3c88c692c2
Currently pt_regs on x86_32 has an oddity in that kernel regs (!user_mode(regs)) are short two entries (esp/ss). This means that any code trying to use them (typically: regs->sp) needs to jump through some unfortunate hoops. Change the entry code to fix this up and create a full pt_regs frame. This then simplifies various trampolines in ftrace and kprobes, the stack unwinder, ptrace, kdump and kgdb. Much thanks to Josh for help with the cleanups! Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
109 lines
2.7 KiB
C
109 lines
2.7 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
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#ifndef __X86_KERNEL_KPROBES_COMMON_H
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#define __X86_KERNEL_KPROBES_COMMON_H
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/* Kprobes and Optprobes common header */
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#include <asm/asm.h>
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#include <asm/frame.h>
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#ifdef CONFIG_X86_64
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#define SAVE_REGS_STRING \
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/* Skip cs, ip, orig_ax. */ \
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" subq $24, %rsp\n" \
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" pushq %rdi\n" \
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" pushq %rsi\n" \
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" pushq %rdx\n" \
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" pushq %rcx\n" \
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" pushq %rax\n" \
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" pushq %r8\n" \
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" pushq %r9\n" \
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" pushq %r10\n" \
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" pushq %r11\n" \
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" pushq %rbx\n" \
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" pushq %rbp\n" \
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" pushq %r12\n" \
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" pushq %r13\n" \
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" pushq %r14\n" \
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" pushq %r15\n" \
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ENCODE_FRAME_POINTER
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#define RESTORE_REGS_STRING \
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" popq %r15\n" \
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" popq %r14\n" \
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" popq %r13\n" \
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" popq %r12\n" \
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" popq %rbp\n" \
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" popq %rbx\n" \
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" popq %r11\n" \
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" popq %r10\n" \
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" popq %r9\n" \
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" popq %r8\n" \
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" popq %rax\n" \
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" popq %rcx\n" \
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" popq %rdx\n" \
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" popq %rsi\n" \
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" popq %rdi\n" \
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/* Skip orig_ax, ip, cs */ \
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" addq $24, %rsp\n"
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#else
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#define SAVE_REGS_STRING \
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/* Skip cs, ip, orig_ax and gs. */ \
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" subl $4*4, %esp\n" \
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" pushl %fs\n" \
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" pushl %es\n" \
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" pushl %ds\n" \
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" pushl %eax\n" \
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" pushl %ebp\n" \
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" pushl %edi\n" \
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" pushl %esi\n" \
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" pushl %edx\n" \
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" pushl %ecx\n" \
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" pushl %ebx\n" \
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ENCODE_FRAME_POINTER
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#define RESTORE_REGS_STRING \
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" popl %ebx\n" \
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" popl %ecx\n" \
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" popl %edx\n" \
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" popl %esi\n" \
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" popl %edi\n" \
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" popl %ebp\n" \
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" popl %eax\n" \
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/* Skip ds, es, fs, gs, orig_ax, ip, and cs. */\
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" addl $7*4, %esp\n"
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#endif
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/* Ensure if the instruction can be boostable */
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extern int can_boost(struct insn *insn, void *orig_addr);
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/* Recover instruction if given address is probed */
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extern unsigned long recover_probed_instruction(kprobe_opcode_t *buf,
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unsigned long addr);
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/*
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* Copy an instruction and adjust the displacement if the instruction
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* uses the %rip-relative addressing mode.
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*/
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extern int __copy_instruction(u8 *dest, u8 *src, u8 *real, struct insn *insn);
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/* Generate a relative-jump/call instruction */
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extern void synthesize_reljump(void *dest, void *from, void *to);
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extern void synthesize_relcall(void *dest, void *from, void *to);
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#ifdef CONFIG_OPTPROBES
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extern int setup_detour_execution(struct kprobe *p, struct pt_regs *regs, int reenter);
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extern unsigned long __recover_optprobed_insn(kprobe_opcode_t *buf, unsigned long addr);
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#else /* !CONFIG_OPTPROBES */
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static inline int setup_detour_execution(struct kprobe *p, struct pt_regs *regs, int reenter)
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{
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return 0;
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}
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static inline unsigned long __recover_optprobed_insn(kprobe_opcode_t *buf, unsigned long addr)
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{
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return addr;
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}
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#endif
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#endif
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