On 04/06/15 at 07:26am, Yasuaki Ishimatsu wrote: > Hi, > > On Fri, 3 Apr 2015 15:15:13 +0800 > Dave Young <dyo...@redhat.com> wrote: > > > Hi, > > > > On 04/02/15 at 12:36pm, Yasuaki Ishimatsu wrote: > > > > > > On Wed, 1 Apr 2015 12:53:46 +0800 > > > Dave Young <dyo...@redhat.com> wrote: > > > > > > > I got below kernel panic during kdump test on Thinkpad T420 laptop: > > > > > > > > [ 0.000000] No NUMA configuration found > > > > > > > > [ 0.000000] Faking a node at [mem > > > > 0x0000000000000000-0x0000000037ba4fff] > > > > [ 0.000000] Kernel panic - not syncing: stack-protector: Kernel > > > > stack is cor > > > > upted in: ffffffff81d21910 > > > > r > > > > [ 0.000000] > > > > > > > > [ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 4.0.0-rc6+ #44 > > > > > > > > [ 0.000000] Hardware name: LENOVO 4236NUC/4236NUC, BIOS 83ET76WW > > > > (1.46 ) 07/ > > > > 5/2013 > > > > 0 > > > > [ 0.000000] 0000000000000000 c70296ddd809e4f6 ffffffff81b67ce8 > > > > ffffffff817c > > > > a26 > > > > 2 > > > > [ 0.000000] 0000000000000000 ffffffff81a61c90 ffffffff81b67d68 > > > > ffffffff817b > > > > 8d2 > > > > c > > > > [ 0.000000] 0000000000000010 ffffffff81b67d78 ffffffff81b67d18 > > > > c70296ddd809 > > > > 4f6 > > > > e > > > > [ 0.000000] Call Trace: > > > > > > > > [ 0.000000] [<ffffffff817c2a26>] dump_stack+0x45/0x57 > > > > > > > > [ 0.000000] [<ffffffff817bc8d2>] panic+0xd0/0x204 > > > > > > > > [ 0.000000] [<ffffffff81d21910>] ? > > > > numa_clear_kernel_node_hotplug+0xe6/0xf2 > > > > [ 0.000000] [<ffffffff8107741b>] __stack_chk_fail+0x1b/0x20 > > > > > > > > [ 0.000000] [<ffffffff81d21910>] > > > > numa_clear_kernel_node_hotplug+0xe6/0xf2 > > > > [ 0.000000] [<ffffffff81d21e5d>] numa_init+0x1a5/0x520 > > > > > > > > [ 0.000000] [<ffffffff81d222b1>] x86_numa_init+0x19/0x3d > > > > > > > > [ 0.000000] [<ffffffff81d22460>] initmem_init+0x9/0xb > > > > > > > > [ 0.000000] [<ffffffff81d0d00c>] setup_arch+0x94f/0xc82 > > > > > > > > [ 0.000000] [<ffffffff81d05120>] ? early_idt_handlers+0x120/0x120 > > > > > > > > [ 0.000000] [<ffffffff817bd0bb>] ? printk+0x55/0x6b > > > > > > > > [ 0.000000] [<ffffffff81d05120>] ? early_idt_handlers+0x120/0x120 > > > > > > > > [ 0.000000] [<ffffffff81d05d9b>] start_kernel+0xe8/0x4d6 > > > > > > > > [ 0.000000] [<ffffffff81d05120>] ? early_idt_handlers+0x120/0x120 > > > > > > > > [ 0.000000] [<ffffffff81d05120>] ? early_idt_handlers+0x120/0x120 > > > > > > > > [ 0.000000] [<ffffffff81d055ee>] > > > > x86_64_start_reservations+0x2a/0x2c > > > > [ 0.000000] [<ffffffff81d05751>] x86_64_start_kernel+0x161/0x184 > > > > > > > > [ 0.000000] ---[ end Kernel panic - not syncing: stack-protector: > > > > Kernel sta > > > > k is corrupted in: ffffffff81d21910 > > > > c > > > > [ 0.000000] > > > > > > > > PANIC: early exception 0d rip 10:ffffffff8105d2a6 error 7eb cr2 > > > > ffff8800371dd00 > > > > [ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 4.0.0-rc6+ #44 > > > > 0 > > > > [ 0.000000] Hardware name: LENOVO 4236NUC/4236NUC, BIOS 83ET76WW > > > > (1.46 ) 07/ > > > > 5/2013 > > > > 0 > > > > [ 0.000000] 0000000000000000 c70296ddd809e4f6 ffffffff81b67c60 > > > > ffffffff817c > > > > a26 > > > > 2 > > > > [ 0.000000] 0000000000000096 ffffffff81a61c90 ffffffff81b67d68 > > > > fffffff00000 > > > > 084 0000000000000a0d 0000000000000a00 > > > > 0 > > > > [ 0.000000] Call Trace: > > > > > > > > [ 0.000000] [<ffffffff817c2a26>] dump_stack+0x45/0x57 > > > > > > > > [ 0.000000] [<ffffffff81d051b0>] early_idt_handler+0x90/0xb7 > > > > > > > > [ 0.000000] [<ffffffff8105d2a6>] ? native_irq_enable+0x6/0x10 > > > > > > > > [ 0.000000] [<ffffffff817bc9c5>] ? panic+0x1c3/0x204 > > > > > > > > [ 0.000000] [<ffffffff81d21910>] ? > > > > numa_clear_kernel_node_hotplug+0xe6/0xf2 > > > > [ 0.000000] [<ffffffff8107741b>] __stack_chk_fail+0x1b/0x20 > > > > > > > > [ 0.000000] [<ffffffff81d21910>] > > > > numa_clear_kernel_node_hotplug+0xe6/0xf2 > > > > [ 0.000000] [<ffffffff81d21e5d>] numa_init+0x1a5/0x520 > > > > > > > > [ 0.000000] [<ffffffff81d222b1>] x86_numa_init+0x19/0x3d > > > > > > > > [ 0.000000] [<ffffffff81d22460>] initmem_init+0x9/0xb > > > > > > > > [ 0.000000] [<ffffffff81d0d00c>] setup_arch+0x94f/0xc82 > > > > > > > > [ 0.000000] [<ffffffff81d05120>] ? early_idt_handlers+0x120/0x120 > > > > > > > > [ 0.000000] [<ffffffff817bd0bb>] ? printk+0x55/0x6b > > > > > > > > [ 0.000000] [<ffffffff81d05120>] ? early_idt_handlers+0x120/0x120 > > > > > > > > [ 0.000000] [<ffffffff81d05d9b>] start_kernel+0xe8/0x4d6 > > > > > > > > [ 0.000000] [<ffffffff81d05120>] ? early_idt_handlers+0x120/0x120 > > > > > > > > [ 0.000000] [<ffffffff81d05120>] ? early_idt_handlers+0x120/0x120 > > > > > > > > [ 0.000000] [<ffffffff81d055ee>] > > > > x86_64_start_reservations+0x2a/0x2c > > > > [ 0.000000] [<ffffffff81d05751>] x86_64_start_kernel+0x161/0x184 > > > > > > > > [ 0.000000] RIP 0x46 > > > > > > > > > > > > This is caused by writing over end of numa mask bitmap. > > > > > > > > numa_clear_kernel_node try to set node id in a mask bitmap, it > > > > iterating all > > > > reserved region and assume every regions have valid nid. It is not true > > > > because > > > > There's an exception for graphic memory quirks. see function > > > > trim_snb_memory > > > > in arch/x86/kernel/setup.c > > > > > > > > It is easily to reproduce the bug in kdump kernel because kdump kernel > > > > use > > > > prereserved memory instead of whole memory, but kexec pass other > > > > reserved memory > > > > ranges to 2nd kernel as well. like below in my test: > > > > kdump kernel ram 0x2d000000 - 0x37bfffff > > > > One of the reserved regions: 0x40000000 - 0x40100000 > > > > > > > > The above reserved region includes 0x40004000, a page excluded in > > > > trim_snb_memory. For this memblock reserved region the nid is not set > > > > it is > > > > still default value MAX_NUMNODES. later node_set callback will set bit > > > > MAX_NUMNODES in nodemask bitmap thus stack corruption happen. > > > > > > > > Fixing this by adding a check, do not call node_set in case nid is > > > > MAX_NUMNODES. > > > > > > > > Signed-off-by: Dave Young <dyo...@redhat.com> > > > > --- > > > > > > Looks good to me. > > > > > > Reviewed-by: Yasuaki Ishimatsu <isimatu.yasu...@jp.fujitsu.com> > > > > > Per suggestion from Xishi Qiu, I would like to add below comment in code > > and repost > > Could I carry with your Reviewed-by line? > > > > /* In case booting with numa=off and only using part of system ram > > * ie. mem=nn[kMG] or in kdump kernel, numa_meminfo may not include all the > > * memblock.reserved memory because trim_snb_memory() reserves specific > > pages > > * for Sandy Bridge graphics. */ > > I don't think the issue is related to numa=off. If we use numa=off, > all memory ranges which are informed by e820 are managed to Node 0. > > The issue occurs when reserved memory ranges are not included > in system ram which informed by e820.
Maybe in theory it is possible that it occurs without numa=off so that numa meminfo does not include some reserved regions, but I think I can only reproduce it with numa=off. But ok, I can use the comment below instead: /* * In case booting with mem=nn[kMG] or in kdump kernel, numa_meminfo may not * include all the memblock.reserved memory ranges because trim_snb_memory() * reserves specific pages for Sandy Bridge graphics. */ Thanks Dave -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/