2021-12-06 18:20:32 +00:00
|
|
|
// SPDX-License-Identifier: GPL-2.0-only
|
|
|
|
#include <linux/module.h>
|
|
|
|
#include <linux/kthread.h>
|
|
|
|
#include <linux/ftrace.h>
|
2024-10-30 07:08:49 +00:00
|
|
|
#if !defined(CONFIG_ARM64) && !defined(CONFIG_PPC32)
|
2021-12-06 18:20:32 +00:00
|
|
|
#include <asm/asm-offsets.h>
|
2023-04-27 14:07:00 +00:00
|
|
|
#endif
|
2021-12-06 18:20:32 +00:00
|
|
|
|
2021-12-19 13:53:17 +00:00
|
|
|
extern void my_direct_func1(unsigned long ip);
|
|
|
|
extern void my_direct_func2(unsigned long ip);
|
|
|
|
|
2021-12-06 18:20:32 +00:00
|
|
|
void my_direct_func1(unsigned long ip)
|
|
|
|
{
|
|
|
|
trace_printk("my direct func1 ip %lx\n", ip);
|
|
|
|
}
|
|
|
|
|
|
|
|
void my_direct_func2(unsigned long ip)
|
|
|
|
{
|
|
|
|
trace_printk("my direct func2 ip %lx\n", ip);
|
|
|
|
}
|
|
|
|
|
|
|
|
extern void my_tramp1(void *);
|
|
|
|
extern void my_tramp2(void *);
|
|
|
|
|
2023-11-30 12:15:31 +00:00
|
|
|
#ifdef CONFIG_RISCV
|
|
|
|
#include <asm/asm.h>
|
|
|
|
|
|
|
|
asm (
|
|
|
|
" .pushsection .text, \"ax\", @progbits\n"
|
|
|
|
" .type my_tramp1, @function\n"
|
|
|
|
" .globl my_tramp1\n"
|
|
|
|
" my_tramp1:\n"
|
|
|
|
" addi sp,sp,-3*"SZREG"\n"
|
|
|
|
" "REG_S" a0,0*"SZREG"(sp)\n"
|
|
|
|
" "REG_S" t0,1*"SZREG"(sp)\n"
|
|
|
|
" "REG_S" ra,2*"SZREG"(sp)\n"
|
|
|
|
" mv a0,t0\n"
|
|
|
|
" call my_direct_func1\n"
|
|
|
|
" "REG_L" a0,0*"SZREG"(sp)\n"
|
|
|
|
" "REG_L" t0,1*"SZREG"(sp)\n"
|
|
|
|
" "REG_L" ra,2*"SZREG"(sp)\n"
|
|
|
|
" addi sp,sp,3*"SZREG"\n"
|
|
|
|
" jr t0\n"
|
|
|
|
" .size my_tramp1, .-my_tramp1\n"
|
|
|
|
|
|
|
|
" .type my_tramp2, @function\n"
|
|
|
|
" .globl my_tramp2\n"
|
|
|
|
" my_tramp2:\n"
|
|
|
|
" addi sp,sp,-3*"SZREG"\n"
|
|
|
|
" "REG_S" a0,0*"SZREG"(sp)\n"
|
|
|
|
" "REG_S" t0,1*"SZREG"(sp)\n"
|
|
|
|
" "REG_S" ra,2*"SZREG"(sp)\n"
|
|
|
|
" mv a0,t0\n"
|
|
|
|
" call my_direct_func2\n"
|
|
|
|
" "REG_L" a0,0*"SZREG"(sp)\n"
|
|
|
|
" "REG_L" t0,1*"SZREG"(sp)\n"
|
|
|
|
" "REG_L" ra,2*"SZREG"(sp)\n"
|
|
|
|
" addi sp,sp,3*"SZREG"\n"
|
|
|
|
" jr t0\n"
|
|
|
|
" .size my_tramp2, .-my_tramp2\n"
|
|
|
|
" .popsection\n"
|
|
|
|
);
|
|
|
|
|
|
|
|
#endif /* CONFIG_RISCV */
|
|
|
|
|
2021-12-06 18:20:32 +00:00
|
|
|
#ifdef CONFIG_X86_64
|
|
|
|
|
2022-03-08 15:30:34 +00:00
|
|
|
#include <asm/ibt.h>
|
2023-01-30 08:59:54 +00:00
|
|
|
#include <asm/nospec-branch.h>
|
2022-03-08 15:30:34 +00:00
|
|
|
|
2021-12-06 18:20:32 +00:00
|
|
|
asm (
|
|
|
|
" .pushsection .text, \"ax\", @progbits\n"
|
|
|
|
" .type my_tramp1, @function\n"
|
|
|
|
" .globl my_tramp1\n"
|
|
|
|
" my_tramp1:"
|
2022-03-08 15:30:34 +00:00
|
|
|
ASM_ENDBR
|
2021-12-06 18:20:32 +00:00
|
|
|
" pushq %rbp\n"
|
|
|
|
" movq %rsp, %rbp\n"
|
2022-09-15 11:11:37 +00:00
|
|
|
CALL_DEPTH_ACCOUNT
|
2021-12-06 18:20:32 +00:00
|
|
|
" pushq %rdi\n"
|
|
|
|
" movq 8(%rbp), %rdi\n"
|
|
|
|
" call my_direct_func1\n"
|
|
|
|
" popq %rdi\n"
|
|
|
|
" leave\n"
|
2022-03-08 15:30:34 +00:00
|
|
|
ASM_RET
|
2021-12-06 18:20:32 +00:00
|
|
|
" .size my_tramp1, .-my_tramp1\n"
|
2022-03-08 15:30:34 +00:00
|
|
|
|
2021-12-06 18:20:32 +00:00
|
|
|
" .type my_tramp2, @function\n"
|
|
|
|
" .globl my_tramp2\n"
|
|
|
|
" my_tramp2:"
|
2022-03-08 15:30:34 +00:00
|
|
|
ASM_ENDBR
|
2021-12-06 18:20:32 +00:00
|
|
|
" pushq %rbp\n"
|
|
|
|
" movq %rsp, %rbp\n"
|
2022-09-15 11:11:37 +00:00
|
|
|
CALL_DEPTH_ACCOUNT
|
2021-12-06 18:20:32 +00:00
|
|
|
" pushq %rdi\n"
|
|
|
|
" movq 8(%rbp), %rdi\n"
|
|
|
|
" call my_direct_func2\n"
|
|
|
|
" popq %rdi\n"
|
|
|
|
" leave\n"
|
2022-03-08 15:30:34 +00:00
|
|
|
ASM_RET
|
2021-12-06 18:20:32 +00:00
|
|
|
" .size my_tramp2, .-my_tramp2\n"
|
|
|
|
" .popsection\n"
|
|
|
|
);
|
|
|
|
|
|
|
|
#endif /* CONFIG_X86_64 */
|
|
|
|
|
|
|
|
#ifdef CONFIG_S390
|
|
|
|
|
|
|
|
asm (
|
|
|
|
" .pushsection .text, \"ax\", @progbits\n"
|
|
|
|
" .type my_tramp1, @function\n"
|
|
|
|
" .globl my_tramp1\n"
|
|
|
|
" my_tramp1:"
|
|
|
|
" lgr %r1,%r15\n"
|
|
|
|
" stmg %r0,%r5,"__stringify(__SF_GPRS)"(%r15)\n"
|
|
|
|
" stg %r14,"__stringify(__SF_GPRS+8*8)"(%r15)\n"
|
|
|
|
" aghi %r15,"__stringify(-STACK_FRAME_OVERHEAD)"\n"
|
|
|
|
" stg %r1,"__stringify(__SF_BACKCHAIN)"(%r15)\n"
|
|
|
|
" lgr %r2,%r0\n"
|
|
|
|
" brasl %r14,my_direct_func1\n"
|
|
|
|
" aghi %r15,"__stringify(STACK_FRAME_OVERHEAD)"\n"
|
|
|
|
" lmg %r0,%r5,"__stringify(__SF_GPRS)"(%r15)\n"
|
|
|
|
" lg %r14,"__stringify(__SF_GPRS+8*8)"(%r15)\n"
|
|
|
|
" lgr %r1,%r0\n"
|
|
|
|
" br %r1\n"
|
|
|
|
" .size my_tramp1, .-my_tramp1\n"
|
|
|
|
"\n"
|
|
|
|
" .type my_tramp2, @function\n"
|
|
|
|
" .globl my_tramp2\n"
|
|
|
|
" my_tramp2:"
|
|
|
|
" lgr %r1,%r15\n"
|
|
|
|
" stmg %r0,%r5,"__stringify(__SF_GPRS)"(%r15)\n"
|
|
|
|
" stg %r14,"__stringify(__SF_GPRS+8*8)"(%r15)\n"
|
|
|
|
" aghi %r15,"__stringify(-STACK_FRAME_OVERHEAD)"\n"
|
|
|
|
" stg %r1,"__stringify(__SF_BACKCHAIN)"(%r15)\n"
|
|
|
|
" lgr %r2,%r0\n"
|
|
|
|
" brasl %r14,my_direct_func2\n"
|
|
|
|
" aghi %r15,"__stringify(STACK_FRAME_OVERHEAD)"\n"
|
|
|
|
" lmg %r0,%r5,"__stringify(__SF_GPRS)"(%r15)\n"
|
|
|
|
" lg %r14,"__stringify(__SF_GPRS+8*8)"(%r15)\n"
|
|
|
|
" lgr %r1,%r0\n"
|
|
|
|
" br %r1\n"
|
|
|
|
" .size my_tramp2, .-my_tramp2\n"
|
|
|
|
" .popsection\n"
|
|
|
|
);
|
|
|
|
|
|
|
|
#endif /* CONFIG_S390 */
|
|
|
|
|
2023-04-27 14:07:00 +00:00
|
|
|
#ifdef CONFIG_ARM64
|
|
|
|
|
|
|
|
asm (
|
|
|
|
" .pushsection .text, \"ax\", @progbits\n"
|
|
|
|
" .type my_tramp1, @function\n"
|
|
|
|
" .globl my_tramp1\n"
|
|
|
|
" my_tramp1:"
|
2023-08-20 11:15:09 +00:00
|
|
|
" hint 34\n" // bti c
|
2023-04-27 14:07:00 +00:00
|
|
|
" sub sp, sp, #32\n"
|
|
|
|
" stp x9, x30, [sp]\n"
|
|
|
|
" str x0, [sp, #16]\n"
|
|
|
|
" mov x0, x30\n"
|
|
|
|
" bl my_direct_func1\n"
|
|
|
|
" ldp x30, x9, [sp]\n"
|
|
|
|
" ldr x0, [sp, #16]\n"
|
|
|
|
" add sp, sp, #32\n"
|
|
|
|
" ret x9\n"
|
|
|
|
" .size my_tramp1, .-my_tramp1\n"
|
|
|
|
|
|
|
|
" .type my_tramp2, @function\n"
|
|
|
|
" .globl my_tramp2\n"
|
|
|
|
" my_tramp2:"
|
2023-08-20 11:15:09 +00:00
|
|
|
" hint 34\n" // bti c
|
2023-04-27 14:07:00 +00:00
|
|
|
" sub sp, sp, #32\n"
|
|
|
|
" stp x9, x30, [sp]\n"
|
|
|
|
" str x0, [sp, #16]\n"
|
|
|
|
" mov x0, x30\n"
|
|
|
|
" bl my_direct_func2\n"
|
|
|
|
" ldp x30, x9, [sp]\n"
|
|
|
|
" ldr x0, [sp, #16]\n"
|
|
|
|
" add sp, sp, #32\n"
|
|
|
|
" ret x9\n"
|
|
|
|
" .size my_tramp2, .-my_tramp2\n"
|
|
|
|
" .popsection\n"
|
|
|
|
);
|
|
|
|
|
|
|
|
#endif /* CONFIG_ARM64 */
|
|
|
|
|
2023-05-01 09:19:53 +00:00
|
|
|
#ifdef CONFIG_LOONGARCH
|
|
|
|
#include <asm/asm.h>
|
|
|
|
|
|
|
|
asm (
|
|
|
|
" .pushsection .text, \"ax\", @progbits\n"
|
|
|
|
" .type my_tramp1, @function\n"
|
|
|
|
" .globl my_tramp1\n"
|
|
|
|
" my_tramp1:\n"
|
|
|
|
" addi.d $sp, $sp, -32\n"
|
|
|
|
" st.d $a0, $sp, 0\n"
|
|
|
|
" st.d $t0, $sp, 8\n"
|
|
|
|
" st.d $ra, $sp, 16\n"
|
|
|
|
" move $a0, $t0\n"
|
|
|
|
" bl my_direct_func1\n"
|
|
|
|
" ld.d $a0, $sp, 0\n"
|
|
|
|
" ld.d $t0, $sp, 8\n"
|
|
|
|
" ld.d $ra, $sp, 16\n"
|
|
|
|
" addi.d $sp, $sp, 32\n"
|
|
|
|
" jr $t0\n"
|
|
|
|
" .size my_tramp1, .-my_tramp1\n"
|
|
|
|
|
|
|
|
" .type my_tramp2, @function\n"
|
|
|
|
" .globl my_tramp2\n"
|
|
|
|
" my_tramp2:\n"
|
|
|
|
" addi.d $sp, $sp, -32\n"
|
|
|
|
" st.d $a0, $sp, 0\n"
|
|
|
|
" st.d $t0, $sp, 8\n"
|
|
|
|
" st.d $ra, $sp, 16\n"
|
|
|
|
" move $a0, $t0\n"
|
|
|
|
" bl my_direct_func2\n"
|
|
|
|
" ld.d $a0, $sp, 0\n"
|
|
|
|
" ld.d $t0, $sp, 8\n"
|
|
|
|
" ld.d $ra, $sp, 16\n"
|
|
|
|
" addi.d $sp, $sp, 32\n"
|
|
|
|
" jr $t0\n"
|
|
|
|
" .size my_tramp2, .-my_tramp2\n"
|
|
|
|
" .popsection\n"
|
|
|
|
);
|
|
|
|
|
|
|
|
#endif /* CONFIG_LOONGARCH */
|
|
|
|
|
2024-10-30 07:08:49 +00:00
|
|
|
#ifdef CONFIG_PPC
|
|
|
|
#include <asm/ppc_asm.h>
|
|
|
|
|
|
|
|
#ifdef CONFIG_PPC64
|
|
|
|
#define STACK_FRAME_SIZE 48
|
|
|
|
#else
|
|
|
|
#define STACK_FRAME_SIZE 24
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#if defined(CONFIG_PPC64_ELF_ABI_V2) && !defined(CONFIG_PPC_KERNEL_PCREL)
|
|
|
|
#define PPC64_TOC_SAVE_AND_UPDATE \
|
|
|
|
" std 2, 24(1)\n" \
|
|
|
|
" bcl 20, 31, 1f\n" \
|
|
|
|
" 1: mflr 12\n" \
|
|
|
|
" ld 2, (99f - 1b)(12)\n"
|
|
|
|
#define PPC64_TOC_RESTORE \
|
|
|
|
" ld 2, 24(1)\n"
|
|
|
|
#define PPC64_TOC \
|
|
|
|
" 99: .quad .TOC.@tocbase\n"
|
|
|
|
#else
|
|
|
|
#define PPC64_TOC_SAVE_AND_UPDATE ""
|
|
|
|
#define PPC64_TOC_RESTORE ""
|
|
|
|
#define PPC64_TOC ""
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifdef CONFIG_PPC_FTRACE_OUT_OF_LINE
|
|
|
|
#define PPC_FTRACE_RESTORE_LR \
|
|
|
|
PPC_LL" 0, "__stringify(PPC_LR_STKOFF)"(1)\n" \
|
|
|
|
" mtlr 0\n"
|
|
|
|
#define PPC_FTRACE_RET \
|
|
|
|
" blr\n"
|
|
|
|
#define PPC_FTRACE_RECOVER_IP \
|
|
|
|
" lwz 8, 4(3)\n" \
|
|
|
|
" li 9, 6\n" \
|
|
|
|
" slw 8, 8, 9\n" \
|
|
|
|
" sraw 8, 8, 9\n" \
|
|
|
|
" add 3, 3, 8\n" \
|
|
|
|
" addi 3, 3, 4\n"
|
|
|
|
#else
|
|
|
|
#define PPC_FTRACE_RESTORE_LR \
|
|
|
|
PPC_LL" 0, "__stringify(PPC_LR_STKOFF)"(1)\n" \
|
|
|
|
" mtctr 0\n"
|
|
|
|
#define PPC_FTRACE_RET \
|
|
|
|
" mtlr 0\n" \
|
|
|
|
" bctr\n"
|
|
|
|
#define PPC_FTRACE_RECOVER_IP ""
|
|
|
|
#endif
|
|
|
|
|
|
|
|
asm (
|
|
|
|
" .pushsection .text, \"ax\", @progbits\n"
|
|
|
|
" .type my_tramp1, @function\n"
|
|
|
|
" .globl my_tramp1\n"
|
|
|
|
" my_tramp1:\n"
|
|
|
|
PPC_STL" 0, "__stringify(PPC_LR_STKOFF)"(1)\n"
|
|
|
|
PPC_STLU" 1, -"__stringify(STACK_FRAME_MIN_SIZE)"(1)\n"
|
|
|
|
" mflr 0\n"
|
|
|
|
PPC_STL" 0, "__stringify(PPC_LR_STKOFF)"(1)\n"
|
|
|
|
PPC_STLU" 1, -"__stringify(STACK_FRAME_SIZE)"(1)\n"
|
|
|
|
PPC64_TOC_SAVE_AND_UPDATE
|
|
|
|
PPC_STL" 3, "__stringify(STACK_FRAME_MIN_SIZE)"(1)\n"
|
|
|
|
" mr 3, 0\n"
|
|
|
|
PPC_FTRACE_RECOVER_IP
|
|
|
|
" bl my_direct_func1\n"
|
|
|
|
PPC_LL" 3, "__stringify(STACK_FRAME_MIN_SIZE)"(1)\n"
|
|
|
|
PPC64_TOC_RESTORE
|
|
|
|
" addi 1, 1, "__stringify(STACK_FRAME_SIZE)"\n"
|
|
|
|
PPC_FTRACE_RESTORE_LR
|
|
|
|
" addi 1, 1, "__stringify(STACK_FRAME_MIN_SIZE)"\n"
|
|
|
|
PPC_LL" 0, "__stringify(PPC_LR_STKOFF)"(1)\n"
|
|
|
|
PPC_FTRACE_RET
|
|
|
|
" .size my_tramp1, .-my_tramp1\n"
|
|
|
|
|
|
|
|
" .type my_tramp2, @function\n"
|
|
|
|
" .globl my_tramp2\n"
|
|
|
|
" my_tramp2:\n"
|
|
|
|
PPC_STL" 0, "__stringify(PPC_LR_STKOFF)"(1)\n"
|
|
|
|
PPC_STLU" 1, -"__stringify(STACK_FRAME_MIN_SIZE)"(1)\n"
|
|
|
|
" mflr 0\n"
|
|
|
|
PPC_STL" 0, "__stringify(PPC_LR_STKOFF)"(1)\n"
|
|
|
|
PPC_STLU" 1, -"__stringify(STACK_FRAME_SIZE)"(1)\n"
|
|
|
|
PPC64_TOC_SAVE_AND_UPDATE
|
|
|
|
PPC_STL" 3, "__stringify(STACK_FRAME_MIN_SIZE)"(1)\n"
|
|
|
|
" mr 3, 0\n"
|
|
|
|
PPC_FTRACE_RECOVER_IP
|
|
|
|
" bl my_direct_func2\n"
|
|
|
|
PPC_LL" 3, "__stringify(STACK_FRAME_MIN_SIZE)"(1)\n"
|
|
|
|
PPC64_TOC_RESTORE
|
|
|
|
" addi 1, 1, "__stringify(STACK_FRAME_SIZE)"\n"
|
|
|
|
PPC_FTRACE_RESTORE_LR
|
|
|
|
" addi 1, 1, "__stringify(STACK_FRAME_MIN_SIZE)"\n"
|
|
|
|
PPC_LL" 0, "__stringify(PPC_LR_STKOFF)"(1)\n"
|
|
|
|
PPC_FTRACE_RET
|
|
|
|
PPC64_TOC
|
|
|
|
" .size my_tramp2, .-my_tramp2\n"
|
|
|
|
" .popsection\n"
|
|
|
|
);
|
|
|
|
|
|
|
|
#endif /* CONFIG_PPC */
|
|
|
|
|
2021-12-06 18:20:32 +00:00
|
|
|
static unsigned long my_tramp = (unsigned long)my_tramp1;
|
|
|
|
static unsigned long tramps[2] = {
|
|
|
|
(unsigned long)my_tramp1,
|
|
|
|
(unsigned long)my_tramp2,
|
|
|
|
};
|
|
|
|
|
|
|
|
static struct ftrace_ops direct;
|
|
|
|
|
|
|
|
static int simple_thread(void *arg)
|
|
|
|
{
|
|
|
|
static int t;
|
|
|
|
int ret = 0;
|
|
|
|
|
|
|
|
while (!kthread_should_stop()) {
|
|
|
|
set_current_state(TASK_INTERRUPTIBLE);
|
|
|
|
schedule_timeout(2 * HZ);
|
|
|
|
|
|
|
|
if (ret)
|
|
|
|
continue;
|
|
|
|
t ^= 1;
|
2023-03-21 14:04:21 +00:00
|
|
|
ret = modify_ftrace_direct(&direct, tramps[t]);
|
2021-12-06 18:20:32 +00:00
|
|
|
if (!ret)
|
|
|
|
my_tramp = tramps[t];
|
|
|
|
WARN_ON_ONCE(ret);
|
|
|
|
}
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
static struct task_struct *simple_tsk;
|
|
|
|
|
|
|
|
static int __init ftrace_direct_multi_init(void)
|
|
|
|
{
|
|
|
|
int ret;
|
|
|
|
|
|
|
|
ftrace_set_filter_ip(&direct, (unsigned long) wake_up_process, 0, 0);
|
|
|
|
ftrace_set_filter_ip(&direct, (unsigned long) schedule, 0, 0);
|
|
|
|
|
2023-03-21 14:04:21 +00:00
|
|
|
ret = register_ftrace_direct(&direct, my_tramp);
|
2021-12-06 18:20:32 +00:00
|
|
|
|
|
|
|
if (!ret)
|
|
|
|
simple_tsk = kthread_run(simple_thread, NULL, "event-sample-fn");
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
|
|
|
static void __exit ftrace_direct_multi_exit(void)
|
|
|
|
{
|
|
|
|
kthread_stop(simple_tsk);
|
2023-03-21 14:04:21 +00:00
|
|
|
unregister_ftrace_direct(&direct, my_tramp, true);
|
2021-12-06 18:20:32 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
module_init(ftrace_direct_multi_init);
|
|
|
|
module_exit(ftrace_direct_multi_exit);
|
|
|
|
|
|
|
|
MODULE_AUTHOR("Jiri Olsa");
|
2023-03-21 14:04:21 +00:00
|
|
|
MODULE_DESCRIPTION("Example use case of using modify_ftrace_direct()");
|
2021-12-06 18:20:32 +00:00
|
|
|
MODULE_LICENSE("GPL");
|