um: Add kerneldoc for segv_handler

Signed-off-by: Thomas Meyer <thomas@m3y3r.de>
Signed-off-by: Richard Weinberger <richard@nod.at>

1 files changed, 10 insertions, 0 deletions

diff --git a/arch/um/kernel/trap.c b/arch/um/kernel/trap.c
index 59158871b9fc..4e6fcb32620f 100644
--- a/arch/um/kernel/trap.c
+++ b/arch/um/kernel/trap.c
@@ -183,6 +183,16 @@ void fatal_sigsegv(void)
         os_dump_core();
 }
 
+/**
+ * segv_handler() - the SIGSEGV handler
+ * @sig:        the signal number
+ * @unused_si:  the signal info struct; unused in this handler
+ * @regs:       the ptrace register information
+ *
+ * The handler first extracts the faultinfo from the UML ptrace regs struct.
+ * If the userfault did not happen in an UML userspace process, bad_segv is called.
+ * Otherwise the signal did happen in a cloned userspace process, handle it.
+ */
 void segv_handler(int sig, struct siginfo *unused_si, struct uml_pt_regs *regs)
 {
         struct faultinfo * fi = UPT_FAULTINFO(regs);