86_64 */

static int xen_pmd_walk(struct mm_struct *mm, pmd_t *pmd,
int (*func)(struct mm_struct *mm, struct page *, enum pt_level),
@@ -654,14 +621,12 @@ static int __xen_pgd_walk(struct mm_struct *mm, pgd_t *pgd,
limit--;
BUG_ON(limit >= FIXADDR_TOP);

-#ifdef CONFIG_X86_64
/*
* 64-bit has a great big hole in the middle of the address
* space, which contains the Xen mappings.
*/
hole_low = pgd_index(GUARD_HOLE_BASE_ADDR);
hole_high = pgd_index(GUARD_HOLE_END_ADDR);
-#endif

nr = pgd_index(limit) + 1;
for (i = 0; i < nr; i++) {
@@ -800,7 +765,6 @@ static void __xen_pgd_pin(struct mm_struct *mm, pgd_t *pgd)
xen_mc_batch();
}

-#ifdef CONFIG_X86_64
{
pgd_t *user_pgd = xen_get_user_pgd(pgd);

@@ -812,14 +776,6 @@ static void __xen_pgd_pin(struct mm_struct *mm, pgd_t *pgd)
PFN_DOWN(__pa(user_pgd)));
}
}
-#else /* CONFIG_X86_32 */
-#ifdef CONFIG_X86_PAE
- /* Need to make sure unshared kernel PMD is pinnable */
- xen_pin_page(mm, pgd_page(pgd[pgd_index(TASK_SIZE)]),
- PT_PMD);
-#endif
- xen_do_pin(MMUEXT_PIN_L3_TABLE, PFN_DOWN(__pa(pgd)));
-#endif /* CONFIG_X86_64 */
xen_mc_issue(0);
}

@@ -870,9 +826,7 @@ static int __init xen_mark_pinned(struct mm_struct *mm, struct page *page,
static void __init xen_after_bootmem(void)
{
static_branch_enable(&xen_struct_pages_ready);
-#ifdef CONFIG_X86_64
SetPagePinned(virt_to_page(level3_user_vsyscall));
-#endif
xen_pgd_walk(&init_mm, xen_mark_pinned, FIXADDR_TOP);
}

@@ -919,29 +873,18 @@ static int xen_unpin_page(struct mm_struct *mm, struct page *page,
/* Release a pagetables pages back as normal RW */
static void __xen_pgd_unpin(struct mm_struct *mm, pgd_t *pgd)
{
+ pgd_t *user_pgd = xen_get_user_pgd(pgd);
+
trace_xen_mmu_pgd_unpin(mm, pgd);

xen_mc_batch();

xen_do_pin(MMUEXT_UNPIN_TABLE, PFN_DOWN(__pa(pgd)));

-#ifdef CONFIG_X86_64
- {
- pgd_t *user_pgd = xen_get_user_pgd(pgd);
-
- if (user_pgd) {
- xen_do_pin(MMUEXT_UNPIN_TABLE,
- PFN_DOWN(__pa(user_pgd)));
- xen_unpin_page(mm, virt_to_page(user_pgd), PT_PGD);
- }
+ if (user_pgd) {
+ xen_do_pin(MMUEXT_UNPIN_TABLE, PFN_DOWN(__pa(user_pgd)));
+ xen_unpin_page(mm, virt_to_page(user_pgd), PT_PGD);
}
-#endif
-
-#ifdef CONFIG_X86_PAE
- /* Need to make sure unshared kernel PMD is unpinned */
- xen_unpin_page(mm, pgd_page(pgd[pgd_index(TASK_SIZE)]),
- PT_PMD);
-#endif

__xen_pgd_walk(mm, pgd, xen_unpin_page, USER_LIMIT);

@@ -1089,7 +1032,6 @@ static void __init pin_pagetable_pfn(unsigned cmd, unsigned long pfn)
BUG();
}

-#ifdef CONFIG_X86_64
static void __init xen_cleanhighmap(unsigned long vaddr,
unsigned long vaddr_end)
{
@@ -1273,17 +1215,15 @@ static void __init xen_pagetable_cleanhighmap(void)
xen_cleanhighmap(addr, roundup(addr + size, PMD_SIZE * 2));
xen_start_info->pt_base = (unsigned long)__va(__pa(xen_start_info->pt_base));
}
-#endif

static void __init xen_pagetable_p2m_setup(void)
{
xen_vmalloc_p2m_tree();

-#ifdef CONFIG_X86_64
xen_pagetable_p2m_free();

xen_pagetable_cleanhighmap();
-#endif
+
/* And revector! Bye bye old array */
xen_start_info->mfn_list = (unsigned long)xen_p2m_addr;
}
@@ -1430,6 +1370,8 @@ static void __xen_write_cr3(bool kernel, unsigned long cr3)
}
static void xen_write_cr3(unsigned long cr3)
{
+ pgd_t *user_pgd = xen_get_user_pgd(__va(cr3));
+
BUG_ON(preemptible());

xen_mc_batch(); /* disables interrupts */
@@ -1440,20 +1382,14 @@ static void xen_write_cr3(unsigned long cr3)

__xen_write_cr3(true, cr3);

-#ifdef CONFIG_X86_64
- {
- pgd_t *user_pgd = xen_get_user_pgd(__va(cr3));
- if (user_pgd)
- __xen_write_cr3(false, __pa(user_pgd));
- else
- __xen_write_cr3(false, 0);
- }
-#endif
+ if (user_pgd)
+ __xen_write_cr3(false, __pa(user_pgd));
+ else
+ __xen_write_cr3(false, 0);

xen_mc_issue(PARAVIRT_LAZY_CPU); /* interrupts restored */
}

-#ifdef CONFIG_X86_64
/*
* At the start of the day - when Xen launches a guest, it has already
* built pagetables for the guest. We diligently look over them
@@ -1488,49 +1424,39 @@ static void __init xen_write_cr3_init(unsigned long cr3)

xen_mc_issue(PARAVIRT_LAZY_CPU); /* interrupts restored */
}
-#endif

static int xen_pgd_alloc(struct mm_struct *mm)
{
pgd_t *pgd = mm->pgd;
- int ret = 0;
+ int ret = -ENOMEM;
+ struct page *page = virt_to_page(pgd);
+ pgd_t *user_pgd;

BUG_ON(PagePinned(virt_to_page(pgd)));
+ BUG_ON(page->private != 0);

-#ifdef CONFIG_X86_64
- {
- struct page *page = virt_to_page(pgd);
- pgd_t *user_pgd;
-
- BUG_ON(page->private != 0);
-
- ret = -ENOMEM;
-
- user_pgd = (pgd_t *)__get_free_page(GFP_KERNEL | __GFP_ZERO);
- page->private = (unsigned long)user_pgd;
+ user_pgd = (pgd_t *)__get_free_page(GFP_KERNEL | __GFP_ZERO);
+ page->private = (unsigned long)user_pgd;

- if (user_pgd != NULL) {
+ if (user_pgd != NULL) {
#ifdef CONFIG_X86_VSYSCALL_EMULATION
- user_pgd[pgd_index(VSYSCALL_ADDR)] =
- __pgd(__pa(level3_user_vsyscall) | _PAGE_TABLE);
+ user_pgd[pgd_index(VSYSCALL_ADDR)] =
+ __pgd(__pa(level3_user_vsyscall) | _PAGE_TABLE);
#endif
- ret = 0;
- }
-
- BUG_ON(PagePinned(virt_to_page(xen_get_user_pgd(pgd))));
+ ret = 0;
}
-#endif
+
+ BUG_ON(PagePinned(virt_to_page(xen_get_user_pgd(pgd))));
+
return ret;
}

static void xen_pgd_free(struct mm_struct *mm, pgd_t *pgd)
{
-#ifdef CONFIG_X86_64
pgd_t *user_pgd = xen_get_user_pgd(pgd);

if (user_pgd)
free_page((unsigned long)user_pgd);
-#endif
}

/*
@@ -1549,7 +1475,6 @@ static void xen_pgd_free(struct mm_struct *mm, pgd_t *pgd)
*/
__visible pte_t xen_make_pte_init(pteval_t pte)
{
-#ifdef CONFIG_X86_64
unsigned long pfn;

/*
@@ -1563,7 +1488,7 @@ __visible pte_t xen_make_pte_init(pteval_t pte)
pfn >= xen_start_info->first_p2m_pfn &&
pfn < xen_start_info->first_p2m_pfn + xen_start_info->nr_p2m_frames)
pte &= ~_PAGE_RW;
-#endif
+
pte = pte_pfn_to_mfn(pte);
return native_make_pte(pte);
}
@@ -1571,13 +1496,6 @@ PV_CALLEE_SAVE_REGS_THUNK(xen_make_pte_init);

static void __init xen_set_pte_init(pte_t *ptep, pte_t pte)
{
-#ifdef CONFIG_X86_32
- /* If there's an existing pte, then don't allow _PAGE_RW to be set */
- if (pte_mfn(pte) != INVALID_P2M_ENTRY
- && pte_val_ma(*ptep) & _PAGE_PRESENT)
- pte = __pte_ma(((pte_val_ma(*ptep) & _PAGE_RW) | ~_PAGE_RW) &
- pte_val_ma(pte));
-#endif
__xen_set_pte(ptep, pte);
}

@@ -1712,7 +1630,6 @@ static void xen_release_pmd(unsigned long pfn)
xen_release_ptpage(pfn, PT_PMD);
}

-#ifdef CONFIG_X86_64
static void xen_alloc_pud(struct mm_struct *mm, unsigned long pfn)
{
xen_alloc_ptpage(mm, pfn, PT_PUD);
@@ -1722,20 +1639,6 @@ static void xen_release_pud(unsigned long pfn)
{
xen_release_ptpage(pfn, PT_PUD);
}
-#endif
-
-void __init xen_reserve_top(void)
-{
-#ifdef CONFIG_X86_32
- unsigned long top = HYPERVISOR_VIRT_START;
- struct xen_platform_parameters pp;
-
- if (HYPERVISOR_xen_version(XENVER_platform_parameters, &pp) == 0)
- top = pp.virt_start;
-
- reserve_top_address(-top);
-#endif /* CONFIG_X86_32 */
-}

/*
* Like __va(), but returns address in the kernel mapping (which is
@@ -1743,11 +1646,7 @@ void __init xen_reserve_top(void)
*/
static void * __init __ka(phys_addr_t paddr)
{
-#ifdef CONFIG_X86_64
return (void *)(paddr + __START_KERNEL_map);
-#else
- return __va(paddr);
-#endif
}

/* Convert a machine address to physical address */
@@ -1781,56 +1680,7 @@ static void __init set_page_prot(void *addr, pgprot_t prot)
{
return set_page_prot_flags(addr, prot, UVMF_NONE);
}
-#ifdef CONFIG_X86_32
-static void __init xen_map_identity_early(pmd_t *pmd, unsigned long max_pfn)
-{
- unsigned pmdidx, pteidx;
- unsigned ident_pte;
- unsigned long pfn;
-
- level1_ident_pgt = extend_brk(sizeof(pte_t) * LEVEL1_IDENT_ENTRIES,
- PAGE_SIZE);
-
- ident_pte = 0;
- pfn = 0;
- for (pmdidx = 0; pmdidx < PTRS_PER_PMD && pfn < max_pfn; pmdidx++) {
- pte_t *pte_page;
-
- /* Reuse or allocate a page of ptes */
- if (pmd_present(pmd[pmdidx]))
- pte_page = m2v(pmd[pmdidx].pmd);
- else {
- /* Check for free pte pages */
- if (ident_pte == LEVEL1_IDENT_ENTRIES)
- break;
-
- pte_page = &level1_ident_pgt[ident_pte];
- ident_pte += PTRS_PER_PTE;
-
- pmd[pmdidx] = __pmd(__pa(pte_page) | _PAGE_TABLE);
- }
-
- /* Install mappings */
- for (pteidx = 0; pteidx < PTRS_PER_PTE; pteidx++, pfn++) {
- pte_t pte;
-
- if (pfn > max_pfn_mapped)
- max_pfn_mapped = pfn;
-
- if (!pte_none(pte_page[pteidx]))
- continue;
-
- pte = pfn_pte(pfn, PAGE_KERNEL_EXEC);
- pte_page[pteidx] = pte;
- }
- }

- for (pteidx = 0; pteidx < ident_pte; pteidx += PTRS_PER_PTE)
- set_page_prot(&level1_ident_pgt[pteidx], PAGE_KERNEL_RO);
-
- set_page_prot(pmd, PAGE_KERNEL_RO);
-}
-#endif
void __init xen_setup_machphys_mapping(void)
{
struct xen_machphys_mapping mapping;
@@ -1841,13 +1691,8 @@ void __init xen_setup_machphys_mapping(void)
} else {
machine_to_phys_nr = MACH2PHYS_NR_ENTRIES;
}
-#ifdef CONFIG_X86_32
- WARN_ON((machine_to_phys_mapping + (machine_to_phys_nr - 1))
- < machine_to_phys_mapping);
-#endif
}

-#ifdef CONFIG_X86_64
static void __init convert_pfn_mfn(void *v)
{
pte_t *pte = v;
@@ -2178,105 +2023,6 @@ void __init xen_relocate_p2m(void)
xen_start_info->nr_p2m_frames = n_frames;
}

-#else /* !CONFIG_X86_64 */
-static RESERVE_BRK_ARRAY(pmd_t, initial_kernel_pmd, PTRS_PER_PMD);
-static RESERVE_BRK_ARRAY(pmd_t, swapper_kernel_pmd, PTRS_PER_PMD);
-RESERVE_BRK(fixup_kernel_pmd, PAGE_SIZE);
-RESERVE_BRK(fixup_kernel_pte, PAGE_SIZE);
-
-static void __init xen_write_cr3_init(unsigned long cr3)
-{
- unsigned long pfn = PFN_DOWN(__pa(swapper_pg_dir));
-
- BUG_ON(read_cr3_pa() != __pa(initial_page_table));
- BUG_ON(cr3 != __pa(swapper_pg_dir));
-
- /*
- * We are switching to swapper_pg_dir for the first time (from
- * initial_page_table) and therefore need to mark that page
- * read-only and then pin it.
- *
- * Xen disallows sharing of kernel PMDs for PAE
- * guests. Therefore we must copy the kernel PMD from
- * initial_page_table into a new kernel PMD to be used in
- * swapper_pg_dir.
- */
- swapper_kernel_pmd =
- extend_brk(sizeof(pmd_t) * PTRS_PER_PMD, PAGE_SIZE);
- copy_page(swapper_kernel_pmd, initial_kernel_pmd);
- swapper_pg_dir[KERNEL_PGD_BOUNDARY] =
- __pgd(__pa(swapper_kernel_pmd) | _PAGE_PRESENT);
- set_page_prot(swapper_kernel_pmd, PAGE_KERNEL_RO);
-
- set_page_prot(swapper_pg_dir, PAGE_KERNEL_RO);
- xen_write_cr3(cr3);
- pin_pagetable_pfn(MMUEXT_PIN_L3_TABLE, pfn);
-
- pin_pagetable_pfn(MMUEXT_UNPIN_TABLE,
- PFN_DOWN(__pa(initial_page_table)));
- set_page_prot(initial_page_table, PAGE_KERNEL);
- set_page_prot(initial_kernel_pmd, PAGE_KERNEL);
-
- pv_ops.mmu.write_cr3 = &xen_write_cr3;
-}
-
-/*
- * For 32 bit domains xen_start_info->pt_base is the pgd address which might be
- * not the first page table in the page table pool.
- * Iterate through the initial page tables to find the real page table base.
- */
-static phys_addr_t __init xen_find_pt_base(pmd_t *pmd)
-{
- phys_addr_t pt_base, paddr;
- unsigned pmdidx;
-
- pt_base = min(__pa(xen_start_info->pt_base), __pa(pmd));
-
- for (pmdidx = 0; pmdidx < PTRS_PER_PMD; pmdidx++)
- if (pmd_present(pmd[pmdidx]) && !pmd_large(pmd[pmdidx])) {
- paddr = m2p(pmd[pmdidx].pmd);
- pt_base = min(pt_base, paddr);
- }
-
- return pt_base;
-}
-
-void __init xen_setup_kernel_pagetable(pgd_t *pgd, unsigned long max_pfn)
-{
- pmd_t *kernel_pmd;
-
- kernel_pmd = m2v(pgd[KERNEL_PGD_BOUNDARY].pgd);
-
- xen_pt_base = xen_find_pt_base(kernel_pmd);
- xen_pt_size = xen_start_info->nr_pt_frames * PAGE_SIZE;
-
- initial_kernel_pmd =
- extend_brk(sizeof(pmd_t) * PTRS_PER_PMD, PAGE_SIZE);
-
- max_pfn_mapped = PFN_DOWN(xen_pt_base + xen_pt_size + 512 * 1024);
-
- copy_page(initial_kernel_pmd, kernel_pmd);
-
- xen_map_identity_early(initial_kernel_pmd, max_pfn);
-
- copy_page(initial_page_table, pgd);
- initial_page_table[KERNEL_PGD_BOUNDARY] =
- __pgd(__pa(initial_kernel_pmd) | _PAGE_PRESENT);
-
- set_page_prot(initial_kernel_pmd, PAGE_KERNEL_RO);
- set_page_prot(initial_page_table, PAGE_KERNEL_RO);
- set_page_prot(empty_zero_page, PAGE_KERNEL_RO);
-
- pin_pagetable_pfn(MMUEXT_UNPIN_TABLE, PFN_DOWN(__pa(pgd)));
-
- pin_pagetable_pfn(MMUEXT_PIN_L3_TABLE,
- PFN_DOWN(__pa(initial_page_table)));
- xen_write_cr3(__pa(initial_page_table));
-
- memblock_reserve(xen_pt_base, xen_pt_size);
-}
-#endif /* CONFIG_X86_64 */
-
void __init xen_reserve_special_pages(void)
{
phys_addr_t paddr;
@@ -2310,12 +2056,7 @@ static void xen_set_fixmap(unsigned idx, phys_addr_t phys, pgprot_t prot)

switch (idx) {
case FIX_BTMAP_END ... FIX_BTMAP_BEGIN:
-#ifdef CONFIG_X86_32
- case FIX_WP_TEST:
-# ifdef CONFIG_HIGHMEM
- case FIX_KMAP_BEGIN ... FIX_KMAP_END:
-# endif
-#elif defined(CONFIG_X86_VSYSCALL_EMULATION)
+#if defined(CONFIG_X86_VSYSCALL_EMULATION)
case VSYSCALL_PAGE:
#endif
/* All local page mappings */
@@ -2367,9 +2108,7 @@ static void __init xen_post_allocator_init(void)
pv_ops.mmu.set_pte = xen_set_pte;
pv_ops.mmu.set_pmd = xen_set_pmd;
pv_ops.mmu.set_pud = xen_set_pud;
-#ifdef CONFIG_X86_64
pv_ops.mmu.set_p4d = xen_set_p4d;
-#endif

/* This will work as long as patching hasn't happened yet
(which it hasn't) */
@@ -2377,15 +2116,11 @@ static void __init xen_post_allocator_init(void)
pv_ops.mmu.alloc_pmd = xen_alloc_pmd;
pv_ops.mmu.release_pte = xen_release_pte;
pv_ops.mmu.release_pmd = xen_release_pmd;
-#ifdef CONFIG_X86_64
pv_ops.mmu.alloc_pud = xen_alloc_pud;
pv_ops.mmu.release_pud = xen_release_pud;
-#endif
pv_ops.mmu.make_pte = PV_CALLEE_SAVE(xen_make_pte);

-#ifdef CONFIG_X86_64
pv_ops.mmu.write_cr3 = &xen_write_cr3;
-#endif
}

static void xen_leave_lazy_mmu(void)
@@ -2430,17 +2165,11 @@ static const struct pv_mmu_ops xen_mmu_ops __initconst = {
.make_pte = PV_CALLEE_SAVE(xen_make_pte_init),
.make_pgd = PV_CALLEE_SAVE(xen_make_pgd),

-#ifdef CONFIG_X86_PAE
- .set_pte_atomic = xen_set_pte_atomic,
- .pte_clear = xen_pte_clear,
- .pmd_clear = xen_pmd_clear,
-#endif /* CONFIG_X86_PAE */
.set_pud = xen_set_pud_hyper,

.make_pmd = PV_CALLEE_SAVE(xen_make_pmd),
.pmd_val = PV_CALLEE_SAVE(xen_pmd_val),

-#ifdef CONFIG_X86_64
.pud_val = PV_CALLEE_SAVE(xen_pud_val),
.make_pud = PV_CALLEE_SAVE(xen_make_pud),
.set_p4d = xen_set_p4d_hyper,
@@ -2452,7 +2181,6 @@ static const struct pv_mmu_ops xen_mmu_ops __initconst = {
.p4d_val = PV_CALLEE_SAVE(xen_p4d_val),
.make_p4d = PV_CALLEE_SAVE(xen_make_p4d),
#endif
-#endif /* CONFIG_X86_64 */

.activate_mm = xen_activate_mm,
.dup_mmap = xen_dup_mmap,
diff --git a/arch/x86/xen/p2m.c b/arch/x86/xen/p2m.c
index 95ce9b5be411..a6cd2936d214 100644
--- a/arch/x86/xen/p2m.c
+++ b/arch/x86/xen/p2m.c
@@ -379,12 +379,8 @@ static void __init xen_rebuild_p2m_list(unsigned long *p2m)

if (type == P2M_TYPE_PFN || i < chunk) {
/* Use initial p2m page contents. */
-#ifdef CONFIG_X86_64
mfns = alloc_p2m_page();
copy_page(mfns, xen_p2m_addr + pfn);
-#else
- mfns = xen_p2m_addr + pfn;
-#endif
ptep = populate_extra_pte((unsigned long)(p2m + pfn));
set_pte(ptep,
pfn_pte(PFN_DOWN(__pa(mfns)), PAGE_KERNEL));
diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c
index 548d1e0a5ba1..ff401026ad84 100644
--- a/arch/x86/xen/setup.c
+++ b/arch/x86/xen/setup.c
@@ -544,13 +544,10 @@ static unsigned long __init xen_get_pages_limit(void)
{
unsigned long limit;

-#ifdef CONFIG_X86_32
- limit = GB(64) / PAGE_SIZE;
-#else
limit = MAXMEM / PAGE_SIZE;
if (!xen_initial_domain() && xen_512gb_limit)
limit = GB(512) / PAGE_SIZE;
-#endif
+
return limit;
}

@@ -721,17 +718,8 @@ static void __init xen_reserve_xen_mfnlist(void)
if (!xen_is_e820_reserved(start, size))
return;

-#ifdef CONFIG_X86_32
- /*
- * Relocating the p2m on 32 bit system to an arbitrary virtual address
- * is not supported, so just give up.
- */
- xen_raw_console_write("Xen hypervisor allocated p2m list conflicts with E820 map\n");
- BUG();
-#else
xen_relocate_p2m();
memblock_free(start, size);
-#endif
}

/**
@@ -920,20 +908,6 @@ char * __init xen_memory_setup(void)
return "Xen";
}

-/*
- * Set the bit indicating "nosegneg" library variants should be used.
- * We only need to bother in pure 32-bit mode; compat 32-bit processes
- * can have un-truncated segments, so wrapping around is allowed.
- */
-static void __init fiddle_vdso(void)
-{
-#ifdef CONFIG_X86_32
- u32 *mask = vdso_image_32.data +
- vdso_image_32.sym_VDSO32_NOTE_MASK;
- *mask |= 1 << VDSO_NOTE_NONEGSEG_BIT;
-#endif
-}
-
static int register_callback(unsigned type, const void *func)
{
struct callback_register callback = {
@@ -948,25 +922,17 @@ static int register_callback(unsigned type, const void *func)
void xen_enable_sysenter(void)
{
int ret;
- unsigned sysenter_feature;
-
-#ifdef CONFIG_X86_32
- sysenter_feature = X86_FEATURE_SEP;
-#else
- sysenter_feature = X86_FEATURE_SYSENTER32;
-#endif

- if (!boot_cpu_has(sysenter_feature))
+ if (!boot_cpu_has(X86_FEATURE_SYSENTER32))
return;

ret = register_callback(CALLBACKTYPE_sysenter, xen_sysenter_target);
- if(ret != 0)
- setup_clear_cpu_cap(sysenter_feature);
+ if (ret != 0)
+ setup_clear_cpu_cap(X86_FEATURE_SYSENTER32);
}

void xen_enable_syscall(void)
{
-#ifdef CONFIG_X86_64
int ret;

ret = register_callback(CALLBACKTYPE_syscall, xen_syscall_target);
@@ -982,7 +948,6 @@ void xen_enable_syscall(void)
if (ret != 0)
setup_clear_cpu_cap(X86_FEATURE_SYSCALL32);
}
-#endif /* CONFIG_X86_64 */
}

void __init xen_pvmmu_arch_setup(void)
@@ -1022,7 +987,6 @@ void __init xen_arch_setup(void)
disable_cpuidle();
disable_cpufreq();
WARN_ON(xen_set_default_idle());
- fiddle_vdso();
#ifdef CONFIG_NUMA
numa_off = 1;
#endif
diff --git a/arch/x86/xen/smp_pv.c b/arch/x86/xen/smp_pv.c
index 590fcf863006..20977a242003 100644
--- a/arch/x86/xen/smp_pv.c
+++ b/arch/x86/xen/smp_pv.c
@@ -208,15 +208,6 @@ static void __init xen_pv_smp_prepare_boot_cpu(void)
* sure the old memory can be recycled. */
make_lowmem_page_readwrite(xen_initial_gdt);

-#ifdef CONFIG_X86_32
- /*
- * Xen starts us with XEN_FLAT_RING1_DS, but linux code
- * expects __USER_DS
- */
- loadsegment(ds, __USER_DS);
- loadsegment(es, __USER_DS);
-#endif
-
xen_filter_cpu_maps();
xen_setup_vcpu_info_placement();

@@ -296,10 +287,6 @@ cpu_initialize_context(unsigned int cpu, struct task_struct *idle)

gdt = get_cpu_gdt_rw(cpu);

-#ifdef CONFIG_X86_32
- ctxt->user_regs.fs = __KERNEL_PERCPU;
- ctxt->user_regs.gs = __KERNEL_STACK_CANARY;
-#endif
memset(&ctxt->fpu_ctxt, 0, sizeof(ctxt->fpu_ctxt));

/*
@@ -337,12 +324,8 @@ cpu_initialize_context(unsigned int cpu, struct task_struct *idle)
ctxt->kernel_ss = __KERNEL_DS;
ctxt->kernel_sp = task_top_of_stack(idle);

-#ifdef CONFIG_X86_32
- ctxt->event_callback_cs = __KERNEL_CS;
- ctxt->failsafe_callback_cs = __KERNEL_CS;
-#else
ctxt->gs_base_kernel = per_cpu_offset(cpu);
-#endif
+
ctxt->event_callback_eip =
(unsigned long)xen_hypervisor_callback;
ctxt->failsafe_callback_eip =
diff --git a/arch/x86/xen/xen-asm.S b/arch/x86/xen/xen-asm.S
index 8019edd0125c..54e1e9ca35a4 100644
--- a/arch/x86/xen/xen-asm.S
+++ b/arch/x86/xen/xen-asm.S
@@ -75,11 +75,7 @@ ENTRY(xen_save_fl_direct)
*/
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 with any
@@ -103,15 +99,6 @@ ENTRY(xen_restore_fl_direct)
*/
ENTRY(check_events)
FRAME_BEGIN
-#ifdef CONFIG_X86_32
- push %eax
- push %ecx
- push %edx
- call xen_force_evtchn_callback
- pop %edx
- pop %ecx
- pop %eax
-#else
push %rax
push %rcx
push %rdx
@@ -131,7 +118,6 @@ ENTRY(check_events)
pop %rdx
pop %rcx
pop %rax
-#endif
FRAME_END
ret
ENDPROC(check_events)
diff --git a/arch/x86/xen/xen-asm_32.S b/arch/x86/xen/xen-asm_32.S
deleted file mode 100644
index c15db060a242..000000000000
--- a/arch/x86/xen/xen-asm_32.S
+++ /dev/null
@@ -1,207 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-/*
- * Asm versions of Xen pv-ops, suitable for direct use.
- *
- * We only bother with direct forms (ie, vcpu in pda) of the
- * operations here; the indirect forms are better handled in C.
- */
-
-#include <asm/thread_info.h>
-#include <asm/processor-flags.h>
-#include <asm/segment.h>
-#include <asm/asm.h>
-
-#include <xen/interface/xen.h>
-
-#include <linux/linkage.h>
-
-/* Pseudo-flag used for virtual NMI, which we don't implement yet */
-#define XEN_EFLAGS_NMI 0x80000000
-
-/*
- * This is run where a normal iret would be run, with the same stack setup:
- * 8: eflags
- * 4: cs
- * esp-> 0: eip
- *
- * This attempts to make sure that any pending events are dealt with
- * on return to usermode, but there is a small window in which an
- * event can happen just before entering usermode. If the nested
- * interrupt ends up setting one of the TIF_WORK_MASK pending work
- * flags, they will not be tested again before returning to
- * usermode. This means that a process can end up with pending work,
- * which will be unprocessed until the process enters and leaves the
- * kernel again, which could be an unbounded amount of time. This
- * means that a pending signal or reschedule event could be
- * indefinitely delayed.
- *
- * The fix is to notice a nested interrupt in the critical window, and
- * if one occurs, then fold the nested interrupt into the current
- * interrupt stack frame, and re-process it iteratively rather than
- * recursively. This means that it will exit via the normal path, and
- * all pending work will be dealt with appropriately.
- *
- * Because the nested interrupt handler needs to deal with the current
- * stack state in whatever form its in, we keep things simple by only
- * using a single register which is pushed/popped on the stack.
- */
-
-.macro POP_FS
-1:
- popw %fs
-.pushsection .fixup, "ax"
-2: movw $0, (%esp)
- jmp 1b
-.popsection
- _ASM_EXTABLE(1b,2b)
-.endm
-
-ENTRY(xen_iret)
- /* test eflags for special cases */
- testl $(X86_EFLAGS_VM | XEN_EFLAGS_NMI), 8(%esp)
- jnz hyper_iret
-
- push %eax
- ESP_OFFSET=4 # bytes pushed onto stack
-
- /* Store vcpu_info pointer for easy access */
-#ifdef CONFIG_SMP
- pushw %fs
- movl $(__KERNEL_PERCPU), %eax
- movl %eax, %fs
- movl %fs:xen_vcpu, %eax
- POP_FS
-#else
- movl %ss:xen_vcpu, %eax
-#endif
-
- /* check IF state we're restoring */
- testb $X86_EFLAGS_IF>>8, 8+1+ESP_OFFSET(%esp)
-
- /*
- * Maybe enable events. Once this happens we could get a
- * recursive event, so the critical region starts immediately
- * afterwards. However, if that happens we don't end up
- * resuming the code, so we don't have to be worried about
- * being preempted to another CPU.
- */
- setz %ss:XEN_vcpu_info_mask(%eax)
-xen_iret_start_crit:
-
- /* check for unmasked and pending */
- cmpw $0x0001, %ss:XEN_vcpu_info_pending(%eax)
-
- /*
- * If there's something pending, mask events again so we can
- * jump back into xen_hypervisor_callback. Otherwise do not
- * touch XEN_vcpu_info_mask.
- */
- jne 1f
- movb $1, %ss:XEN_vcpu_info_mask(%eax)
-
-1: popl %eax
-
- /*
- * From this point on the registers are restored and the stack
- * updated, so we don't need to worry about it if we're
- * preempted
- */
-iret_restore_end:
-
- /*
- * Jump to hypervisor_callback after fixing up the stack.
- * Events are masked, so jumping out of the critical region is
- * OK.
- */
- je xen_hypervisor_callback
-
-1: iret
-xen_iret_end_crit:
- _ASM_EXTABLE(1b, iret_exc)
-
-hyper_iret:
- /* put this out of line since its very rarely used */
- jmp hypercall_page + __HYPERVISOR_iret * 32
-
- .globl xen_iret_start_crit, xen_iret_end_crit
-
-/*
- * This is called by xen_hypervisor_callback in entry.S when it sees
- * that the EIP at the time of interrupt was between
- * xen_iret_start_crit and xen_iret_end_crit. We're passed the EIP in
- * %eax so we can do a more refined determination of what to do.
- *
- * The stack format at this point is:
- * ----------------
- * ss : (ss/esp may be present if we came from usermode)
- * esp :
- * eflags } outer exception info
- * cs }
- * eip }
- * ---------------- <- edi (copy dest)
- * eax : outer eax if it hasn't been restored
- * ----------------
- * eflags } nested exception info
- * cs } (no ss/esp because we're nested
- * eip } from the same ring)
- * orig_eax }<- esi (copy src)
- * - - - - - - - -
- * fs }
- * es }
- * ds } SAVE_ALL state
- * eax }
- * : :
- * ebx }<- esp
- * ----------------
- *
- * In order to deliver the nested exception properly, we need to shift
- * everything from the return addr up to the error code so it sits
- * just under the outer exception info. This means that when we
- * handle the exception, we do it in the context of the outer
- * exception rather than starting a new one.
- *
- * The only caveat is that if the outer eax hasn't been restored yet
- * (ie, it's still on stack), we need to insert its value into the
- * SAVE_ALL state before going on, since it's usermode state which we
- * eventually need to restore.
- */
-ENTRY(xen_iret_crit_fixup)
- /*
- * Paranoia: Make sure we're really coming from kernel space.
- * One could imagine a case where userspace jumps into the
- * critical range address, but just before the CPU delivers a
- * GP, it decides to deliver an interrupt instead. Unlikely?
- * Definitely. Easy to avoid? Yes. The Intel documents
- * explicitly say that the reported EIP for a bad jump is the
- * jump instruction itself, not the destination, but some
- * virtual environments get this wrong.
- */
- movl PT_CS(%esp), %ecx
- andl $SEGMENT_RPL_MASK, %ecx
- cmpl $USER_RPL, %ecx
- je 2f
-
- lea PT_ORIG_EAX(%esp), %esi
- lea PT_EFLAGS(%esp), %edi
-
- /*
- * If eip is before iret_restore_end then stack
- * hasn't been restored yet.
- */
- cmp $iret_restore_end, %eax
- jae 1f
-
- movl 0+4(%edi), %eax /* copy EAX (just above top of frame) */
- movl %eax, PT_EAX(%esp)
-
- lea ESP_OFFSET(%edi), %edi /* move dest up over saved regs */
-
- /* set up the copy */
-1: std
- mov $PT_EIP / 4, %ecx /* saved regs up to orig_eax */
- rep movsl
- cld
-
- lea 4(%edi), %esp /* point esp to new frame */
-2: jmp xen_do_upcall
-
diff --git a/arch/x86/xen/xen-head.S b/arch/x86/xen/xen-head.S
index c1d8b90aa4e2..03a7af6b7453 100644
--- a/arch/x86/xen/xen-head.S
+++ b/arch/x86/xen/xen-head.S
@@ -37,7 +37,6 @@ ENTRY(startup_xen)
mov %_ASM_SI, xen_start_info
mov $init_thread_union+THREAD_SIZE, %_ASM_SP

-#ifdef CONFIG_X86_64
/* Set up %gs.
*
* The base of %gs always points to fixed_percpu_data. If the
@@ -49,7 +48,6 @@ ENTRY(startup_xen)
movq $INIT_PER_CPU_VAR(fixed_percpu_data),%rax
cdq
wrmsr
-#endif

jmp xen_start_kernel
END(startup_xen)
@@ -75,13 +73,9 @@ END(hypercall_page)
ELFNOTE(Xen, XEN_ELFNOTE_GUEST_OS, .asciz "linux")
ELFNOTE(Xen, XEN_ELFNOTE_GUEST_VERSION, .asciz "2.6")
ELFNOTE(Xen, XEN_ELFNOTE_XEN_VERSION, .asciz "xen-3.0")
-#ifdef CONFIG_X86_32
- ELFNOTE(Xen, XEN_ELFNOTE_VIRT_BASE, _ASM_PTR __PAGE_OFFSET)
-#else
ELFNOTE(Xen, XEN_ELFNOTE_VIRT_BASE, _ASM_PTR __START_KERNEL_map)
/* Map the p2m table to a 512GB-aligned user address. */
ELFNOTE(Xen, XEN_ELFNOTE_INIT_P2M, .quad (PUD_SIZE * PTRS_PER_PUD))
-#endif
#ifdef CONFIG_XEN_PV
ELFNOTE(Xen, XEN_ELFNOTE_ENTRY, _ASM_PTR startup_xen)
#endif
diff --git a/arch/x86/xen/xen-ops.h b/arch/x86/xen/xen-ops.h
index 2f111f47ba98..cfe9170e3970 100644
--- a/arch/x86/xen/xen-ops.h
+++ b/arch/x86/xen/xen-ops.h
@@ -12,10 +12,8 @@ extern const char xen_hypervisor_callback[];
extern const char xen_failsafe_callback[];

void xen_sysenter_target(void);
-#ifdef CONFIG_X86_64
void xen_syscall_target(void);
void xen_syscall32_target(void);
-#endif

extern void *xen_initial_gdt;

@@ -34,15 +32,12 @@ void xen_setup_mfn_list_list(void);
void xen_build_mfn_list_list(void);
void xen_setup_machphys_mapping(void);
void xen_setup_kernel_pagetable(pgd_t *pgd, unsigned long max_pfn);
-void xen_reserve_top(void);
void __init xen_reserve_special_pages(void);
void __init xen_pt_check_e820(void);

void xen_mm_pin_all(void);
void xen_mm_unpin_all(void);
-#ifdef CONFIG_X86_64
void __init xen_relocate_p2m(void);
-#endif

bool __init xen_is_e820_reserved(phys_addr_t start, phys_addr_t size);
unsigned long __ref xen_chk_extra_mem(unsigned long pfn);
diff --git a/drivers/xen/Kconfig b/drivers/xen/Kconfig
index ec6558b79e9d..c359a2c04d80 100644
--- a/drivers/xen/Kconfig
+++ b/drivers/xen/Kconfig
@@ -63,9 +63,7 @@ config XEN_BALLOON_MEMORY_HOTPLUG

config XEN_BALLOON_MEMORY_HOTPLUG_LIMIT
int "Hotplugged memory limit (in GiB) for a PV guest"
- default 512 if X86_64
- default 4 if X86_32
- range 0 64 if X86_32
+ default 512
depends on XEN_HAVE_PVMMU
depends on XEN_BALLOON_MEMORY_HOTPLUG
help
--
2.16.4
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