/* SPDX-License-Identifier: GPL-2.0 */ #ifndef _ASM_X86_FRAME_H #define _ASM_X86_FRAME_H #include <asm/asm.h> /* * These are stack frame creation macros. They should be used by every * callable non-leaf asm function to make kernel stack traces more reliable. */ #ifdef [31mCONFIG_FRAME_POINTER[0m #ifdef __ASSEMBLY__ .macro FRAME_BEGIN push %_ASM_BP _ASM_MOV %_ASM_SP, %_ASM_BP .endm .macro FRAME_END pop %_ASM_BP .endm #ifdef [31mCONFIG_X86_64[0m /* * This is a sneaky trick to help the unwinder find pt_regs on the stack. The * frame pointer is replaced with an encoded pointer to pt_regs. The encoding * is just setting the LSB, which makes it an invalid stack address and is also * a signal to the unwinder that it's a pt_regs pointer in disguise. * * NOTE: This macro must be used *after* PUSH_AND_CLEAR_REGS because it corrupts * the original rbp. */ .macro ENCODE_FRAME_POINTER ptregs_offset=0 leaq 1+\ptregs_offset(%rsp), %rbp .endm #else /* !CONFIG_X86_64 */ /* * This is a sneaky trick to help the unwinder find pt_regs on the stack. The * frame pointer is replaced with an encoded pointer to pt_regs. The encoding * is just clearing the MSB, which makes it an invalid stack address and is also * a signal to the unwinder that it's a pt_regs pointer in disguise. * * NOTE: This macro must be used *after* SAVE_ALL because it corrupts the * original ebp. */ .macro ENCODE_FRAME_POINTER mov %esp, %ebp andl $0x7fffffff, %ebp .endm #endif /* CONFIG_X86_64 */ #else /* !__ASSEMBLY__ */ #define FRAME_BEGIN \ "push %" _ASM_BP "\n" \ _ASM_MOV "%" _ASM_SP ", %" _ASM_BP "\n" #define FRAME_END "pop %" _ASM_BP "\n" #ifdef [31mCONFIG_X86_64[0m #define ENCODE_FRAME_POINTER \ "lea 1(%rsp), %rbp\n\t" #else /* !CONFIG_X86_64 */ #define ENCODE_FRAME_POINTER \ "movl %esp, %ebp\n\t" \ "andl $0x7fffffff, %ebp\n\t" #endif /* CONFIG_X86_64 */ #endif /* __ASSEMBLY__ */ #define FRAME_OFFSET __ASM_SEL(4, 8) #else /* !CONFIG_FRAME_POINTER */ #ifdef __ASSEMBLY__ .macro ENCODE_FRAME_POINTER ptregs_offset=0 .endm #else /* !__ASSEMBLY */ #define ENCODE_FRAME_POINTER #endif #define FRAME_BEGIN #define FRAME_END #define FRAME_OFFSET 0 #endif /* CONFIG_FRAME_POINTER */ #endif /* _ASM_X86_FRAME_H */ |