Merge tag 'kvm-s390-next-5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD

KVM: s390: Features and Enhancements for 5.7 part1

1. Allow to disable gisa
2. protected virtual machines
  Protected VMs (PVM) are KVM VMs, where KVM can't access the VM's
  state like guest memory and guest registers anymore. Instead the
  PVMs are mostly managed by a new entity called Ultravisor (UV),
  which provides an API, so KVM and the PV can request management
  actions.

  PVMs are encrypted at rest and protected from hypervisor access
  while running.  They switch from a normal operation into protected
  mode, so we can still use the standard boot process to load a
  encrypted blob and then move it into protected mode.

  Rebooting is only possible by passing through the unprotected/normal
  mode and switching to protected again.

  One mm related patch will go via Andrews mm tree ( mm/gup/writeback:
  add callbacks for inaccessible pages)

4 files changed, 31 insertions, 24 deletions

diff --git a/drivers/md/bcache/alloc.c b/drivers/md/bcache/alloc.c
index a1df0d95151c..8bc1faf71ff2 100644
--- a/drivers/md/bcache/alloc.c
+++ b/drivers/md/bcache/alloc.c
@@ -67,6 +67,7 @@
 #include <linux/blkdev.h>
 #include <linux/kthread.h>
 #include <linux/random.h>
+#include <linux/sched/signal.h>
 #include <trace/events/bcache.h>
 
 #define MAX_OPEN_BUCKETS 128
@@ -733,8 +734,21 @@ int bch_open_buckets_alloc(struct cache_set *c)
 
 int bch_cache_allocator_start(struct cache *ca)
 {
-	struct task_struct *k = kthread_run(bch_allocator_thread,
-					    ca, "bcache_allocator");
+	struct task_struct *k;
+
+	/*
+	 * In case previous btree check operation occupies too many
+	 * system memory for bcache btree node cache, and the
+	 * registering process is selected by OOM killer. Here just
+	 * ignore the SIGKILL sent by OOM killer if there is, to
+	 * avoid kthread_run() being failed by pending signals. The
+	 * bcache registering process will exit after the registration
+	 * done.
+	 */
+	if (signal_pending(current))
+		flush_signals(current);
+
+	k = kthread_run(bch_allocator_thread, ca, "bcache_allocator");
 	if (IS_ERR(k))
 		return PTR_ERR(k);
 
diff --git a/drivers/md/bcache/btree.c b/drivers/md/bcache/btree.c
index fa872df4e770..b12186c87f52 100644
--- a/drivers/md/bcache/btree.c
+++ b/drivers/md/bcache/btree.c
@@ -34,6 +34,7 @@
 #include <linux/random.h>
 #include <linux/rcupdate.h>
 #include <linux/sched/clock.h>
+#include <linux/sched/signal.h>
 #include <linux/rculist.h>
 #include <linux/delay.h>
 #include <trace/events/bcache.h>
@@ -1913,6 +1914,18 @@ static int bch_gc_thread(void *arg)
 
 int bch_gc_thread_start(struct cache_set *c)
 {
+	/*
+	 * In case previous btree check operation occupies too many
+	 * system memory for bcache btree node cache, and the
+	 * registering process is selected by OOM killer. Here just
+	 * ignore the SIGKILL sent by OOM killer if there is, to
+	 * avoid kthread_run() being failed by pending signals. The
+	 * bcache registering process will exit after the registration
+	 * done.
+	 */
+	if (signal_pending(current))
+		flush_signals(current);
+
 	c->gc_thread = kthread_run(bch_gc_thread, c, "bcache_gc");
 	return PTR_ERR_OR_ZERO(c->gc_thread);
 }
diff --git a/drivers/md/bcache/journal.c b/drivers/md/bcache/journal.c
index 6730820780b0..0e3ff9745ac7 100644
--- a/drivers/md/bcache/journal.c
+++ b/drivers/md/bcache/journal.c
@@ -417,8 +417,6 @@ err:
 
 /* Journalling */
 
-#define nr_to_fifo_front(p, front_p, mask)	(((p) - (front_p)) & (mask))
-
 static void btree_flush_write(struct cache_set *c)
 {
 	struct btree *b, *t, *btree_nodes[BTREE_FLUSH_NR];
@@ -510,9 +508,8 @@ static void btree_flush_write(struct cache_set *c)
 		 *   journal entry can be reclaimed). These selected nodes
 		 *   will be ignored and skipped in the folowing for-loop.
 		 */
-		if (nr_to_fifo_front(btree_current_write(b)->journal,
-				     fifo_front_p,
-				     mask) != 0) {
+		if (((btree_current_write(b)->journal - fifo_front_p) &
+		     mask) != 0) {
 			mutex_unlock(&b->write_lock);
 			continue;
 		}
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index 2749daf09724..0c3c5419c52b 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -1917,23 +1917,6 @@ static int run_cache_set(struct cache_set *c)
 		if (bch_btree_check(c))
 			goto err;
 
-		/*
-		 * bch_btree_check() may occupy too much system memory which
-		 * has negative effects to user space application (e.g. data
-		 * base) performance. Shrink the mca cache memory proactively
-		 * here to avoid competing memory with user space workloads..
-		 */
-		if (!c->shrinker_disabled) {
-			struct shrink_control sc;
-
-			sc.gfp_mask = GFP_KERNEL;
-			sc.nr_to_scan = c->btree_cache_used * c->btree_pages;
-			/* first run to clear b->accessed tag */
-			c->shrink.scan_objects(&c->shrink, &sc);
-			/* second run to reap non-accessed nodes */
-			c->shrink.scan_objects(&c->shrink, &sc);
-		}
-
 		bch_journal_mark(c, &journal);
 		bch_initial_gc_finish(c);
 		pr_debug("btree_check() done");