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[PATCH] uml: S390 preparation, abstract host page fault data

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This patch removes the arch-specific fault/trap-infos from thread and
skas-regs.

It adds a new struct faultinfo, that is arch-specific defined in
sysdep/faultinfo.h.

The structure is inserted in thread.arch and thread.regs.skas and
thread.regs.tt

Now, segv and other trap-handlers can copy the contents from regs.X.faultinfo
to thread.arch.faultinfo with one simple assignment.

Also, the number of macros necessary is reduced to

FAULT_ADDRESS(struct faultinfo)
    extracts the faulting address from faultinfo

FAULT_WRITE(struct faultinfo)
    extracts the "is_write" flag

SEGV_IS_FIXABLE(struct faultinfo)
    is true for the fixable segvs, i.e. (TRAP == 14)
    on i386

UPT_FAULTINFO(regs)
    result is (struct faultinfo *) to the faultinfo
    in regs->skas.faultinfo

GET_FAULTINFO_FROM_SC(struct faultinfo, struct sigcontext *)
    copies the relevant parts of the sigcontext to
    struct faultinfo.

On SIGSEGV, call user_signal() instead of handle_segv(), if the architecture
provides the information needed in PTRACE_FAULTINFO, or if PTRACE_FAULTINFO is
missing, because segv-stub will provide the info.

The benefit of the change is, that in case of a non-fixable SIGSEGV, we can
give user processes a SIGSEGV, instead of possibly looping on pagefault
handling.

Since handle_segv() sikked arch_fixup() implicitly by passing ip==0 to segv(),
I changed segv() to call arch_fixup() only, if !is_user.

Signed-off-by: Bodo Stroesser <bstroesser@fujitsu-siemens.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Bodo Stroesser 2005-05-05 16:15:31 -07:00 committed by Linus Torvalds
parent ea66e8a3b6
commit c578455a3e
24 changed files with 279 additions and 115 deletions
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7
arch/um/include/kern_util.h
View file

@ -8,6 +8,7 @@
#include "linux/threads.h"
#include "sysdep/ptrace.h"
#include "sysdep/faultinfo.h"
extern int ncpus;
extern char *linux_prog;
@ -31,8 +32,8 @@ extern int current_pid(void);
extern unsigned long alloc_stack(int order, int atomic);
extern int do_signal(void);
extern int is_stack_fault(unsigned long sp);
extern unsigned long segv(unsigned long address, unsigned long ip,
int is_write, int is_user, void *sc);
extern unsigned long segv(struct faultinfo fi, unsigned long ip,
int is_user, void *sc);
extern int handle_page_fault(unsigned long address, unsigned long ip,
int is_write, int is_user, int *code_out);
extern void syscall_ready(void);
@ -82,7 +83,7 @@ extern void timer_irq(union uml_pt_regs *regs);
extern void unprotect_stack(unsigned long stack);
extern void do_uml_exitcalls(void);
extern int attach_debugger(int idle_pid, int pid, int stop);
extern void bad_segv(unsigned long address, unsigned long ip, int is_write);
extern void bad_segv(struct faultinfo fi, unsigned long ip);
extern int config_gdb(char *str);
extern int remove_gdb(void);
extern char *uml_strdup(char *string);

29
arch/um/include/sysdep-i386/faultinfo.h Normal file
View file

@ -0,0 +1,29 @@
/*
* Copyright (C) 2004 Fujitsu Siemens Computers GmbH
* Author: Bodo Stroesser <bstroesser@fujitsu-siemens.com>
* Licensed under the GPL
*/
#ifndef __FAULTINFO_I386_H
#define __FAULTINFO_I386_H
/* this structure contains the full arch-specific faultinfo
* from the traps.
* On i386, ptrace_faultinfo unfortunately doesn't provide
* all the info, since trap_no is missing.
* All common elements are defined at the same position in
* both structures, thus making it easy to copy the
* contents without knowledge about the structure elements.
*/
struct faultinfo {
int error_code; /* in ptrace_faultinfo misleadingly called is_write */
unsigned long cr2; /* in ptrace_faultinfo called addr */
int trap_no; /* missing in ptrace_faultinfo */
};
#define FAULT_WRITE(fi) ((fi).error_code & 2)
#define FAULT_ADDRESS(fi) ((fi).cr2)
#define PTRACE_FULL_FAULTINFO 0
#endif

23
arch/um/include/sysdep-i386/ptrace.h
View file

@ -31,6 +31,7 @@ extern int sysemu_supported;
#ifdef UML_CONFIG_MODE_SKAS
#include "skas_ptregs.h"
#include "sysdep/faultinfo.h"
#define REGS_IP(r) ((r)[HOST_IP])
#define REGS_SP(r) ((r)[HOST_SP])
@ -53,12 +54,6 @@ extern int sysemu_supported;
#define REGS_RESTART_SYSCALL(r) IP_RESTART_SYSCALL(REGS_IP(r))
#define REGS_SEGV_IS_FIXABLE(r) SEGV_IS_FIXABLE((r)->trap_type)
#define REGS_FAULT_ADDR(r) ((r)->fault_addr)
#define REGS_FAULT_WRITE(r) FAULT_WRITE((r)->fault_type)
#endif
#ifndef PTRACE_SYSEMU_SINGLESTEP
#define PTRACE_SYSEMU_SINGLESTEP 32
@ -71,6 +66,7 @@ union uml_pt_regs {
struct tt_regs {
long syscall;
void *sc;
struct faultinfo faultinfo;
} tt;
#endif
#ifdef UML_CONFIG_MODE_SKAS
@ -78,9 +74,7 @@ union uml_pt_regs {
unsigned long regs[HOST_FRAME_SIZE];
unsigned long fp[HOST_FP_SIZE];
unsigned long xfp[HOST_XFP_SIZE];
unsigned long fault_addr;
unsigned long fault_type;
unsigned long trap_type;
struct faultinfo faultinfo;
long syscall;
int is_user;
} skas;
@ -217,15 +211,8 @@ struct syscall_args {
#define UPT_SYSCALL_NR(r) UPT_ORIG_EAX(r)
#define UPT_SYSCALL_RET(r) UPT_EAX(r)
#define UPT_SEGV_IS_FIXABLE(r) \
CHOOSE_MODE(SC_SEGV_IS_FIXABLE(UPT_SC(r)), \
REGS_SEGV_IS_FIXABLE(&r->skas))
#define UPT_FAULT_ADDR(r) \
__CHOOSE_MODE(SC_FAULT_ADDR(UPT_SC(r)), REGS_FAULT_ADDR(&r->skas))
#define UPT_FAULT_WRITE(r) \
CHOOSE_MODE(SC_FAULT_WRITE(UPT_SC(r)), REGS_FAULT_WRITE(&r->skas))
#define UPT_FAULTINFO(r) \
CHOOSE_MODE((&(r)->tt.faultinfo), (&(r)->skas.faultinfo))
#endif

19
arch/um/include/sysdep-i386/sigcontext.h
View file

@ -13,15 +13,12 @@
#define SC_RESTART_SYSCALL(sc) IP_RESTART_SYSCALL(SC_IP(sc))
#define SC_SET_SYSCALL_RETURN(sc, result) SC_EAX(sc) = (result)
#define SC_FAULT_ADDR(sc) SC_CR2(sc)
#define SC_FAULT_TYPE(sc) SC_ERR(sc)
#define FAULT_WRITE(err) (err & 2)
#define TO_SC_ERR(is_write) ((is_write) ? 2 : 0)
#define SC_FAULT_WRITE(sc) (FAULT_WRITE(SC_ERR(sc)))
#define SC_TRAP_TYPE(sc) SC_TRAPNO(sc)
#define GET_FAULTINFO_FROM_SC(fi,sc) \
{ \
(fi).cr2 = SC_CR2(sc); \
(fi).error_code = SC_ERR(sc); \
(fi).trap_no = SC_TRAPNO(sc); \
}
/* ptrace expects that, at the start of a system call, %eax contains
* -ENOSYS, so this makes it so.
@ -29,9 +26,7 @@
#define SC_START_SYSCALL(sc) do SC_EAX(sc) = -ENOSYS; while(0)
/* This is Page Fault */
#define SEGV_IS_FIXABLE(trap) (trap == 14)
#define SC_SEGV_IS_FIXABLE(sc) (SEGV_IS_FIXABLE(SC_TRAPNO(sc)))
#define SEGV_IS_FIXABLE(fi) ((fi)->trap_no == 14)
extern unsigned long *sc_sigmask(void *sc_ptr);
extern int sc_get_fpregs(unsigned long buf, void *sc_ptr);

22
arch/um/include/sysdep-i386/skas_ptrace.h Normal file
View file

@ -0,0 +1,22 @@
/*
* Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
* Licensed under the GPL
*/
#ifndef __SYSDEP_I386_SKAS_PTRACE_H
#define __SYSDEP_I386_SKAS_PTRACE_H
struct ptrace_faultinfo {
int is_write;
unsigned long addr;
};
struct ptrace_ldt {
int func;
void *ptr;
unsigned long bytecount;
};
#define PTRACE_LDT 54
#endif

22
arch/um/include/sysdep-ia64/skas_ptrace.h Normal file
View file

@ -0,0 +1,22 @@
/*
* Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
* Licensed under the GPL
*/
#ifndef __SYSDEP_IA64_SKAS_PTRACE_H
#define __SYSDEP_IA64_SKAS_PTRACE_H
struct ptrace_faultinfo {
int is_write;
unsigned long addr;
};
struct ptrace_ldt {
int func;
void *ptr;
unsigned long bytecount;
};
#define PTRACE_LDT 54
#endif

22
arch/um/include/sysdep-ppc/skas_ptrace.h Normal file
View file

@ -0,0 +1,22 @@
/*
* Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
* Licensed under the GPL
*/
#ifndef __SYSDEP_PPC_SKAS_PTRACE_H
#define __SYSDEP_PPC_SKAS_PTRACE_H
struct ptrace_faultinfo {
int is_write;
unsigned long addr;
};
struct ptrace_ldt {
int func;
void *ptr;
unsigned long bytecount;
};
#define PTRACE_LDT 54
#endif

29
arch/um/include/sysdep-x86_64/faultinfo.h Normal file
View file

@ -0,0 +1,29 @@
/*
* Copyright (C) 2004 Fujitsu Siemens Computers GmbH
* Author: Bodo Stroesser <bstroesser@fujitsu-siemens.com>
* Licensed under the GPL
*/
#ifndef __FAULTINFO_X86_64_H
#define __FAULTINFO_X86_64_H
/* this structure contains the full arch-specific faultinfo
* from the traps.
* On i386, ptrace_faultinfo unfortunately doesn't provide
* all the info, since trap_no is missing.
* All common elements are defined at the same position in
* both structures, thus making it easy to copy the
* contents without knowledge about the structure elements.
*/
struct faultinfo {
int error_code; /* in ptrace_faultinfo misleadingly called is_write */
unsigned long cr2; /* in ptrace_faultinfo called addr */
int trap_no; /* missing in ptrace_faultinfo */
};
#define FAULT_WRITE(fi) ((fi).error_code & 2)
#define FAULT_ADDRESS(fi) ((fi).cr2)
#define PTRACE_FULL_FAULTINFO 1
#endif

16
arch/um/include/sysdep-x86_64/ptrace.h
View file

@ -9,6 +9,7 @@
#include "uml-config.h"
#include "user_constants.h"
#include "sysdep/faultinfo.h"
#define MAX_REG_OFFSET (UM_FRAME_SIZE)
#define MAX_REG_NR ((MAX_REG_OFFSET) / sizeof(unsigned long))
@ -83,6 +84,7 @@ union uml_pt_regs {
long syscall;
unsigned long orig_rax;
void *sc;
struct faultinfo faultinfo;
} tt;
#endif
#ifdef UML_CONFIG_MODE_SKAS
@ -90,9 +92,7 @@ union uml_pt_regs {
/* XXX */
unsigned long regs[27];
unsigned long fp[65];
unsigned long fault_addr;
unsigned long fault_type;
unsigned long trap_type;
struct faultinfo faultinfo;
long syscall;
int is_user;
} skas;
@ -241,14 +241,8 @@ struct syscall_args {
CHOOSE_MODE(SC_SEGV_IS_FIXABLE(UPT_SC(r)), \
REGS_SEGV_IS_FIXABLE(&r->skas))
#define UPT_FAULT_ADDR(r) \
__CHOOSE_MODE(SC_FAULT_ADDR(UPT_SC(r)), REGS_FAULT_ADDR(&r->skas))
#define UPT_FAULT_WRITE(r) \
CHOOSE_MODE(SC_FAULT_WRITE(UPT_SC(r)), REGS_FAULT_WRITE(&r->skas))
#define UPT_TRAP(r) __CHOOSE_MODE(SC_TRAP_TYPE(UPT_SC(r)), REGS_TRAP(&r->skas))
#define UPT_ERR(r) __CHOOSE_MODE(SC_FAULT_TYPE(UPT_SC(r)), REGS_ERR(&r->skas))
#define UPT_FAULTINFO(r) \
CHOOSE_MODE((&(r)->tt.faultinfo), (&(r)->skas.faultinfo))
#endif

15
arch/um/include/sysdep-x86_64/sigcontext.h
View file

@ -17,11 +17,12 @@
#define SC_FAULT_ADDR(sc) SC_CR2(sc)
#define SC_FAULT_TYPE(sc) SC_ERR(sc)
#define FAULT_WRITE(err) ((err) & 2)
#define SC_FAULT_WRITE(sc) FAULT_WRITE(SC_FAULT_TYPE(sc))
#define SC_TRAP_TYPE(sc) SC_TRAPNO(sc)
#define GET_FAULTINFO_FROM_SC(fi,sc) \
{ \
(fi).cr2 = SC_CR2(sc); \
(fi).error_code = SC_ERR(sc); \
(fi).trap_no = SC_TRAPNO(sc); \
}
/* ptrace expects that, at the start of a system call, %eax contains
* -ENOSYS, so this makes it so.
@ -29,8 +30,8 @@
#define SC_START_SYSCALL(sc) do SC_RAX(sc) = -ENOSYS; while(0)
#define SEGV_IS_FIXABLE(trap) ((trap) == 14)
#define SC_SEGV_IS_FIXABLE(sc) SEGV_IS_FIXABLE(SC_TRAP_TYPE(sc))
/* This is Page Fault */
#define SEGV_IS_FIXABLE(fi) ((fi)->trap_no == 14)
extern unsigned long *sc_sigmask(void *sc_ptr);

22
arch/um/include/sysdep-x86_64/skas_ptrace.h Normal file
View file

@ -0,0 +1,22 @@
/*
* Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
* Licensed under the GPL
*/
#ifndef __SYSDEP_X86_64_SKAS_PTRACE_H
#define __SYSDEP_X86_64_SKAS_PTRACE_H
struct ptrace_faultinfo {
int is_write;
unsigned long addr;
};
struct ptrace_ldt {
int func;
void *ptr;
unsigned long bytecount;
};
#define PTRACE_LDT 54
#endif

16
arch/um/kernel/ptrace.c
View file

@ -252,13 +252,13 @@ long sys_ptrace(long request, long pid, long addr, long data)
break;
#endif
case PTRACE_FAULTINFO: {
struct ptrace_faultinfo fault;
fault = ((struct ptrace_faultinfo)
{ .is_write = child->thread.err,
.addr = child->thread.cr2 });
ret = copy_to_user((unsigned long __user *) data, &fault,
sizeof(fault));
/* Take the info from thread->arch->faultinfo,
* but transfer max. sizeof(struct ptrace_faultinfo).
* On i386, ptrace_faultinfo is smaller!
*/
ret = copy_to_user((unsigned long __user *) data,
&child->thread.arch.faultinfo,
sizeof(struct ptrace_faultinfo));
if(ret)
break;
break;
@ -269,6 +269,7 @@ long sys_ptrace(long request, long pid, long addr, long data)
sizeof(child->pending.signal));
break;
#ifdef PTRACE_LDT
case PTRACE_LDT: {
struct ptrace_ldt ldt;
@ -284,6 +285,7 @@ long sys_ptrace(long request, long pid, long addr, long data)
ret = -EIO;
break;
}
#endif
#ifdef CONFIG_PROC_MM
case PTRACE_SWITCH_MM: {
struct mm_struct *old = child->mm;

3
arch/um/kernel/skas/include/skas.h
View file

@ -27,9 +27,10 @@ extern void map(int fd, unsigned long virt, unsigned long len, int r, int w,
extern int unmap(int fd, void *addr, unsigned long len);
extern int protect(int fd, unsigned long addr, unsigned long len,
int r, int w, int x);
extern void user_signal(int sig, union uml_pt_regs *regs);
extern void user_signal(int sig, union uml_pt_regs *regs, int pid);
extern int new_mm(int from);
extern void start_userspace(int cpu);
extern void get_skas_faultinfo(int pid, struct faultinfo * fi);
extern long execute_syscall_skas(void *r);
#endif

26
arch/um/kernel/skas/process.c
View file

@ -4,6 +4,7 @@
*/
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <signal.h>
@ -37,17 +38,26 @@ int is_skas_winch(int pid, int fd, void *data)
return(1);
}
static void handle_segv(int pid)
void get_skas_faultinfo(int pid, struct faultinfo * fi)
{
struct ptrace_faultinfo fault;
int err;
err = ptrace(PTRACE_FAULTINFO, pid, 0, &fault);
err = ptrace(PTRACE_FAULTINFO, pid, 0, fi);
if(err)
panic("handle_segv - PTRACE_FAULTINFO failed, errno = %d\n",
errno);
panic("get_skas_faultinfo - PTRACE_FAULTINFO failed, "
"errno = %d\n", errno);
segv(fault.addr, 0, FAULT_WRITE(fault.is_write), 1, NULL);
/* Special handling for i386, which has different structs */
if (sizeof(struct ptrace_faultinfo) < sizeof(struct faultinfo))
memset((char *)fi + sizeof(struct ptrace_faultinfo), 0,
sizeof(struct faultinfo) -
sizeof(struct ptrace_faultinfo));
}
static void handle_segv(int pid, union uml_pt_regs * regs)
{
get_skas_faultinfo(pid, &regs->skas.faultinfo);
segv(regs->skas.faultinfo, 0, 1, NULL);
}
/*To use the same value of using_sysemu as the caller, ask it that value (in local_using_sysemu)*/
@ -163,7 +173,7 @@ void userspace(union uml_pt_regs *regs)
if(WIFSTOPPED(status)){
switch(WSTOPSIG(status)){
case SIGSEGV:
handle_segv(pid);
handle_segv(pid, regs);
break;
case SIGTRAP + 0x80:
handle_trap(pid, regs, local_using_sysemu);
@ -177,7 +187,7 @@ void userspace(union uml_pt_regs *regs)
case SIGBUS:
case SIGFPE:
case SIGWINCH:
user_signal(WSTOPSIG(status), regs);
user_signal(WSTOPSIG(status), regs, pid);
break;
default:
printk("userspace - child stopped with signal "

24
arch/um/kernel/skas/trap_user.c
View file

@ -5,12 +5,15 @@
#include <signal.h>
#include <errno.h>
#include "sysdep/ptrace.h"
#include "signal_user.h"
#include "user_util.h"
#include "kern_util.h"
#include "task.h"
#include "sigcontext.h"
#include "skas.h"
#include "ptrace_user.h"
#include "sysdep/ptrace.h"
#include "sysdep/ptrace_user.h"
void sig_handler_common_skas(int sig, void *sc_ptr)
{
@ -31,9 +34,11 @@ void sig_handler_common_skas(int sig, void *sc_ptr)
r = &TASK_REGS(get_current())->skas;
save_user = r->is_user;
r->is_user = 0;
r->fault_addr = SC_FAULT_ADDR(sc);
r->fault_type = SC_FAULT_TYPE(sc);
r->trap_type = SC_TRAP_TYPE(sc);
if ( sig == SIGFPE || sig == SIGSEGV ||
sig == SIGBUS || sig == SIGILL ||
sig == SIGTRAP ) {
GET_FAULTINFO_FROM_SC(r->faultinfo, sc);
}
change_sig(SIGUSR1, 1);
info = &sig_info[sig];
@ -45,14 +50,17 @@ void sig_handler_common_skas(int sig, void *sc_ptr)
r->is_user = save_user;
}
void user_signal(int sig, union uml_pt_regs *regs)
extern int ptrace_faultinfo;
void user_signal(int sig, union uml_pt_regs *regs, int pid)
{
struct signal_info *info;
int segv = ((sig == SIGFPE) || (sig == SIGSEGV) || (sig == SIGBUS) ||
(sig == SIGILL) || (sig == SIGTRAP));
regs->skas.is_user = 1;
regs->skas.fault_addr = 0;
regs->skas.fault_type = 0;
regs->skas.trap_type = 0;
if (segv)
get_skas_faultinfo(pid, &regs->skas.faultinfo);
info = &sig_info[sig];
(*info->handler)(sig, regs);

25
arch/um/kernel/trap_kern.c
View file

@ -133,12 +133,19 @@ static int check_remapped_addr(unsigned long address, int is_write)
return(0);
}
unsigned long segv(unsigned long address, unsigned long ip, int is_write,
int is_user, void *sc)
/*
* We give a *copy* of the faultinfo in the regs to segv.
* This must be done, since nesting SEGVs could overwrite
* the info in the regs. A pointer to the info then would
* give us bad data!
*/
unsigned long segv(struct faultinfo fi, unsigned long ip, int is_user, void *sc)
{
struct siginfo si;
void *catcher;
int err;
int is_write = FAULT_WRITE(fi);
unsigned long address = FAULT_ADDRESS(fi);
if(!is_user && (address >= start_vm) && (address < end_vm)){
flush_tlb_kernel_vm();
@ -159,7 +166,7 @@ unsigned long segv(unsigned long address, unsigned long ip, int is_write,
}
else if(current->thread.fault_addr != NULL)
panic("fault_addr set but no fault catcher");
else if(arch_fixup(ip, sc))
else if(!is_user && arch_fixup(ip, sc))
return(0);
if(!is_user)
@ -171,6 +178,7 @@ unsigned long segv(unsigned long address, unsigned long ip, int is_write,
si.si_errno = 0;
si.si_code = BUS_ADRERR;
si.si_addr = (void *)address;
current->thread.arch.faultinfo = fi;
force_sig_info(SIGBUS, &si, current);
}
else if(err == -ENOMEM){
@ -180,22 +188,20 @@ unsigned long segv(unsigned long address, unsigned long ip, int is_write,
else {
si.si_signo = SIGSEGV;
si.si_addr = (void *) address;
current->thread.cr2 = address;
current->thread.err = is_write;
current->thread.arch.faultinfo = fi;
force_sig_info(SIGSEGV, &si, current);
}
return(0);
}
void bad_segv(unsigned long address, unsigned long ip, int is_write)
void bad_segv(struct faultinfo fi, unsigned long ip)
{
struct siginfo si;
si.si_signo = SIGSEGV;
si.si_code = SEGV_ACCERR;
si.si_addr = (void *) address;
current->thread.cr2 = address;
current->thread.err = is_write;
si.si_addr = (void *) FAULT_ADDRESS(fi);
current->thread.arch.faultinfo = fi;
force_sig_info(SIGSEGV, &si, current);
}
@ -204,6 +210,7 @@ void relay_signal(int sig, union uml_pt_regs *regs)
if(arch_handle_signal(sig, regs)) return;
if(!UPT_IS_USER(regs))
panic("Kernel mode signal %d", sig);
current->thread.arch.faultinfo = *UPT_FAULTINFO(regs);
force_sig(sig, current);
}

13
arch/um/kernel/trap_user.c
View file

@ -54,23 +54,22 @@ struct {
void segv_handler(int sig, union uml_pt_regs *regs)
{
int index, max;
struct faultinfo * fi = UPT_FAULTINFO(regs);
if(UPT_IS_USER(regs) && !UPT_SEGV_IS_FIXABLE(regs)){
bad_segv(UPT_FAULT_ADDR(regs), UPT_IP(regs),
UPT_FAULT_WRITE(regs));
if(UPT_IS_USER(regs) && !SEGV_IS_FIXABLE(fi)){
bad_segv(*fi, UPT_IP(regs));
return;
}
max = sizeof(segfault_record)/sizeof(segfault_record[0]);
index = next_trap_index(max);
nsegfaults++;
segfault_record[index].address = UPT_FAULT_ADDR(regs);
segfault_record[index].address = FAULT_ADDRESS(*fi);
segfault_record[index].pid = os_getpid();
segfault_record[index].is_write = UPT_FAULT_WRITE(regs);
segfault_record[index].is_write = FAULT_WRITE(*fi);
segfault_record[index].sp = UPT_SP(regs);
segfault_record[index].is_user = UPT_IS_USER(regs);
segv(UPT_FAULT_ADDR(regs), UPT_IP(regs), UPT_FAULT_WRITE(regs),
UPT_IS_USER(regs), regs);
segv(*fi, UPT_IP(regs), UPT_IS_USER(regs), regs);
}
void usr2_handler(int sig, union uml_pt_regs *regs)

4
arch/um/kernel/tt/tracer.c
View file

@ -89,8 +89,10 @@ void tracer_panic(char *format, ...)
static void tracer_segv(int sig, struct sigcontext sc)
{
struct faultinfo fi;
GET_FAULTINFO_FROM_SC(fi, &sc);
printf("Tracing thread segfault at address 0x%lx, ip 0x%lx\n",
SC_FAULT_ADDR(&sc), SC_IP(&sc));
FAULT_ADDRESS(fi), SC_IP(&sc));
while(1)
pause();
}

6
arch/um/kernel/tt/trap_user.c
View file

@ -7,6 +7,7 @@
#include <errno.h>
#include <signal.h>
#include "sysdep/ptrace.h"
#include "sysdep/sigcontext.h"
#include "signal_user.h"
#include "user_util.h"
#include "kern_util.h"
@ -28,6 +29,11 @@ void sig_handler_common_tt(int sig, void *sc_ptr)
change_sig(SIGSEGV, 1);
r = &TASK_REGS(get_current())->tt;
if ( sig == SIGFPE || sig == SIGSEGV ||
sig == SIGBUS || sig == SIGILL ||
sig == SIGTRAP ) {
GET_FAULTINFO_FROM_SC(r->faultinfo, sc);
}
save_regs = *r;
is_user = user_context(SC_SP(sc));
r->sc = sc;

17
arch/um/sys-i386/signal.c
View file

@ -47,9 +47,6 @@ static int copy_sc_from_user_skas(struct pt_regs *regs,
REGS_CS(regs->regs.skas.regs) = sc.cs;
REGS_EFLAGS(regs->regs.skas.regs) = sc.eflags;
REGS_SS(regs->regs.skas.regs) = sc.ss;
regs->regs.skas.fault_addr = sc.cr2;
regs->regs.skas.fault_type = FAULT_WRITE(sc.err);
regs->regs.skas.trap_type = sc.trapno;
err = restore_fp_registers(userspace_pid[0], fpregs);
if(err < 0){
@ -62,11 +59,11 @@ static int copy_sc_from_user_skas(struct pt_regs *regs,
}
int copy_sc_to_user_skas(struct sigcontext *to, struct _fpstate *to_fp,
struct pt_regs *regs, unsigned long fault_addr,
int fault_type)
struct pt_regs *regs)
{
struct sigcontext sc;
unsigned long fpregs[HOST_FP_SIZE];
struct faultinfo * fi = &current->thread.arch.faultinfo;
int err;
sc.gs = REGS_GS(regs->regs.skas.regs);
@ -86,9 +83,9 @@ int copy_sc_to_user_skas(struct sigcontext *to, struct _fpstate *to_fp,
sc.eflags = REGS_EFLAGS(regs->regs.skas.regs);
sc.esp_at_signal = regs->regs.skas.regs[UESP];
sc.ss = regs->regs.skas.regs[SS];
sc.cr2 = fault_addr;
sc.err = TO_SC_ERR(fault_type);
sc.trapno = regs->regs.skas.trap_type;
sc.cr2 = fi->cr2;
sc.err = fi->error_code;
sc.trapno = fi->trap_no;
err = save_fp_registers(userspace_pid[0], fpregs);
if(err < 0){
@ -167,9 +164,7 @@ static int copy_sc_to_user(struct sigcontext *to, struct _fpstate *fp,
{
return(CHOOSE_MODE(copy_sc_to_user_tt(to, fp, UPT_SC(&from->regs),
sizeof(*fp)),
copy_sc_to_user_skas(to, fp, from,
current->thread.cr2,
current->thread.err)));
copy_sc_to_user_skas(to, fp, from)));
}
static int copy_ucontext_to_user(struct ucontext *uc, struct _fpstate *fp,

10
arch/um/sys-x86_64/signal.c
View file

@ -57,7 +57,7 @@ static int copy_sc_from_user_skas(struct pt_regs *regs,
int copy_sc_to_user_skas(struct sigcontext *to, struct _fpstate *to_fp,
struct pt_regs *regs, unsigned long mask)
{
unsigned long eflags;
struct faultinfo * fi = &current->thread.arch.faultinfo;
int err = 0;
err |= __put_user(0, &to->gs);
@ -84,14 +84,16 @@ int copy_sc_to_user_skas(struct sigcontext *to, struct _fpstate *to_fp,
err |= PUTREG(regs, R14, to, r14);
err |= PUTREG(regs, R15, to, r15);
err |= PUTREG(regs, CS, to, cs); /* XXX x86_64 doesn't do this */
err |= __put_user(current->thread.err, &to->err);
err |= __put_user(current->thread.trap_no, &to->trapno);
err |= __put_user(fi->cr2, &to->cr2);
err |= __put_user(fi->error_code, &to->err);
err |= __put_user(fi->trap_no, &to->trapno);
err |= PUTREG(regs, RIP, to, rip);
err |= PUTREG(regs, EFLAGS, to, eflags);
#undef PUTREG
err |= __put_user(mask, &to->oldmask);
err |= __put_user(current->thread.cr2, &to->cr2);
return(err);
}

5
include/asm-um/processor-generic.h
View file

@ -24,9 +24,6 @@ struct thread_struct {
int forking;
int nsyscalls;
struct pt_regs regs;
unsigned long cr2;
int err;
unsigned long trap_no;
int singlestep_syscall;
void *fault_addr;
void *fault_catcher;
@ -74,8 +71,6 @@ struct thread_struct {
.forking = 0, \
.nsyscalls = 0, \
.regs = EMPTY_REGS, \
.cr2 = 0, \
.err = 0, \
.fault_addr = NULL, \
.prev_sched = NULL, \
.temp_stack = 0, \

7
include/asm-um/processor-i386.h
View file

@ -9,13 +9,18 @@
extern int host_has_xmm;
extern int host_has_cmov;
/* include faultinfo structure */
#include "sysdep/faultinfo.h"
struct arch_thread {
unsigned long debugregs[8];
int debugregs_seq;
struct faultinfo faultinfo;
};
#define INIT_ARCH_THREAD { .debugregs = { [ 0 ... 7 ] = 0 }, \
.debugregs_seq = 0 }
.debugregs_seq = 0, \
.faultinfo = { 0, 0, 0 } }
#include "asm/arch/user.h"

12
include/asm-um/processor-x86_64.h
View file

@ -7,9 +7,13 @@
#ifndef __UM_PROCESSOR_X86_64_H
#define __UM_PROCESSOR_X86_64_H
#include "asm/arch/user.h"
/* include faultinfo structure */
#include "sysdep/faultinfo.h"
struct arch_thread {
unsigned long debugregs[8];
int debugregs_seq;
struct faultinfo faultinfo;
};
/* REP NOP (PAUSE) is a good thing to insert into busy-wait loops. */
@ -20,7 +24,11 @@ extern inline void rep_nop(void)
#define cpu_relax() rep_nop()
#define INIT_ARCH_THREAD { }
#define INIT_ARCH_THREAD { .debugregs = { [ 0 ... 7 ] = 0 }, \
.debugregs_seq = 0, \
.faultinfo = { 0, 0, 0 } }
#include "asm/arch/user.h"
#define current_text_addr() \
({ void *pc; __asm__("movq $1f,%0\n1:":"=g" (pc)); pc; })