From 377fad3acbb7e94ab9942a74e0d9ede8eeb2f039 Mon Sep 17 00:00:00 2001 From: Jeff Dike Date: Sun, 6 May 2007 14:51:25 -0700 Subject: 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 Cc: Paolo 'Blaisorblade' Giarrusso Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/um/kernel/trap.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) (limited to 'arch/um/kernel/trap.c') diff --git a/arch/um/kernel/trap.c b/arch/um/kernel/trap.c index c3e62e634c0..0c467fa0887 100644 --- a/arch/um/kernel/trap.c +++ b/arch/um/kernel/trap.c @@ -170,8 +170,10 @@ unsigned long segv(struct faultinfo fi, unsigned long ip, int is_user, flush_tlb_kernel_vm(); return 0; } - else if(current->mm == NULL) - panic("Segfault with no mm"); + else if(current->mm == NULL) { + show_regs(container_of(regs, struct pt_regs, regs)); + panic("Segfault with no mm"); + } if (SEGV_IS_FIXABLE(&fi) || SEGV_MAYBE_FIXABLE(&fi)) err = handle_page_fault(address, ip, is_write, is_user, &si.si_code); @@ -194,9 +196,11 @@ unsigned long segv(struct faultinfo fi, unsigned long ip, int is_user, else if(!is_user && arch_fixup(ip, regs)) return 0; - if(!is_user) + if(!is_user) { + show_regs(container_of(regs, struct pt_regs, regs)); panic("Kernel mode fault at addr 0x%lx, ip 0x%lx", address, ip); + } if (err == -EACCES) { si.si_signo = SIGBUS; -- cgit v1.2.3