diff options
| author | Ingo Molnar <mingo@elte.hu> | 2008-07-14 16:11:52 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2008-07-14 16:11:52 +0200 |
| commit | 5806b81ac1c0c52665b91723fd4146a4f86e386b (patch) | |
| tree | 24ea8763bf308ce1407c1de91dc8de4d2655e1c1 /arch | |
| parent | d14c8a680ccfdeb5e7b9be4d61162c2b373bd1e8 (diff) | |
| parent | 6712e299b7dc78aa4971b85e803435ee6d49a9dd (diff) | |
Merge branch 'auto-ftrace-next' into tracing/for-linus
Conflicts:
arch/x86/kernel/entry_32.S
arch/x86/kernel/process_32.c
arch/x86/kernel/process_64.c
arch/x86/lib/Makefile
include/asm-x86/irqflags.h
kernel/Makefile
kernel/sched.c
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch')
53 files changed, 2862 insertions, 44 deletions
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index b786e68914d..3845e5c8a34 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -14,6 +14,8 @@ config ARM select HAVE_OPROFILE select HAVE_KPROBES if (!XIP_KERNEL) select HAVE_KRETPROBES if (HAVE_KPROBES) + select HAVE_FTRACE if (!XIP_KERNEL) + select HAVE_DYNAMIC_FTRACE if (HAVE_FTRACE) help The ARM series is a line of low-power-consumption RISC chip designs licensed by ARM Ltd and targeted at embedded applications and diff --git a/arch/arm/boot/compressed/Makefile b/arch/arm/boot/compressed/Makefile index de9d9ee5095..95baac4939e 100644 --- a/arch/arm/boot/compressed/Makefile +++ b/arch/arm/boot/compressed/Makefile @@ -69,6 +69,12 @@ SEDFLAGS = s/TEXT_START/$(ZTEXTADDR)/;s/BSS_START/$(ZBSSADDR)/ targets := vmlinux vmlinux.lds piggy.gz piggy.o font.o font.c \ head.o misc.o $(OBJS) + +ifeq ($(CONFIG_FTRACE),y) +ORIG_CFLAGS := $(KBUILD_CFLAGS) +KBUILD_CFLAGS = $(subst -pg, , $(ORIG_CFLAGS)) +endif + EXTRA_CFLAGS := -fpic -fno-builtin EXTRA_AFLAGS := diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile index ad455ff5aeb..eb9092ca800 100644 --- a/arch/arm/kernel/Makefile +++ b/arch/arm/kernel/Makefile @@ -4,6 +4,10 @@ AFLAGS_head.o := -DTEXT_OFFSET=$(TEXT_OFFSET) +ifdef CONFIG_DYNAMIC_FTRACE +CFLAGS_REMOVE_ftrace.o = -pg +endif + # Object file lists. obj-y := compat.o entry-armv.o entry-common.o irq.o \ @@ -18,6 +22,7 @@ obj-$(CONFIG_ARTHUR) += arthur.o obj-$(CONFIG_ISA_DMA) += dma-isa.o obj-$(CONFIG_PCI) += bios32.o isa.o obj-$(CONFIG_SMP) += smp.o +obj-$(CONFIG_DYNAMIC_FTRACE) += ftrace.o obj-$(CONFIG_KEXEC) += machine_kexec.o relocate_kernel.o obj-$(CONFIG_KPROBES) += kprobes.o kprobes-decode.o obj-$(CONFIG_ATAGS_PROC) += atags.o diff --git a/arch/arm/kernel/armksyms.c b/arch/arm/kernel/armksyms.c index 688b7b1ee41..cc7b246e965 100644 --- a/arch/arm/kernel/armksyms.c +++ b/arch/arm/kernel/armksyms.c @@ -18,6 +18,7 @@ #include <asm/io.h> #include <asm/system.h> #include <asm/uaccess.h> +#include <asm/ftrace.h> /* * libgcc functions - functions that are used internally by the @@ -181,3 +182,7 @@ EXPORT_SYMBOL(_find_next_bit_be); #endif EXPORT_SYMBOL(copy_page); + +#ifdef CONFIG_FTRACE +EXPORT_SYMBOL(mcount); +#endif diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S index 597ed00a08d..84694e88b42 100644 --- a/arch/arm/kernel/entry-common.S +++ b/arch/arm/kernel/entry-common.S @@ -9,6 +9,7 @@ */ #include <asm/unistd.h> +#include <asm/ftrace.h> #include <asm/arch/entry-macro.S> #include "entry-header.S" @@ -99,6 +100,56 @@ ENTRY(ret_from_fork) #undef CALL #define CALL(x) .long x +#ifdef CONFIG_FTRACE +#ifdef CONFIG_DYNAMIC_FTRACE +ENTRY(mcount) + stmdb sp!, {r0-r3, lr} + mov r0, lr + sub r0, r0, #MCOUNT_INSN_SIZE + + .globl mcount_call +mcount_call: + bl ftrace_stub + ldmia sp!, {r0-r3, pc} + +ENTRY(ftrace_caller) + stmdb sp!, {r0-r3, lr} + ldr r1, [fp, #-4] + mov r0, lr + sub r0, r0, #MCOUNT_INSN_SIZE + + .globl ftrace_call +ftrace_call: + bl ftrace_stub + ldmia sp!, {r0-r3, pc} + +#else + +ENTRY(mcount) + stmdb sp!, {r0-r3, lr} + ldr r0, =ftrace_trace_function + ldr r2, [r0] + adr r0, ftrace_stub + cmp r0, r2 + bne trace + ldmia sp!, {r0-r3, pc} + +trace: + ldr r1, [fp, #-4] + mov r0, lr + sub r0, r0, #MCOUNT_INSN_SIZE + mov lr, pc + mov pc, r2 + ldmia sp!, {r0-r3, pc} + +#endif /* CONFIG_DYNAMIC_FTRACE */ + + .globl ftrace_stub +ftrace_stub: + mov pc, lr + +#endif /* CONFIG_FTRACE */ + /*============================================================================= * SWI handler *----------------------------------------------------------------------------- diff --git a/arch/arm/kernel/ftrace.c b/arch/arm/kernel/ftrace.c new file mode 100644 index 00000000000..76d50e6091b --- /dev/null +++ b/arch/arm/kernel/ftrace.c @@ -0,0 +1,116 @@ +/* + * Dynamic function tracing support. + * + * Copyright (C) 2008 Abhishek Sagar <sagar.abhishek@gmail.com> + * + * For licencing details, see COPYING. + * + * Defines low-level handling of mcount calls when the kernel + * is compiled with the -pg flag. When using dynamic ftrace, the + * mcount call-sites get patched lazily with NOP till they are + * enabled. All code mutation routines here take effect atomically. + */ + +#include <linux/ftrace.h> + +#include <asm/cacheflush.h> +#include <asm/ftrace.h> + +#define PC_OFFSET 8 +#define BL_OPCODE 0xeb000000 +#define BL_OFFSET_MASK 0x00ffffff + +static unsigned long bl_insn; +static const unsigned long NOP = 0xe1a00000; /* mov r0, r0 */ + +unsigned char *ftrace_nop_replace(void) +{ + return (char *)&NOP; +} + +/* construct a branch (BL) instruction to addr */ +unsigned char *ftrace_call_replace(unsigned long pc, unsigned long addr) +{ + long offset; + + offset = (long)addr - (long)(pc + PC_OFFSET); + if (unlikely(offset < -33554432 || offset > 33554428)) { + /* Can't generate branches that far (from ARM ARM). Ftrace + * doesn't generate branches outside of kernel text. + */ + WARN_ON_ONCE(1); + return NULL; + } + offset = (offset >> 2) & BL_OFFSET_MASK; + bl_insn = BL_OPCODE | offset; + return (unsigned char *)&bl_insn; +} + +int ftrace_modify_code(unsigned long pc, unsigned char *old_code, + unsigned char *new_code) +{ + unsigned long err = 0, replaced = 0, old, new; + + old = *(unsigned long *)old_code; + new = *(unsigned long *)new_code; + + __asm__ __volatile__ ( + "1: ldr %1, [%2] \n" + " cmp %1, %4 \n" + "2: streq %3, [%2] \n" + " cmpne %1, %3 \n" + " movne %0, #2 \n" + "3:\n" + + ".section .fixup, \"ax\"\n" + "4: mov %0, #1 \n" + " b 3b \n" + ".previous\n" + + ".section __ex_table, \"a\"\n" + " .long 1b, 4b \n" + " .long 2b, 4b \n" + ".previous\n" + + : "=r"(err), "=r"(replaced) + : "r"(pc), "r"(new), "r"(old), "0"(err), "1"(replaced) + : "memory"); + + if (!err && (replaced == old)) + flush_icache_range(pc, pc + MCOUNT_INSN_SIZE); + + return err; +} + +int ftrace_update_ftrace_func(ftrace_func_t func) +{ + int ret; + unsigned long pc, old; + unsigned char *new; + + pc = (unsigned long)&ftrace_call; + memcpy(&old, &ftrace_call, MCOUNT_INSN_SIZE); + new = ftrace_call_replace(pc, (unsigned long)func); + ret = ftrace_modify_code(pc, (unsigned char *)&old, new); + return ret; +} + +int ftrace_mcount_set(unsigned long *data) +{ + unsigned long pc, old; + unsigned long *addr = data; + unsigned char *new; + + pc = (unsigned long)&mcount_call; + memcpy(&old, &mcount_call, MCOUNT_INSN_SIZE); + new = ftrace_call_replace(pc, *addr); + *addr = ftrace_modify_code(pc, (unsigned char *)&old, new); + return 0; +} + +/* run from kstop_machine */ +int __init ftrace_dyn_arch_init(void *data) +{ + ftrace_mcount_set(data); + return 0; +} diff --git a/arch/arm/kernel/kprobes.c b/arch/arm/kernel/kprobes.c index 5593dd20721..5ee39e10c8d 100644 --- a/arch/arm/kernel/kprobes.c +++ b/arch/arm/kernel/kprobes.c @@ -274,7 +274,7 @@ int __kprobes kprobe_exceptions_notify(struct notifier_block *self, * for kretprobe handlers which should normally be interested in r0 only * anyway. */ -static void __attribute__((naked)) __kprobes kretprobe_trampoline(void) +void __naked __kprobes kretprobe_trampoline(void) { __asm__ __volatile__ ( "stmdb sp!, {r0 - r11} \n\t" diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 3934e265940..a5e9912e2d3 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -105,11 +105,13 @@ config ARCH_NO_VIRT_TO_BUS config PPC bool default y + select HAVE_DYNAMIC_FTRACE + select HAVE_FTRACE select HAVE_IDE - select HAVE_OPROFILE select HAVE_KPROBES select HAVE_KRETPROBES select HAVE_LMB + select HAVE_OPROFILE config EARLY_PRINTK bool diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile index 2346d271fbf..f3f5e264143 100644 --- a/arch/powerpc/kernel/Makefile +++ b/arch/powerpc/kernel/Makefile @@ -12,6 +12,18 @@ CFLAGS_prom_init.o += -fPIC CFLAGS_btext.o += -fPIC endif +ifdef CONFIG_FTRACE +# Do not trace early boot code +CFLAGS_REMOVE_cputable.o = -pg +CFLAGS_REMOVE_prom_init.o = -pg + +ifdef CONFIG_DYNAMIC_FTRACE +# dynamic ftrace setup. +CFLAGS_REMOVE_ftrace.o = -pg +endif + +endif + obj-y := cputable.o ptrace.o syscalls.o \ irq.o align.o signal_32.o pmc.o vdso.o \ init_task.o process.o systbl.o idle.o \ @@ -78,6 +90,8 @@ obj-$(CONFIG_KEXEC) += machine_kexec.o crash.o \ obj-$(CONFIG_AUDIT) += audit.o obj64-$(CONFIG_AUDIT) += compat_audit.o +obj-$(CONFIG_DYNAMIC_FTRACE) += ftrace.o + obj-$(CONFIG_8XX_MINIMAL_FPEMU) += softemu8xx.o ifneq ($(CONFIG_PPC_INDIRECT_IO),y) diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S index 0c8614d9875..7231a708af0 100644 --- a/arch/powerpc/kernel/entry_32.S +++ b/arch/powerpc/kernel/entry_32.S @@ -30,6 +30,7 @@ #include <asm/ppc_asm.h> #include <asm/asm-offsets.h> #include <asm/unistd.h> +#include <asm/ftrace.h> #undef SHOW_SYSCALLS #undef SHOW_SYSCALLS_TASK @@ -1035,3 +1036,129 @@ machine_check_in_rtas: /* XXX load up BATs and panic */ #endif /* CONFIG_PPC_RTAS */ + +#ifdef CONFIG_FTRACE +#ifdef CONFIG_DYNAMIC_FTRACE +_GLOBAL(mcount) +_GLOBAL(_mcount) + stwu r1,-48(r1) + stw r3, 12(r1) + stw r4, 16(r1) + stw r5, 20(r1) + stw r6, 24(r1) + mflr r3 + stw r7, 28(r1) + mfcr r5 + stw r8, 32(r1) + stw r9, 36(r1) + stw r10,40(r1) + stw r3, 44(r1) + stw r5, 8(r1) + subi r3, r3, MCOUNT_INSN_SIZE + .globl mcount_call +mcount_call: + bl ftrace_stub + nop + lwz r6, 8(r1) + lwz r0, 44(r1) + lwz r3, 12(r1) + mtctr r0 + lwz r4, 16(r1) + mtcr r6 + lwz r5, 20(r1) + lwz r6, 24(r1) + lwz r0, 52(r1) + lwz r7, 28(r1) + lwz r8, 32(r1) + mtlr r0 + lwz r9, 36(r1) + lwz r10,40(r1) + addi r1, r1, 48 + bctr + +_GLOBAL(ftrace_caller) + /* Based off of objdump optput from glibc */ + stwu r1,-48(r1) + stw r3, 12(r1) + stw r4, 16(r1) + stw r5, 20(r1) + stw r6, 24(r1) + mflr r3 + lwz r4, 52(r1) + mfcr r5 + stw r7, 28(r1) + stw r8, 32(r1) + stw r9, 36(r1) + stw r10,40(r1) + stw r3, 44(r1) + stw r5, 8(r1) + subi r3, r3, MCOUNT_INSN_SIZE +.globl ftrace_call +ftrace_call: + bl ftrace_stub + nop + lwz r6, 8(r1) + lwz r0, 44(r1) + lwz r3, 12(r1) + mtctr r0 + lwz r4, 16(r1) + mtcr r6 + lwz r5, 20(r1) + lwz r6, 24(r1) + lwz r0, 52(r1) + lwz r7, 28(r1) + lwz r8, 32(r1) + mtlr r0 + lwz r9, 36(r1) + lwz r10,40(r1) + addi r1, r1, 48 + bctr +#else +_GLOBAL(mcount) +_GLOBAL(_mcount) + stwu r1,-48(r1) + stw r3, 12(r1) + stw r4, 16(r1) + stw r5, 20(r1) + stw r6, 24(r1) + mflr r3 + lwz r4, 52(r1) + mfcr r5 + stw r7, 28(r1) + stw r8, 32(r1) + stw r9, 36(r1) + stw r10,40(r1) + stw r3, 44(r1) + stw r5, 8(r1) + + subi r3, r3, MCOUNT_INSN_SIZE + LOAD_REG_ADDR(r5, ftrace_trace_function) + lwz r5,0(r5) + + mtctr r5 + bctrl + + nop + + lwz r6, 8(r1) + lwz r0, 44(r1) + lwz r3, 12(r1) + mtctr r0 + lwz r4, 16(r1) + mtcr r6 + lwz r5, 20(r1) + lwz r6, 24(r1) + lwz r0, 52(r1) + lwz r7, 28(r1) + lwz r8, 32(r1) + mtlr r0 + lwz r9, 36(r1) + lwz r10,40(r1) + addi r1, r1, 48 + bctr +#endif + +_GLOBAL(ftrace_stub) + blr + +#endif /* CONFIG_MCOUNT */ diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S index c0db5b769e5..2f511a969d2 100644 --- a/arch/powerpc/kernel/entry_64.S +++ b/arch/powerpc/kernel/entry_64.S @@ -31,6 +31,7 @@ #include <asm/bug.h> #include <asm/ptrace.h> #include <asm/irqflags.h> +#include <asm/ftrace.h> /* * System calls. @@ -870,3 +871,67 @@ _GLOBAL(enter_prom) ld r0,16(r1) mtlr r0 blr + +#ifdef CONFIG_FTRACE +#ifdef CONFIG_DYNAMIC_FTRACE +_GLOBAL(mcount) +_GLOBAL(_mcount) + /* Taken from output of objdump from lib64/glibc */ + mflr r3 + stdu r1, -112(r1) + std r3, 128(r1) + subi r3, r3, MCOUNT_INSN_SIZE + .globl mcount_call +mcount_call: + bl ftrace_stub + nop + ld r0, 128(r1) + mtlr r0 + addi r1, r1, 112 + blr + +_GLOBAL(ftrace_caller) + /* Taken from output of objdump from lib64/glibc */ + mflr r3 + ld r11, 0(r1) + stdu r1, -112(r1) + std r3, 128(r1) + ld r4, 16(r11) + subi r3, r3, MCOUNT_INSN_SIZE +.globl ftrace_call +ftrace_call: + bl ftrace_stub + nop + ld r0, 128(r1) + mtlr r0 + addi r1, r1, 112 +_GLOBAL(ftrace_stub) + blr +#else +_GLOBAL(mcount) + blr + +_GLOBAL(_mcount) + /* Taken from output of objdump from lib64/glibc */ + mflr r3 + ld r11, 0(r1) + stdu r1, -112(r1) + std r3, 128(r1) + ld r4, 16(r11) + + subi r3, r3, MCOUNT_INSN_SIZE + LOAD_REG_ADDR(r5,ftrace_trace_function) + ld r5,0(r5) + ld r5,0(r5) + mtctr r5 + bctrl + + nop + ld r0, 128(r1) + mtlr r0 + addi r1, r1, 112 +_GLOBAL(ftrace_stub) + blr + +#endif +#endif diff --git a/arch/powerpc/kernel/ftrace.c b/arch/powerpc/kernel/ftrace.c new file mode 100644 index 00000000000..3855ceb937b --- /dev/null +++ b/arch/powerpc/kernel/ftrace.c @@ -0,0 +1,154 @@ +/* + * Code for replacing ftrace calls with jumps. + * + * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com> + * + * Thanks goes out to P.A. Semi, Inc for supplying me with a PPC64 box. + * + */ + +#include <linux/spinlock.h> +#include <linux/hardirq.h> +#include <linux/ftrace.h> +#include <linux/percpu.h> +#include <linux/init.h> +#include <linux/list.h> + +#include <asm/cacheflush.h> +#include <asm/ftrace.h> + + +static unsigned int ftrace_nop = 0x60000000; + +#ifdef CONFIG_PPC32 +# define GET_ADDR(addr) addr +#else +/* PowerPC64's functions are data that points to the functions */ +# define GET_ADDR(addr) *(unsigned long *)addr +#endif + + +static unsigned int notrace ftrace_calc_offset(long ip, long addr) +{ + return (int)(addr - ip); +} + +notrace unsigned char *ftrace_nop_replace(void) +{ + return (char *)&ftrace_nop; +} + +notrace unsigned char *ftrace_call_replace(unsigned long ip, unsigned long addr) +{ + static unsigned int op; + + /* + * It would be nice to just use create_function_call, but that will + * update the code itself. Here we need to just return the + * instruction that is going to be modified, without modifying the + * code. + */ + addr = GET_ADDR(addr); + + /* Set to "bl addr" */ + op = 0x48000001 | (ftrace_calc_offset(ip, addr) & 0x03fffffc); + + /* + * No locking needed, this must be called via kstop_machine + * which in essence is like running on a uniprocessor machine. + */ + return (unsigned char *)&op; +} + +#ifdef CONFIG_PPC64 +# define _ASM_ALIGN " .align 3 " +# define _ASM_PTR " .llong " +#else +# define _ASM_ALIGN " .align 2 " +# define _ASM_PTR " .long " +#endif + +notrace int +ftrace_modify_code(unsigned long ip, unsigned char *old_code, + unsigned char *new_code) +{ + unsigned replaced; + unsigned old = *(unsigned *)old_code; + unsigned new = *(unsigned *)new_code; + int faulted = 0; + + /* + * Note: Due to modules and __init, code can + * disappear and change, we need to protect against faulting + * as well as code changing. + * + * No real locking needed, this code is run through + * kstop_machine. + */ + asm volatile ( + "1: lwz %1, 0(%2)\n" + " cmpw %1, %5\n" + " bne 2f\n" + " stwu %3, 0(%2)\n" + "2:\n" + ".section .fixup, \"ax\"\n" + "3: li %0, 1\n" + " b 2b\n" + ".previous\n" + ".section __ex_table,\"a\"\n" + _ASM_ALIGN "\n" + _ASM_PTR "1b, 3b\n" + ".previous" + : "=r"(faulted), "=r"(replaced) + : "r"(ip), "r"(new), + "0"(faulted), "r"(old) + : "memory"); + + if (replaced != old && replaced != new) + faulted = 2; + + if (!faulted) + flush_icache_range(ip, ip + 8); + + return faulted; +} + +notrace int ftrace_update_ftrace_func(ftrace_func_t func) +{ + unsigned long ip = (unsigned long)(&ftrace_call); + unsigned char old[MCOUNT_INSN_SIZE], *new; + int ret; + + memcpy(old, &ftrace_call, MCOUNT_INSN_SIZE); + new = ftrace_call_replace(ip, (unsigned long)func); + ret = ftrace_modify_code(ip, old, new); + + return ret; +} + +notrace int ftrace_mcount_set(unsigned long *data) +{ + unsigned long ip = (long)(&mcount_call); + unsigned long *addr = data; + unsigned char old[MCOUNT_INSN_SIZE], *new; + + /* + * Replace the mcount stub with a pointer to the + * ip recorder function. + */ + memcpy(old, &mcount_call, MCOUNT_INSN_SIZE); + new = ftrace_call_replace(ip, *addr); + *addr = ftrace_modify_code(ip, old, new); + + return 0; +} + +int __init ftrace_dyn_arch_init(void *data) +{ + /* This is running in kstop_machine */ + + ftrace_mcount_set(data); + + return 0; +} + diff --git a/arch/powerpc/kernel/io.c b/arch/powerpc/kernel/io.c index e31aca9208e..1882bf419fa 100644 --- a/arch/powerpc/kernel/io.c +++ b/arch/powerpc/kernel/io.c @@ -120,7 +120,8 @@ EXPORT_SYMBOL(_outsl_ns); #define IO_CHECK_ALIGN(v,a) ((((unsigned long)(v)) & ((a) - 1)) == 0) -void _memset_io(volatile void __iomem *addr, int c, unsigned long n) +notrace void +_memset_io(volatile void __iomem *addr, int c, unsigned long n) { void *p = (void __force *)addr; u32 lc = c; diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c index bcc249d90c4..dcc946e6709 100644 --- a/arch/powerpc/kernel/irq.c +++ b/arch/powerpc/kernel/irq.c @@ -98,7 +98,7 @@ EXPORT_SYMBOL(irq_desc); int distribute_irqs = 1; -static inline unsigned long get_hard_enabled(void) +static inline notrace unsigned long get_hard_enabled(void) { unsigned long enabled; @@ -108,13 +108,13 @@ static inline unsigned long get_hard_enabled(void) return enabled; } -static inline void set_soft_enabled(unsigned long enable) +static inline notrace void set_soft_enabled(unsigned long enable) { __asm__ __volatile__("stb %0,%1(13)" : : "r" (enable), "i" (offsetof(struct paca_struct, soft_enabled))); } -void raw_local_irq_restore(unsigned long en) +notrace void raw_local_irq_restore(unsigned long en) { /* * get_paca()->soft_enabled = en; diff --git a/arch/powerpc/kernel/ppc_ksyms.c b/arch/powerpc/kernel/ppc_ksyms.c index d3ac631cbd2..a8d02506468 100644 --- a/arch/powerpc/kernel/ppc_ksyms.c +++ b/arch/powerpc/kernel/ppc_ksyms.c @@ -42,6 +42,7 @@ #include <asm/div64.h> #include <asm/signal.h> #include <asm/dcr.h> +#include <asm/ftrace.h> #ifdef CONFIG_PPC32 extern void transfer_to_handler(void); @@ -67,6 +68,10 @@ EXPORT_SYMBOL(single_step_exception); EXPORT_SYMBOL(sys_sigreturn); #endif +#ifdef CONFIG_FTRACE +EXPORT_SYMBOL(_mcount); +#endif + EXPORT_SYMBOL(strcpy); EXPORT_SYMBOL(strncpy); EXPORT_SYMBOL(strcat); diff --git a/arch/powerpc/kernel/setup_32.c b/arch/powerpc/kernel/setup_32.c index 5112a4aa801..19e8fcb9cea 100644 --- a/arch/powerpc/kernel/setup_32.c +++ b/arch/powerpc/kernel/setup_32.c @@ -81,7 +81,7 @@ int ucache_bsize; * from the address that it was linked at, so we must use RELOC/PTRRELOC * to access static data (including strings). -- paulus */ -unsigned long __init early_init(unsigned long dt_ptr) +notrace unsigned long __init early_init(unsigned long dt_ptr) { unsigned long offset = reloc_offset(); struct cpu_spec *spec; @@ -111,7 +111,7 @@ unsigned long __init early_init(unsigned long dt_ptr) * This is called very early on the boot process, after a minimal * MMU environment has been set up but before MMU_init is called. */ -void __init machine_init(unsigned long dt_ptr, unsigned long phys) +notrace void __init machine_init(unsigned long dt_ptr, unsigned long phys) { /* Enable early debugging if any specified (see udbg.h) */ udbg_early_init(); @@ -133,7 +133,7 @@ void __init machine_init(unsigned long dt_ptr, unsigned long phys) #ifdef CONFIG_BOOKE_WDT /* Checks wdt=x and wdt_period=xx command-line option */ -int __init early_parse_wdt(char *p) +notrace int __init early_parse_wdt(char *p) { if (p && strncmp(p, "0", 1) != 0) booke_wdt_enabled = 1; diff --git a/arch/powerpc/platforms/powermac/Makefile b/arch/powerpc/platforms/powermac/Makefile index 4d72c8f7215..89774177b20 100644 --- a/arch/powerpc/platforms/powermac/Makefile +++ b/arch/powerpc/platforms/powermac/Makefile @@ -1,5 +1,10 @@ CFLAGS_bootx_init.o += -fPIC +ifdef CONFIG_FTRACE +# Do not trace early boot code +CFLAGS_REMOVE_bootx_init.o = -pg +endif + obj-y += pic.o setup.o time.o feature.o pci.o \ sleep.o low_i2c.o cache.o pfunc_core.o \ pfunc_base.o diff --git a/arch/sparc64/Kconfig b/arch/sparc64/Kconfig index eb36f3b746b..fca9246470b 100644 --- a/arch/sparc64/Kconfig +++ b/arch/sparc64/Kconfig @@ -11,6 +11,8 @@ config SPARC config SPARC64 bool default y + select HAVE_DYNAMIC_FTRACE + select HAVE_FTRACE select HAVE_IDE select HAVE_LMB select HAVE_ARCH_KGDB diff --git a/arch/sparc64/Kconfig.debug b/arch/sparc64/Kconfig.debug index 6a4d28a4076..d6d32d178fc 100644 --- a/arch/sparc64/Kconfig.debug +++ b/arch/sparc64/Kconfig.debug @@ -33,7 +33,7 @@ config DEBUG_PAGEALLOC config MCOUNT bool - depends on STACK_DEBUG + depends on STACK_DEBUG || FTRACE default y config FRAME_POINTER diff --git a/arch/sparc64/kernel/Makefile b/arch/sparc64/kernel/Makefile index ec4f5ebb1ca..418b5782096 100644 --- a/arch/sparc64/kernel/Makefile +++ b/arch/sparc64/kernel/Makefile @@ -14,6 +14,7 @@ obj-y := process.o setup.o cpu.o idprom.o \ power.o sbus.o sparc64_ksyms.o chmc.o \ visemul.o prom.o of_device.o hvapi.o sstate.o mdesc.o +obj-$(CONFIG_DYNAMIC_FTRACE) += ftrace.o obj-$(CONFIG_STACKTRACE) += stacktrace.o obj-$(CONFIG_PCI) += ebus.o pci_common.o \ pci_psycho.o pci_sabre.o pci_schizo.o \ diff --git a/arch/sparc64/kernel/ftrace.c b/arch/sparc64/kernel/ftrace.c new file mode 100644 index 00000000000..4298d0aee71 --- /dev/null +++ b/arch/sparc64/kernel/ftrace.c @@ -0,0 +1,94 @@ +#include <linux/spinlock.h> +#include <linux/hardirq.h> +#include <linux/ftrace.h> +#include <linux/percpu.h> +#include <linux/init.h> +#include <linux/list.h> + +#include <asm/ftrace.h> + +static const u32 ftrace_nop = 0x01000000; + +notrace unsigned char *ftrace_nop_replace(void) +{ + return (char *)&ftrace_nop; +} + +notrace unsigned char *ftrace_call_replace(unsigned long ip, unsigned long addr) +{ + static u32 call; + s32 off; + + off = ((s32)addr - (s32)ip); + call = 0x40000000 | ((u32)off >> 2); + + return (unsigned char *) &call; +} + +notrace int +ftrace_modify_code(unsigned long ip, unsigned char *old_code, + unsigned char *new_code) +{ + u32 old = *(u32 *)old_code; + u32 new = *(u32 *)new_code; + u32 replaced; + int faulted; + + __asm__ __volatile__( + "1: cas [%[ip]], %[old], %[new]\n" + " flush %[ip]\n" + " mov 0, %[faulted]\n" + "2:\n" + " .section .fixup,#alloc,#execinstr\n" + " .align 4\n" + "3: sethi %%hi(2b), %[faulted]\n" + " jmpl %[faulted] + %%lo(2b), %%g0\n" + " mov 1, %[faulted]\n" + " .previous\n" + " .section __ex_table,\"a\"\n" + " .align 4\n" + " .word 1b, 3b\n" + " .previous\n" + : "=r" (replaced), [faulted] "=r" (faulted) + : [new] "0" (new), [old] "r" (old), [ip] "r" (ip) + : "memory"); + + if (replaced != old && replaced != new) + faulted = 2; + + return faulted; +} + +notrace int ftrace_update_ftrace_func(ftrace_func_t func) +{ + unsigned long ip = (unsigned long)(&ftrace_call); + unsigned char old[MCOUNT_INSN_SIZE], *new; + + memcpy(old, &ftrace_call, MCOUNT_INSN_SIZE); + new = ftrace_call_replace(ip, (unsigned long)func); + return ftrace_modify_code(ip, old, new); +} + +notrace int ftrace_mcount_set(unsigned long *data) +{ + unsigned long ip = (long)(&mcount_call); + unsigned long *addr = data; + unsigned char old[MCOUNT_INSN_SIZE], *new; + + /* + * Replace the mcount stub with a pointer to the + * ip recorder function. + */ + memcpy(old, &mcount_call, MCOUNT_INSN_SIZE); + new = ftrace_call_replace(ip, *addr); + *addr = ftrace_modify_code(ip, old, new); + + return 0; +} + + +int __init ftrace_dyn_arch_init(void *data) +{ + ftrace_mcount_set(data); + return 0; +} diff --git a/arch/sparc64/kernel/sparc64_ksyms.c b/arch/sparc64/kernel/sparc64_ksyms.c index 8ac0b99f2c5..49d3ea50c24 100644 --- a/arch/sparc64/kernel/sparc64_ksyms.c +++ b/arch/sparc64/kernel/sparc64_ksyms.c @@ -53,6 +53,7 @@ #include <asm/ns87303.h> #include <asm/timer.h> #include <asm/cpudata.h> +#include <asm/ftrace.h> struct poll { int fd; @@ -111,8 +112,7 @@ EXPORT_SYMBOL(__write_trylock); EXPORT_SYMBOL(smp_call_function); #endif /* CONFIG_SMP */ -#if defined(CONFIG_MCOUNT) -extern void _mcount(void); +#ifdef CONFIG_MCOUNT EXPORT_SYMBOL(_mcount); #endif diff --git a/arch/sparc64/lib/mcount.S b/arch/sparc64/lib/mcount.S index 9e4534b485c..7735a7a6053 100644 --- a/arch/sparc64/lib/mcount.S +++ b/arch/sparc64/lib/mcount.S @@ -28,10 +28,13 @@ ovstack: .skip OVSTACKSIZE #endif .text - .align 32 - .globl mcount, _mcount -mcount: + .align 32 + .globl _mcount + .type _mcount,#function + .globl mcount + .type mcount,#function _mcount: +mcount: #ifdef CONFIG_STACK_DEBUG /* * Check whether %sp is dangerously low. @@ -55,6 +58,53 @@ _mcount: or %g3, %lo(panicstring), %o0 call prom_halt nop +1: +#endif +#ifdef CONFIG_FTRACE +#ifdef CONFIG_DYNAMIC_FTRACE + mov %o7, %o0 + .globl mcount_call +mcount_call: + call ftrace_stub + mov %o0, %o7 +#else + sethi %hi(ftrace_trace_function), %g1 + sethi %hi(ftrace_stub), %g2 + ldx [%g1 + %lo(ftrace_trace_function)], %g1 + or %g2, %lo(ftrace_stub), %g2 + cmp %g1, %g2 + be,pn %icc, 1f + mov %i7, %o1 + jmpl %g1, %g0 + mov %o7, %o0 + /* not reached */ +1: #endif -1: retl +#endif + retl nop + .size _mcount,.-_mcount + .size mcount,.-mcount + +#ifdef CONFIG_FTRACE + .globl ftrace_stub + .type ftrace_stub,#function +ftrace_stub: + retl + nop + .size ftrace_stub,.-ftrace_stub +#ifdef CONFIG_DYNAMIC_FTRACE + .globl ftrace_caller + .type ftrace_caller,#function +ftrace_caller: + mov %i7, %o1 + mov %o7, %o0 + .globl ftrace_call +ftrace_call: + call ftrace_stub + mov %o0, %o7 + retl + nop + .size ftrace_caller,.-ftrace_caller +#endif +#endif diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 2cfccc987a2..6958d6bcaf7 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -23,6 +23,8 @@ config X86 select HAVE_OPROFILE select HAVE_KPROBES select HAVE_KRETPROBES + select HAVE_DYNAMIC_FTRACE + select HAVE_FTRACE select HAVE_KVM if ((X86_32 && !X86_VOYAGER && !X86_VISWS && !X86_NUMAQ) || X86_64) select HAVE_ARCH_KGDB if !X86_VOYAGER diff --git a/arch/x86/Kconfig.debug b/arch/x86/Kconfig.debug index acc0271920f..5236621350b 100644 --- a/arch/x86/Kconfig.debug +++ b/arch/x86/Kconfig.debug @@ -171,6 +171,34 @@ config IOMMU_LEAK Add a simple leak tracer to the IOMMU code. This is useful when you are debugging a buggy device driver that leaks IOMMU mappings. +config MMIOTRACE_HOOKS + bool + +config MMIOTRACE + bool "Memory mapped IO tracing" + depends on DEBUG_KERNEL && PCI + select TRACING + select MMIOTRACE_HOOKS + default y + help + Mmiotrace traces Memory Mapped I/O access and is meant for + debugging and reverse engineering. It is called from the ioremap + implementation and works via page faults. Tracing is disabled by + default and can be enabled at run-time. + + See Documentation/tracers/mmiotrace.txt. + If you are not helping to develop drivers, say N. + +config MMIOTRACE_TEST + tristate "Test module for mmiotrace" + depends on MMIOTRACE && m + help + This is a dumb module for testing mmiotrace. It is very dangerous + as it will write garbage to IO memory starting at a given address. + However, it should be safe to use on e.g. unused portion of VRAM. + + Say N, unless you absolutely know what you are doing. + # # IO delay types: # diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile index 55ff016e9f6..5112c84f542 100644 --- a/arch/x86/kernel/Makefile +++ b/arch/x86/kernel/Makefile @@ -6,6 +6,13 @@ extra-y := head_$(BITS).o head$(BITS).o head.o init_task.o vmlinu CPPFLAGS_vmlinux.lds += -U$(UTS_MACHINE) +ifdef CONFIG_FTRACE +# Do not profile debug utilities +CFLAGS_REMOVE_tsc_64.o = -pg +CFLAGS_REMOVE_tsc_32.o = -pg +CFLAGS_REMOVE_rtc.o = -pg +endif + # # vsyscalls (which work on the user stack) should have # no stack-protector checks: @@ -57,6 +64,7 @@ obj-$(CONFIG_X86_MPPARSE) += mpparse.o obj-$(CONFIG_X86_LOCAL_APIC) += apic_$(BITS).o nmi.o obj-$(CONFIG_X86_IO_APIC) += io_apic_$(BITS).o obj-$(CONFIG_X86_REBOOTFIXUPS) += reboot_fixups_32.o +obj-$(CONFIG_DYNAMIC_FTRACE) += ftrace.o obj-$(CONFIG_KEXEC) += machine_kexec_$(BITS).o obj-$(CONFIG_KEXEC) += relocate_kernel_$(BITS).o crash.o obj-$(CONFIG_CRASH_DUMP) += crash_dump_$(BITS).o diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c index 65c7857a90d..2763cb37b55 100644 --- a/arch/x86/kernel/alternative.c +++ b/arch/x86/kernel/alternative.c @@ -1,6 +1,6 @@ #include <linux/module.h> #include <linux/sched.h> -#include <linux/spinlock.h> +#include <linux/mutex.h> #include <linux/list.h> #include <linux/kprobes.h> #include <linux/mm.h> @@ -143,7 +143,7 @@ static const unsigned char *const p6_nops[ASM_NOP_MAX+1] = { #ifdef CONFIG_X86_64 extern char __vsyscall_0; -static inline const unsigned char*const * find_nop_table(void) +const unsigned char *const *find_nop_table(void) { return boot_cpu_data.x86_vendor != X86_VENDOR_INTEL || boot_cpu_data.x86 < 6 ? k8_nops : p6_nops; @@ -162,7 +162,7 @@ static const struct nop { { -1, NULL } }; -static const unsigned char*const * find_nop_table(void) +const unsigned char *const *find_nop_table(void) { const unsigned char *const *noptable = intel_nops; int i; @@ -279,7 +279,7 @@ struct smp_alt_module { struct list_head next; }; static LIST_HEAD(smp_alt_modules); -static DEFINE_SPINLOCK(smp_alt); +static DEFINE_MUTEX(smp_alt); static int smp_mode = 1; /* protected by smp_alt */ void alternatives_smp_module_add(struct module *mod, char *name, @@ -312,12 +312,12 @@ void alternatives_smp_module_add(struct module *mod, char *name, __func__, smp->locks, smp->locks_end, smp->text, smp->text_end, smp->name); - spin_lock(&smp_alt); + mutex_lock(&smp_alt); list_add_tail(&smp->next, &smp_alt_modules); if (boot_cpu_has(X86_FEATURE_UP)) alternatives_smp_unlock(smp->locks, smp->locks_end, smp->text, smp->text_end); - spin_unlock(&smp_alt); + mutex_unlock(&smp_alt); } void alternatives_smp_module_del(struct module *mod) @@ -327,17 +327,17 @@ void alternatives_smp_module_del(struct module *mod) if (smp_alt_once || noreplace_smp) return; - spin_lock(&smp_alt); + mutex_lock(&smp_alt); list_for_each_entry(item, &smp_alt_modules, next) { if (mod != item->mod) continue; list_del(&item->next); - spin_unlock(&smp_alt); + mutex_unlock(&smp_alt); DPRINTK("%s: %s\n", __func__, item->name); kfree(item); return; } - spin_unlock(&smp_alt); + mutex_unlock(&smp_alt); } void alternatives_smp_switch(int smp) @@ -359,7 +359,7 @@ void alternatives_smp_switch(int smp) return; BUG_ON(!smp && (num_online_cpus() > 1)); - spin_lock(&smp_alt); + mutex_lock(&smp_alt); /* * Avoid unnecessary switches because it forces JIT based VMs to @@ -383,7 +383,7 @@ void alternatives_smp_switch(int smp) mod->text, mod->text_end); } smp_mode = smp; - spin_unlock(&smp_alt); + mutex_unlock(&smp_alt); } #endif diff --git a/arch/x86/kernel/entry_32.S b/arch/x86/kernel/entry_32.S index cfe28a71543..6bc07f0f120 100644 --- a/arch/x86/kernel/entry_32.S +++ b/arch/x86/kernel/entry_32.S @@ -51,6 +51,7 @@ #include <asm/percpu.h> #include <asm/dwarf2.h> #include <asm/processor-flags.h> +#include <asm/ftrace.h> #include <asm/irq_vectors.h> /* @@ -1111,6 +1112,77 @@ ENDPROC(xen_failsafe_callback) #endif /* CONFIG_XEN */ +#ifdef CONFIG_FTRACE +#ifdef CONFIG_DYNAMIC_FTRACE + +ENTRY(mcount) + pushl %eax + pushl %ecx + pushl %edx + movl 0xc(%esp), %eax + subl $MCOUNT_INSN_SIZE, %eax + +.globl mcount_call +mcount_call: + call ftrace_stub + + popl %edx + popl %ecx + popl %eax + + ret +END(mcount) + +ENTRY(ftrace_caller) + pushl %eax + pushl %ecx + pushl %edx + movl 0xc(%esp), %eax + movl 0x4(%ebp), %edx + subl $MCOUNT_INSN_SIZE, %eax + +.globl ftrace_call +ftrace_call: + call ftrace_stub + + popl %edx + popl %ecx + popl %eax + +.globl ftrace_stub +ftrace_stub: + ret +END(ftrace_caller) + +#else /* ! CONFIG_DYNAMIC_FTRACE */ + +ENTRY(mcount) + cmpl $ftrace_stub, ftrace_trace_function + jnz trace +.globl ftrace_stub +ftrace_stub: + ret + + /* taken from glibc */ +trace: + pushl %eax + pushl %ecx + pushl %edx + movl 0xc(%esp), %eax + movl 0x4(%ebp), %edx + subl $MCOUNT_INSN_SIZE, %eax + + call *ftrace_trace_function + + popl %edx + popl %ecx + popl %eax + + jmp ftrace_stub +END(mcount) +#endif /* CONFIG_DYNAMIC_FTRACE */ +#endif /* CONFIG_FTRACE */ + .section .rodata,"a" #include "syscall_table_32.S" diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S index bb4e22f4892..ba41bf42748 100644 --- a/arch/x86/kernel/entry_64.S +++ b/arch/x86/kernel/entry_64.S @@ -51,9 +51,115 @@ #include <asm/page.h> #include <asm/irqflags.h> #include <asm/paravirt.h> +#include <asm/ftrace.h> .code64 +#ifdef CONFIG_FTRACE +#ifdef CONFIG_DYNAMIC_FTRACE +ENTRY(mcount) + + subq $0x38, %rsp + movq %rax, (%rsp) + movq %rcx, 8(%rsp) + movq %rdx, 16(%rsp) + movq %rsi, 24(%rsp) + movq %rdi, 32(%rsp) + movq %r8, 40(%rsp) + movq %r9, 48(%rsp) + + movq 0x38(%rsp), %rdi + subq $MCOUNT_INSN_SIZE, %rdi + +.globl mcount_call +mcount_call: + call ftrace_stub + + movq 48(%rsp), %r9 + movq 40(%rsp), %r8 + movq 32(%rsp), %rdi + movq 24(%rsp), %rsi + movq 16(%rsp), %rdx + movq 8(%rsp), %rcx + movq (%rsp), %rax + addq $0x38, %rsp + + retq +END(mcount) + +ENTRY(ftrace_caller) + + /* taken from glibc */ + subq $0x38, %rsp + movq %rax, (%rsp) + movq %rcx, 8(%rsp) + movq %rdx, 16(%rsp) + movq %rsi, 24(%rsp) + movq %rdi, 32(%rsp) + movq %r8, 40(%rsp) + movq %r9, 48(%rsp) + + movq 0x38(%rsp), %rdi + movq 8(%rbp), %rsi + subq $MCOUNT_INSN_SIZE, %rdi + +.globl ftrace_call +ftrace_call: + call ftrace_stub + + movq 48(%rsp), %r9 + movq 40(%rsp), %r8 + movq 32(%rsp), %rdi + movq 24(%rsp), %rsi + movq 16(%rsp), %rdx + movq 8(%rsp), %rcx + movq (%rsp), %rax + addq $0x38, %rsp + +.globl ftrace_stub +ftrace_stub: + retq +END(ftrace_caller) + +#else /* ! CONFIG_DYNAMIC_FTRACE */ +ENTRY(mcount) + cmpq $ftrace_stub, ftrace_trace_function + jnz trace +.globl ftrace_stub +ftrace_stub: + retq + +trace: + /* taken from glibc */ + subq $0x38, %rsp + movq %rax, (%rsp) + movq %rcx, 8(%rsp) + movq %rdx, 16(%rsp) + movq %rsi, 24(%rsp) + movq %rdi, 32(%rsp) + movq %r8, 40(%rsp) + movq %r9, 48(%rsp) + + movq 0x38(%rsp), %rdi + movq 8(%rbp), %rsi + subq $MCOUNT_INSN_SIZE, %rdi + + call *ftrace_trace_function + + movq 48(%rsp), %r9 + movq 40(%rsp), %r8 + movq 32(%rsp), %rdi + movq 24(%rsp), %rsi + movq 16(%rsp), %rdx + movq 8(%rsp), %rcx + movq (%rsp), %rax + addq $0x38, %rsp + + jmp ftrace_stub +END(mcount) +#endif /* CONFIG_DYNAMIC_FTRACE */ +#endif /* CONFIG_FTRACE */ + #ifndef CONFIG_PREEMPT #define retint_kernel retint_restore_args #endif diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c new file mode 100644 index 00000000000..ab115cd15fd --- /dev/null +++ b/arch/x86/kernel/ftrace.c @@ -0,0 +1,141 @@ +/* + * Code for replacing ftrace calls with jumps. + * + * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com> + * + * Thanks goes to Ingo Molnar, for suggesting the idea. + * Mathieu Desnoyers, for suggesting postponing the modifications. + * Arjan van de Ven, for keeping me straight, and explaining to me + * the dangers of modifying code on the run. + */ + +#include <linux/spinlock.h> +#include <linux/hardirq.h> +#include <linux/ftrace.h> +#include <linux/percpu.h> +#include <linux/init.h> +#include <linux/list.h> + +#include <asm/alternative.h> +#include <asm/ftrace.h> + + +/* Long is fine, even if it is only 4 bytes ;-) */ +static long *ftrace_nop; + +union ftrace_code_union { + char code[MCOUNT_INSN_SIZE]; + struct { + char e8; + int offset; + } __attribute__((packed)); +}; + + +static int notrace ftrace_calc_offset(long ip, long addr) +{ + return (int)(addr - ip); +} + +notrace unsigned char *ftrace_nop_replace(void) +{ + return (char *)ftrace_nop; +} + +notrace unsigned char *ftrace_call_replace(unsigned long ip, unsigned long addr) +{ + static union ftrace_code_union calc; + + calc.e8 = 0xe8; + calc.offset = ftrace_calc_offset(ip + MCOUNT_INSN_SIZE, addr); + + /* + * No locking needed, this must be called via kstop_machine + * which in essence is like running on a uniprocessor machine. + */ + return calc.code; +} + +notrace int +ftrace_modify_code(unsigned long ip, unsigned char *old_code, + unsigned char *new_code) +{ + unsigned replaced; + unsigned old = *(unsigned *)old_code; /* 4 bytes */ + unsigned new = *(unsigned *)new_code; /* 4 bytes */ + unsigned char newch = new_code[4]; + int faulted = 0; + + /* + * Note: Due to modules and __init, code can + * disappear and change, we need to protect against faulting + * as well as code changing. + * + * No real locking needed, this code is run through + * kstop_machine. + */ + asm volatile ( + "1: lock\n" + " cmpxchg %3, (%2)\n" + " jnz 2f\n" + " movb %b4, 4(%2)\n" + "2:\n" + ".section .fixup, \"ax\"\n" + "3: movl $1, %0\n" + " jmp 2b\n" + ".previous\n" + _ASM_EXTABLE(1b, 3b) + : "=r"(faulted), "=a"(replaced) + : "r"(ip), "r"(new), "c"(newch), + "0"(faulted), "a"(old) + : "memory"); + sync_core(); + + if (replaced != old && replaced != new) + faulted = 2; + + return faulted; +} + +notrace int ftrace_update_ftrace_func(ftrace_func_t func) +{ + unsigned long ip = (unsigned long)(&ftrace_call); + unsigned char old[MCOUNT_INSN_SIZE], *new; + int ret; + + memcpy(old, &ftrace_call, MCOUNT_INSN_SIZE); + new = ftrace_call_replace(ip, (unsigned long)func); + ret = ftrace_modify_code(ip, old, new); + + return ret; +} + +notrace int ftrace_mcount_set(unsigned long *data) +{ + unsigned long ip = (long)(&mcount_call); + unsigned long *addr = data; + unsigned char old[MCOUNT_INSN_SIZE], *new; + + /* + * Replace the mcount stub with a pointer to the + * ip recorder function. + */ + memcpy(old, &mcount_call, MCOUNT_INSN_SIZE); + new = ftrace_call_replace(ip, *addr); + *addr = ftrace_modify_code(ip, old, new); + + return 0; +} + +int __init ftrace_dyn_arch_init(void *data) +{ + const unsigned char *const *noptable = find_nop_table(); + + /* This is running in kstop_machine */ + + ftrace_mcount_set(data); + + ftrace_nop = (unsigned long *)noptable[MCOUNT_INSN_SIZE]; + + return 0; +} diff --git a/arch/x86/kernel/i386_ksyms_32.c b/arch/x86/kernel/i386_ksyms_32.c index deb43785e92..dd7ebee446a 100644 --- a/arch/x86/kernel/i386_ksyms_32.c +++ b/arch/x86/kernel/i386_ksyms_32.c @@ -1,7 +1,14 @@ #include <linux/module.h> + #include <asm/checksum.h> -#include <asm/desc.h> #include <asm/pgtable.h> +#include <asm/desc.h> +#include <asm/ftrace.h> + +#ifdef CONFIG_FTRACE +/* mcount is defined in assembly */ +EXPORT_SYMBOL(mcount); +#endif /* Networking helper routines. */ EXPORT_SYMBOL(csum_partial_copy_generic); diff --git a/arch/x86/kernel/machine_kexec_32.c b/arch/x86/kernel/machine_kexec_32.c index f4960171bc6..8864230d55a 100644 --- a/arch/x86/kernel/machine_kexec_32.c +++ b/arch/x86/kernel/machine_kexec_32.c @@ -11,6 +11,8 @@ #include <linux/delay.h> #include <linux/init.h> #include <linux/numa.h> +#include <linux/ftrace.h> + #include <asm/pgtable.h> #include <asm/pgalloc.h> #include <asm/tlbflush.h> @@ -107,6 +109,8 @@ NORET_TYPE void machine_kexec(struct kimage *image) unsigned long page_list[PAGES_NR]; void *control_page; + tracer_disable(); + /* Interrupts aren't acceptable while we reboot */ local_irq_disable(); diff --git a/arch/x86/kernel/machine_kexec_64.c b/arch/x86/kernel/machine_kexec_64.c index 7830dc4a838..9dd9262693a 100644 --- a/arch/x86/kernel/machine_kexec_64.c +++ b/arch/x86/kernel/machine_kexec_64.c @@ -11,6 +11,8 @@ #include <linux/string.h> #include <linux/reboot.h> #include <linux/numa.h> +#include <linux/ftrace.h> + #include <asm/pgtable.h> #include <asm/tlbflush.h> #include <asm/mmu_context.h> @@ -184,6 +186,8 @@ NORET_TYPE void machine_kexec(struct kimage *image) unsigned long page_list[PAGES_NR]; void *control_page; + tracer_disable(); + /* Interrupts aren't acceptable while we reboot */ local_irq_disable(); diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c index 9a139f6c9df..0c3927accb0 100644 --- a/arch/x86/kernel/process_32.c +++ b/arch/x86/kernel/process_32.c @@ -142,7 +142,10 @@ void cpu_idle(void) local_irq_disable(); __get_cpu_var(irq_stat).idle_timestamp = jiffies; + /* Don't trace irqs off for idle */ + stop_critical_timings(); pm_idle(); + start_critical_timings(); } tick_nohz_restart_sched_tick(); preempt_enable_no_resched(); diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c index db5eb963e4d..a8e53626ac9 100644 --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -134,7 +134,10 @@ void cpu_idle(void) */ local_irq_disable(); enter_idle(); + /* Don't trace irqs off for idle */ + stop_critical_timings(); pm_idle(); + start_critical_timings(); /* In many cases the interrupt that ended idle has already called exit_idle. But some idle loops can be woken up without interrupt. */ diff --git a/arch/x86/kernel/vsyscall_64.c b/arch/x86/kernel/vsyscall_64.c index c87cbd84c3e..e50740d3231 100644 --- a/arch/x86/kernel/vsyscall_64.c +++ b/arch/x86/kernel/vsyscall_64.c @@ -42,7 +42,8 @@ #include <asm/topology.h> #include <asm/vgtod.h> -#define __vsyscall(nr) __attribute__ ((unused,__section__(".vsyscall_" #nr))) +#define __vsyscall(nr) \ + __attribute__ ((unused, __section__(".vsyscall_" #nr))) notrace #define __syscall_clobber "r11","cx","memory" /* diff --git a/arch/x86/kernel/x8664_ksyms_64.c b/arch/x86/kernel/x8664_ksyms_64.c index 2f306a82689..b545f371b5f 100644 --- a/arch/x86/kernel/x8664_ksyms_64.c +++ b/arch/x86/kernel/x8664_ksyms_64.c @@ -2,13 +2,20 @@ All C exports should go in the respective C files. */ #include <linux/module.h> -#include <net/checksum.h> #include <linux/smp.h> +#include <net/checksum.h> + #include <asm/processor.h> -#include <asm/uaccess.h> #include <asm/pgtable.h> +#include <asm/uaccess.h> #include <asm/desc.h> +#include <asm/ftrace.h> + +#ifdef CONFIG_FTRACE +/* mcount is defined in assembly */ +EXPORT_SYMBOL(mcount); +#endif EXPORT_SYMBOL(kernel_thread); diff --git a/arch/x86/lib/Makefile b/arch/x86/lib/Makefile index 83226e0a7ce..aa3fa411942 100644 --- a/arch/x86/lib/Makefile +++ b/arch/x86/lib/Makefile @@ -5,6 +5,7 @@ obj-$(CONFIG_SMP) := msr-on-cpu.o lib-y := delay.o +lib-y += thunk_$(BITS).o lib-y += usercopy_$(BITS).o getuser.o putuser.o lib-y += memcpy_$(BITS).o diff --git a/arch/x86/lib/thunk_32.S b/arch/x86/lib/thunk_32.S new file mode 100644 index 00000000000..650b11e00ec --- /dev/null +++ b/arch/x86/lib/thunk_32.S @@ -0,0 +1,47 @@ +/* + * Trampoline to trace irqs off. (otherwise CALLER_ADDR1 might crash) + * Copyright 2008 by Steven Rostedt, Red Hat, Inc + * (inspired by Andi Kleen's thunk_64.S) + * Subject to the GNU public license, v.2. No warranty of any kind. + */ + + #include <linux/linkage.h> + +#define ARCH_TRACE_IRQS_ON \ + pushl %eax; \ + pushl %ecx; \ + pushl %edx; \ + call trace_hardirqs_on; \ + popl %edx; \ + popl %ecx; \ + popl %eax; + +#define ARCH_TRACE_IRQS_OFF \ + pushl %eax; \ + pushl %ecx; \ + pushl %edx; \ + call trace_hardirqs_off; \ + popl %edx; \ + popl %ecx; \ + popl %eax; + +#ifdef CONFIG_TRACE_IRQFLAGS + /* put return address in eax (arg1) */ + .macro thunk_ra name,func + .globl \name +\name: + pushl %eax + pushl %ecx + pushl %edx + /* Place EIP in the arg1 */ + movl 3*4(%esp), %eax + call \func + popl %edx + popl %ecx + popl %eax + ret + .endm + + thunk_ra trace_hardirqs_on_thunk,trace_hardirqs_on_caller + thunk_ra trace_hardirqs_off_thunk,trace_hardirqs_off_caller +#endif diff --git a/arch/x86/lib/thunk_64.S b/arch/x86/lib/thunk_64.S index e009251d4e9..bf9a7d5a542 100644 --- a/arch/x86/lib/thunk_64.S +++ b/arch/x86/lib/thunk_64.S @@ -2,6 +2,7 @@ * Save registers before calling assembly functions. This avoids * disturbance of register allocation in some inline assembly constructs. * Copyright 2001,2002 by Andi Kleen, SuSE Labs. + * Added trace_hardirqs callers - Copyright 2007 Steven Rostedt, Red Hat, Inc. * Subject to the GNU public license, v.2. No warranty of any kind. */ @@ -42,8 +43,22 @@ #endif #ifdef CONFIG_TRACE_IRQFLAGS - thunk trace_hardirqs_on_thunk,trace_hardirqs_on - thunk trace_hardirqs_off_thunk,trace_hardirqs_off + /* put return address in rdi (arg1) */ + .macro thunk_ra name,func + .globl \name +\name: + CFI_STARTPROC + SAVE_ARGS + /* SAVE_ARGS pushs 9 elements */ + /* the next element would be the rip */ + movq 9*8(%rsp), %rdi + call \func + jmp restore + CFI_ENDPROC + .endm + + thunk_ra trace_hardirqs_on_thunk,trace_hardirqs_on_caller + thunk_ra trace_hardirqs_off_thunk,trace_hardirqs_off_caller #endif #ifdef CONFIG_DEBUG_LOCK_ALLOC diff --git a/arch/x86/mm/Makefile b/arch/x86/mm/Makefile index c107641cd39..9873716e9f7 100644 --- a/arch/x86/mm/Makefile +++ b/arch/x86/mm/Makefile @@ -8,6 +8,11 @@ obj-$(CONFIG_X86_PTDUMP) += dump_pagetables.o obj-$(CONFIG_HIGHMEM) += highmem_32.o +obj-$(CONFIG_MMIOTRACE_HOOKS) += kmmio.o +obj-$(CONFIG_MMIOTRACE) += mmiotrace.o +mmiotrace-y := pf_in.o mmio-mod.o +obj-$(CONFIG_MMIOTRACE_TEST) += testmmiotrace.o + ifeq ($(CONFIG_X86_32),y) obj-$(CONFIG_NUMA) += discontig_32.o else diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index d0f5fce77d9..455f3fe67b4 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -10,6 +10,7 @@ #include <linux/string.h> #include <linux/types.h> #include <linux/ptrace.h> +#include <linux/mmiotrace.h> #include <linux/mman.h> #include <linux/mm.h> #include <linux/smp.h> @@ -49,6 +50,16 @@ #define PF_RSVD (1<<3) #define PF_INSTR (1<<4) +static inline int kmmio_fault(struct pt_regs *regs, unsigned long addr) +{ +#ifdef CONFIG_MMIOTRACE_HOOKS + if (unlikely(is_kmmio_active())) + if (kmmio_handler(regs, addr) == 1) + return -1; +#endif + return 0; +} + static inline int notify_page_fault(struct pt_regs *regs) { #ifdef CONFIG_KPROBES @@ -598,6 +609,8 @@ void __kprobes do_page_fault(struct pt_regs *regs, unsigned long error_code) if (notify_page_fault(regs)) return; + if (unlikely(kmmio_fault(regs, address))) + return; /* * We fault-in kernel-space virtual memory on-demand. The diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c index 029e8cffca9..9689a5138e6 100644 --- a/arch/x86/mm/init_32.c +++ b/arch/x86/mm/init_32.c @@ -1035,6 +1035,8 @@ void mark_rodata_ro(void) unsigned long start = PFN_ALIGN(_text); unsigned long size = PFN_ALIGN(_etext) - start; +#ifndef CONFIG_DYNAMIC_FTRACE + /* Dynamic tracing modifies the kernel text section */ set_pages_ro(virt_to_page(start), size >> PAGE_SHIFT); printk(KERN_INFO "Write protecting the kernel text: %luk\n", size >> 10); @@ -1047,6 +1049,8 @@ void mark_rodata_ro(void) printk(KERN_INFO "Testing CPA: write protecting again\n"); set_pages_ro(virt_to_page(start), size>>PAGE_SHIFT); #endif +#endif /* CONFIG_DYNAMIC_FTRACE */ + start += size; size = (unsigned long)__end_rodata - start; set_pages_ro(virt_to_page(start), size >> PAGE_SHIFT); diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c index a25cc6fa220..27de2435e00 100644 --- a/arch/x86/mm/init_64.c +++ b/arch/x86/mm/init_64.c @@ -991,6 +991,13 @@ EXPORT_SYMBOL_GPL(rodata_test_data); void mark_rodata_ro(void) { unsigned long start = PFN_ALIGN(_stext), end = PFN_ALIGN(__end_rodata); + unsigned long rodata_start = + ((unsigned long)__start_rodata + PAGE_SIZE - 1) & PAGE_MASK; + +#ifdef CONFIG_DYNAMIC_FTRACE + /* Dynamic tracing modifies the kernel text section */ + start = rodata_start; +#endif printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n", (end - start) >> 10); @@ -1000,8 +1007,7 @@ void mark_rodata_ro(void) * The rodata section (but not the kernel text!) should also be * not-executable. */ - start = ((unsigned long)__start_rodata + PAGE_SIZE - 1) & PAGE_MASK; - set_memory_nx(start, (end - start) >> PAGE_SHIFT); + set_memory_nx(rodata_start, (end - rodata_start) >> PAGE_SHIFT); rodata_test(); diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c index 115f13ee40c..24c1d3c3018 100644 --- a/arch/x86/mm/ioremap.c +++ b/arch/x86/mm/ioremap.c @@ -12,6 +12,7 @@ #include <linux/module.h> #include <linux/slab.h> #include <linux/vmalloc.h> +#include <linux/mmiotrace.h> #include <asm/cacheflush.h> #include <asm/e820.h> @@ -122,10 +123,13 @@ static void __iomem *__ioremap_caller(resource_size_t phys_addr, { unsigned long pfn, offset, vaddr; resource_size_t last_addr; + const resource_size_t unaligned_phys_addr = phys_addr; + const unsigned long unaligned_size = size; struct vm_struct *area; unsigned long new_prot_val; pgprot_t prot; int retval; + void __iomem *ret_addr; /* Don't allow wraparound or zero size */ last_addr = phys_addr + size - 1; @@ -233,7 +237,10 @@ static void __iomem *__ioremap_caller(resource_size_t phys_addr, return NULL; } - return (void __iomem *) (vaddr + offset); + ret_addr = (void __iomem *) (vaddr + offset); + mmiotrace_ioremap(unaligned_phys_addr, unaligned_size, ret_addr); + + return ret_addr; } /** @@ -348,6 +355,8 @@ void iounmap(volatile void __iomem *addr) addr = (volatile void __iomem *) (PAGE_MASK & (unsigned long __force)addr); + mmiotrace_iounmap(addr); + /* Use the vm area unlocked, assuming the caller ensures there isn't another iounmap for the same address in parallel. Reuse of the virtual address is prevented by diff --git a/arch/x86/mm/kmmio.c b/arch/x86/mm/kmmio.c new file mode 100644 index 00000000000..93d82038af4 --- /dev/null +++ b/arch/x86/mm/kmmio.c @@ -0,0 +1,510 @@ +/* Support for MMIO probes. + * Benfit many code from kprobes + * (C) 2002 Louis Zhuang <louis.zhuang@intel.com>. + * 2007 Alexander Eichner + * 2008 Pekka Paalanen <pq@iki.fi> + */ + +#include <linux/list.h> +#include <linux/rculist.h> +#include <linux/spinlock.h> +#include <linux/hash.h> +#include <linux/init.h> +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/uaccess.h> +#include <linux/ptrace.h> +#include <linux/preempt.h> +#include <linux/percpu.h> +#include <linux/kdebug.h> +#include <linux/mutex.h> +#include <linux/io.h> +#include <asm/cacheflush.h> +#include <asm/tlbflush.h> +#include <linux/errno.h> +#include <asm/debugreg.h> +#include <linux/mmiotrace.h> + +#define KMMIO_PAGE_HASH_BITS 4 +#define KMMIO_PAGE_TABLE_SIZE (1 << KMMIO_PAGE_HASH_BITS) + +struct kmmio_fault_page { + struct list_head list; + struct kmmio_fault_page *release_next; + unsigned long page; /* location of the fault page */ + + /* + * Number of times this page has been registered as a part + * of a probe. If zero, page is disarmed and this may be freed. + * Used only by writers (RCU). + */ + int count; +}; + +struct kmmio_delayed_release { + struct rcu_head rcu; + struct kmmio_fault_page *release_list; +}; + +struct kmmio_context { + struct kmmio_fault_page *fpage; + struct kmmio_probe *probe; + unsigned long saved_flags; + unsigned long addr; + int active; +}; + +static DEFINE_SPINLOCK(kmmio_lock); + +/* Protected by kmmio_lock */ +unsigned int kmmio_count; + +/* Read-protected by RCU, write-protected by kmmio_lock. */ +static struct list_head kmmio_page_table[KMMIO_PAGE_TABLE_SIZE]; +static LIST_HEAD(kmmio_probes); + +static struct list_head *kmmio_page_list(unsigned long page) +{ + return &kmmio_page_table[hash_long(page, KMMIO_PAGE_HASH_BITS)]; +} + +/* Accessed per-cpu */ +static DEFINE_PER_CPU(struct kmmio_context, kmmio_ctx); + +/* + * this is basically a dynamic stabbing problem: + * Could use the existing prio tree code or + * Possible better implementations: + * The Interval Skip List: A Data Structure for Finding All Intervals That + * Overlap a Point (might be simple) + * Space Efficient Dynamic Stabbing with Fast Queries - Mikkel Thorup + */ +/* Get the kmmio at this addr (if any). You must be holding RCU read lock. */ +static struct kmmio_probe *get_kmmio_probe(unsigned long addr) +{ + struct kmmio_probe *p; + list_for_each_entry_rcu(p, &kmmio_probes, list) { + if (addr >= p->addr && addr <= (p->addr + p->len)) + return p; + } + return NULL; +} + +/* You must be holding RCU read lock. */ +static struct kmmio_fault_page *get_kmmio_fault_page(unsigned long page) +{ + struct list_head *head; + struct kmmio_fault_page *p; + + page &= PAGE_MASK; + head = kmmio_page_list(page); + list_for_each_entry_rcu(p, head, list) { + if (p->page == page) + return p; + } + return NULL; +} + +static void set_page_present(unsigned long addr, bool present, + unsigned int *pglevel) +{ + pteval_t pteval; + pmdval_t pmdval; + unsigned int level; + pmd_t *pmd; + pte_t *pte = lookup_address(addr, &level); + + if (!pte) { + pr_err("kmmio: no pte for page 0x%08lx\n", addr); + return; + } + + if (pglevel) + *pglevel = level; + + switch (level) { + case PG_LEVEL_2M: + pmd = (pmd_t *)pte; + pmdval = pmd_val(*pmd) & ~_PAGE_PRESENT; + if (present) + pmdval |= _PAGE_PRESENT; + set_pmd(pmd, __pmd(pmdval)); + break; + + case PG_LEVEL_4K: + pteval = pte_val(*pte) & ~_PAGE_PRESENT; + if (present) + pteval |= _PAGE_PRESENT; + set_pte_atomic(pte, __pte(pteval)); + break; + + default: + pr_err("kmmio: unexpected page level 0x%x.\n", level); + return; + } + + __flush_tlb_one(addr); +} + +/** Mark the given page as not present. Access to it will trigger a fault. */ +static void arm_kmmio_fault_page(unsigned long page, unsigned int *pglevel) +{ + set_page_present(page & PAGE_MASK, false, pglevel); +} + +/** Mark the given page as present. */ +static void disarm_kmmio_fault_page(unsigned long page, unsigned int *pglevel) +{ + set_page_present(page & PAGE_MASK, true, pglevel); +} + +/* + * This is being called from do_page_fault(). + * + * We may be in an interrupt or a critical section. Also prefecthing may + * trigger a page fault. We may be in the middle of process switch. + * We cannot take any locks, because we could be executing especially + * within a kmmio critical section. + * + * Local interrupts are disabled, so preemption cannot happen. + * Do not enable interrupts, do not sleep, and watch out for other CPUs. + */ +/* + * Interrupts are disabled on entry as trap3 is an interrupt gate + * and they remain disabled thorough out this function. + */ +int kmmio_handler(struct pt_regs *regs, unsigned long addr) +{ + struct kmmio_context *ctx; + struct kmmio_fault_page *faultpage; + int ret = 0; /* default to fault not handled */ + + /* + * Preemption is now disabled to prevent process switch during + * single stepping. We can only handle one active kmmio trace + * per cpu, so ensure that we finish it before something else + * gets to run. We also hold the RCU read lock over single + * stepping to avoid looking up the probe and kmmio_fault_page + * again. + */ + preempt_disable(); + rcu_read_lock(); + + faultpage = get_kmmio_fault_page(addr); + if (!faultpage) { + /* + * Either this page fault is not caused by kmmio, or + * another CPU just pulled the kmmio probe from under + * our feet. The latter case should not be possible. + */ + goto no_kmmio; + } + + ctx = &get_cpu_var(kmmio_ctx); + if (ctx->active) { + disarm_kmmio_fault_page(faultpage->page, NULL); + if (addr == ctx->addr) { + /* + * On SMP we sometimes get recursive probe hits on the + * same address. Context is already saved, fall out. + */ + pr_debug("kmmio: duplicate probe hit on CPU %d, for " + "address 0x%08lx.\n", + smp_processor_id(), addr); + ret = 1; + goto no_kmmio_ctx; + } + /* + * Prevent overwriting already in-flight context. + * This should not happen, let's hope disarming at least + * prevents a panic. + */ + pr_emerg("kmmio: recursive probe hit on CPU %d, " + "for address 0x%08lx. Ignoring.\n", + smp_processor_id(), addr); + pr_emerg("kmmio: previous hit was at 0x%08lx.\n", + ctx->addr); + goto no_kmmio_ctx; + } + ctx->active++; + + ctx->fpage = faultpage; + ctx->probe = get_kmmio_probe(addr); + ctx->saved_flags = (regs->flags & (X86_EFLAGS_TF | X86_EFLAGS_IF)); + ctx->addr = addr; + + if (ctx->probe && ctx->probe->pre_handler) + ctx->probe->pre_handler(ctx->probe, regs, addr); + + /* + * Enable single-stepping and disable interrupts for the faulting + * context. Local interrupts must not get enabled during stepping. + */ + regs->flags |= X86_EFLAGS_TF; + regs->flags &= ~X86_EFLAGS_IF; + + /* Now we set present bit in PTE and single step. */ + disarm_kmmio_fault_page(ctx->fpage->page, NULL); + + /* + * If another cpu accesses the same page while we are stepping, + * the access will not be caught. It will simply succeed and the + * only downside is we lose the event. If this becomes a problem, + * the user should drop to single cpu before tracing. + */ + + put_cpu_var(kmmio_ctx); + return 1; /* fault handled */ + +no_kmmio_ctx: + put_cpu_var(kmmio_ctx); +no_kmmio: + rcu_read_unlock(); + preempt_enable_no_resched(); + return ret; +} + +/* + * Interrupts are disabled on entry as trap1 is an interrupt gate + * and they remain disabled thorough out this function. + * This must always get called as the pair to kmmio_handler(). + */ +static int post_kmmio_handler(unsigned long condition, struct pt_regs *regs) +{ + int ret = 0; + struct kmmio_context *ctx = &get_cpu_var(kmmio_ctx); + + if (!ctx->active) { + pr_debug("kmmio: spurious debug trap on CPU %d.\n", + smp_processor_id()); + goto out; + } + + if (ctx->probe && ctx->probe->post_handler) + ctx->probe->post_handler(ctx->probe, condition, regs); + + arm_kmmio_fault_page(ctx->fpage->page, NULL); + + regs->flags &= ~X86_EFLAGS_TF; + regs->flags |= ctx->saved_flags; + + /* These were acquired in kmmio_handler(). */ + ctx->active--; + BUG_ON(ctx->active); + rcu_read_unlock(); + preempt_enable_no_resched(); + + /* + * if somebody else is singlestepping across a probe point, flags + * will have TF set, in which case, continue the remaining processing + * of do_debug, as if this is not a probe hit. + */ + if (!(regs->flags & X86_EFLAGS_TF)) + ret = 1; +out: + put_cpu_var(kmmio_ctx); + return ret; +} + +/* You must be holding kmmio_lock. */ +static int add_kmmio_fault_page(unsigned long page) +{ + struct kmmio_fault_page *f; + + page &= PAGE_MASK; + f = get_kmmio_fault_page(page); + if (f) { + if (!f->count) + arm_kmmio_fault_page(f->page, NULL); + f->count++; + return 0; + } + + f = kmalloc(sizeof(*f), GFP_ATOMIC); + if (!f) + return -1; + + f->count = 1; + f->page = page; + list_add_rcu(&f->list, kmmio_page_list(f->page)); + + arm_kmmio_fault_page(f->page, NULL); + + return 0; +} + +/* You must be holding kmmio_lock. */ +static void release_kmmio_fault_page(unsigned long page, + struct kmmio_fault_page **release_list) +{ + struct kmmio_fault_page *f; + + page &= PAGE_MASK; + f = get_kmmio_fault_page(page); + if (!f) + return; + + f->count--; + BUG_ON(f->count < 0); + if (!f->count) { + disarm_kmmio_fault_page(f->page, NULL); + f->release_next = *release_list; + *release_list = f; + } +} + +/* + * With page-unaligned ioremaps, one or two armed pages may contain + * addresses from outside the intended mapping. Events for these addresses + * are currently silently dropped. The events may result only from programming + * mistakes by accessing addresses before the beginning or past the end of a + * mapping. + */ +int register_kmmio_probe(struct kmmio_probe *p) +{ + unsigned long flags; + int ret = 0; + unsigned long size = 0; + const unsigned long size_lim = p->len + (p->addr & ~PAGE_MASK); + + spin_lock_irqsave(&kmmio_lock, flags); + if (get_kmmio_probe(p->addr)) { + ret = -EEXIST; + goto out; + } + kmmio_count++; + list_add_rcu(&p->list, &kmmio_probes); + while (size < size_lim) { + if (add_kmmio_fault_page(p->addr + size)) + pr_err("kmmio: Unable to set page fault.\n"); + size += PAGE_SIZE; + } +out: + spin_unlock_irqrestore(&kmmio_lock, flags); + /* + * XXX: What should I do here? + * Here was a call to global_flush_tlb(), but it does not exist + * anymore. It seems it's not needed after all. + */ + return ret; +} +EXPORT_SYMBOL(register_kmmio_probe); + +static void rcu_free_kmmio_fault_pages(struct rcu_head *head) +{ + struct kmmio_delayed_release *dr = container_of( + head, + struct kmmio_delayed_release, + rcu); + struct kmmio_fault_page *p = dr->release_list; + while (p) { + struct kmmio_fault_page *next = p->release_next; + BUG_ON(p->count); + kfree(p); + p = next; + } + kfree(dr); +} + +static void remove_kmmio_fault_pages(struct rcu_head *head) +{ + struct kmmio_delayed_release *dr = container_of( + head, + struct kmmio_delayed_release, + rcu); + struct kmmio_fault_page *p = dr->release_list; + struct kmmio_fault_page **prevp = &dr->release_list; + unsigned long flags; + spin_lock_irqsave(&kmmio_lock, flags); + while (p) { + if (!p->count) + list_del_rcu(&p->list); + else + *prevp = p->release_next; + prevp = &p->release_next; + p = p->release_next; + } + spin_unlock_irqrestore(&kmmio_lock, flags); + /* This is the real RCU destroy call. */ + call_rcu(&dr->rcu, rcu_free_kmmio_fault_pages); +} + +/* + * Remove a kmmio probe. You have to synchronize_rcu() before you can be + * sure that the callbacks will not be called anymore. Only after that + * you may actually release your struct kmmio_probe. + * + * Unregistering a kmmio fault page has three steps: + * 1. release_kmmio_fault_page() + * Disarm the page, wait a grace period to let all faults finish. + * 2. remove_kmmio_fault_pages() + * Remove the pages from kmmio_page_table. + * 3. rcu_free_kmmio_fault_pages() + * Actally free the kmmio_fault_page structs as with RCU. + */ +void unregister_kmmio_probe(struct kmmio_probe *p) +{ + unsigned long flags; + unsigned long size = 0; + const unsigned long size_lim = p->len + (p->addr & ~PAGE_MASK); + struct kmmio_fault_page *release_list = NULL; + struct kmmio_delayed_release *drelease; + + spin_lock_irqsave(&kmmio_lock, flags); + while (size < size_lim) { + release_kmmio_fault_page(p->addr + size, &release_list); + size += PAGE_SIZE; + } + list_del_rcu(&p->list); + kmmio_count--; + spin_unlock_irqrestore(&kmmio_lock, flags); + + drelease = kmalloc(sizeof(*drelease), GFP_ATOMIC); + if (!drelease) { + pr_crit("kmmio: leaking kmmio_fault_page objects.\n"); + return; + } + drelease->release_list = release_list; + + /* + * This is not really RCU here. We have just disarmed a set of + * pages so that they cannot trigger page faults anymore. However, + * we cannot remove the pages from kmmio_page_table, + * because a probe hit might be in flight on another CPU. The + * pages are collected into a list, and they will be removed from + * kmmio_page_table when it is certain that no probe hit related to + * these pages can be in flight. RCU grace period sounds like a + * good choice. + * + * If we removed the pages too early, kmmio page fault handler might + * not find the respective kmmio_fault_page and determine it's not + * a kmmio fault, when it actually is. This would lead to madness. + */ + call_rcu(&drelease->rcu, remove_kmmio_fault_pages); +} +EXPORT_SYMBOL(unregister_kmmio_probe); + +static int kmmio_die_notifier(struct notifier_block *nb, unsigned long val, + void *args) +{ + struct die_args *arg = args; + + if (val == DIE_DEBUG && (arg->err & DR_STEP)) + if (post_kmmio_handler(arg->err, arg->regs) == 1) + return NOTIFY_STOP; + + return NOTIFY_DONE; +} + +static struct notifier_block nb_die = { + .notifier_call = kmmio_die_notifier +}; + +static int __init init_kmmio(void) +{ + int i; + for (i = 0; i < KMMIO_PAGE_TABLE_SIZE; i++) + INIT_LIST_HEAD(&kmmio_page_table[i]); + return register_die_notifier(&nb_die); +} +fs_initcall(init_kmmio); /* should be before device_initcall() */ diff --git a/arch/x86/mm/mmio-mod.c b/arch/x86/mm/mmio-mod.c new file mode 100644 index 00000000000..e7397e108be --- /dev/null +++ b/arch/x86/mm/mmio-mod.c @@ -0,0 +1,515 @@ +/* + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * + * Copyright (C) IBM Corporation, 2005 + * Jeff Muizelaar, 2006, 2007 + * Pekka Paalanen, 2008 <pq@iki.fi> + * + * Derived from the read-mod example from relay-examples by Tom Zanussi. + */ +#define DEBUG 1 + +#include <linux/module.h> +#include <linux/debugfs.h> +#include <linux/uaccess.h> +#include <linux/io.h> +#include <linux/version.h> +#include <linux/kallsyms.h> +#include <asm/pgtable.h> +#include <linux/mmiotrace.h> +#include <asm/e820.h> /* for ISA_START_ADDRESS */ +#include <asm/atomic.h> +#include <linux/percpu.h> +#include <linux/cpu.h> + +#include "pf_in.h" + +#define NAME "mmiotrace: " + +struct trap_reason { + unsigned long addr; + unsigned long ip; + enum reason_type type; + int active_traces; +}; + +struct remap_trace { + struct list_head list; + struct kmmio_probe probe; + resource_size_t phys; + unsigned long id; +}; + +/* Accessed per-cpu. */ +static DEFINE_PER_CPU(struct trap_reason, pf_reason); +static DEFINE_PER_CPU(struct mmiotrace_rw, cpu_trace); + +#if 0 /* XXX: no way gather this info anymore */ +/* Access to this is not per-cpu. */ +static DEFINE_PER_CPU(atomic_t, dropped); +#endif + +static struct dentry *marker_file; + +static DEFINE_MUTEX(mmiotrace_mutex); +static DEFINE_SPINLOCK(trace_lock); +static atomic_t mmiotrace_enabled; +static LIST_HEAD(trace_list); /* struct remap_trace */ + +/* + * Locking in this file: + * - mmiotrace_mutex enforces enable/disable_mmiotrace() critical sections. + * - mmiotrace_enabled may be modified only when holding mmiotrace_mutex + * and trace_lock. + * - Routines depending on is_enabled() must take trace_lock. + * - trace_list users must hold trace_lock. + * - is_enabled() guarantees that mmio_trace_record is allowed. + * - pre/post callbacks assume the effect of is_enabled() being true. + */ + +/* module parameters */ +static unsigned long filter_offset; +static int nommiotrace; +static int trace_pc; + +module_param(filter_offset, ulong, 0); +module_param(nommiotrace, bool, 0); +module_param(trace_pc, bool, 0); + +MODULE_PARM_DESC(filter_offset, "Start address of traced mappings."); +MODULE_PARM_DESC(nommiotrace, "Disable actual MMIO tracing."); +MODULE_PARM_DESC(trace_pc, "Record address of faulting instructions."); + +static bool is_enabled(void) +{ + return atomic_read(&mmiotrace_enabled); +} + +#if 0 /* XXX: needs rewrite */ +/* + * Write callback for the debugfs entry: + * Read a marker and write it to the mmio trace log + */ +static ssize_t write_marker(struct file *file, const char __user *buffer, + size_t count, loff_t *ppos) +{ + char *event = NULL; + struct mm_io_header *headp; + ssize_t len = (count > 65535) ? 65535 : count; + + event = kzalloc(sizeof(*headp) + len, GFP_KERNEL); + if (!event) + return -ENOMEM; + + headp = (struct mm_io_header *)event; + headp->type = MMIO_MAGIC | (MMIO_MARKER << MMIO_OPCODE_SHIFT); + headp->data_len = len; + + if (copy_from_user(event + sizeof(*headp), buffer, len)) { + kfree(event); + return -EFAULT; + } + + spin_lock_irq(&trace_lock); +#if 0 /* XXX: convert this to use tracing */ + if (is_enabled()) + relay_write(chan, event, sizeof(*headp) + len); + else +#endif + len = -EINVAL; + spin_unlock_irq(&trace_lock); + kfree(event); + return len; +} +#endif + +static void print_pte(unsigned long address) +{ + unsigned int level; + pte_t *pte = lookup_address(address, &level); + + if (!pte) { + pr_err(NAME "Error in %s: no pte for page 0x%08lx\n", + __func__, address); + return; + } + + if (level == PG_LEVEL_2M) { + pr_emerg(NAME "4MB pages are not currently supported: " + "0x%08lx\n", address); + BUG(); + } + pr_info(NAME "pte for 0x%lx: 0x%llx 0x%llx\n", address, + (unsigned long long)pte_val(*pte), + (unsigned long long)pte_val(*pte) & _PAGE_PRESENT); +} + +/* + * For some reason the pre/post pairs have been called in an + * unmatched order. Report and die. + */ +static void die_kmmio_nesting_error(struct pt_regs *regs, unsigned long addr) +{ + const struct trap_reason *my_reason = &get_cpu_var(pf_reason); + pr_emerg(NAME "unexpected fault for address: 0x%08lx, " + "last fault for address: 0x%08lx\n", + addr, my_reason->addr); + print_pte(addr); + print_symbol(KERN_EMERG "faulting IP is at %s\n", regs->ip); + print_symbol(KERN_EMERG "last faulting IP was at %s\n", my_reason->ip); +#ifdef __i386__ + pr_emerg("eax: %08lx ebx: %08lx ecx: %08lx edx: %08lx\n", + regs->ax, regs->bx, regs->cx, regs->dx); + pr_emerg("esi: %08lx edi: %08lx ebp: %08lx esp: %08lx\n", + regs->si, regs->di, regs->bp, regs->sp); +#else + pr_emerg("rax: %016lx rcx: %016lx rdx: %016lx\n", + regs->ax, regs->cx, regs->dx); + pr_emerg("rsi: %016lx rdi: %016lx rbp: %016lx rsp: %016lx\n", + regs->si, regs->di, regs->bp, regs->sp); +#endif + put_cpu_var(pf_reason); + BUG(); +} + +static void pre(struct kmmio_probe *p, struct pt_regs *regs, + unsigned long addr) +{ + struct trap_reason *my_reason = &get_cpu_var(pf_reason); + struct mmiotrace_rw *my_trace = &get_cpu_var(cpu_trace); + const unsigned long instptr = instruction_pointer(regs); + const enum reason_type type = get_ins_type(instptr); + struct remap_trace *trace = p->private; + + /* it doesn't make sense to have more than one active trace per cpu */ + if (my_reason->active_traces) + die_kmmio_nesting_error(regs, addr); + else + my_reason->active_traces++; + + my_reason->type = type; + my_reason->addr = addr; + my_reason->ip = instptr; + + my_trace->phys = addr - trace->probe.addr + trace->phys; + my_trace->map_id = trace->id; + + /* + * Only record the program counter when requested. + * It may taint clean-room reverse engineering. + */ + if (trace_pc) + my_trace->pc = instptr; + else + my_trace->pc = 0; + + /* + * XXX: the timestamp recorded will be *after* the tracing has been + * done, not at the time we hit the instruction. SMP implications + * on event ordering? + */ + + switch (type) { + case REG_READ: + my_trace->opcode = MMIO_READ; + my_trace->width = get_ins_mem_width(instptr); + break; + case REG_WRITE: + my_trace->opcode = MMIO_WRITE; + my_trace->width = get_ins_mem_width(instptr); + my_trace->value = get_ins_reg_val(instptr, regs); + break; + case IMM_WRITE: + my_trace->opcode = MMIO_WRITE; + my_trace->width = get_ins_mem_width(instptr); + my_trace->value = get_ins_imm_val(instptr); + break; + default: + { + unsigned char *ip = (unsigned char *)instptr; + my_trace->opcode = MMIO_UNKNOWN_OP; + my_trace->width = 0; + my_trace->value = (*ip) << 16 | *(ip + 1) << 8 | + *(ip + 2); + } + } + put_cpu_var(cpu_trace); + put_cpu_var(pf_reason); +} + +static void post(struct kmmio_probe *p, unsigned long condition, + struct pt_regs *regs) +{ + struct trap_reason *my_reason = &get_cpu_var(pf_reason); + struct mmiotrace_rw *my_trace = &get_cpu_var(cpu_trace); + + /* this should always return the active_trace count to 0 */ + my_reason->active_traces--; + if (my_reason->active_traces) { + pr_emerg(NAME "unexpected post handler"); + BUG(); + } + + switch (my_reason->type) { + case REG_READ: + my_trace->value = get_ins_reg_val(my_reason->ip, regs); + break; + default: + break; + } + + mmio_trace_rw(my_trace); + put_cpu_var(cpu_trace); + put_cpu_var(pf_reason); +} + +static void ioremap_trace_core(resource_size_t offset, unsigned long size, + void __iomem *addr) +{ + static atomic_t next_id; + struct remap_trace *trace = kmalloc(sizeof(*trace), GFP_KERNEL); + /* These are page-unaligned. */ + struct mmiotrace_map map = { + .phys = offset, + .virt = (unsigned long)addr, + .len = size, + .opcode = MMIO_PROBE + }; + + if (!trace) { + pr_err(NAME "kmalloc failed in ioremap\n"); + return; + } + + *trace = (struct remap_trace) { + .probe = { + .addr = (unsigned long)addr, + .len = size, + .pre_handler = pre, + .post_handler = post, + .private = trace + }, + .phys = offset, + .id = atomic_inc_return(&next_id) + }; + map.map_id = trace->id; + + spin_lock_irq(&trace_lock); + if (!is_enabled()) + goto not_enabled; + + mmio_trace_mapping(&map); + list_add_tail(&trace->list, &trace_list); + if (!nommiotrace) + register_kmmio_probe(&trace->probe); + +not_enabled: + spin_unlock_irq(&trace_lock); +} + +void mmiotrace_ioremap(resource_size_t offset, unsigned long size, + void __iomem *addr) +{ + if (!is_enabled()) /* recheck and proper locking in *_core() */ + return; + + pr_debug(NAME "ioremap_*(0x%llx, 0x%lx) = %p\n", + (unsigned long long)offset, size, addr); + if ((filter_offset) && (offset != filter_offset)) + return; + ioremap_trace_core(offset, size, addr); +} + +static void iounmap_trace_core(volatile void __iomem *addr) +{ + struct mmiotrace_map map = { + .phys = 0, + .virt = (unsigned long)addr, + .len = 0, + .opcode = MMIO_UNPROBE + }; + struct remap_trace *trace; + struct remap_trace *tmp; + struct remap_trace *found_trace = NULL; + + pr_debug(NAME "Unmapping %p.\n", addr); + + spin_lock_irq(&trace_lock); + if (!is_enabled()) + goto not_enabled; + + list_for_each_entry_safe(trace, tmp, &trace_list, list) { + if ((unsigned long)addr == trace->probe.addr) { + if (!nommiotrace) + unregister_kmmio_probe(&trace->probe); + list_del(&trace->list); + found_trace = trace; + break; + } + } + map.map_id = (found_trace) ? found_trace->id : -1; + mmio_trace_mapping(&map); + +not_enabled: + spin_unlock_irq(&trace_lock); + if (found_trace) { + synchronize_rcu(); /* unregister_kmmio_probe() requirement */ + kfree(found_trace); + } +} + +void mmiotrace_iounmap(volatile void __iomem *addr) +{ + might_sleep(); + if (is_enabled()) /* recheck and proper locking in *_core() */ + iounmap_trace_core(addr); +} + +static void clear_trace_list(void) +{ + struct remap_trace *trace; + struct remap_trace *tmp; + + /* + * No locking required, because the caller ensures we are in a + * critical section via mutex, and is_enabled() is false, + * i.e. nothing can traverse or modify this list. + * Caller also ensures is_enabled() cannot change. + */ + list_for_each_entry(trace, &trace_list, list) { + pr_notice(NAME "purging non-iounmapped " + "trace @0x%08lx, size 0x%lx.\n", + trace->probe.addr, trace->probe.len); + if (!nommiotrace) + unregister_kmmio_probe(&trace->probe); + } + synchronize_rcu(); /* unregister_kmmio_probe() requirement */ + + list_for_each_entry_safe(trace, tmp, &trace_list, list) { + list_del(&trace->list); + kfree(trace); + } +} + +#ifdef CONFIG_HOTPLUG_CPU +static cpumask_t downed_cpus; + +static void enter_uniprocessor(void) +{ + int cpu; + int err; + + get_online_cpus(); + downed_cpus = cpu_online_map; + cpu_clear(first_cpu(cpu_online_map), downed_cpus); + if (num_online_cpus() > 1) + pr_notice(NAME "Disabling non-boot CPUs...\n"); + put_online_cpus(); + + for_each_cpu_mask(cpu, downed_cpus) { + err = cpu_down(cpu); + if (!err) + pr_info(NAME "CPU%d is down.\n", cpu); + else + pr_err(NAME "Error taking CPU%d down: %d\n", cpu, err); + } + if (num_online_cpus() > 1) + pr_warning(NAME "multiple CPUs still online, " + "may miss events.\n"); +} + +static void leave_uniprocessor(void) +{ + int cpu; + int err; + + if (cpus_weight(downed_cpus) == 0) + return; + pr_notice(NAME "Re-enabling CPUs...\n"); + for_each_cpu_mask(cpu, downed_cpus) { + err = cpu_up(cpu); + if (!err) + pr_info(NAME "enabled CPU%d.\n", cpu); + else + pr_err(NAME "cannot re-enable CPU%d: %d\n", cpu, err); + } +} + +#else /* !CONFIG_HOTPLUG_CPU */ +static void enter_uniprocessor(void) +{ + if (num_online_cpus() > 1) + pr_warning(NAME "multiple CPUs are online, may miss events. " + "Suggest booting with maxcpus=1 kernel argument.\n"); +} + +static void leave_uniprocessor(void) +{ +} +#endif + +#if 0 /* XXX: out of order */ +static struct file_operations fops_marker = { + .owner = THIS_MODULE, + .write = write_marker +}; +#endif + +void enable_mmiotrace(void) +{ + mutex_lock(&mmiotrace_mutex); + if (is_enabled()) + goto out; + +#if 0 /* XXX: tracing does not support text entries */ + marker_file = debugfs_create_file("marker", 0660, dir, NULL, + &fops_marker); + if (!marker_file) + pr_err(NAME "marker file creation failed.\n"); +#endif + + if (nommiotrace) + pr_info(NAME "MMIO tracing disabled.\n"); + enter_uniprocessor(); + spin_lock_irq(&trace_lock); + atomic_inc(&mmiotrace_enabled); + spin_unlock_irq(&trace_lock); + pr_info(NAME "enabled.\n"); +out: + mutex_unlock(&mmiotrace_mutex); +} + +void disable_mmiotrace(void) +{ + mutex_lock(&mmiotrace_mutex); + if (!is_enabled()) + goto out; + + spin_lock_irq(&trace_lock); + atomic_dec(&mmiotrace_enabled); + BUG_ON(is_enabled()); + spin_unlock_irq(&trace_lock); + + clear_trace_list(); /* guarantees: no more kmmio callbacks */ + leave_uniprocessor(); + if (marker_file) { + debugfs_remove(marker_file); + marker_file = NULL; + } + + pr_info(NAME "disabled.\n"); +out: + mutex_unlock(&mmiotrace_mutex); +} diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c index fb6f2ab40dd..47f4e2e4a09 100644 --- a/arch/x86/mm/pageattr.c +++ b/arch/x86/mm/pageattr.c @@ -262,6 +262,7 @@ pte_t *lookup_address(unsigned long address, unsigned int *level) return pte_offset_kernel(pmd, address); } +EXPORT_SYMBOL_GPL(lookup_address); /* * Set the new pmd in all the pgds we know about: diff --git a/arch/x86/mm/pf_in.c b/arch/x86/mm/pf_in.c new file mode 100644 index 00000000000..efa1911e20c --- /dev/null +++ b/arch/x86/mm/pf_in.c @@ -0,0 +1,489 @@ +/* + * Fault Injection Test harness (FI) + * Copyright (C) Intel Crop. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, + * USA. + * + */ + +/* Id: pf_in.c,v 1.1.1.1 2002/11/12 05:56:32 brlock Exp + * Copyright by Intel Crop., 2002 + * Louis Zhuang (louis.zhuang@intel.com) + * + * Bjorn Steinbrink (B.Steinbrink@gmx.de), 2007 + */ + +#include <linux/module.h> +#include <linux/ptrace.h> /* struct pt_regs */ +#include "pf_in.h" + +#ifdef __i386__ +/* IA32 Manual 3, 2-1 */ +static unsigned char prefix_codes[] = { + 0xF0, 0xF2, 0xF3, 0x2E, 0x36, 0x3E, 0x26, 0x64, + 0x65, 0x2E, 0x3E, 0x66, 0x67 +}; +/* IA32 Manual 3, 3-432*/ +static unsigned int reg_rop[] = { + 0x8A, 0x8B, 0xB60F, 0xB70F, 0xBE0F, 0xBF0F +}; +static unsigned int reg_wop[] = { 0x88, 0x89 }; +static unsigned int imm_wop[] = { 0xC6, 0xC7 }; +/* IA32 Manual 3, 3-432*/ +static unsigned int rw8[] = { 0x88, 0x8A, 0xC6 }; +static unsigned int rw32[] = { + 0x89, 0x8B, 0xC7, 0xB60F, 0xB70F, 0xBE0F, 0xBF0F +}; +static unsigned int mw8[] = { 0x88, 0x8A, 0xC6, 0xB60F, 0xBE0F }; +static unsigned int mw16[] = { 0xB70F, 0xBF0F }; +static unsigned int mw32[] = { 0x89, 0x8B, 0xC7 }; +static unsigned int mw64[] = {}; +#else /* not __i386__ */ +static unsigned char prefix_codes[] = { + 0x66, 0x67, 0x2E, 0x3E, 0x26, 0x64, 0x65, 0x36, + 0xF0, 0xF3, 0xF2, + /* REX Prefixes */ + 0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, + 0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f +}; +/* AMD64 Manual 3, Appendix A*/ +static unsigned int reg_rop[] = { + 0x8A, 0x8B, 0xB60F, 0xB70F, 0xBE0F, 0xBF0F +}; +static unsigned int reg_wop[] = { 0x88, 0x89 }; +static unsigned int imm_wop[] = { 0xC6, 0xC7 }; +static unsigned int rw8[] = { 0xC6, 0x88, 0x8A }; +static unsigned int rw32[] = { + 0xC7, 0x89, 0x8B, 0xB60F, 0xB70F, 0xBE0F, 0xBF0F +}; +/* 8 bit only */ +static unsigned int mw8[] = { 0xC6, 0x88, 0x8A, 0xB60F, 0xBE0F }; +/* 16 bit only */ +static unsigned int mw16[] = { 0xB70F, 0xBF0F }; +/* 16 or 32 bit */ +static unsigned int mw32[] = { 0xC7 }; +/* 16, 32 or 64 bit */ +static unsigned int mw64[] = { 0x89, 0x8B }; +#endif /* not __i386__ */ + +static int skip_prefix(unsigned char *addr, int *shorted, int *enlarged, + int *rexr) +{ + int i; + unsigned char *p = addr; + *shorted = 0; + *enlarged = 0; + *rexr = 0; + +restart: + for (i = 0; i < ARRAY_SIZE(prefix_codes); i++) { + if (*p == prefix_codes[i]) { + if (*p == 0x66) + *shorted = 1; +#ifdef __amd64__ + if ((*p & 0xf8) == 0x48) + *enlarged = 1; + if ((*p & 0xf4) == 0x44) + *rexr = 1; +#endif + p++; + goto restart; + } + } + + return (p - addr); +} + +static int get_opcode(unsigned char *addr, unsigned int *opcode) +{ + int len; + + if (*addr == 0x0F) { + /* 0x0F is extension instruction */ + *opcode = *(unsigned short *)addr; + len = 2; + } else { + *opcode = *addr; + len = 1; + } + + return len; +} + +#define CHECK_OP_TYPE(opcode, array, type) \ + for (i = 0; i < ARRAY_SIZE(array); i++) { \ + if (array[i] == opcode) { \ + rv = type; \ + goto exit; \ + } \ + } + +enum reason_type get_ins_type(unsigned long ins_addr) +{ + unsigned int opcode; + unsigned char *p; + int shorted, enlarged, rexr; + int i; + enum reason_type rv = OTHERS; + + p = (unsigned char *)ins_addr; + p += skip_prefix(p, &shorted, &enlarged, &rexr); + p += get_opcode(p, &opcode); + + CHECK_OP_TYPE(opcode, reg_rop, REG_READ); + CHECK_OP_TYPE(opcode, reg_wop, REG_WRITE); + CHECK_OP_TYPE(opcode, imm_wop, IMM_WRITE); + +exit: + return rv; +} +#undef CHECK_OP_TYPE + +static unsigned int get_ins_reg_width(unsigned long ins_addr) +{ + unsigned int opcode; + unsigned char *p; + int i, shorted, enlarged, rexr; + + p = (unsigned char *)ins_addr; + p += skip_prefix(p, &shorted, &enlarged, &rexr); + p += get_opcode(p, &opcode); + + for (i = 0; i < ARRAY_SIZE(rw8); i++) + if (rw8[i] == opcode) + return 1; + + for (i = 0; i < ARRAY_SIZE(rw32); i++) + if (rw32[i] == opcode) + return (shorted ? 2 : (enlarged ? 8 : 4)); + + printk(KERN_ERR "mmiotrace: Unknown opcode 0x%02x\n", opcode); + return 0; +} + +unsigned int get_ins_mem_width(unsigned long ins_addr) +{ + unsigned int opcode; + unsigned char *p; + int i, shorted, enlarged, rexr; + + p = (unsigned char *)ins_addr; + p += skip_prefix(p, &shorted, &enlarged, &rexr); + p += get_opcode(p, &opcode); + + for (i = 0; i < ARRAY_SIZE(mw8); i++) + if (mw8[i] == opcode) + return 1; + + for (i = 0; i < ARRAY_SIZE(mw16); i++) + if (mw16[i] == opcode) + return 2; + + for (i = 0; i < ARRAY_SIZE(mw32); i++) + if (mw32[i] == opcode) + return shorted ? 2 : 4; + + for (i = 0; i < ARRAY_SIZE(mw64); i++) + if (mw64[i] == opcode) + return shorted ? 2 : (enlarged ? 8 : 4); + + printk(KERN_ERR "mmiotrace: Unknown opcode 0x%02x\n", opcode); + return 0; +} + +/* + * Define register ident in mod/rm byte. + * Note: these are NOT the same as in ptrace-abi.h. + */ +enum { + arg_AL = 0, + arg_CL = 1, + arg_DL = 2, + arg_BL = 3, + arg_AH = 4, + arg_CH = 5, + arg_DH = 6, + arg_BH = 7, + + arg_AX = 0, + arg_CX = 1, + arg_DX = 2, + arg_BX = 3, + arg_SP = 4, + arg_BP = 5, + arg_SI = 6, + arg_DI = 7, +#ifdef __amd64__ + arg_R8 = 8, + arg_R9 = 9, + arg_R10 = 10, + arg_R11 = 11, + arg_R12 = 12, + arg_R13 = 13, + arg_R14 = 14, + arg_R15 = 15 +#endif +}; + +static unsigned char *get_reg_w8(int no, struct pt_regs *regs) +{ + unsigned char *rv = NULL; + + switch (no) { + case arg_AL: + rv = (unsigned char *)®s->ax; + break; + case arg_BL: + rv = (unsigned char *)®s->bx; + break; + case arg_CL: + rv = (unsigned char *)®s->cx; + break; + case arg_DL: + rv = (unsigned char *)®s->dx; + break; + case arg_AH: + rv = 1 + (unsigned char *)®s->ax; + break; + case arg_BH: + rv = 1 + (unsigned char *)®s->bx; + break; + case arg_CH: + rv = 1 + (unsigned char *)®s->cx; + break; + case arg_DH: + rv = 1 + (unsigned char *)®s->dx; + break; +#ifdef __amd64__ + case arg_R8: + rv = (unsigned char *)®s->r8; + break; + case arg_R9: + rv = (unsigned char *)®s->r9; + break; + case arg_R10: + rv = (unsigned char *)®s->r10; + break; + case arg_R11: + rv = (unsigned char *)®s->r11; + break; + case arg_R12: + rv = (unsigned char *)®s->r12; + break; + case arg_R13: + rv = (unsigned char *)®s->r13; + break; + case arg_R14: + rv = (unsigned char *)®s->r14; + break; + case arg_R15: + rv = (unsigned char *)®s->r15; + break; +#endif + default: + printk(KERN_ERR "mmiotrace: Error reg no# %d\n", no); + break; + } + return rv; +} + +static unsigned long *get_reg_w32(int no, struct pt_regs *regs) +{ + unsigned long *rv = NULL; + + switch (no) { + case arg_AX: + rv = ®s->ax; + break; + case arg_BX: + rv = ®s->bx; + break; + case arg_CX: + rv = ®s->cx; + break; + case arg_DX: + rv = ®s->dx; + break; + case arg_SP: + rv = ®s->sp; + break; + case arg_BP: + rv = ®s->bp; + break; + case arg_SI: + rv = ®s->si; + break; + case arg_DI: + rv = ®s->di; + break; +#ifdef __amd64__ + case arg_R8: + rv = ®s->r8; + break; + case arg_R9: + rv = ®s->r9; + break; + case arg_R10: + rv = ®s->r10; + break; + case arg_R11: + rv = ®s->r11; + break; + case arg_R12: + rv = ®s->r12; + break; + case arg_R13: + rv = ®s->r13; + break; + case arg_R14: + rv = ®s->r14; + break; + case arg_R15: + rv = ®s->r15; + break; +#endif + default: + printk(KERN_ERR "mmiotrace: Error reg no# %d\n", no); + } + + return rv; +} + +unsigned long get_ins_reg_val(unsigned long ins_addr, struct pt_regs *regs) +{ + unsigned int opcode; + unsigned char mod_rm; + int reg; + unsigned char *p; + int i, shorted, enlarged, rexr; + unsigned long rv; + + p = (unsigned char *)ins_addr; + p += skip_prefix(p, &shorted, &enlarged, &rexr); + p += get_opcode(p, &opcode); + for (i = 0; i < ARRAY_SIZE(reg_rop); i++) + if (reg_rop[i] == opcode) { + rv = REG_READ; + goto do_work; + } + + for (i = 0; i < ARRAY_SIZE(reg_wop); i++) + if (reg_wop[i] == opcode) { + rv = REG_WRITE; + goto do_work; + } + + printk(KERN_ERR "mmiotrace: Not a register instruction, opcode " + "0x%02x\n", opcode); + goto err; + +do_work: + mod_rm = *p; + reg = ((mod_rm >> 3) & 0x7) | (rexr << 3); + switch (get_ins_reg_width(ins_addr)) { + case 1: + return *get_reg_w8(reg, regs); + + case 2: + return *(unsigned short *)get_reg_w32(reg, regs); + + case 4: + return *(unsigned int *)get_reg_w32(reg, regs); + +#ifdef __amd64__ + case 8: + return *(unsigned long *)get_reg_w32(reg, regs); +#endif + + default: + printk(KERN_ERR "mmiotrace: Error width# %d\n", reg); + } + +err: + return 0; +} + +unsigned long get_ins_imm_val(unsigned long ins_addr) +{ + unsigned int opcode; + unsigned char mod_rm; + unsigned char mod; + unsigned char *p; + int i, shorted, enlarged, rexr; + unsigned long rv; + + p = (unsigned char *)ins_addr; + p += skip_prefix(p, &shorted, &enlarged, &rexr); + p += get_opcode(p, &opcode); + for (i = 0; i < ARRAY_SIZE(imm_wop); i++) + if (imm_wop[i] == opcode) { + rv = IMM_WRITE; + goto do_work; + } + + printk(KERN_ERR "mmiotrace: Not an immediate instruction, opcode " + "0x%02x\n", opcode); + goto err; + +do_work: + mod_rm = *p; + mod = mod_rm >> 6; + p++; + switch (mod) { + case 0: + /* if r/m is 5 we have a 32 disp (IA32 Manual 3, Table 2-2) */ + /* AMD64: XXX Check for address size prefix? */ + if ((mod_rm & 0x7) == 0x5) + p += 4; + break; + + case 1: + p += 1; + break; + + case 2: + p += 4; + break; + + case 3: + default: + printk(KERN_ERR "mmiotrace: not a memory access instruction " + "at 0x%lx, rm_mod=0x%02x\n", + ins_addr, mod_rm); + } + + switch (get_ins_reg_width(ins_addr)) { + case 1: + return *(unsigned char *)p; + + case 2: + return *(unsigned short *)p; + + case 4: + return *(unsigned int *)p; + +#ifdef __amd64__ + case 8: + return *(unsigned long *)p; +#endif + + default: + printk(KERN_ERR "mmiotrace: Error: width.\n"); + } + +err: + return 0; +} diff --git a/arch/x86/mm/pf_in.h b/arch/x86/mm/pf_in.h new file mode 100644 index 00000000000..e05341a51a2 --- /dev/null +++ b/arch/x86/mm/pf_in.h @@ -0,0 +1,39 @@ +/* + * Fault Injection Test harness (FI) + * Copyright (C) Intel Crop. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, + * USA. + * + */ + +#ifndef __PF_H_ +#define __PF_H_ + +enum reason_type { + NOT_ME, /* page fault is not in regions */ + NOTHING, /* access others point in regions */ + REG_READ, /* read from addr to reg */ + REG_WRITE, /* write from reg to addr */ + IMM_WRITE, /* write from imm to addr */ + OTHERS /* Other instructions can not intercept */ +}; + +enum reason_type get_ins_type(unsigned long ins_addr); +unsigned int get_ins_mem_width(unsigned long ins_addr); +unsigned long get_ins_reg_val(unsigned long ins_addr, struct pt_regs *regs); +unsigned long get_ins_imm_val(unsigned long ins_addr); + +#endif /* __PF_H_ */ diff --git a/arch/x86/mm/testmmiotrace.c b/arch/x86/mm/testmmiotrace.c new file mode 100644 index 00000000000..d877c5b423e --- /dev/null +++ b/arch/x86/mm/testmmiotrace.c @@ -0,0 +1,71 @@ +/* + * Written by Pekka Paalanen, 2008 <pq@iki.fi> + */ +#include <linux/module.h> +#include <linux/io.h> + +#define MODULE_NAME "testmmiotrace" + +static unsigned long mmio_address; +module_param(mmio_address, ulong, 0); +MODULE_PARM_DESC(mmio_address, "Start address of the mapping of 16 kB."); + +static void do_write_test(void __iomem *p) +{ + unsigned int i; + for (i = 0; i < 256; i++) + iowrite8(i, p + i); + for (i = 1024; i < (5 * 1024); i += 2) + iowrite16(i * 12 + 7, p + i); + for (i = (5 * 1024); i < (16 * 1024); i += 4) + iowrite32(i * 212371 + 13, p + i); +} + +static void do_read_test(void __iomem *p) +{ + unsigned int i; + for (i = 0; i < 256; i++) + ioread8(p + i); + for (i = 1024; i < (5 * 1024); i += 2) + ioread16(p + i); + for (i = (5 * 1024); i < (16 * 1024); i += 4) + ioread32(p + i); +} + +static void do_test(void) +{ + void __iomem *p = ioremap_nocache(mmio_address, 0x4000); + if (!p) { + pr_err(MODULE_NAME ": could not ioremap, aborting.\n"); + return; + } + do_write_test(p); + do_read_test(p); + iounmap(p); +} + +static int __init init(void) +{ + if (mmio_address == 0) { + pr_err(MODULE_NAME ": you have to use the module argument " + "mmio_address.\n"); + pr_err(MODULE_NAME ": DO NOT LOAD THIS MODULE UNLESS" + " YOU REALLY KNOW WHAT YOU ARE DOING!\n"); + return -ENXIO; + } + + pr_warning(MODULE_NAME ": WARNING: mapping 16 kB @ 0x%08lx " + "in PCI address space, and writing " + "rubbish in there.\n", mmio_address); + do_test(); + return 0; +} + +static void __exit cleanup(void) +{ + pr_debug(MODULE_NAME ": unloaded.\n"); +} + +module_init(init); +module_exit(cleanup); +MODULE_LICENSE("GPL"); diff --git a/arch/x86/vdso/vclock_gettime.c b/arch/x86/vdso/vclock_gettime.c index efa2ba7c600..1ef0f90813d 100644 --- a/arch/x86/vdso/vclock_gettime.c +++ b/arch/x86/vdso/vclock_gettime.c @@ -23,7 +23,7 @@ #define gtod vdso_vsyscall_gtod_data -static long vdso_fallback_gettime(long clock, struct timespec *ts) +notrace static long vdso_fallback_gettime(long clock, struct timespec *ts) { long ret; asm("syscall" : "=a" (ret) : @@ -31,7 +31,7 @@ static long vdso_fallback_gettime(long clock, struct timespec *ts) return ret; } -static inline long vgetns(void) +notrace static inline long vgetns(void) { long v; cycles_t (*vread)(void); @@ -40,7 +40,7 @@ static inline long vgetns(void) return (v * gtod->clock.mult) >> gtod->clock.shift; } -static noinline int do_realtime(struct timespec *ts) +notrace static noinline int do_realtime(struct timespec *ts) { unsigned long seq, ns; do { @@ -54,7 +54,8 @@ static noinline int do_realtime(struct timespec *ts) } /* Copy of the version in kernel/time.c which we cannot directly access */ -static void vset_normalized_timespec(struct timespec *ts, long sec, long nsec) +notrace static void +vset_normalized_timespec(struct timespec *ts, long sec, long nsec) { while (nsec >= NSEC_PER_SEC) { nsec -= NSEC_PER_SEC; @@ -68,7 +69,7 @@ static void vset_normalized_timespec(struct timespec *ts, long sec, long nsec) ts->tv_nsec = nsec; } -static noinline int do_monotonic(struct timespec *ts) +notrace static noinline int do_monotonic(struct timespec *ts) { unsigned long seq, ns, secs; do { @@ -82,7 +83,7 @@ static noinline int do_monotonic(struct timespec *ts) return 0; } -int __vdso_clock_gettime(clockid_t clock, struct timespec *ts) +notrace int __vdso_clock_gettime(clockid_t clock, struct timespec *ts) { if (likely(gtod->sysctl_enabled && gtod->clock.vread)) switch (clock) { @@ -96,7 +97,7 @@ int __vdso_clock_gettime(clockid_t clock, struct timespec *ts) int clock_gettime(clockid_t, struct timespec *) __attribute__((weak, alias("__vdso_clock_gettime"))); -int __vdso_gettimeofday(struct timeval *tv, struct timezone *tz) +notrace int __vdso_gettimeofday(struct timeval *tv, struct timezone *tz) { long ret; if (likely(gtod->sysctl_enabled && gtod->clock.vread)) { diff --git a/arch/x86/vdso/vgetcpu.c b/arch/x86/vdso/vgetcpu.c index c8097f17f8a..9fbc6b20026 100644 --- a/arch/x86/vdso/vgetcpu.c +++ b/arch/x86/vdso/vgetcpu.c @@ -13,7 +13,8 @@ #include <asm/vgtod.h> #include "vextern.h" -long __vdso_getcpu(unsigned *cpu, unsigned *node, struct getcpu_cache *unused) +notrace long +__vdso_getcpu(unsigned *cpu, unsigned *node, struct getcpu_cache *unused) { unsigned int p; |