scsi: lpfc: Fix panic if driver unloaded when port is offline

[mirror_ubuntu-bionic-kernel.git] / kernel / memremap.c

diff --git a/kernel/memremap.c b/kernel/memremap.c
index 403ab9cdb949a0483bd82c811a3383eed77e5246..9c58979ff743cf0423a692c2a77ed4b496428349 100644 (file)
--- a/kernel/memremap.c
+++ b/kernel/memremap.c
@@ -248,13 +248,16 @@ int device_private_entry_fault(struct vm_area_struct *vma,
 EXPORT_SYMBOL(device_private_entry_fault);
 #endif /* CONFIG_DEVICE_PRIVATE */
 
-static void pgmap_radix_release(struct resource *res)
+static void pgmap_radix_release(struct resource *res, unsigned long end_pgoff)
 {
        unsigned long pgoff, order;
 
        mutex_lock(&pgmap_lock);
-       foreach_order_pgoff(res, order, pgoff)
+       foreach_order_pgoff(res, order, pgoff) {
+               if (pgoff >= end_pgoff)
+                       break;
                radix_tree_delete(&pgmap_radix, PHYS_PFN(res->start) + pgoff);
+       }
        mutex_unlock(&pgmap_lock);
 
        synchronize_rcu();
@@ -301,14 +304,15 @@ static void devm_memremap_pages_release(struct device *dev, void *data)
 
        /* pages are dead and unused, undo the arch mapping */
        align_start = res->start & ~(SECTION_SIZE - 1);
-       align_size = ALIGN(resource_size(res), SECTION_SIZE);
+       align_size = ALIGN(res->start + resource_size(res), SECTION_SIZE)
+               - align_start;
 
        mem_hotplug_begin();
        arch_remove_memory(align_start, align_size);
        mem_hotplug_done();
 
        untrack_pfn(NULL, PHYS_PFN(align_start), align_size);
-       pgmap_radix_release(res);
+       pgmap_radix_release(res, -1);
        dev_WARN_ONCE(dev, pgmap->altmap && pgmap->altmap->alloc,
                        "%s: failed to free all reserved pages\n", __func__);
 }
@@ -351,10 +355,27 @@ void *devm_memremap_pages(struct device *dev, struct resource *res,
        struct dev_pagemap *pgmap;
        struct page_map *page_map;
        int error, nid, is_ram, i = 0;
+       struct dev_pagemap *conflict_pgmap;
 
        align_start = res->start & ~(SECTION_SIZE - 1);
        align_size = ALIGN(res->start + resource_size(res), SECTION_SIZE)
                - align_start;
+       align_end = align_start + align_size - 1;
+
+       conflict_pgmap = get_dev_pagemap(PHYS_PFN(align_start), NULL);
+       if (conflict_pgmap) {
+               dev_WARN(dev, "Conflicting mapping in same section\n");
+               put_dev_pagemap(conflict_pgmap);
+               return ERR_PTR(-ENOMEM);
+       }
+
+       conflict_pgmap = get_dev_pagemap(PHYS_PFN(align_end), NULL);
+       if (conflict_pgmap) {
+               dev_WARN(dev, "Conflicting mapping in same section\n");
+               put_dev_pagemap(conflict_pgmap);
+               return ERR_PTR(-ENOMEM);
+       }
+
        is_ram = region_intersects(align_start, align_size,
                IORESOURCE_SYSTEM_RAM, IORES_DESC_NONE);
 
@@ -392,7 +413,6 @@ void *devm_memremap_pages(struct device *dev, struct resource *res,
 
        mutex_lock(&pgmap_lock);
        error = 0;
-       align_end = align_start + align_size - 1;
 
        foreach_order_pgoff(res, order, pgoff) {
                struct dev_pagemap *dup;
@@ -458,7 +478,7 @@ void *devm_memremap_pages(struct device *dev, struct resource *res,
        untrack_pfn(NULL, PHYS_PFN(align_start), align_size);
  err_pfn_remap:
  err_radix:
-       pgmap_radix_release(res);
+       pgmap_radix_release(res, pgoff);
        devres_free(page_map);
        return ERR_PTR(error);
 }
@@ -517,7 +537,6 @@ void put_zone_device_private_or_public_page(struct page *page)
                __ClearPageActive(page);
                __ClearPageWaiters(page);
 
-               page->mapping = NULL;
                mem_cgroup_uncharge(page);
 
                page->pgmap->page_free(page, page->pgmap->data);