Subject: + mm-__set_page_dirty-uses-spin_lock_irqsave-instead-of-spin_lock_irq.patch added to -mm tree To: kosaki.motohiro@xxxxxxxxxxxxxx,stable@xxxxxxxxxxxxxxx From: akpm@xxxxxxxxxxxxxxxxxxxx Date: Wed, 05 Feb 2014 13:37:52 -0800 The patch titled Subject: mm: __set_page_dirty uses spin_lock_irqsave instead of spin_lock_irq has been added to the -mm tree. Its filename is mm-__set_page_dirty-uses-spin_lock_irqsave-instead-of-spin_lock_irq.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/mm-__set_page_dirty-uses-spin_lock_irqsave-instead-of-spin_lock_irq.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/mm-__set_page_dirty-uses-spin_lock_irqsave-instead-of-spin_lock_irq.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx> Subject: mm: __set_page_dirty uses spin_lock_irqsave instead of spin_lock_irq To use spin_{un}lock_irq is dangerous if caller disabled interrupt. During aio buffer migration, we have a possibility to see the following call stack. aio_migratepage [disable interrupt] migrate_page_copy clear_page_dirty_for_io set_page_dirty __set_page_dirty_buffers __set_page_dirty spin_lock_irq This mean, current aio migration is a deadlockable. spin_lock_irqsave is a safer alternative and we should use it. Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx> Reported-by: David Rientjes rientjes@xxxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- fs/buffer.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff -puN fs/buffer.c~mm-__set_page_dirty-uses-spin_lock_irqsave-instead-of-spin_lock_irq fs/buffer.c --- a/fs/buffer.c~mm-__set_page_dirty-uses-spin_lock_irqsave-instead-of-spin_lock_irq +++ a/fs/buffer.c @@ -654,14 +654,16 @@ EXPORT_SYMBOL(mark_buffer_dirty_inode); static void __set_page_dirty(struct page *page, struct address_space *mapping, int warn) { - spin_lock_irq(&mapping->tree_lock); + unsigned long flags; + + spin_lock_irqsave(&mapping->tree_lock, flags); if (page->mapping) { /* Race with truncate? */ WARN_ON_ONCE(warn && !PageUptodate(page)); account_page_dirtied(page, mapping); radix_tree_tag_set(&mapping->page_tree, page_index(page), PAGECACHE_TAG_DIRTY); } - spin_unlock_irq(&mapping->tree_lock); + spin_unlock_irqrestore(&mapping->tree_lock, flags); __mark_inode_dirty(mapping->host, I_DIRTY_PAGES); } _ Patches currently in -mm which might be from kosaki.motohiro@xxxxxxxxxxxxxx are mm-__set_page_dirty_nobuffers-uses-spin_lock_irqseve-instead-of-spin_lock_irq.patch mm-__set_page_dirty-uses-spin_lock_irqsave-instead-of-spin_lock_irq.patch mm-vmstat-fix-up-zone-state-accounting.patch fs-cachefiles-use-add_to_page_cache_lru.patch lib-radix-tree-radix_tree_delete_item.patch mm-shmem-save-one-radix-tree-lookup-when-truncating-swapped-pages.patch mm-filemap-move-radix-tree-hole-searching-here.patch mm-fs-prepare-for-non-page-entries-in-page-cache-radix-trees.patch mm-fs-store-shadow-entries-in-page-cache.patch mm-thrash-detection-based-file-cache-sizing.patch lib-radix_tree-tree-node-interface.patch mm-keep-page-cache-radix-tree-nodes-in-check.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html