On Mon, Nov 15, 2010 at 11:54 AM, Markus Trippelsdorf <markus@xxxxxxxxxxxxxxx> wrote: > On 2010.11.15 at 13:38 +0100, Markus Trippelsdorf wrote: >> On 2010.11.12 at 13:20 +0100, Markus Trippelsdorf wrote: >> > >> > Yes. Fortunately the BUG is gone since I pulled the upcoming drm fixes >> >> No. I happend again today (with those fixes already applied): >> >> BUG: Bad page state in process knode Âpfn:7f0a8 >> page:ffffea0001bca4c0 count:0 mapcount:0 mapping: Â Â Â Â Â(null) index:0x0 >> page flags: 0x4000000000000008(uptodate) >> Pid: 18310, comm: knode Not tainted 2.6.37-rc1-00549-gae712bf-dirty #16 >> Call Trace: >> Â[<ffffffff810a9022>] ? bad_page+0x92/0xe0 >> Â[<ffffffff810aa240>] ? get_page_from_freelist+0x4b0/0x570 >> Â[<ffffffff8102e50e>] ? apic_timer_interrupt+0xe/0x20 >> Â[<ffffffff810aa413>] ? __alloc_pages_nodemask+0x113/0x6b0 >> Â[<ffffffff810a2dd4>] ? file_read_actor+0xc4/0x190 >> Â[<ffffffff810a4a70>] ? generic_file_aio_read+0x560/0x6b0 >> Â[<ffffffff810bdf8d>] ? handle_mm_fault+0x6bd/0x970 >> Â[<ffffffff8104b1d0>] ? do_page_fault+0x120/0x410 >> Â[<ffffffff810c3d85>] ? do_brk+0x275/0x360 >> Â[<ffffffff81452d8f>] ? page_fault+0x1f/0x30 >> Disabling lock debugging due to kernel taint > > And another one. But this time it seems to point to ext4: > > BUG: Bad page state in process rm Âpfn:52e54 > page:ffffea0001222260 count:0 mapcount:0 mapping: Â Â Â Â Â(null) index:0x0 > page flags: 0x4000000000000008(uptodate) > Pid: 2084, comm: rm Not tainted 2.6.37-rc1-00549-gae712bf-dirty #23 > Call Trace: > Â[<ffffffff810a9022>] ? bad_page+0x92/0xe0 > Â[<ffffffff810aa240>] ? get_page_from_freelist+0x4b0/0x570 > Â[<ffffffff81142ae6>] ? ext4_ext_put_in_cache+0x46/0x90 > Â[<ffffffff810aa413>] ? __alloc_pages_nodemask+0x113/0x6b0 > Â[<ffffffff8118f0c7>] ? number.clone.2+0x2b7/0x2f0 > Â[<ffffffff810a38d5>] ? find_get_page+0x75/0xb0 > Â[<ffffffff810a4011>] ? find_or_create_page+0x51/0xb0 > Â[<ffffffff810ff4d7>] ? __getblk+0xd7/0x260 > Â[<ffffffff8113158f>] ? ext4_getblk+0x8f/0x1e0 > Â[<ffffffff811316ed>] ? ext4_bread+0xd/0x70 > Â[<ffffffff811369f4>] ? htree_dirblock_to_tree+0x34/0x190 > Â[<ffffffff8113870f>] ? ext4_htree_fill_tree+0x9f/0x250 > Â[<ffffffff810e109d>] ? do_filp_open+0x12d/0x5e0 > Â[<ffffffff811289ed>] ? ext4_readdir+0x14d/0x5a0 > Â[<ffffffff810e4e80>] ? filldir+0x0/0xd0 > Â[<ffffffff810e50a8>] ? vfs_readdir+0xa8/0xd0 > Â[<ffffffff810e4e80>] ? filldir+0x0/0xd0 > Â[<ffffffff810e51b1>] ? sys_getdents+0x81/0xf0 > Â[<ffffffff8102dc2b>] ? system_call_fastpath+0x16/0x1b > Disabling lock debugging due to kernel taint > > I don't know. Could a possible bug in linux/fs/ext4/page-io.c be > responsible for something like this? I do think you're right: every one of your "Bad page state" reports has been complaining only about the PageUptodate bit being set, and that SetPageUpdate() in ext4_end_bio() does look suspicious, coming after the put_page(). The more suspicious given that other races have been noticed in precisely that area, and fixed with put_io_page() in the current git tree. Perhaps that fixes your problem, but my guess would be not: I suspect the "if (!partial_write) SetPageUpdate(page);" should be done before the block (or put_io_page) which does the put_page(). Hugh -- 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
