1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_X86_USER_64_H
3 #define _ASM_X86_USER_64_H
7 /* Core file format: The core file is written in such a way that gdb
8 can understand it and provide useful information to the user.
9 There are quite a number of obstacles to being able to view the
10 contents of the floating point registers, and until these are
11 solved you will not be able to view the contents of them.
12 Actually, you can read in the core file and look at the contents of
13 the user struct to find out what the floating point registers
16 The actual file contents are as follows:
17 UPAGE: 1 page consisting of a user struct that tells gdb what is present
18 in the file. Directly after this is a copy of the task_struct, which
19 is currently not used by gdb, but it may come in useful at some point.
20 All of the registers are stored as part of the upage. The upage should
21 always be only one page.
22 DATA: The data area is stored. We use current->end_text to
23 current->brk to pick up all of the user variables, plus any memory
24 that may have been malloced. No attempt is made to determine if a page
25 is demand-zero or if a page is totally unused, we just cover the entire
26 range. All of the addresses are rounded in such a way that an integral
27 number of pages is written.
28 STACK: We need the stack information in order to get a meaningful
29 backtrace. We need to write the data from (esp) to
30 current->start_stack, so we round each of these off in order to be able
31 to write an integer number of pages.
32 The minimum core file size is 3 pages, or 12288 bytes. */
35 * Pentium III FXSR, SSE support
36 * Gareth Hughes <gareth@valinux.com>, May 2000
38 * Provide support for the GDB 5.0+ PTRACE_{GET|SET}FPXREGS requests for
39 * interacting with the FXSR-format floating point environment. Floating
40 * point data can be accessed in the regular format in the usual manner,
41 * and both the standard and SIMD floating point data can be accessed via
42 * the new ptrace requests. In either case, changes to the FPU environment
43 * will be reflected in the task's state as expected.
45 * x86-64 support by Andi Kleen.
48 /* This matches the 64bit FXSAVE format as defined by AMD. It is the same
49 as the 32bit format defined by Intel, except that the selector:offset pairs
50 for data and eip are replaced with flat 64bit pointers. */
51 struct user_i387_struct {
54 unsigned short twd; /* Note this is not the same as
55 the 32bit/x87/FSAVE twd */
61 __u32 st_space[32]; /* 8*16 bytes for each FP-reg = 128 bytes */
62 __u32 xmm_space[64]; /* 16*16 bytes for each XMM-reg = 256 bytes */
67 * Segment register layout in coredumps.
69 struct user_regs_struct {
85 unsigned long orig_ax;
91 unsigned long fs_base;
92 unsigned long gs_base;
99 /* When the kernel dumps core, it starts by dumping the user struct -
100 this will be used by gdb to figure out where the data and stack segments
101 are within the file, and what virtual addresses to use. */
104 /* We start with the registers, to mimic the way that "memory" is returned
105 from the ptrace(3,...) function. */
106 struct user_regs_struct regs; /* Where the registers are actually stored */
107 /* ptrace does not yet supply these. Someday.... */
108 int u_fpvalid; /* True if math co-processor being used. */
109 /* for this mess. Not yet used. */
111 struct user_i387_struct i387; /* Math Co-processor registers. */
112 /* The rest of this junk is to help gdb figure out what goes where */
113 unsigned long int u_tsize; /* Text segment size (pages). */
114 unsigned long int u_dsize; /* Data segment size (pages). */
115 unsigned long int u_ssize; /* Stack segment size (pages). */
116 unsigned long start_code; /* Starting virtual address of text. */
117 unsigned long start_stack; /* Starting virtual address of stack area.
118 This is actually the bottom of the stack,
119 the top of the stack is always found in the
121 long int signal; /* Signal that caused the core dump. */
122 int reserved; /* No longer used */
124 unsigned long u_ar0; /* Used by gdb to help find the values for */
126 struct user_i387_struct *u_fpstate; /* Math Co-processor pointer. */
127 unsigned long magic; /* To uniquely identify a core file */
128 char u_comm[32]; /* User command that was responsible */
129 unsigned long u_debugreg[8];
130 unsigned long error_code; /* CPU error code or 0 */
131 unsigned long fault_address; /* CR3 or 0 */
133 #define NBPG PAGE_SIZE
135 #define HOST_TEXT_START_ADDR (u.start_code)
136 #define HOST_STACK_END_ADDR (u.start_stack + u.u_ssize * NBPG)
138 #endif /* _ASM_X86_USER_64_H */