From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965171AbXBFDGX (ORCPT ); Mon, 5 Feb 2007 22:06:23 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S965251AbXBFDGX (ORCPT ); Mon, 5 Feb 2007 22:06:23 -0500 Received: from smtp.osdl.org ([65.172.181.24]:46482 "EHLO smtp.osdl.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965171AbXBFDGW (ORCPT ); Mon, 5 Feb 2007 22:06:22 -0500 Date: Mon, 5 Feb 2007 19:06:19 -0800 From: Andrew Morton To: Robert Hancock Cc: linux-kernel Subject: Re: 2.6.20-rc6-mm3 and NTFS: BUG: at arch/i386/mm/highmem.c:52 kmap_atomic() Message-Id: <20070205190619.9f8a091a.akpm@linux-foundation.org> In-Reply-To: <45C7EE27.1020802@shaw.ca> References: <45C7EE27.1020802@shaw.ca> X-Mailer: Sylpheed version 2.2.7 (GTK+ 2.8.17; x86_64-unknown-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 05 Feb 2007 20:55:35 -0600 Robert Hancock wrote: > Seeing these BUGs on 2.6.20-rc6-mm3 when mounting an NTFS partition. I > saw some reports of something like this on -mm1, was this supposed to be > patched already? > > BUG: at arch/i386/mm/highmem.c:52 kmap_atomic() > [] kmap_atomic+0xb4/0x1cd > [] ntfs_end_buffer_async_read+0x276/0x2db [ntfs] > [] end_bio_bh_io_sync+0x0/0x39 > [] end_bio_bh_io_sync+0x2e/0x39 > [] bio_endio+0x5b/0x63 > [] _spin_lock_irqsave+0x9/0xd > [] lock_timer_base+0x15/0x2f > [] __end_that_request_first+0x176/0x421 > [] scsi_delete_timer+0xf/0x50 [scsi_mod] > [] scsi_request_fn+0x2d4/0x324 [scsi_mod] > [] ata_scsi_qc_complete+0x344/0x354 [libata] > [] __blk_run_queue+0x17/0x35 > [] scsi_end_request+0x1a/0xa8 [scsi_mod] > [] scsi_io_completion+0x15a/0x32b [scsi_mod] > [] pit_next_event+0x2b/0x2f > [] sd_rw_intr+0x21b/0x245 [sd_mod] > [] scsi_finish_command+0x84/0x8b [scsi_mod] > [] blk_done_softirq+0x49/0x54 > [] __do_softirq+0x5d/0xba > [] do_softirq+0x32/0x36 > [] irq_exit+0x38/0x6b > [] do_IRQ+0x87/0x9c > [] common_interrupt+0x23/0x28 > [] __dequeue_signal+0x97/0x14e > [] acpi_processor_idle+0x209/0x3ca > [] acpi_processor_idle+0x0/0x3ca > [] cpu_idle+0xaa/0xd0 > [] start_kernel+0x435/0x43d > [] unknown_bootoption+0x0/0x202 Yes, that was a real bug. It got fixed in 2.6.20. Below is the fix, which I have just uploaded to the hot-fixes directory, thanks. --- a/fs/ntfs/aops.c~ntfs-kmap_atomic-atomicity-fix +++ a/fs/ntfs/aops.c @@ -92,10 +92,12 @@ static void ntfs_end_buffer_async_read(s ofs = 0; if (file_ofs < init_size) ofs = init_size - file_ofs; + local_irq_save(flags); kaddr = kmap_atomic(page, KM_BIO_SRC_IRQ); memset(kaddr + bh_offset(bh) + ofs, 0, bh->b_size - ofs); kunmap_atomic(kaddr, KM_BIO_SRC_IRQ); + local_irq_restore(flags); flush_dcache_page(page); } } else { @@ -143,11 +145,13 @@ static void ntfs_end_buffer_async_read(s recs = PAGE_CACHE_SIZE / rec_size; /* Should have been verified before we got here... */ BUG_ON(!recs); + local_irq_save(flags); kaddr = kmap_atomic(page, KM_BIO_SRC_IRQ); for (i = 0; i < recs; i++) post_read_mst_fixup((NTFS_RECORD*)(kaddr + i * rec_size), rec_size); kunmap_atomic(kaddr, KM_BIO_SRC_IRQ); + local_irq_restore(flags); flush_dcache_page(page); if (likely(page_uptodate && !PageError(page))) SetPageUptodate(page); _