On Wed, Jun 25, 2008 at 05:46:39PM -0700, Mingming wrote: > > On Wed, 2008-06-25 at 09:09 +0000, Holger Kiehl wrote: > > On Tue, 24 Jun 2008, Mingming wrote: > > > > > > > > On Tue, 2008-06-24 at 21:12 +0000, Holger Kiehl wrote: > > >> Yes, with this patch applied on top of latest patch queue I no longer > > >> get truncated files, after running a short test. Tomorrow I will do some > > >> more thorough testing and use the patch you have send to me in a separate > > >> mail. The above patch did not apply but it was easy to apply by hand. > > > > > > > > > Thanks for quick response and test. I have updated the patch queue with > > > above patch merged. Please let me know if you still see apply issue and > > > file size update issue with current patch queue. > > > > > Thanks, it applies without any problems. However I still hit an oops. What > > I find strange is that I got the oops just as the benchmark is done and > > all process where shutting down. The same behaviour I reported here: > > http://www.ussg.iu.edu/hypermail/linux/kernel/0806.2/2113.html > > Only this time I got just one oops. This is on x86_64 system (4 Opteron CPU's > > and SW Raid 1+0). I have not seen this on my home system x86 (1 Dual Core > > and HW Raid). Anyway, here the dmesg output: > > > > kjournald2 starting. Commit interval 15 seconds > > EXT4 FS on md7, internal journal > > EXT4-fs: mounted filesystem with ordered data mode. > > EXT4-fs: file extents enabled > > EXT4-fs: mballoc enabled > > JBD: barrier-based sync failed on md7 - disabling barriers > > ------------[ cut here ]------------ > > kernel BUG at fs/ext4/inode.c:1667! > > Did not get a chance to look more closely today, but it's point to this > code in ext4_da_writepage() > > page_bufs = page_buffers(page); > > and appearently it's BUG_ON at > BUG_ON(!PagePrivate(page)); in page_buffers(). > > Ok so we are doing the journal_commit and meanwhile shrink_page_list dropped the buffer. I guess what is happening is journal_submit_inode_data_buffers generic_writepages write_cache_pages pagevec_lookup_tag(..PAGECACHE_TAG_DIRTY,..) foreach(page) shrink_page_list lock_page ext4_releasepage try_to_free_buffers drop_buffers cancel_dirty_page unlock_page lock_page() BUG_ON(!PagePrivate(page)); How about the below ? I am not sure journalled mode writepage would need a simillar change. We don't need to redirty the page because that would mean the next journal_commit will hit the BUG_ON. If we need to do a BUG_ON diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index fd67b34..94e5ab0 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -1662,8 +1662,17 @@ static int ext4_da_writepage(struct page *page, * writing the page in case we would have to do so. * We reach here also via journal_submit_inode_data_buffers */ + if (!page_has_buffers(page)) { + /* + * This can happen when we are called via + * journal_submit_inode_data_buffers and + * shrink_page_list parallely did drop_buffers + * after write_cache_pages did a pagevec_lookup_tag + */ + unlock_page(page); + return 0; + } size = i_size_read(inode); - page_bufs = page_buffers(page); if (page->index == size >> PAGE_CACHE_SHIFT) len = size & ~PAGE_CACHE_MASK; @@ -2046,7 +2055,16 @@ static int ext4_normal_writepage(struct page *page, loff_t len; J_ASSERT(PageLocked(page)); - J_ASSERT(page_has_buffers(page)); + if (!page_has_buffers(page)) { + /* + * This can happen when we are called via + * journal_submit_inode_data_buffers and + * shrink_page_list parallely did drop_buffers + * after write_cache_pages did a pagevec_lookup_tag + */ + unlock_page(page); + return 0; + } if (page->index == size >> PAGE_CACHE_SHIFT) len = size & ~PAGE_CACHE_MASK; else -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
