[PATCH 2/3] x86_64: During VM oom condition, kill all threads in process group

During a VM oom condition, kill all threads in the process group.

We have had complaints where a threaded application is left in a bad state
after one of it's threads is killed when we hit a VM: out_of_memory
condition.

Killing just one of the process threads can leave the application in a
bad state, whereas killing the entire process group would
allow for the application to restart, or otherwise handled, and makes it
very obvious that something has gone wrong.

This change allows the entire process group to be taken down, rather than
just the one thread.

Signed-off-by: Will <redacted>
---

 arch/x86_64/mm/fault.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/arch/x86_64/mm/fault.c b/arch/x86_64/mm/fault.c
index 6ada723..328d504 100644
--- a/arch/x86_64/mm/fault.c
+++ b/arch/x86_64/mm/fault.c

@@ -563,7 +563,7 @@ out_of_memory:
 	}
 	printk("VM: killing process %s\n", tsk->comm);
 	if (error_code & 4)
-		do_exit(SIGKILL);
+		do_group_exit(SIGKILL);
 	goto no_context;
 
 do_sigbus: