This is a note to let you know that I've just added the patch titled
mm: Fix devm_memremap_pages() collision handling
to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...
The filename of the patch is: mm-fix-devm_memremap_pages-collision-handling.patch and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.
From foo@baz Mon Feb 26 20:55:53 CET 2018
From: Dan Williams dan.j.williams@intel.com Date: Fri, 23 Feb 2018 14:06:10 -0800 Subject: mm: Fix devm_memremap_pages() collision handling To: gregkh@linuxfoundation.org Cc: Message-ID: 151942357089.21775.3486425046348885247.stgit@dwillia2-desk3.amr.corp.intel.com
From: Jan H. Schönherr jschoenh@amazon.de
commit 77dd66a3c67c93ab401ccc15efff25578be281fd upstream.
If devm_memremap_pages() detects a collision while adding entries to the radix-tree, we call pgmap_radix_release(). Unfortunately, the function removes *all* entries for the range -- including the entries that caused the collision in the first place.
Modify pgmap_radix_release() to take an additional argument to indicate where to stop, so that only newly added entries are removed from the tree.
Cc: stable@vger.kernel.org Fixes: 9476df7d80df ("mm: introduce find_dev_pagemap()") Signed-off-by: Jan H. Schönherr jschoenh@amazon.de Signed-off-by: Dan Williams dan.j.williams@intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- kernel/memremap.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-)
--- a/kernel/memremap.c +++ b/kernel/memremap.c @@ -194,7 +194,7 @@ void put_zone_device_page(struct page *p } EXPORT_SYMBOL(put_zone_device_page);
-static void pgmap_radix_release(struct resource *res) +static void pgmap_radix_release(struct resource *res, resource_size_t end_key) { resource_size_t key, align_start, align_size, align_end;
@@ -203,8 +203,11 @@ static void pgmap_radix_release(struct r align_end = align_start + align_size - 1;
mutex_lock(&pgmap_lock); - for (key = res->start; key <= res->end; key += SECTION_SIZE) + for (key = res->start; key <= res->end; key += SECTION_SIZE) { + if (key >= end_key) + break; radix_tree_delete(&pgmap_radix, key >> PA_SECTION_SHIFT); + } mutex_unlock(&pgmap_lock); }
@@ -255,7 +258,7 @@ static void devm_memremap_pages_release( unlock_device_hotplug();
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__); } @@ -289,7 +292,7 @@ struct dev_pagemap *find_dev_pagemap(res void *devm_memremap_pages(struct device *dev, struct resource *res, struct percpu_ref *ref, struct vmem_altmap *altmap) { - resource_size_t key, align_start, align_size, align_end; + resource_size_t key = 0, align_start, align_size, align_end; pgprot_t pgprot = PAGE_KERNEL; struct dev_pagemap *pgmap; struct page_map *page_map; @@ -392,7 +395,7 @@ void *devm_memremap_pages(struct device untrack_pfn(NULL, PHYS_PFN(align_start), align_size); err_pfn_remap: err_radix: - pgmap_radix_release(res); + pgmap_radix_release(res, key); devres_free(page_map); return ERR_PTR(error); }
Patches currently in stable-queue which might be from dan.j.williams@intel.com are
queue-4.9/mm-fix-devm_memremap_pages-collision-handling.patch queue-4.9/ib-core-disable-memory-registration-of-filesystem-dax-vmas.patch queue-4.9/mm-avoid-spurious-bad-pmd-warning-messages.patch queue-4.9/mm-introduce-get_user_pages_longterm.patch queue-4.9/mm-fail-get_vaddr_frames-for-filesystem-dax-mappings.patch queue-4.9/fs-dax.c-fix-inefficiency-in-dax_writeback_mapping_range.patch queue-4.9/device-dax-implement-split-to-catch-invalid-munmap-attempts.patch queue-4.9/v4l2-disable-filesystem-dax-mapping-support.patch queue-4.9/libnvdimm-dax-fix-1gb-aligned-namespaces-vs-physical-misalignment.patch queue-4.9/x86-entry-64-clear-extra-registers-beyond-syscall-arguments-to-reduce-speculation-attack-surface.patch queue-4.9/libnvdimm-fix-integer-overflow-static-analysis-warning.patch