From 7adae99faaf01c3555e90a75d5222275d6299ffd Mon Sep 17 00:00:00 2001
From: Andi Kleen <ak@suse.de>
Date: Mon, 12 Sep 2005 18:49:24 +0200
Subject: [PATCH] --- yaml --- r: 8588 b: refs/heads/master c:
 673242c10d535bfe238d9d8e82ac93432d35b88e h: refs/heads/master v: v3

---
 [refs]                         |  2 +-
 trunk/arch/x86_64/kernel/mce.c | 32 +++++++++++++++++++++-----------
 2 files changed, 22 insertions(+), 12 deletions(-)

diff --git a/[refs] b/[refs]
index 0baea7aaa602..f81fa11d657c 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: a54e678b8f476d6f28e6aa4409f6b88ce476af1b
+refs/heads/master: 673242c10d535bfe238d9d8e82ac93432d35b88e
diff --git a/trunk/arch/x86_64/kernel/mce.c b/trunk/arch/x86_64/kernel/mce.c
index 8aa56736cde3..87ea8fdd43fd 100644
--- a/trunk/arch/x86_64/kernel/mce.c
+++ b/trunk/arch/x86_64/kernel/mce.c
@@ -56,15 +56,19 @@ void mce_log(struct mce *mce)
 	smp_wmb();
 	for (;;) {
 		entry = rcu_dereference(mcelog.next);
-		/* When the buffer fills up discard new entries. Assume 
-		   that the earlier errors are the more interesting. */
-		if (entry >= MCE_LOG_LEN) {
-			set_bit(MCE_OVERFLOW, &mcelog.flags);
-			return;
+		for (;;) {
+			/* When the buffer fills up discard new entries. Assume
+			   that the earlier errors are the more interesting. */
+			if (entry >= MCE_LOG_LEN) {
+				set_bit(MCE_OVERFLOW, &mcelog.flags);
+				return;
+			}
+			/* Old left over entry. Skip. */
+			if (mcelog.entry[entry].finished) {
+				entry++;
+				continue;
+			}
 		}
-		/* Old left over entry. Skip. */
-		if (mcelog.entry[entry].finished)
-			continue;
 		smp_rmb();
 		next = entry + 1;
 		if (cmpxchg(&mcelog.next, entry, next) == entry)
@@ -404,9 +408,15 @@ static ssize_t mce_read(struct file *filp, char __user *ubuf, size_t usize, loff
 	}
 
 	err = 0;
-	for (i = 0; i < next; i++) {
-		if (!mcelog.entry[i].finished)
-			continue;
+	for (i = 0; i < next; i++) {		
+		unsigned long start = jiffies;
+		while (!mcelog.entry[i].finished) {
+			if (!time_before(jiffies, start + 2)) {
+				memset(mcelog.entry + i,0, sizeof(struct mce));
+				continue;
+			}
+			cpu_relax();
+		}
 		smp_rmb();
 		err |= copy_to_user(buf, mcelog.entry + i, sizeof(struct mce));
 		buf += sizeof(struct mce);