linux-stable/arch/um/sys-i386/stub_segv.c
Jeff Dike fb30d64568 [PATCH] uml: add missing __volatile__
We were missing __volatile__ on some bits of asm in the segfault handlers.
On x86_64, this was messing up the move from %rdx to uc because that was
moved to after the GET_FAULTINFO_FROM_SC, which changed %rdx.

Also changed the other bit of asm and the one in the i386 handler to
prevent any similar occurrences.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-04-19 09:13:51 -07:00

32 lines
889 B
C

/*
* Copyright (C) 2004 Jeff Dike (jdike@addtoit.com)
* Licensed under the GPL
*/
#include <signal.h>
#include <sys/select.h> /* The only way I can see to get sigset_t */
#include <asm/unistd.h>
#include "uml-config.h"
#include "sysdep/stub.h"
#include "sysdep/sigcontext.h"
#include "sysdep/faultinfo.h"
void __attribute__ ((__section__ (".__syscall_stub")))
stub_segv_handler(int sig)
{
struct sigcontext *sc = (struct sigcontext *) (&sig + 1);
int pid;
GET_FAULTINFO_FROM_SC(*((struct faultinfo *) UML_CONFIG_STUB_DATA),
sc);
pid = stub_syscall0(__NR_getpid);
stub_syscall2(__NR_kill, pid, SIGUSR1);
/* Load pointer to sigcontext into esp, since we need to leave
* the stack in its original form when we do the sigreturn here, by
* hand.
*/
__asm__ __volatile__("mov %0,%%esp ; movl %1, %%eax ; "
"int $0x80" : : "a" (sc), "g" (__NR_sigreturn));
}