From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <50558F98.1070208@xenomai.org> Date: Sun, 16 Sep 2012 10:36:40 +0200 From: Philippe Gerum MIME-Version: 1.0 References: <504F5F1B.4020806@siemens.com> <50550091.50002@xenomai.org> <50557DC5.7070507@web.de> In-Reply-To: <50557DC5.7070507@web.de> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Subject: Re: [Xenomai] ipipe/x86: kernel BUG due to missing IRQ_MOVE_CLEANUP_VECTOR entry in ipipe-core3.2 List-Id: Discussions about the Xenomai project List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Jan Kiszka Cc: xenomai@xenomai.org On 09/16/2012 09:20 AM, Jan Kiszka wrote: > On 2012-09-16 00:26, Gilles Chanteperdrix wrote: >> On 09/11/2012 05:56 PM, Gernot Hillier wrote: >> >>> Hi there! >>> >>> While testing ipipe-core3.2 on an SMP x86 machine, I found a reproducible >>> kernel BUG after some seconds after starting irqbalance: >>> >>> ------------[ cut here ]------------ >>> kernel BUG at arch/x86/kernel/ipipe.c:592! >>> invalid opcode: 0000 [#1] SMP >>> CPU 0 >>> Modules linked in: des_generic md4 i7core_edac psmouse nls_cp437 edac_core cifs serio_raw joydev raid10 raid456 async_pq async_xor xor async_memcpy async_raid6_recov usbhid hid mpt2sas scsi_transport_sas raid_class igb raid6_pq async_tx raid1 raid0 multipath linear >>> >>> Pid: 0, comm: swapper/0 Not tainted 3.2.21-9-xenomai #3 Siemens AG Healthcare Sector MARS 2.1/X8DTH >>> RIP: 0010:[] [] __ipipe_handle_irq+0x1bc/0x1d0 >>> RSP: 0018:ffffffff8177bbe0 EFLAGS: 00010086 >>> RAX: 000000000000d880 RBX: 00000000ffffffff RCX: 0000000000000092 >>> RDX: ffffffffffffffdf RSI: ffffffff8177bc18 RDI: ffffffff8177bbf8 >>> RBP: ffffffff8177bc00 R08: 0000000000000001 R09: 0000000000000000 >>> R10: ffff880624ebaef8 R11: 000000000029fbc4 R12: 000000000000d880 >>> R13: ffffffff8177bbf8 R14: ffff880624e00000 R15: ffff880624e0d880 >>> FS: 0000000000000000(0000) GS:ffff880624e00000(0000) knlGS:0000000000000000 >>> CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b >>> CR2: 00007f452a2efb80 CR3: 0000000c114d3000 CR4: 00000000000006f0 >>> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 >>> DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 >>> Process swapper/0 (pid: 0, threadinfo ffffffff81778000, task ffffffff81787020) >>> Stack: >>> 0000000000000000 ffffffff8177bfd8 0000000000000063 ffff880624e1f9a8 >>> ffffffff8177bca8 ffffffff815a44dd ffffffff8177bc18 ffffffff8177bca8 >>> 00000000815a373b 000000000029fbc4 ffff880624eba570 0000000000000000 >>> Call Trace: >>> [] irq_move_cleanup_interrupt+0x5d/0x90 >>> [] ? call_softirq+0x19/0x30 >>> [] do_softirq+0xc5/0x100 >>> [] irq_exit+0xd5/0xf0 >>> [] do_IRQ+0x6f/0x100 >>> [] ? __entry_text_end+0x5/0x5 >>> [] __ipipe_do_IRQ+0x83/0xa0 >>> [] ? __ipipe_do_IRQ+0x89/0xa0 >>> [] __ipipe_dispatch_irq_fast+0x16a/0x170 >>> [] __ipipe_dispatch_irq+0xe9/0x210 >>> [] __ipipe_handle_irq+0x71/0x1d0 >>> [] common_interrupt+0x60/0x81 >>> [] ? __ipipe_halt_root+0x34/0x50 >>> [] ? __ipipe_halt_root+0x27/0x50 >>> [] default_idle+0x66/0x1a0 >>> [] cpu_idle+0xaf/0x100 >>> [] rest_init+0x72/0x80 >>> [] start_kernel+0x3b4/0x3bf >>> [] x86_64_start_reservations+0x131/0x135 >>> [] x86_64_start_kernel+0x131/0x138 >>> Code: ff ff 0f 1f 44 00 00 48 83 a0 98 06 00 00 fe 4c 89 ee bf 20 00 00 00 e8 63 83 09 00 e9 f6 fe ff ff be 01 00 00 00 e9 ab fe ff ff <0f> 0b 66 90 eb fc 66 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 55 >>> RIP [] __ipipe_handle_irq+0x1bc/0x1d0 >>> RSP >>> >>> This seems to be caused by a missing entry for IRQ_MOVE_CLEANUP_VECTOR >>> in the per_cpu array vector_irq[]. >>> >>> I found that ipipe_init_vector_irq() (which used to add the needed >>> entry) was factored out from arch/x86/kernel/ipipe.c. This likely >>> happened when porting from 2.6.38 to 3.1 - at least I can still see the >>> code in ipipe-2.6.38-x86 and missed it in ipipe-core3.1 (and didn't find >>> any x86-branch in-between). >> >> >> If I understand correctly, ipipe_init_vector_irq is no longer needed >> because the I-pipe core uses ipipe_apic_vector_irq for vectors above >> FIRST_SYSTEM_VECTOR. All system vectors are above this limit... except >> IRQ_MOVE_CLEANUP_VECTOR. So, your patch is correct. Another one which >> should work is to handle the special case IRQ_MOVE_CLEANUP_IRQ in >> __ipipe_handle_irq as well. > > The idea of ipipe_init_vector_irq, i.e. filling of vector_irq beyond > what Linux needs, was to avoid all these special cases. Unless there was > a need to leave vector_irq alone in 3.x, we should simply restore this > cleaner approach from 2.6.3x. That's what Gernot's question is aiming at. > Ack. The change was wrongly assuming that special vectors would always belong to the system range. Please revert this. -- Philippe.