diff options
| author | Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> | 2005-09-30 11:58:59 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2005-09-30 12:41:18 -0700 |
| commit | be662a18b7763496a052d489206af9ca2c2e1ac2 (patch) | |
| tree | 73b0777d900e2f6b10642acd1e6a0d8017cc61e8 /arch/um | |
| parent | 79dfa4a5a2eea5035de793b1633031750fe8d3ff (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>
Diffstat (limited to 'arch/um')
| -rw-r--r-- | arch/um/include/sysdep-i386/sigcontext.h | 10 | ||||
| -rw-r--r-- | arch/um/include/sysdep-x86_64/sigcontext.h | 5 | ||||
| -rw-r--r-- | arch/um/kernel/trap_kern.c | 5 |
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 1fe72926516..23fd2644d7e 100644 --- a/arch/um/include/sysdep-i386/sigcontext.h +++ b/arch/um/include/sysdep-i386/sigcontext.h @@ -6,6 +6,7 @@ #ifndef __SYS_SIGCONTEXT_I386_H #define __SYS_SIGCONTEXT_I386_H +#include "uml-config.h" #include <sysdep/sc.h> #define IP_RESTART_SYSCALL(ip) ((ip) -= 2) @@ -26,7 +27,14 @@ #define SC_START_SYSCALL(sc) do SC_EAX(sc) = -ENOSYS; while(0) /* This is Page Fault */ -#define SEGV_IS_FIXABLE(fi) ((fi)->trap_no == 14) +#define SEGV_IS_FIXABLE(fi) ((fi)->trap_no == 14) + +/* SKAS3 has no trap_no on i386, but get_skas_faultinfo() sets it to 0. */ +#ifdef UML_CONFIG_MODE_SKAS +#define SEGV_MAYBE_FIXABLE(fi) ((fi)->trap_no == 0 && ptrace_faultinfo) +#else +#define SEGV_MAYBE_FIXABLE(fi) 0 +#endif extern unsigned long *sc_sigmask(void *sc_ptr); extern 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 2a78260d15a..41073235e7a 100644 --- a/arch/um/include/sysdep-x86_64/sigcontext.h +++ b/arch/um/include/sysdep-x86_64/sigcontext.h @@ -31,7 +31,10 @@ #define SC_START_SYSCALL(sc) do SC_RAX(sc) = -ENOSYS; while(0) /* This is Page Fault */ -#define SEGV_IS_FIXABLE(fi) ((fi)->trap_no == 14) +#define SEGV_IS_FIXABLE(fi) ((fi)->trap_no == 14) + +/* No broken SKAS API, which doesn't pass trap_no, here. */ +#define SEGV_MAYBE_FIXABLE(fi) 0 extern unsigned long *sc_sigmask(void *sc_ptr); diff --git a/arch/um/kernel/trap_kern.c b/arch/um/kernel/trap_kern.c index d297429ac36..95c8f8733ba 100644 --- a/arch/um/kernel/trap_kern.c +++ b/arch/um/kernel/trap_kern.c @@ -26,6 +26,9 @@ #include "mconsole_kern.h" #include "mem.h" #include "mem_kern.h" +#ifdef CONFIG_MODE_SKAS +#include "skas.h" +#endif /* Note this is constrained to return 0, -EFAULT, -EACCESS, -ENOMEM by segv(). */ int 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) else if(current->mm == NULL) panic("Segfault with no mm"); - if (SEGV_IS_FIXABLE(&fi)) + if (SEGV_IS_FIXABLE(&fi) || SEGV_MAYBE_FIXABLE(&fi)) err = handle_page_fault(address, ip, is_write, is_user, &si.si_code); else { err = -EFAULT; |