commit 953206858070e5921b9d5931c293ec983a6790cb
author Jeff Dike <jdike@addtoit.com> Mon Nov 07 00:58:45 2005 -0800
committer Linus Torvalds <torvalds@g5.osdl.org> Mon Nov 07 07:53:30 2005 -0800
tree 9caf1d094ee6f001856d5c433b3c60f309c9da98
parent d9b5444eeb3a663ca4a625878b1421c9e9b18e8b

[PATCH] uml: improve stub debugging

Add some more debugging information when a stub does something unexpected,
usually segfaulting.  Now, it dumps out the stub's registers as well as the
signal.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

arch/um/kernel/skas/process.c

diff --git a/arch/um/kernel/skas/process.c b/arch/um/kernel/skas/process.c
index 5cd0e99..42f2da6 100644
--- a/arch/um/kernel/skas/process.c
+++ b/arch/um/kernel/skas/process.c
@@ -69,6 +69,17 @@
 
         if((n < 0) || !WIFSTOPPED(status) ||
            (WSTOPSIG(status) != SIGUSR1 && WSTOPSIG(status) != SIGTRAP)){
+		unsigned long regs[FRAME_SIZE];
+		if(ptrace(PTRACE_GETREGS, pid, 0, regs) < 0)
+			printk("Failed to get registers from stub, "
+			       "errno = %d\n", errno);
+		else {
+			int i;
+
+			printk("Stub registers -\n");
+			for(i = 0; i < FRAME_SIZE; i++)
+				printk("\t%d - %lx\n", i, regs[i]);
+		}
                 panic("%s : failed to wait for SIGUSR1/SIGTRAP, "
                       "pid = %d, n = %d, errno = %d, status = 0x%x\n",
                       fname, pid, n, errno, status);