Commit d1254b12 authored by Jeff Dike's avatar Jeff Dike Committed by Linus Torvalds
Browse files

uml: fix x86_64 core dump crash



Stop UML crashing when trying to dump a process core on x86_64.  This is the
minimal fix to stop the crash - more things are broken here, and patches are
forthcoming.

The immediate thing to do is define ELF_CORE_COPY_REGS and
ELF_CORE_COPY_FPREGS.  Defining ELF_CORE_COPY_FPREGS allows dump_fpu to go
away.  It is defined in terms of save_fp_registers, so that needs to be added.
Signed-off-by: default avatarJeff Dike <jdike@linux.intel.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent c7ec16da
......@@ -4,6 +4,7 @@
*/
#include <errno.h>
#include <sys/ptrace.h>
#include <string.h>
#include "ptrace_user.h"
#include "uml-config.h"
......@@ -17,6 +18,20 @@
static unsigned long exec_regs[MAX_REG_NR];
static unsigned long exec_fp_regs[HOST_FP_SIZE];
int save_fp_registers(int pid, unsigned long *fp_regs)
{
if(ptrace(PTRACE_GETFPREGS, pid, 0, fp_regs) < 0)
return -errno;
return 0;
}
int restore_fp_registers(int pid, unsigned long *fp_regs)
{
if(ptrace(PTRACE_SETFPREGS, pid, 0, fp_regs) < 0)
return -errno;
return 0;
}
void init_thread_registers(union uml_pt_regs *to)
{
memcpy(to->skas.regs, exec_regs, sizeof(to->skas.regs));
......
......@@ -156,12 +156,6 @@ int is_syscall(unsigned long addr)
return(instr == 0x050f);
}
int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu )
{
panic("dump_fpu");
return(1);
}
int get_fpregs(unsigned long buf, struct task_struct *child)
{
panic("get_fpregs");
......
......@@ -6,7 +6,9 @@
#ifndef __UM_ELF_X86_64_H
#define __UM_ELF_X86_64_H
#include <linux/sched.h>
#include <asm/user.h>
#include "skas.h"
/* x86-64 relocation types, taken from asm-x86_64/elf.h */
#define R_X86_64_NONE 0 /* No reloc */
......@@ -64,6 +66,44 @@ typedef struct { } elf_fpregset_t;
PT_REGS_R15(regs) = 0; \
} while (0)
#define ELF_CORE_COPY_REGS(pr_reg, regs) \
(pr_reg)[0] = (regs)->regs.gp[0]; \
(pr_reg)[1] = (regs)->regs.gp[1]; \
(pr_reg)[2] = (regs)->regs.gp[2]; \
(pr_reg)[3] = (regs)->regs.gp[3]; \
(pr_reg)[4] = (regs)->regs.gp[4]; \
(pr_reg)[5] = (regs)->regs.gp[5]; \
(pr_reg)[6] = (regs)->regs.gp[6]; \
(pr_reg)[7] = (regs)->regs.gp[7]; \
(pr_reg)[8] = (regs)->regs.gp[8]; \
(pr_reg)[9] = (regs)->regs.gp[9]; \
(pr_reg)[10] = (regs)->regs.gp[10]; \
(pr_reg)[11] = (regs)->regs.gp[11]; \
(pr_reg)[12] = (regs)->regs.gp[12]; \
(pr_reg)[13] = (regs)->regs.gp[13]; \
(pr_reg)[14] = (regs)->regs.gp[14]; \
(pr_reg)[15] = (regs)->regs.gp[15]; \
(pr_reg)[16] = (regs)->regs.gp[16]; \
(pr_reg)[17] = (regs)->regs.gp[17]; \
(pr_reg)[18] = (regs)->regs.gp[18]; \
(pr_reg)[19] = (regs)->regs.gp[19]; \
(pr_reg)[20] = (regs)->regs.gp[20]; \
(pr_reg)[21] = current->thread.arch.fs; \
(pr_reg)[22] = 0; \
(pr_reg)[23] = 0; \
(pr_reg)[24] = 0; \
(pr_reg)[25] = 0; \
(pr_reg)[26] = 0;
static inline int elf_core_copy_fpregs(struct task_struct *t,
elf_fpregset_t *fpu)
{
int cpu = current_thread->cpu;
return save_fp_registers(userspace_pid[cpu], (unsigned long *) fpu);
}
#define ELF_CORE_COPY_FPREGS(t, fpu) elf_core_copy_fpregs(t, fpu)
#ifdef TIF_IA32 /* XXX */
#error XXX, indeed
clear_thread_flag(TIF_IA32);
......
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