Merge tag 'v5.2-rc6' into for-5.3/block

Merge 5.2-rc6 into for-5.3/block, so we get the same page merge leak
fix. Otherwise we end up having conflicts with future patches between
for-5.3/block and master that touch this area. In particular, it makes
the bio_full() fix hard to backport to stable.

* tag 'v5.2-rc6': (482 commits)
  Linux 5.2-rc6
  Revert "iommu/vt-d: Fix lock inversion between iommu->lock and device_domain_lock"
  Bluetooth: Fix regression with minimum encryption key size alignment
  tcp: refine memory limit test in tcp_fragment()
  x86/vdso: Prevent segfaults due to hoisted vclock reads
  SUNRPC: Fix a credential refcount leak
  Revert "SUNRPC: Declare RPC timers as TIMER_DEFERRABLE"
  net :sunrpc :clnt :Fix xps refcount imbalance on the error path
  NFS4: Only set creation opendata if O_CREAT
  ARM: 8867/1: vdso: pass --be8 to linker if necessary
  KVM: nVMX: reorganize initial steps of vmx_set_nested_state
  KVM: PPC: Book3S HV: Invalidate ERAT when flushing guest TLB entries
  habanalabs: use u64_to_user_ptr() for reading user pointers
  nfsd: replace Jeff by Chuck as nfsd co-maintainer
  inet: clear num_timeout reqsk_alloc()
  PCI/P2PDMA: Ignore root complex whitelist when an IOMMU is present
  net: mvpp2: debugfs: Add pmap to fs dump
  ipv6: Default fib6_type to RTN_UNICAST when not set
  net: hns3: Fix inconsistent indenting
  net/af_iucv: always register net_device notifier
  ...

1 files changed, 22 insertions, 14 deletions

diff --git a/drivers/md/md.c b/drivers/md/md.c
index 692fc365e73c..a114b05e3db4 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -7706,9 +7706,9 @@ static void status_unused(struct seq_file *seq)
 static int status_resync(struct seq_file *seq, struct mddev *mddev)
 {
 	sector_t max_sectors, resync, res;
-	unsigned long dt, db;
-	sector_t rt;
-	int scale;
+	unsigned long dt, db = 0;
+	sector_t rt, curr_mark_cnt, resync_mark_cnt;
+	int scale, recovery_active;
 	unsigned int per_milli;
 
 	if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) ||
@@ -7797,22 +7797,30 @@ static int status_resync(struct seq_file *seq, struct mddev *mddev)
 	 * db: blocks written from mark until now
 	 * rt: remaining time
 	 *
-	 * rt is a sector_t, so could be 32bit or 64bit.
-	 * So we divide before multiply in case it is 32bit and close
-	 * to the limit.
-	 * We scale the divisor (db) by 32 to avoid losing precision
-	 * near the end of resync when the number of remaining sectors
-	 * is close to 'db'.
-	 * We then divide rt by 32 after multiplying by db to compensate.
-	 * The '+1' avoids division by zero if db is very small.
+	 * rt is a sector_t, which is always 64bit now. We are keeping
+	 * the original algorithm, but it is not really necessary.
+	 *
+	 * Original algorithm:
+	 *   So we divide before multiply in case it is 32bit and close
+	 *   to the limit.
+	 *   We scale the divisor (db) by 32 to avoid losing precision
+	 *   near the end of resync when the number of remaining sectors
+	 *   is close to 'db'.
+	 *   We then divide rt by 32 after multiplying by db to compensate.
+	 *   The '+1' avoids division by zero if db is very small.
 	 */
 	dt = ((jiffies - mddev->resync_mark) / HZ);
 	if (!dt) dt++;
-	db = (mddev->curr_mark_cnt - atomic_read(&mddev->recovery_active))
-		- mddev->resync_mark_cnt;
+
+	curr_mark_cnt = mddev->curr_mark_cnt;
+	recovery_active = atomic_read(&mddev->recovery_active);
+	resync_mark_cnt = mddev->resync_mark_cnt;
+
+	if (curr_mark_cnt >= (recovery_active + resync_mark_cnt))
+		db = curr_mark_cnt - (recovery_active + resync_mark_cnt);
 
 	rt = max_sectors - resync;    /* number of remaining sectors */
-	sector_div(rt, db/32+1);
+	rt = div64_u64(rt, db/32+1);
 	rt *= dt;
 	rt >>= 5;