From d1254b12c93e1e586137a2ffef71fd33cf273f35 Mon Sep 17 00:00:00 2001 From: Jeff Dike Date: Thu, 30 Aug 2007 23:56:20 -0700 Subject: [PATCH] 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: Jeff Dike Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/um/os-Linux/sys-x86_64/registers.c | 15 ++++++++++ arch/um/sys-x86_64/ptrace.c | 6 ---- include/asm-um/elf-x86_64.h | 40 +++++++++++++++++++++++++ 3 files changed, 55 insertions(+), 6 deletions(-) diff --git a/arch/um/os-Linux/sys-x86_64/registers.c b/arch/um/os-Linux/sys-x86_64/registers.c index e6fc2179d1bc..9467315b8059 100644 --- a/arch/um/os-Linux/sys-x86_64/registers.c +++ b/arch/um/os-Linux/sys-x86_64/registers.c @@ -4,6 +4,7 @@ */ #include +#include #include #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)); diff --git a/arch/um/sys-x86_64/ptrace.c b/arch/um/sys-x86_64/ptrace.c index 55b66e09a98c..1970d78aa528 100644 --- a/arch/um/sys-x86_64/ptrace.c +++ b/arch/um/sys-x86_64/ptrace.c @@ -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"); diff --git a/include/asm-um/elf-x86_64.h b/include/asm-um/elf-x86_64.h index 8a8246d03936..bfe27aa2c9c4 100644 --- a/include/asm-um/elf-x86_64.h +++ b/include/asm-um/elf-x86_64.h @@ -6,7 +6,9 @@ #ifndef __UM_ELF_X86_64_H #define __UM_ELF_X86_64_H +#include #include +#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); -- GitLab