From: Eric W. Biederman The problem: When we are trying to free buffers try_to_free_buffers will look at ramdisk pages with clean buffer heads and remove the dirty bit from the page. Resulting in ramdisk pages with data that get removed from the page cache. Ouch! Buffer heads appear on ramdisk pages when a filesystem calls getblk, which through a series of function calls eventually calls init_page_buffers. So to fix the mismatch between buffer head state and page state this patch modifies init_page_buffers to transfer the dirty bit from the page to the buffer heads like we currently do for the uptodate bit. Signed-off-by: Eric W. Biederman Signed-off-by: Andrew Morton --- fs/buffer.c | 3 +++ 1 file changed, 3 insertions(+) diff -puN fs/buffer.c~preserve-the-dirty-bit-in-init_page_buffers fs/buffer.c --- a/fs/buffer.c~preserve-the-dirty-bit-in-init_page_buffers +++ a/fs/buffer.c @@ -972,6 +972,7 @@ init_page_buffers(struct page *page, str struct buffer_head *head = page_buffers(page); struct buffer_head *bh = head; int uptodate = PageUptodate(page); + int dirty = PageDirty(page); do { if (!buffer_mapped(bh)) { @@ -980,6 +981,8 @@ init_page_buffers(struct page *page, str bh->b_blocknr = block; if (uptodate) set_buffer_uptodate(bh); + if (dirty) + set_buffer_dirty(bh); set_buffer_mapped(bh); } block++; _