2 files changed, 24 insertions, 7 deletions

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 2c6aedaef718..8ac98ff16d7d 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -1515,6 +1515,7 @@ static int ata_hpa_resize(struct ata_device *dev)
 
                 return rc;
         }
+        dev->n_native_sectors = native_sectors;
 
         /* nothing to do? */
         if (native_sectors <= sectors || !ata_ignore_hpa) {
@@ -4099,6 +4100,7 @@ int ata_dev_revalidate(struct ata_device *dev, unsigned int new_class,
                        unsigned int readid_flags)
 {
         u64 n_sectors = dev->n_sectors;
+        u64 n_native_sectors = dev->n_native_sectors;
         int rc;
 
         if (!ata_dev_enabled(dev))
@@ -4128,16 +4130,30 @@ int ata_dev_revalidate(struct ata_device *dev, unsigned int new_class,
         /* verify n_sectors hasn't changed */
         if (dev->class == ATA_DEV_ATA && n_sectors &&
             dev->n_sectors != n_sectors) {
-                ata_dev_printk(dev, KERN_INFO, "n_sectors mismatch "
+                ata_dev_printk(dev, KERN_WARNING, "n_sectors mismatch "
                                "%llu != %llu\n",
                                (unsigned long long)n_sectors,
                                (unsigned long long)dev->n_sectors);
-
-                /* restore original n_sectors */
-                dev->n_sectors = n_sectors;
-
-                rc = -ENODEV;
-                goto fail;
+                /*
+                 * Something could have caused HPA to be unlocked
+                 * involuntarily.  If n_native_sectors hasn't changed
+                 * and the new size matches it, keep the device.
+                 */
+                if (dev->n_native_sectors == n_native_sectors &&
+                    dev->n_sectors > n_sectors &&
+                    dev->n_sectors == n_native_sectors) {
+                        ata_dev_printk(dev, KERN_WARNING,
+                                       "new n_sectors matches native, probably "
+                                       "late HPA unlock, continuing\n");
+                        /* keep using the old n_sectors */
+                        dev->n_sectors = n_sectors;
+                } else {
+                        /* restore original n_[native]_sectors and fail */
+                        dev->n_native_sectors = n_native_sectors;
+                        dev->n_sectors = n_sectors;
+                        rc = -ENODEV;
+                        goto fail;
+                }
         }
 
         return 0;
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 79b6d7fd4ac2..e5b6e33c6571 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -589,6 +589,7 @@ struct ata_device {
 #endif
         /* n_sector is CLEAR_BEGIN, read comment above CLEAR_BEGIN */
         u64                     n_sectors;      /* size of device, if ATA */
+        u64                     n_native_sectors; /* native size, if ATA */
         unsigned int            class;          /* ATA_DEV_xxx */
         unsigned long           unpark_deadline;