[PATCH] uml: Improve SIGBUS diagnostics
UML can get a SIGBUS anywhere if the tmpfs mount being used for its memory
runs out of space. This patch adds a printk before the panic to provide a
clue as to what likely went wrong.
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/arch/um/kernel/trap.c b/arch/um/kernel/trap.c
index ac70fa5..e5eeaf2 100644
--- a/arch/um/kernel/trap.c
+++ b/arch/um/kernel/trap.c
@@ -227,9 +227,16 @@
void relay_signal(int sig, union uml_pt_regs *regs)
{
- if(arch_handle_signal(sig, regs)) return;
- if(!UPT_IS_USER(regs))
+ if(arch_handle_signal(sig, regs))
+ return;
+
+ if(!UPT_IS_USER(regs)){
+ if(sig == SIGBUS)
+ printk("Bus error - the /dev/shm or /tmp mount likely "
+ "just ran out of space\n");
panic("Kernel mode signal %d", sig);
+ }
+
current->thread.arch.faultinfo = *UPT_FAULTINFO(regs);
force_sig(sig, current);
}