Hi Kirill, I add dump_page(page) in function ubifs_set_page_dirty. And get this log when ubifs assert fail. Is it helpful for this problem? page:81411740 count:3 mapcount:1 mapping:a33db634 index:0x0 page flags: 0x219(locked|uptodate|dirty|arch_1) UBIFS assert failed in ubifs_set_page_dirty at 1424 (pid 545) CPU: 1 PID: 545 Comm: kswapd0 Tainted: P O 3.10.0_s40 #18 [<8001d8a0>] (unwind_backtrace+0x0/0x108) from [<80019f44>] (show_stack+0x20/0x24) [<80019f44>] (show_stack+0x20/0x24) from [<80acf9f8>] (dump_stack+0x24/0x2c) [<80acf9f8>] (dump_stack+0x24/0x2c) from [<80298870>] (ubifs_set_page_dirty+0x60/0x6c) [<80298870>] (ubifs_set_page_dirty+0x60/0x6c) from [<800cea60>] (set_page_dirty+0x50/0x78) [<800cea60>] (set_page_dirty+0x50/0x78) from [<800f4be4>] (try_to_unmap_one+0x1f8/0x3d0) [<800f4be4>] (try_to_unmap_one+0x1f8/0x3d0) from [<800f4f44>] (try_to_unmap_file+0x9c/0x740) [<800f4f44>] (try_to_unmap_file+0x9c/0x740) from [<800f5678>] (try_to_unmap+0x40/0x78) [<800f5678>] (try_to_unmap+0x40/0x78) from [<800d6a04>] (shrink_page_list+0x23c/0x884) [<800d6a04>] (shrink_page_list+0x23c/0x884) from [<800d76c8>] (shrink_inactive_list+0x21c/0x3c8) [<800d76c8>] (shrink_inactive_list+0x21c/0x3c8) from [<800d7c20>] (shrink_lruvec+0x3ac/0x524) [<800d7c20>] (shrink_lruvec+0x3ac/0x524) from [<800d8970>] (kswapd+0x854/0xdc0) [<800d8970>] (kswapd+0x854/0xdc0) from [<80051e28>] (kthread+0xc8/0xcc) [<80051e28>] (kthread+0xc8/0xcc) from [<80015198>] (ret_from_fork+0x14/0x20) > -----Original Message----- > From: Kirill A. Shutemov [mailto:kirill@xxxxxxxxxxxxx] > Sent: Thursday, November 20, 2014 8:30 PM > To: Hujianyang > Cc: dedekind1@xxxxxxxxx; Caizhiyong; linux-fsdevel@xxxxxxxxxxxxxxx; > linux-mm@xxxxxxxxx; Wanli (welly); linux-mtd@xxxxxxxxxxxxxxxxxxx; > adrian.hunter@xxxxxxxxx; Jijiagang > Subject: Re: UBIFS assert failed in ubifs_set_page_dirty at 1421 > > On Fri, Nov 07, 2014 at 10:22:38AM +0800, hujianyang wrote: > > Hi, > > > > I think we found the cause of this problem. We enable CONFIG_CMA in > > our config file. This feature seems to allocate a contiguous memory for caller. > > If some pages in this contiguous area are used by other modules, like > > UBIFS, CMA will migrate these pages to other place. This operation > > should be transparent to the user of old pages. But it is *not true* for UBIFS. > > > > > > > > 1. UBIFS wants to make sure that no one marks UBIFS-backed pages > > > (and actually inodes too) as dirty directly. UBIFS wants everyone to > > > ask UBIFS to mark a page as dirty. > > > > > > 2. This is because for every dirty page, UBIFS needs to reserve > > > certain amount of space on the flash media, because all writes are > > > out-of-place, even when you are changing an existing file. > > > > > > 3. There are exactly 2 places where UBIFS-backed pages may be marked > > > as > > > dirty: > > > > > > a) ubifs_write_end() [->wirte_end] - the file write path > > > b) ubifs_page_mkwrite() [->page_mkwirte] - the file mmap() path > > > > line 1160, func try_to_unmap_one() in mm/rmap.c > > > > "" > > /* Move the dirty bit to the physical page now the pte is gone. */ > > if (pte_dirty(pteval)) > > set_page_dirty(page); > > "" > > > > Here, If the pte of a page is dirty, a directly set_page_dirty() is > > performed and hurt the internal logic of UBIFS. > > If the pte is dirty it must be writable too. And to make pte writable > ->page_mkwrite() must be called. So it should work fine.. > > Could you check if the pteval is pte_write() by the time? > And could you provide what says dump_page(page) and dump_vma(vma) while > you are there? > > -- > Kirill A. Shutemov -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href