[PATCH v8 06/12] zloop: fix zone reporting consistency

[Damien Le Moal <dlemoal@kernel.org>]

In zloop_report_zones(), filling the write pointer and condition of a zone
descriptor separately outside of the zone wp_lock can lead to an
inconsistent zone report with a write pointer potentially not being
consistent with the condition being reported. Avoid such inconsistency by
filling both fields while holding the zone wp_lock.

Fixes: fcc6eaa3a03a ("zloop: introduce the ordered_zone_append configuration parameter")
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
---
 drivers/block/zloop.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/block/zloop.c b/drivers/block/zloop.c
index 96666742523b..844a9f5db6a4 100644
--- a/drivers/block/zloop.c
+++ b/drivers/block/zloop.c
@@ -992,8 +992,8 @@ static int zloop_report_zones(struct gendisk *disk, sector_t sector,
 		blkz.len = zlo->zone_size;
 		spin_lock(&zone->wp_lock);
 		blkz.wp = zone->wp;
-		spin_unlock(&zone->wp_lock);
 		blkz.cond = zone->cond;
+		spin_unlock(&zone->wp_lock);
 		if (test_bit(ZLOOP_ZONE_CONV, &zone->flags)) {
 			blkz.type = BLK_ZONE_TYPE_CONVENTIONAL;
 			blkz.capacity = zlo->zone_size;
-- 
2.56.0