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-rw-r--r--arch/x86/entry/entry_32.S13
-rw-r--r--arch/x86/entry/entry_64_compat.S20
-rw-r--r--arch/x86/include/asm/cpufeature.h1
-rw-r--r--arch/x86/include/asm/paravirt.h12
-rw-r--r--arch/x86/include/asm/paravirt_types.h17
-rw-r--r--arch/x86/kernel/asm-offsets.c3
-rw-r--r--arch/x86/kernel/asm-offsets_64.c1
-rw-r--r--arch/x86/kernel/paravirt.c12
-rw-r--r--arch/x86/kernel/paravirt_patch_32.c2
-rw-r--r--arch/x86/kernel/paravirt_patch_64.c3
-rw-r--r--arch/x86/xen/enlighten.c7
-rw-r--r--arch/x86/xen/xen-asm_32.S14
-rw-r--r--arch/x86/xen/xen-asm_64.S19
-rw-r--r--arch/x86/xen/xen-ops.h3
14 files changed, 17 insertions, 110 deletions
diff --git a/arch/x86/entry/entry_32.S b/arch/x86/entry/entry_32.S
index 3eb572ed3d7a..9870c972d345 100644
--- a/arch/x86/entry/entry_32.S
+++ b/arch/x86/entry/entry_32.S
@@ -308,8 +308,9 @@ sysenter_past_esp:
movl %esp, %eax
call do_fast_syscall_32
- testl %eax, %eax
- jz .Lsyscall_32_done
+ /* XEN PV guests always use IRET path */
+ ALTERNATIVE "testl %eax, %eax; jz .Lsyscall_32_done", \
+ "jmp .Lsyscall_32_done", X86_FEATURE_XENPV
/* Opportunistic SYSEXIT */
TRACE_IRQS_ON /* User mode traces as IRQs on. */
@@ -328,7 +329,8 @@ sysenter_past_esp:
* Return back to the vDSO, which will pop ecx and edx.
* Don't bother with DS and ES (they already contain __USER_DS).
*/
- ENABLE_INTERRUPTS_SYSEXIT
+ sti
+ sysexit
.pushsection .fixup, "ax"
2: movl $0, PT_FS(%esp)
@@ -551,11 +553,6 @@ ENTRY(native_iret)
iret
_ASM_EXTABLE(native_iret, iret_exc)
END(native_iret)
-
-ENTRY(native_irq_enable_sysexit)
- sti
- sysexit
-END(native_irq_enable_sysexit)
#endif
ENTRY(overflow)
diff --git a/arch/x86/entry/entry_64_compat.S b/arch/x86/entry/entry_64_compat.S
index c3201830a85e..bbcb285ac781 100644
--- a/arch/x86/entry/entry_64_compat.S
+++ b/arch/x86/entry/entry_64_compat.S
@@ -18,13 +18,6 @@
.section .entry.text, "ax"
-#ifdef CONFIG_PARAVIRT
-ENTRY(native_usergs_sysret32)
- swapgs
- sysretl
-ENDPROC(native_usergs_sysret32)
-#endif
-
/*
* 32-bit SYSENTER instruction entry.
*
@@ -121,8 +114,9 @@ sysenter_flags_fixed:
movq %rsp, %rdi
call do_fast_syscall_32
- testl %eax, %eax
- jz .Lsyscall_32_done
+ /* XEN PV guests always use IRET path */
+ ALTERNATIVE "testl %eax, %eax; jz .Lsyscall_32_done", \
+ "jmp .Lsyscall_32_done", X86_FEATURE_XENPV
jmp sysret32_from_system_call
sysenter_fix_flags:
@@ -200,8 +194,9 @@ ENTRY(entry_SYSCALL_compat)
movq %rsp, %rdi
call do_fast_syscall_32
- testl %eax, %eax
- jz .Lsyscall_32_done
+ /* XEN PV guests always use IRET path */
+ ALTERNATIVE "testl %eax, %eax; jz .Lsyscall_32_done", \
+ "jmp .Lsyscall_32_done", X86_FEATURE_XENPV
/* Opportunistic SYSRET */
sysret32_from_system_call:
@@ -236,7 +231,8 @@ sysret32_from_system_call:
xorq %r9, %r9
xorq %r10, %r10
movq RSP-ORIG_RAX(%rsp), %rsp
- USERGS_SYSRET32
+ swapgs
+ sysretl
END(entry_SYSCALL_compat)
/*
diff --git a/arch/x86/include/asm/cpufeature.h b/arch/x86/include/asm/cpufeature.h
index e4f8010f22e0..f7ba9fbf12ee 100644
--- a/arch/x86/include/asm/cpufeature.h
+++ b/arch/x86/include/asm/cpufeature.h
@@ -216,6 +216,7 @@
#define X86_FEATURE_PAUSEFILTER ( 8*32+13) /* AMD filtered pause intercept */
#define X86_FEATURE_PFTHRESHOLD ( 8*32+14) /* AMD pause filter threshold */
#define X86_FEATURE_VMMCALL ( 8*32+15) /* Prefer vmmcall to vmcall */
+#define X86_FEATURE_XENPV ( 8*32+16) /* "" Xen paravirtual guest */
/* Intel-defined CPU features, CPUID level 0x00000007:0 (ebx), word 9 */
diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h
index 10d0596433f8..1b71c3aeae86 100644
--- a/arch/x86/include/asm/paravirt.h
+++ b/arch/x86/include/asm/paravirt.h
@@ -922,23 +922,11 @@ extern void default_banner(void);
call PARA_INDIRECT(pv_irq_ops+PV_IRQ_irq_enable); \
PV_RESTORE_REGS(clobbers | CLBR_CALLEE_SAVE);)
-#define USERGS_SYSRET32 \
- PARA_SITE(PARA_PATCH(pv_cpu_ops, PV_CPU_usergs_sysret32), \
- CLBR_NONE, \
- jmp PARA_INDIRECT(pv_cpu_ops+PV_CPU_usergs_sysret32))
-
#ifdef CONFIG_X86_32
#define GET_CR0_INTO_EAX \
push %ecx; push %edx; \
call PARA_INDIRECT(pv_cpu_ops+PV_CPU_read_cr0); \
pop %edx; pop %ecx
-
-#define ENABLE_INTERRUPTS_SYSEXIT \
- PARA_SITE(PARA_PATCH(pv_cpu_ops, PV_CPU_irq_enable_sysexit), \
- CLBR_NONE, \
- jmp PARA_INDIRECT(pv_cpu_ops+PV_CPU_irq_enable_sysexit))
-
-
#else /* !CONFIG_X86_32 */
/*
diff --git a/arch/x86/include/asm/paravirt_types.h b/arch/x86/include/asm/paravirt_types.h
index 31247b5bff7c..702c8bdf7b66 100644
--- a/arch/x86/include/asm/paravirt_types.h
+++ b/arch/x86/include/asm/paravirt_types.h
@@ -157,15 +157,6 @@ struct pv_cpu_ops {
u64 (*read_pmc)(int counter);
-#ifdef CONFIG_X86_32
- /*
- * Atomically enable interrupts and return to userspace. This
- * is only used in 32-bit kernels. 64-bit kernels use
- * usergs_sysret32 instead.
- */
- void (*irq_enable_sysexit)(void);
-#endif
-
/*
* Switch to usermode gs and return to 64-bit usermode using
* sysret. Only used in 64-bit kernels to return to 64-bit
@@ -174,14 +165,6 @@ struct pv_cpu_ops {
*/
void (*usergs_sysret64)(void);
- /*
- * Switch to usermode gs and return to 32-bit usermode using
- * sysret. Used to return to 32-on-64 compat processes.
- * Other usermode register state, including %esp, must already
- * be restored.
- */
- void (*usergs_sysret32)(void);
-
/* Normal iret. Jump to this with the standard iret stack
frame set up. */
void (*iret)(void);
diff --git a/arch/x86/kernel/asm-offsets.c b/arch/x86/kernel/asm-offsets.c
index 439df975bc7a..84a7524b202c 100644
--- a/arch/x86/kernel/asm-offsets.c
+++ b/arch/x86/kernel/asm-offsets.c
@@ -65,9 +65,6 @@ void common(void) {
OFFSET(PV_IRQ_irq_disable, pv_irq_ops, irq_disable);
OFFSET(PV_IRQ_irq_enable, pv_irq_ops, irq_enable);
OFFSET(PV_CPU_iret, pv_cpu_ops, iret);
-#ifdef CONFIG_X86_32
- OFFSET(PV_CPU_irq_enable_sysexit, pv_cpu_ops, irq_enable_sysexit);
-#endif
OFFSET(PV_CPU_read_cr0, pv_cpu_ops, read_cr0);
OFFSET(PV_MMU_read_cr2, pv_mmu_ops, read_cr2);
#endif
diff --git a/arch/x86/kernel/asm-offsets_64.c b/arch/x86/kernel/asm-offsets_64.c
index d8f42f902a0f..f2edafb5f24e 100644
--- a/arch/x86/kernel/asm-offsets_64.c
+++ b/arch/x86/kernel/asm-offsets_64.c
@@ -23,7 +23,6 @@ int main(void)
{
#ifdef CONFIG_PARAVIRT
OFFSET(PV_IRQ_adjust_exception_frame, pv_irq_ops, adjust_exception_frame);
- OFFSET(PV_CPU_usergs_sysret32, pv_cpu_ops, usergs_sysret32);
OFFSET(PV_CPU_usergs_sysret64, pv_cpu_ops, usergs_sysret64);
OFFSET(PV_CPU_swapgs, pv_cpu_ops, swapgs);
BLANK();
diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c
index c2130aef3f9d..8c19b4d5e719 100644
--- a/arch/x86/kernel/paravirt.c
+++ b/arch/x86/kernel/paravirt.c
@@ -162,10 +162,6 @@ unsigned paravirt_patch_default(u8 type, u16 clobbers, void *insnbuf,
ret = paravirt_patch_ident_64(insnbuf, len);
else if (type == PARAVIRT_PATCH(pv_cpu_ops.iret) ||
-#ifdef CONFIG_X86_32
- type == PARAVIRT_PATCH(pv_cpu_ops.irq_enable_sysexit) ||
-#endif
- type == PARAVIRT_PATCH(pv_cpu_ops.usergs_sysret32) ||
type == PARAVIRT_PATCH(pv_cpu_ops.usergs_sysret64))
/* If operation requires a jmp, then jmp */
ret = paravirt_patch_jmp(insnbuf, opfunc, addr, len);
@@ -220,8 +216,6 @@ static u64 native_steal_clock(int cpu)
/* These are in entry.S */
extern void native_iret(void);
-extern void native_irq_enable_sysexit(void);
-extern void native_usergs_sysret32(void);
extern void native_usergs_sysret64(void);
static struct resource reserve_ioports = {
@@ -379,13 +373,7 @@ __visible struct pv_cpu_ops pv_cpu_ops = {
.load_sp0 = native_load_sp0,
-#if defined(CONFIG_X86_32)
- .irq_enable_sysexit = native_irq_enable_sysexit,
-#endif
#ifdef CONFIG_X86_64
-#ifdef CONFIG_IA32_EMULATION
- .usergs_sysret32 = native_usergs_sysret32,
-#endif
.usergs_sysret64 = native_usergs_sysret64,
#endif
.iret = native_iret,
diff --git a/arch/x86/kernel/paravirt_patch_32.c b/arch/x86/kernel/paravirt_patch_32.c
index c89f50a76e97..158dc0650d5d 100644
--- a/arch/x86/kernel/paravirt_patch_32.c
+++ b/arch/x86/kernel/paravirt_patch_32.c
@@ -5,7 +5,6 @@ DEF_NATIVE(pv_irq_ops, irq_enable, "sti");
DEF_NATIVE(pv_irq_ops, restore_fl, "push %eax; popf");
DEF_NATIVE(pv_irq_ops, save_fl, "pushf; pop %eax");
DEF_NATIVE(pv_cpu_ops, iret, "iret");
-DEF_NATIVE(pv_cpu_ops, irq_enable_sysexit, "sti; sysexit");
DEF_NATIVE(pv_mmu_ops, read_cr2, "mov %cr2, %eax");
DEF_NATIVE(pv_mmu_ops, write_cr3, "mov %eax, %cr3");
DEF_NATIVE(pv_mmu_ops, read_cr3, "mov %cr3, %eax");
@@ -46,7 +45,6 @@ unsigned native_patch(u8 type, u16 clobbers, void *ibuf,
PATCH_SITE(pv_irq_ops, restore_fl);
PATCH_SITE(pv_irq_ops, save_fl);
PATCH_SITE(pv_cpu_ops, iret);
- PATCH_SITE(pv_cpu_ops, irq_enable_sysexit);
PATCH_SITE(pv_mmu_ops, read_cr2);
PATCH_SITE(pv_mmu_ops, read_cr3);
PATCH_SITE(pv_mmu_ops, write_cr3);
diff --git a/arch/x86/kernel/paravirt_patch_64.c b/arch/x86/kernel/paravirt_patch_64.c
index 8aa05583bc42..e70087a04cc8 100644
--- a/arch/x86/kernel/paravirt_patch_64.c
+++ b/arch/x86/kernel/paravirt_patch_64.c
@@ -13,9 +13,7 @@ DEF_NATIVE(pv_mmu_ops, flush_tlb_single, "invlpg (%rdi)");
DEF_NATIVE(pv_cpu_ops, clts, "clts");
DEF_NATIVE(pv_cpu_ops, wbinvd, "wbinvd");
-DEF_NATIVE(pv_cpu_ops, irq_enable_sysexit, "swapgs; sti; sysexit");
DEF_NATIVE(pv_cpu_ops, usergs_sysret64, "swapgs; sysretq");
-DEF_NATIVE(pv_cpu_ops, usergs_sysret32, "swapgs; sysretl");
DEF_NATIVE(pv_cpu_ops, swapgs, "swapgs");
DEF_NATIVE(, mov32, "mov %edi, %eax");
@@ -55,7 +53,6 @@ unsigned native_patch(u8 type, u16 clobbers, void *ibuf,
PATCH_SITE(pv_irq_ops, save_fl);
PATCH_SITE(pv_irq_ops, irq_enable);
PATCH_SITE(pv_irq_ops, irq_disable);
- PATCH_SITE(pv_cpu_ops, usergs_sysret32);
PATCH_SITE(pv_cpu_ops, usergs_sysret64);
PATCH_SITE(pv_cpu_ops, swapgs);
PATCH_SITE(pv_mmu_ops, read_cr2);
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index 5774800ff583..a068e36382b7 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -1229,10 +1229,7 @@ static const struct pv_cpu_ops xen_cpu_ops __initconst = {
.iret = xen_iret,
#ifdef CONFIG_X86_64
- .usergs_sysret32 = xen_sysret32,
.usergs_sysret64 = xen_sysret64,
-#else
- .irq_enable_sysexit = xen_sysexit,
#endif
.load_tr_desc = paravirt_nop,
@@ -1886,8 +1883,10 @@ EXPORT_SYMBOL_GPL(xen_hvm_need_lapic);
static void xen_set_cpu_features(struct cpuinfo_x86 *c)
{
- if (xen_pv_domain())
+ if (xen_pv_domain()) {
clear_cpu_bug(c, X86_BUG_SYSRET_SS_ATTRS);
+ set_cpu_cap(c, X86_FEATURE_XENPV);
+ }
}
const struct hypervisor_x86 x86_hyper_xen = {
diff --git a/arch/x86/xen/xen-asm_32.S b/arch/x86/xen/xen-asm_32.S
index fd92a64d748e..feb6d40a0860 100644
--- a/arch/x86/xen/xen-asm_32.S
+++ b/arch/x86/xen/xen-asm_32.S
@@ -35,20 +35,6 @@ check_events:
ret
/*
- * We can't use sysexit directly, because we're not running in ring0.
- * But we can easily fake it up using iret. Assuming xen_sysexit is
- * jumped to with a standard stack frame, we can just strip it back to
- * a standard iret frame and use iret.
- */
-ENTRY(xen_sysexit)
- movl PT_EAX(%esp), %eax /* Shouldn't be necessary? */
- orl $X86_EFLAGS_IF, PT_EFLAGS(%esp)
- lea PT_EIP(%esp), %esp
-
- jmp xen_iret
-ENDPROC(xen_sysexit)
-
-/*
* This is run where a normal iret would be run, with the same stack setup:
* 8: eflags
* 4: cs
diff --git a/arch/x86/xen/xen-asm_64.S b/arch/x86/xen/xen-asm_64.S
index f22667abf7b9..cc8acc410ddb 100644
--- a/arch/x86/xen/xen-asm_64.S
+++ b/arch/x86/xen/xen-asm_64.S
@@ -68,25 +68,6 @@ ENTRY(xen_sysret64)
ENDPATCH(xen_sysret64)
RELOC(xen_sysret64, 1b+1)
-ENTRY(xen_sysret32)
- /*
- * We're already on the usermode stack at this point, but
- * still with the kernel gs, so we can easily switch back
- */
- movq %rsp, PER_CPU_VAR(rsp_scratch)
- movq PER_CPU_VAR(cpu_current_top_of_stack), %rsp
-
- pushq $__USER32_DS
- pushq PER_CPU_VAR(rsp_scratch)
- pushq %r11
- pushq $__USER32_CS
- pushq %rcx
-
- pushq $0
-1: jmp hypercall_iret
-ENDPATCH(xen_sysret32)
-RELOC(xen_sysret32, 1b+1)
-
/*
* Xen handles syscall callbacks much like ordinary exceptions, which
* means we have:
diff --git a/arch/x86/xen/xen-ops.h b/arch/x86/xen/xen-ops.h
index 1399423f3418..4140b070f2e9 100644
--- a/arch/x86/xen/xen-ops.h
+++ b/arch/x86/xen/xen-ops.h
@@ -139,9 +139,6 @@ DECL_ASM(void, xen_restore_fl_direct, unsigned long);
/* These are not functions, and cannot be called normally */
__visible void xen_iret(void);
-#ifdef CONFIG_X86_32
-__visible void xen_sysexit(void);
-#endif
__visible void xen_sysret32(void);
__visible void xen_sysret64(void);
__visible void xen_adjust_exception_frame(void);