|
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [Xen-devel] [PATCH v3 2/3] x86/irqs: Move interrupt-stub generation out of C
In addition, generate stubs for reserved exceptions. These go through the
standard handle_exception mechanism, although the C handler do_reserved_trap()
is a terminal error path.
* Move all automatic stub generation out of i8259.c and into entry.S.
* Move patching of the master IDT into trap_init(). Provide ASSERT()s to
ensure we have fully populated the IDT and don't accidentally clobbered any
preexisting traps.
* Demote TRAP_copro_seg and TRAP_spurious_int to being reserved exceptions
and remove their custom entry points.
* Point double_fault's exception_table entry at do_reserved_trap. We do not
ever expect to enter a real double fault this way.
* Acquaint Xen with #VE but leave it reserved.
Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
CC: Keir Fraser <keir@xxxxxxx>
CC: Jan Beulich <JBeulich@xxxxxxxx>
CC: Tim Deegan <tim@xxxxxxx>
CC: Feng Wu <feng.wu@xxxxxxxxx>
---
v3:
* Reuse exiting handle_exception infrastructure.
* Autogenerate in entry.S rather than adding the new file irqgen.S
* Test whether the processor pushed an error code or not for the
automatically generated stubs. This was tested using "int $0x1f" and
observing a properly aligned register dump.
v2:
* Far less .macro hackary, inspired by Feng's patch of a similar nature. On
consideration, having literal symbol names is very little use, either in
the disassembly, or running hypervisor. In hindsight this is new version is
substantially more likely to compile under clang, although I don't have a
compiler to hand.
---
xen/arch/x86/i8259.c | 69 +--------------------------------------
xen/arch/x86/traps.c | 36 +++++++++++++++-----
xen/arch/x86/x86_64/entry.S | 67 +++++++++++++++++++++++++++++--------
xen/include/asm-x86/asm_defns.h | 5 ---
xen/include/asm-x86/processor.h | 4 +--
5 files changed, 85 insertions(+), 96 deletions(-)
diff --git a/xen/arch/x86/i8259.c b/xen/arch/x86/i8259.c
index 9fec490..9f99995 100644
--- a/xen/arch/x86/i8259.c
+++ b/xen/arch/x86/i8259.c
@@ -23,65 +23,6 @@
#include <io_ports.h>
/*
- * Common place to define all x86 IRQ vectors
- *
- * This builds up the IRQ handler stubs using some ugly macros in irq.h
- *
- * These macros create the low-level assembly IRQ routines that save
- * register context and call do_IRQ(). do_IRQ() then does all the
- * operations that are needed to keep the AT (or SMP IOAPIC)
- * interrupt-controller happy.
- */
-
-__asm__(".section .text");
-
-#define IRQ_NAME(nr) VEC##nr##_interrupt
-
-#define BI(nr) \
-void IRQ_NAME(nr)(void); \
-__asm__( \
-".if " STR(0x##nr) " >= " STR(FIRST_DYNAMIC_VECTOR) "\n" \
-__ALIGN_STR "\n" \
-STR(IRQ_NAME(nr)) ":\n\t" \
-BUILD_IRQ(0x##nr) "\n" \
-".else\n" \
-".equ " STR(IRQ_NAME(nr)) ", 0\n" \
-".endif\n")
-
-#define BUILD_16_IRQS(x) \
- BI(x##0); BI(x##1); BI(x##2); BI(x##3); \
- BI(x##4); BI(x##5); BI(x##6); BI(x##7); \
- BI(x##8); BI(x##9); BI(x##a); BI(x##b); \
- BI(x##c); BI(x##d); BI(x##e); BI(x##f)
-
-BUILD_16_IRQS(0); BUILD_16_IRQS(1); BUILD_16_IRQS(2); BUILD_16_IRQS(3);
-BUILD_16_IRQS(4); BUILD_16_IRQS(5); BUILD_16_IRQS(6); BUILD_16_IRQS(7);
-BUILD_16_IRQS(8); BUILD_16_IRQS(9); BUILD_16_IRQS(a); BUILD_16_IRQS(b);
-BUILD_16_IRQS(c); BUILD_16_IRQS(d); BUILD_16_IRQS(e); BUILD_16_IRQS(f);
-
-#undef BUILD_16_IRQS
-#undef BI
-
-
-#define IRQ(x,y) IRQ_NAME(x##y)
-
-#define IRQLIST_16(x) \
- IRQ(x,0), IRQ(x,1), IRQ(x,2), IRQ(x,3), \
- IRQ(x,4), IRQ(x,5), IRQ(x,6), IRQ(x,7), \
- IRQ(x,8), IRQ(x,9), IRQ(x,a), IRQ(x,b), \
- IRQ(x,c), IRQ(x,d), IRQ(x,e), IRQ(x,f)
-
-static void (*__initdata interrupt[NR_VECTORS])(void) = {
- IRQLIST_16(0), IRQLIST_16(1), IRQLIST_16(2), IRQLIST_16(3),
- IRQLIST_16(4), IRQLIST_16(5), IRQLIST_16(6), IRQLIST_16(7),
- IRQLIST_16(8), IRQLIST_16(9), IRQLIST_16(a), IRQLIST_16(b),
- IRQLIST_16(c), IRQLIST_16(d), IRQLIST_16(e), IRQLIST_16(f)
-};
-
-#undef IRQ
-#undef IRQLIST_16
-
-/*
* This is the 'legacy' 8259A Programmable Interrupt Controller,
* present in the majority of PC/AT boxes.
* plus some generic x86 specific things if generic specifics makes
@@ -395,7 +336,7 @@ static struct irqaction __read_mostly cascade = {
no_action, "cascade", NULL};
void __init init_IRQ(void)
{
- int vector, irq, cpu = smp_processor_id();
+ int irq, cpu = smp_processor_id();
init_bsp_APIC();
@@ -403,14 +344,6 @@ void __init init_IRQ(void)
BUG_ON(init_irq_data() < 0);
- for ( vector = FIRST_DYNAMIC_VECTOR; vector < NR_VECTORS; vector++ )
- {
- if (vector == HYPERCALL_VECTOR || vector == LEGACY_SYSCALL_VECTOR)
- continue;
- BUG_ON(!interrupt[vector]);
- set_intr_gate(vector, interrupt[vector]);
- }
-
for (irq = 0; platform_legacy_irq(irq); irq++) {
struct irq_desc *desc = irq_to_desc(irq);
diff --git a/xen/arch/x86/traps.c b/xen/arch/x86/traps.c
index 136821f..8863334 100644
--- a/xen/arch/x86/traps.c
+++ b/xen/arch/x86/traps.c
@@ -383,7 +383,7 @@ static const char *trapstr(unsigned int trapnr)
"coprocessor segment", "invalid tss", "segment not found",
"stack error", "general protection fault", "page fault",
"spurious interrupt", "coprocessor error", "alignment check",
- "machine check", "simd error"
+ "machine check", "simd error", "virtualisation exception"
};
return trapnr < ARRAY_SIZE(strings) ? strings[trapnr] : "???";
@@ -534,6 +534,15 @@ int set_guest_nmi_trapbounce(void)
return !null_trap_bounce(v, tb);
}
+void do_reserved_trap(struct cpu_user_regs *regs)
+{
+ unsigned int trapnr = regs->entry_vector;
+
+ DEBUGGER_trap_fatal(trapnr, regs);
+ show_execution_state(regs);
+ panic("FATAL RESERVED TRAP %#x: %s", trapnr, trapstr(trapnr));
+}
+
static void do_trap(struct cpu_user_regs *regs, int use_error_code)
{
struct vcpu *curr = current;
@@ -589,7 +598,6 @@ void do_##name(struct cpu_user_regs *regs) \
DO_ERROR_NOCODE(divide_error)
DO_ERROR_NOCODE(overflow)
DO_ERROR_NOCODE(bounds)
-DO_ERROR_NOCODE(coprocessor_segment_overrun)
DO_ERROR( invalid_TSS)
DO_ERROR( segment_not_present)
DO_ERROR( stack_segment)
@@ -3414,10 +3422,6 @@ void do_debug(struct cpu_user_regs *regs)
return;
}
-void do_spurious_interrupt_bug(struct cpu_user_regs *regs)
-{
-}
-
static void __set_intr_gate(unsigned int n, uint32_t dpl, void *addr)
{
int i;
@@ -3516,13 +3520,11 @@ void __init init_idt_traps(void)
set_intr_gate(TRAP_invalid_op,&invalid_op);
set_intr_gate(TRAP_no_device,&device_not_available);
set_intr_gate(TRAP_double_fault,&double_fault);
- set_intr_gate(TRAP_copro_seg,&coprocessor_segment_overrun);
set_intr_gate(TRAP_invalid_tss,&invalid_TSS);
set_intr_gate(TRAP_no_segment,&segment_not_present);
set_intr_gate(TRAP_stack_error,&stack_segment);
set_intr_gate(TRAP_gp_fault,&general_protection);
set_intr_gate(TRAP_page_fault,&early_page_fault);
- set_intr_gate(TRAP_spurious_int,&spurious_interrupt_bug);
set_intr_gate(TRAP_copro_error,&coprocessor_error);
set_intr_gate(TRAP_alignment_check,&alignment_check);
set_intr_gate(TRAP_machine_check,&machine_check);
@@ -3540,8 +3542,11 @@ void __init init_idt_traps(void)
this_cpu(compat_gdt_table) = boot_cpu_compat_gdt_table;
}
+extern void (*__initconst autogen_entrypoints[NR_VECTORS])(void);
void __init trap_init(void)
{
+ unsigned int vector;
+
/* Replace early pagefault with real pagefault handler. */
set_intr_gate(TRAP_page_fault, &page_fault);
@@ -3552,6 +3557,21 @@ void __init trap_init(void)
/* Fast trap for int80 (faster than taking the #GP-fixup path). */
_set_gate(idt_table + 0x80, SYS_DESC_trap_gate, 3, &int80_direct_trap);
+ for ( vector = 0; vector < NR_VECTORS; ++vector )
+ {
+ if ( autogen_entrypoints[vector] )
+ {
+ /* Found autogen entry: check we won't clobber an existing trap. */
+ ASSERT(idt_table[vector].b == 0);
+ set_intr_gate(vector, autogen_entrypoints[vector]);
+ }
+ else
+ {
+ /* No entry point: confirm we have an existing trap in place. */
+ ASSERT(idt_table[vector].b != 0);
+ }
+ }
+
percpu_traps_init();
cpu_init();
diff --git a/xen/arch/x86/x86_64/entry.S b/xen/arch/x86/x86_64/entry.S
index 4796e65..5d693fc 100644
--- a/xen/arch/x86/x86_64/entry.S
+++ b/xen/arch/x86/x86_64/entry.S
@@ -586,11 +586,6 @@ ENTRY(invalid_op)
movl $TRAP_invalid_op,4(%rsp)
jmp handle_exception
-ENTRY(coprocessor_segment_overrun)
- pushq $0
- movl $TRAP_copro_seg,4(%rsp)
- jmp handle_exception
-
ENTRY(invalid_TSS)
movl $TRAP_invalid_tss,4(%rsp)
jmp handle_exception
@@ -611,11 +606,6 @@ ENTRY(alignment_check)
movl $TRAP_alignment_check,4(%rsp)
jmp handle_exception
-ENTRY(spurious_interrupt_bug)
- pushq $0
- movl $TRAP_spurious_int,4(%rsp)
- jmp handle_exception
-
ENTRY(double_fault)
movl $TRAP_double_fault,4(%rsp)
/* Set AC to reduce chance of further SMAP faults */
@@ -716,18 +706,21 @@ ENTRY(exception_table)
.quad do_bounds
.quad do_invalid_op
.quad do_device_not_available
- .quad 0 # double_fault
- .quad do_coprocessor_segment_overrun
+ .quad do_reserved_trap /* double_fault - has its own entry. */
+ .quad do_reserved_trap /* coproc_seg_overrun - Intel 387 only. */
.quad do_invalid_TSS
.quad do_segment_not_present
.quad do_stack_segment
.quad do_general_protection
.quad do_page_fault
- .quad do_spurious_interrupt_bug
+ .quad do_reserved_trap /* Default PIC spurious irq - architecturally
reserved. */
.quad do_coprocessor_error
.quad do_alignment_check
.quad do_machine_check
.quad do_simd_coprocessor_error
+ .rept TRAP_last_reserved + 1 - ((. - exception_table) / 8)
+ .quad do_reserved_trap /* Architecturally reserved exceptions. */
+ .endr
ENTRY(hypercall_table)
.quad do_set_trap_table /* 0 */
@@ -824,3 +817,51 @@ ENTRY(hypercall_args_table)
.rept NR_hypercalls-(.-hypercall_args_table)
.byte 0 /* do_ni_hypercall */
.endr
+
+/* Table of automatically generated entry points. One per vector. */
+.section ".init.rodata", "a"
+GLOBAL(autogen_entrypoints)
+ /* pop into the .init.rodata section and record an entry point. */
+ .macro entrypoint ent
+ .pushsection ".init.rodata", "a"
+ .quad \ent
+ .popsection
+ .endm
+
+.text
+autogen_stubs: /* Automatically generated stubs. */
+
+ vec = 0
+ .rept NR_VECTORS
+ ALIGN
+
+ /* Common interrupts, heading towards do_IRQ(). */
+ .if vec >= FIRST_DYNAMIC_VECTOR && vec != HYPERCALL_VECTOR && vec !=
LEGACY_SYSCALL_VECTOR
+
+1: pushq $0
+ movb $vec,4(%rsp)
+ jmp common_interrupt
+
+ entrypoint 1b
+
+ /* Reserved exceptions, heading towards do_reserved_trap(). */
+ .elseif vec == TRAP_copro_seg || vec == TRAP_spurious_int || (vec >
TRAP_simd_error && vec <= TRAP_last_reserved)
+
+1: test $0x8,%sp /* 64bit exception frames are 16 byte aligned,
but the word */
+ jz 2f /* size is 8 bytes. Check whether the processor
gave us an */
+ pushq $0 /* error code, and insert an empty one if not.
*/
+2: movb $vec,4(%rsp)
+ jmp handle_exception
+
+ entrypoint 1b
+
+ /* Hand crafted entry points above. */
+ .else
+ entrypoint 0
+ .endif
+
+ vec = vec + 1
+ .endr
+
+ .section ".init.rodata", "a"
+ .size autogen_entrypoints, . - autogen_entrypoints
diff --git a/xen/include/asm-x86/asm_defns.h b/xen/include/asm-x86/asm_defns.h
index df4873b..87a462f 100644
--- a/xen/include/asm-x86/asm_defns.h
+++ b/xen/include/asm-x86/asm_defns.h
@@ -357,9 +357,4 @@ static inline void stac(void)
#define REX64_PREFIX "rex64/"
#endif
-#define BUILD_IRQ(nr) \
- "pushq $0\n\t" \
- "movl $"#nr",4(%rsp)\n\t" \
- "jmp common_interrupt"
-
#endif /* __X86_ASM_DEFNS_H__ */
diff --git a/xen/include/asm-x86/processor.h b/xen/include/asm-x86/processor.h
index 805ec34..4a60eb0 100644
--- a/xen/include/asm-x86/processor.h
+++ b/xen/include/asm-x86/processor.h
@@ -113,6 +113,7 @@
#define TRAP_alignment_check 17
#define TRAP_machine_check 18
#define TRAP_simd_error 19
+#define TRAP_virtualisation 20
#define TRAP_last_reserved 31
/* Set for entry via SYSCALL. Informs return code to use SYSRETQ not IRETQ. */
@@ -503,7 +504,6 @@ DECLARE_TRAP_HANDLER(bounds);
DECLARE_TRAP_HANDLER(invalid_op);
DECLARE_TRAP_HANDLER(device_not_available);
DECLARE_TRAP_HANDLER(double_fault);
-DECLARE_TRAP_HANDLER(coprocessor_segment_overrun);
DECLARE_TRAP_HANDLER(invalid_TSS);
DECLARE_TRAP_HANDLER(segment_not_present);
DECLARE_TRAP_HANDLER(stack_segment);
@@ -514,12 +514,12 @@ DECLARE_TRAP_HANDLER(coprocessor_error);
DECLARE_TRAP_HANDLER(simd_coprocessor_error);
DECLARE_TRAP_HANDLER(machine_check);
DECLARE_TRAP_HANDLER(alignment_check);
-DECLARE_TRAP_HANDLER(spurious_interrupt_bug);
#undef DECLARE_TRAP_HANDLER
void trap_nop(void);
void enable_nmis(void);
void noreturn do_nmi_crash(struct cpu_user_regs *regs);
+void do_reserved_trap(struct cpu_user_regs *regs);
void syscall_enter(void);
void sysenter_entry(void);
--
1.7.10.4
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel
|
 |
Lists.xenproject.org is hosted with RackSpace, monitoring our |