From 09cf52ea0f371e16d0c6d016b4f403b3a45a747c Mon Sep 17 00:00:00 2001
From: Roland McGrath <roland@redhat.com>
Date: Tue, 4 Mar 2008 14:28:30 -0800
Subject: [PATCH] --- yaml --- r: 86781 b: refs/heads/master c:
 d31472b6d4f799a68d877f69b2f843eec5875472 h: refs/heads/master i:   86779:
 ea608679625c4879ad1b7935e171af30a8a4217a v: v3

---
 [refs]                |  2 +-
 trunk/fs/binfmt_elf.c | 15 +++++++++++++++
 2 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/[refs] b/[refs]
index 54d05625b523..2993da85a152 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 938a9204e0df070bfbaac71f6403cebed76763ad
+refs/heads/master: d31472b6d4f799a68d877f69b2f843eec5875472
diff --git a/trunk/fs/binfmt_elf.c b/trunk/fs/binfmt_elf.c
index 41a958a7585e..5e1a4fb5cacb 100644
--- a/trunk/fs/binfmt_elf.c
+++ b/trunk/fs/binfmt_elf.c
@@ -1424,6 +1424,18 @@ struct elf_note_info {
 	int thread_notes;
 };
 
+/*
+ * When a regset has a writeback hook, we call it on each thread before
+ * dumping user memory.  On register window machines, this makes sure the
+ * user memory backing the register data is up to date before we read it.
+ */
+static void do_thread_regset_writeback(struct task_struct *task,
+				       const struct user_regset *regset)
+{
+	if (regset->writeback)
+		regset->writeback(task, regset, 1);
+}
+
 static int fill_thread_core_info(struct elf_thread_core_info *t,
 				 const struct user_regset_view *view,
 				 long signr, size_t *total)
@@ -1445,6 +1457,8 @@ static int fill_thread_core_info(struct elf_thread_core_info *t,
 		  sizeof(t->prstatus), &t->prstatus);
 	*total += notesize(&t->notes[0]);
 
+	do_thread_regset_writeback(t->task, &view->regsets[0]);
+
 	/*
 	 * Each other regset might generate a note too.  For each regset
 	 * that has no core_note_type or is inactive, we leave t->notes[i]
@@ -1452,6 +1466,7 @@ static int fill_thread_core_info(struct elf_thread_core_info *t,
 	 */
 	for (i = 1; i < view->n; ++i) {
 		const struct user_regset *regset = &view->regsets[i];
+		do_thread_regset_writeback(t->task, regset);
 		if (regset->core_note_type &&
 		    (!regset->active || regset->active(t->task, regset))) {
 			int ret;