From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Rientjes Subject: Re: [Bug #13116] Can't boot with nosmp Date: Tue, 28 Apr 2009 15:14:23 -0700 (PDT) Message-ID: References: <47KgT3nlbjD.A.lnB.jc48JB@chimera> <49F4DF40.50302@intel.com> Mime-Version: 1.0 Return-path: DKIM-Signature: v=1; a=rsa-sha1; c=relaxed/relaxed; d=google.com; s=beta; t=1240956868; bh=7o4Wt0axkYeT0H1WcM949L+0Ay4=; h=DomainKey-Signature:Date:From:X-X-Sender:To:cc:Subject: In-Reply-To:Message-ID:References:User-Agent:MIME-Version: Content-Type:X-System-Of-Record; b=ay+s95OAsZdNBHyIp9g8tUANMOijofy p889kfZLIAFIPuxWW9EXSSB0xgqEkZfFTsDGo1MkV0U7/hIZJnLtA4g== In-Reply-To: <49F4DF40.50302-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org> Sender: kernel-testers-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: Content-Type: TEXT/PLAIN; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Dan Williams Cc: "Rafael J. Wysocki" , Linux Kernel Mailing List , Kernel Testers List , Stephen Hemminger On Sun, 26 Apr 2009, Dan Williams wrote: > Rafael J. Wysocki wrote: > > This message has been generated automatically as a part of a report > > of recent regressions. > > > > The following bug entry is on the current list of known regressions > > from 2.6.29. Please verify if it still should be listed and let me know > > (either way). > > This is still unresolved. > > Stephen, please send your config. > Given the stack for the initial report, why would a config other than enabling CONFIG_DMA_ENGINE help if there's no ifdefs involved? This is happening in the for_each_possible_cpu() loop within dma_channel_rebalance(), which makes sense since the machine boots fine normally but not with `nosmp'. channel_table[] is not being initialized per-cpu for non-online cpus? BUG: unable to handle kernel NULL pointer dereference at (null) IP: [] dma_channel_rebalance+0x46/0x1d1 PGD 1d8db067 PUD 179bc067 PMD 0 Oops: 0002 [#1] SMP last sysfs file: /sys/kernel/uevent_seqnum CPU 0 Modules linked in: async_tx(+) xor raid1 raid0 multipath linear md_mod virtio_blk sg sr_mod cdrom \ pata_acpi virtio_pci virtio_ring virtio floppy uhci_hcd usbcore ata_piix ata_generic thermal processor \ fan thermal_sys Pid: 1789, comm: modprobe Not tainted 2.6.29-1-amd64-vyatta #1 RIP: 0010:[] [] dma_channel_rebalance+0x46/0x1d1 RSP: 0018:ffff880017a6de78 EFLAGS: 00010283 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000001 RDX: 0000000000000001 RSI: 0000000000000001 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000020 R09: ffffffff8063ab00 R10: ffffffffa0106d80 R11: ffff880001010300 R12: 000000000000000c R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 00007fe9c51536e0(0000) GS:ffffffff806ac080(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 0000000000000000 CR3: 000000001d903000 CR4: 00000000000006e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process modprobe (pid: 1789, threadinfo ffff880017a6c000, task ffff88001fb14380) Stack: 0000000000000000 ffffffff805fc4e8 0000000000001ee9 ffffffff805fc4e8 0000000000000000 0000000000000000 0000000000000000 ffffffff803d730a 00000000fffffffe ffffffffa0106d80 0000000000001ee9 ffffffffa0109000 Call Trace: [] dmaengine_get+0xca/0xdd [] async_tx_init+0x0/0x1b [async_tx] [] async_tx_init+0x9/0x1b [async_tx] [] _stext+0x51/0x120 [] __up_read+0x13/0x8d [] __blocking_notifier_call_chain+0x51/0x5f [] sys_init_module+0xa0/0x1ba [] system_call_fastpath+0x16/0x1b