diff options
| author | Jeff Dike <jdike@addtoit.com> | 2007-05-06 14:51:25 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-05-07 12:13:02 -0700 |
| commit | 377fad3acbb7e94ab9942a74e0d9ede8eeb2f039 (patch) | |
| tree | 0bf8046bb1fa6ccb51df76b56819dee6b6d7487b /arch/um/os-Linux | |
| parent | 5d86456d3852cb95a38d2b23fe01cede54984ba5 (diff) | |
uml: kernel segfaults should dump proper registers
If there's a segfault inside the kernel, we want a dump of the registers at
the point of the segfault, not the registers at the point of calling panic or
the last userspace registers.
sig_handler_common_skas now uses a static register set in the case of a
SIGSEGV to avoid messing up the process registers if the segfault turns out to
be non-fatal.
The architecture sigcontext-to-pt_regs copying code was repurposed to copy
data out of the SEGV stack frame.
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/um/os-Linux')
| -rw-r--r-- | arch/um/os-Linux/skas/trap.c | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/arch/um/os-Linux/skas/trap.c b/arch/um/os-Linux/skas/trap.c index 6a20d08caf91..5110eff51b90 100644 --- a/arch/um/os-Linux/skas/trap.c +++ b/arch/um/os-Linux/skas/trap.c @@ -15,6 +15,8 @@ #include "sysdep/ptrace_user.h" #include "os.h" +static union uml_pt_regs ksig_regs[UM_NR_CPUS]; + void sig_handler_common_skas(int sig, void *sc_ptr) { struct sigcontext *sc = sc_ptr; @@ -27,10 +29,19 @@ void sig_handler_common_skas(int sig, void *sc_ptr) * the process will die. * XXX Figure out why this is better than SA_NODEFER */ - if(sig == SIGSEGV) + if(sig == SIGSEGV) { change_sig(SIGSEGV, 1); + /* For segfaults, we want the data from the + * sigcontext. In this case, we don't want to mangle + * the process registers, so use a static set of + * registers. For other signals, the process + * registers are OK. + */ + r = &ksig_regs[cpu()]; + copy_sc(r, sc_ptr); + } + else r = TASK_REGS(get_current()); - r = TASK_REGS(get_current()); save_user = r->skas.is_user; r->skas.is_user = 0; if ( sig == SIGFPE || sig == SIGSEGV || |