aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorPaolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>2005-09-30 14:58:59 -0400
committerLinus Torvalds <torvalds@g5.osdl.org>2005-09-30 15:41:18 -0400
commitbe662a18b7763496a052d489206af9ca2c2e1ac2 (patch)
tree73b0777d900e2f6b10642acd1e6a0d8017cc61e8
parent79dfa4a5a2eea5035de793b1633031750fe8d3ff (diff)
[PATCH] uml: fix page faults in SKAS3 mode.
I hadn't been running a SKAS3 host when testing the "uml: fix hang in TT mode on fault" patch (commit 546fe1cbf91d4d62e3849517c31a2327c992e5c5), and I didn't think enough to the missing trap_no in SKAS3 mode. In fact, the resulting kernel doesn't work at all in SKAS3 mode. Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
-rw-r--r--arch/um/include/sysdep-i386/sigcontext.h10
-rw-r--r--arch/um/include/sysdep-x86_64/sigcontext.h5
-rw-r--r--arch/um/kernel/trap_kern.c5
3 files changed, 17 insertions, 3 deletions
diff --git a/arch/um/include/sysdep-i386/sigcontext.h b/arch/um/include/sysdep-i386/sigcontext.h
index 1fe729265167..23fd2644d7ed 100644
--- a/arch/um/include/sysdep-i386/sigcontext.h
+++ b/arch/um/include/sysdep-i386/sigcontext.h
@@ -6,6 +6,7 @@
6#ifndef __SYS_SIGCONTEXT_I386_H 6#ifndef __SYS_SIGCONTEXT_I386_H
7#define __SYS_SIGCONTEXT_I386_H 7#define __SYS_SIGCONTEXT_I386_H
8 8
9#include "uml-config.h"
9#include <sysdep/sc.h> 10#include <sysdep/sc.h>
10 11
11#define IP_RESTART_SYSCALL(ip) ((ip) -= 2) 12#define IP_RESTART_SYSCALL(ip) ((ip) -= 2)
@@ -26,7 +27,14 @@
26#define SC_START_SYSCALL(sc) do SC_EAX(sc) = -ENOSYS; while(0) 27#define SC_START_SYSCALL(sc) do SC_EAX(sc) = -ENOSYS; while(0)
27 28
28/* This is Page Fault */ 29/* This is Page Fault */
29#define SEGV_IS_FIXABLE(fi) ((fi)->trap_no == 14) 30#define SEGV_IS_FIXABLE(fi) ((fi)->trap_no == 14)
31
32/* SKAS3 has no trap_no on i386, but get_skas_faultinfo() sets it to 0. */
33#ifdef UML_CONFIG_MODE_SKAS
34#define SEGV_MAYBE_FIXABLE(fi) ((fi)->trap_no == 0 && ptrace_faultinfo)
35#else
36#define SEGV_MAYBE_FIXABLE(fi) 0
37#endif
30 38
31extern unsigned long *sc_sigmask(void *sc_ptr); 39extern unsigned long *sc_sigmask(void *sc_ptr);
32extern int sc_get_fpregs(unsigned long buf, void *sc_ptr); 40extern int sc_get_fpregs(unsigned long buf, void *sc_ptr);
diff --git a/arch/um/include/sysdep-x86_64/sigcontext.h b/arch/um/include/sysdep-x86_64/sigcontext.h
index 2a78260d15a0..41073235e7ad 100644
--- a/arch/um/include/sysdep-x86_64/sigcontext.h
+++ b/arch/um/include/sysdep-x86_64/sigcontext.h
@@ -31,7 +31,10 @@
31#define SC_START_SYSCALL(sc) do SC_RAX(sc) = -ENOSYS; while(0) 31#define SC_START_SYSCALL(sc) do SC_RAX(sc) = -ENOSYS; while(0)
32 32
33/* This is Page Fault */ 33/* This is Page Fault */
34#define SEGV_IS_FIXABLE(fi) ((fi)->trap_no == 14) 34#define SEGV_IS_FIXABLE(fi) ((fi)->trap_no == 14)
35
36/* No broken SKAS API, which doesn't pass trap_no, here. */
37#define SEGV_MAYBE_FIXABLE(fi) 0
35 38
36extern unsigned long *sc_sigmask(void *sc_ptr); 39extern unsigned long *sc_sigmask(void *sc_ptr);
37 40
diff --git a/arch/um/kernel/trap_kern.c b/arch/um/kernel/trap_kern.c
index d297429ac360..95c8f8733baf 100644
--- a/arch/um/kernel/trap_kern.c
+++ b/arch/um/kernel/trap_kern.c
@@ -26,6 +26,9 @@
26#include "mconsole_kern.h" 26#include "mconsole_kern.h"
27#include "mem.h" 27#include "mem.h"
28#include "mem_kern.h" 28#include "mem_kern.h"
29#ifdef CONFIG_MODE_SKAS
30#include "skas.h"
31#endif
29 32
30/* Note this is constrained to return 0, -EFAULT, -EACCESS, -ENOMEM by segv(). */ 33/* Note this is constrained to return 0, -EFAULT, -EACCESS, -ENOMEM by segv(). */
31int handle_page_fault(unsigned long address, unsigned long ip, 34int handle_page_fault(unsigned long address, unsigned long ip,
@@ -134,7 +137,7 @@ unsigned long segv(struct faultinfo fi, unsigned long ip, int is_user, void *sc)
134 else if(current->mm == NULL) 137 else if(current->mm == NULL)
135 panic("Segfault with no mm"); 138 panic("Segfault with no mm");
136 139
137 if (SEGV_IS_FIXABLE(&fi)) 140 if (SEGV_IS_FIXABLE(&fi) || SEGV_MAYBE_FIXABLE(&fi))
138 err = handle_page_fault(address, ip, is_write, is_user, &si.si_code); 141 err = handle_page_fault(address, ip, is_write, is_user, &si.si_code);
139 else { 142 else {
140 err = -EFAULT; 143 err = -EFAULT;