lkml.org 
[lkml]   [2019]   [Jul]   [4]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[RFC][PATCH v2 7/7] x86/entry/64: Pull bits into C
TODO: 32bit, Xen

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
---
arch/x86/entry/entry_64.S | 13 +++-------
arch/x86/include/asm/idtentry.h | 49 ++++++++++++++++++++++++++++++++++++++++
arch/x86/include/asm/traps.h | 1
arch/x86/kernel/cpu/mce/core.c | 2 -
arch/x86/kernel/kvm.c | 4 ---
arch/x86/kernel/traps.c | 30 ++++++++----------------
arch/x86/mm/fault.c | 4 ---
7 files changed, 68 insertions(+), 35 deletions(-)

--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -841,15 +841,6 @@ apicinterrupt IRQ_WORK_VECTOR irq_work
GET_CR2_INTO(%rdx); /* can clobber %rax */
.endif

- TRACE_IRQS_OFF
-
- .if \paranoid == 0
- testb $3, CS(%rsp)
- jz .Lfrom_kernel_no_context_tracking_\@
- CALL_enter_from_user_mode
-.Lfrom_kernel_no_context_tracking_\@:
- .endif
-
movq %rsp, %rdi /* pt_regs pointer */

.if \has_error_code
@@ -863,7 +854,11 @@ apicinterrupt IRQ_WORK_VECTOR irq_work
subq $\ist_offset, CPU_TSS_IST(\shift_ist)
.endif

+ .if \paranoid
+ call \do_sym\()_paranoid
+ .else
call \do_sym
+ .endif

.if \shift_ist != -1
addq $\ist_offset, CPU_TSS_IST(\shift_ist)
--- /dev/null
+++ b/arch/x86/include/asm/idtentry.h
@@ -0,0 +1,49 @@
+#ifndef __ASM_IDTENTRY_H
+#define __ASM_IDTENTRY_H
+
+/* shamelessly stolen from linux/syscalls.h; XXX share */
+
+#define __IDT_MAP0(m,...)
+#define __IDT_MAP1(m,t,a,...) m(t,a)
+#define __IDT_MAP2(m,t,a,...) m(t,a), __IDT_MAP1(m,__VA_ARGS__)
+#define __IDT_MAP3(m,t,a,...) m(t,a), __IDT_MAP2(m,__VA_ARGS__)
+
+#define __IDT_MAP(n,...) __IDT_MAP##n(__VA_ARGS__)
+
+#define __IDT_DECL(t, a) t a
+#define __IDT_ARGS(t, a) a
+#define __IDT_TEST(t, a) (void)BUILD_BUG_ON_ZERO(sizeof(t) != sizeof(long))
+
+#ifdef CONFIG_CONTEXT_TRACKING
+#define CALL_enter_from_user_mode(_regs) \
+ if (static_branch_unlikely(&context_tracking_enabled) && user_mode(_regs)) \
+ enter_from_user_mode()
+#else
+#define CALL_enter_from_user_mode(_regs)
+#endif
+
+#define IDTENTRYx(n, name, ...) \
+ static notrace void __idt_##name(__IDT_MAP(n, __IDT_DECL, __VA_ARGS__)); \
+ NOKPROBE_SYMBOL(__idt_##name); \
+ dotraplinkage notrace void name(__IDT_MAP(n, __IDT_DECL, __VA_ARGS__)) \
+ { \
+ __IDT_MAP(n, __IDT_TEST, __VA_ARGS__); \
+ trace_hardirqs_off(); \
+ CALL_enter_from_user_mode(regs); \
+ __idt_##name(__IDT_MAP(n, __IDT_ARGS, __VA_ARGS__)); \
+ } \
+ NOKPROBE_SYMBOL(name); \
+ dotraplinkage notrace void name##_paranoid(__IDT_MAP(n, __IDT_DECL, __VA_ARGS__)) \
+ { \
+ __IDT_MAP(n, __IDT_TEST, __VA_ARGS__); \
+ trace_hardirqs_off(); \
+ __idt_##name(__IDT_MAP(n, __IDT_ARGS, __VA_ARGS__)); \
+ } \
+ NOKPROBE_SYMBOL(name##_paranoid); \
+ static notrace void __idt_##name(__IDT_MAP(n, __IDT_DECL, __VA_ARGS__))
+
+#define IDTENTRY1(name,...) IDTENTRYx(1, name, __VA_ARGS__)
+#define IDTENTRY2(name,...) IDTENTRYx(2, name, __VA_ARGS__)
+#define IDTENTRY3(name,...) IDTENTRYx(3, name, __VA_ARGS__)
+
+#endif /* __ASM_IDTENTRY_H */
--- a/arch/x86/include/asm/traps.h
+++ b/arch/x86/include/asm/traps.h
@@ -7,6 +7,7 @@

#include <asm/debugreg.h>
#include <asm/siginfo.h> /* TRAP_TRACE, ... */
+#include <asm/idtentry.h>

#define dotraplinkage __visible

--- a/arch/x86/kernel/cpu/mce/core.c
+++ b/arch/x86/kernel/cpu/mce/core.c
@@ -1842,7 +1842,7 @@ static void unexpected_machine_check(str
void (*machine_check_vector)(struct pt_regs *, long error_code) =
unexpected_machine_check;

-dotraplinkage void do_mce(struct pt_regs *regs, long error_code)
+IDTENTRY2(do_mce, struct pt_regs *, regs, long, error_code)
{
machine_check_vector(regs, error_code);
}
--- a/arch/x86/kernel/kvm.c
+++ b/arch/x86/kernel/kvm.c
@@ -241,8 +241,7 @@ u32 kvm_read_and_reset_pf_reason(void)
EXPORT_SYMBOL_GPL(kvm_read_and_reset_pf_reason);
NOKPROBE_SYMBOL(kvm_read_and_reset_pf_reason);

-dotraplinkage void
-do_async_page_fault(struct pt_regs *regs, unsigned long error_code, unsigned long address)
+IDTENTRY3(do_async_page_fault, struct pt_regs *, regs, unsigned long, error_code, unsigned long, address)
{
enum ctx_state prev_state;

@@ -263,7 +262,6 @@ do_async_page_fault(struct pt_regs *regs
break;
}
}
-NOKPROBE_SYMBOL(do_async_page_fault);

static void __init paravirt_ops_setup(void)
{
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -281,7 +281,7 @@ static void do_error_trap(struct pt_regs

#define IP ((void __user *)uprobe_get_trap_addr(regs))
#define DO_ERROR(trapnr, signr, sicode, addr, str, name) \
-dotraplinkage void do_##name(struct pt_regs *regs, long error_code) \
+IDTENTRY2(do_##name, struct pt_regs *, regs, long, error_code) \
{ \
do_error_trap(regs, error_code, str, trapnr, signr, sicode, addr); \
}
@@ -313,7 +313,7 @@ __visible void __noreturn handle_stack_o

#ifdef CONFIG_X86_64
/* Runs on IST stack */
-dotraplinkage void do_double_fault(struct pt_regs *regs, long error_code, unsigned long cr2)
+IDTENTRY3(do_double_fault, struct pt_regs *, regs, long, error_code, unsigned long, cr2)
{
static const char str[] = "double fault";
struct task_struct *tsk = current;
@@ -428,7 +428,7 @@ dotraplinkage void do_double_fault(struc
}
#endif

-dotraplinkage void do_bounds(struct pt_regs *regs, long error_code)
+IDTENTRY2(do_bounds, struct pt_regs *, regs, long, error_code)
{
const struct mpx_bndcsr *bndcsr;

@@ -514,8 +514,7 @@ dotraplinkage void do_bounds(struct pt_r
do_trap(X86_TRAP_BR, SIGSEGV, "bounds", regs, error_code, 0, NULL);
}

-dotraplinkage void
-do_general_protection(struct pt_regs *regs, long error_code)
+IDTENTRY2(do_general_protection, struct pt_regs *, regs, long, error_code)
{
const char *desc = "general protection fault";
struct task_struct *tsk;
@@ -564,9 +563,8 @@ do_general_protection(struct pt_regs *re

force_sig(SIGSEGV, tsk);
}
-NOKPROBE_SYMBOL(do_general_protection);

-dotraplinkage void notrace do_int3(struct pt_regs *regs, long error_code)
+IDTENTRY2(do_int3, struct pt_regs *, regs, long, error_code)
{
#ifdef CONFIG_DYNAMIC_FTRACE
/*
@@ -611,7 +609,6 @@ dotraplinkage void notrace do_int3(struc
exit:
ist_exit(regs);
}
-NOKPROBE_SYMBOL(do_int3);

#ifdef CONFIG_X86_64
/*
@@ -706,7 +703,7 @@ static bool is_sysenter_singlestep(struc
*
* May run on IST stack.
*/
-dotraplinkage void do_debug(struct pt_regs *regs, long error_code)
+IDTENTRY2(do_debug, struct pt_regs *, regs, long, error_code)
{
struct task_struct *tsk = current;
int user_icebp = 0;
@@ -808,7 +805,6 @@ dotraplinkage void do_debug(struct pt_re
exit:
ist_exit(regs);
}
-NOKPROBE_SYMBOL(do_debug);

/*
* Note that we play around with the 'TS' bit in an attempt to get
@@ -855,27 +851,24 @@ static void math_error(struct pt_regs *r
(void __user *)uprobe_get_trap_addr(regs), task);
}

-dotraplinkage void do_coprocessor_error(struct pt_regs *regs, long error_code)
+IDTENTRY2(do_coprocessor_error, struct pt_regs *, regs, long, error_code)
{
RCU_LOCKDEP_WARN(!rcu_is_watching(), "entry code didn't wake RCU");
math_error(regs, error_code, X86_TRAP_MF);
}

-dotraplinkage void
-do_simd_coprocessor_error(struct pt_regs *regs, long error_code)
+IDTENTRY2(do_simd_coprocessor_error, struct pt_regs *, regs, long, error_code)
{
RCU_LOCKDEP_WARN(!rcu_is_watching(), "entry code didn't wake RCU");
math_error(regs, error_code, X86_TRAP_XF);
}

-dotraplinkage void
-do_spurious_interrupt_bug(struct pt_regs *regs, long error_code)
+IDTENTRY2(do_spurious_interrupt_bug, struct pt_regs *, regs, long, error_code)
{
cond_local_irq_enable(regs);
}

-dotraplinkage void
-do_device_not_available(struct pt_regs *regs, long error_code)
+IDTENTRY2(do_device_not_available, struct pt_regs *, regs, long, error_code)
{
unsigned long cr0 = read_cr0();

@@ -906,10 +899,9 @@ do_device_not_available(struct pt_regs *
die("unexpected #NM exception", regs, error_code);
}
}
-NOKPROBE_SYMBOL(do_device_not_available);

#ifdef CONFIG_X86_32
-dotraplinkage void do_iret_error(struct pt_regs *regs, long error_code)
+IDTENTRY2(do_iret_error, struct pt_regs *, regs, long, error_code)
{
RCU_LOCKDEP_WARN(!rcu_is_watching(), "entry code didn't wake RCU");
local_irq_enable();
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -1542,8 +1542,7 @@ trace_page_fault_entries(struct pt_regs
trace_page_fault_kernel(address, regs, error_code);
}

-dotraplinkage void
-do_page_fault(struct pt_regs *regs, unsigned long error_code, unsigned long address)
+IDTENTRY3(do_page_fault, struct pt_regs *, regs, unsigned long, error_code, unsigned long, address)
{
enum ctx_state prev_state;

@@ -1552,4 +1551,3 @@ do_page_fault(struct pt_regs *regs, unsi
__do_page_fault(regs, error_code, address);
exception_exit(prev_state);
}
-NOKPROBE_SYMBOL(do_page_fault);

\
 
 \ /
  Last update: 2019-07-04 22:04    [W:0.179 / U:2.496 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site