On 2016-07-24 05:36, Marc Zyngier wrote: > On Sun, 24 Jul 2016 13:22:55 +0100 > Marc Zyngier <marc.zyngier@xxxxxxx> wrote: > >> On Fri, 22 Jul 2016 10:56:44 -0700 >> Stefan Agner <stefan@xxxxxxxx> wrote: >> >> > On 2016-07-22 10:49, Marc Zyngier wrote: >> > > On 22/07/16 18:38, Andrew Jones wrote: >> > >> On Fri, Jul 22, 2016 at 04:40:15PM +0100, Marc Zyngier wrote: >> > >>> On 22/07/16 15:35, Andrew Jones wrote: >> > >>>> On Fri, Jul 22, 2016 at 11:42:02AM +0100, Andre Przywara wrote: >> > >>>>> Hi Stefan, >> > >>>>> >> > >>>>> On 22/07/16 06:57, Stefan Agner wrote: >> > >>>>>> Hi, >> > >>>>>> >> > >>>>>> I tried KVM on a Cortex-A7 platform (i.MX 7Dual SoC) and encountered >> > >>>>>> this stack trace immediately after invoking qemu-system-arm: >> > >>>>>> >> > >>>>>> Unable to handle kernel paging request at virtual address ffffffe4 >> > >>>>>> pgd = 8ca52740 >> > >>>>>> [ffffffe4] *pgd=80000080007003, *pmd=8ff7e003, *pte=00000000 >> > >>>>>> Internal error: Oops: 207 [#1] SMP ARM >> > >>>>>> Modules linked in: >> > >>>>>> CPU: 0 PID: 329 Comm: qemu-system-arm Tainted: G W >> > >>>>>> 4.7.0-rc7-00094-gea3ed2c #109 >> > >>>>>> Hardware name: Freescale i.MX7 Dual (Device Tree) >> > >>>>>> task: 8ca3ee40 ti: 8d2b0000 task.ti: 8d2b0000 >> > >>>>>> PC is at do_raw_spin_lock+0x8/0x1dc >> > >>>>>> LR is at kvm_vgic_flush_hwstate+0x8c/0x224 >> > >>>>>> pc : [<8027c87c>] lr : [<802172d4>] psr: 60070013 >> > >>>>>> sp : 8d2b1e38 ip : 8d2b0000 fp : 00000001 >> > >>>>>> r10: 8d2b0000 r9 : 00010000 r8 : 8d2b8e54 >> > >>>>>> fec 30be0000.ethernet eth0: MDIO read timeout >> > >>>>>> r7 : 8d2b8000 r6 : 8d2b8e74 r5 : 00000000 r4 : ffffffe0 >> > >>>>>> r3 : 00004ead r2 : 00000000 r1 : 00000000 r0 : ffffffe0 >> > >>>>>> Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user >> > >>>>>> Control: 30c5387d Table: 8ca52740 DAC: fffffffd >> > >>>>>> Process qemu-system-arm (pid: 329, stack limit = 0x8d2b0210) >> > >>>>>> Stack: (0x8d2b1e38 to 0x8d2b2000) >> > >>>>>> 1e20: ffffffe0 >> > >>>>>> 00000000 >> > >>>>>> 1e40: 8d2b8e74 8d2b8000 8d2b8e54 00010000 8d2b0000 802172d4 8d2b8000 >> > >>>>>> 810074f8 >> > >>>>>> 1e60: 81007508 8ca5f800 8d284000 00010000 8d2b0000 8020fbd4 8ce9a000 >> > >>>>>> 8ca5f800 >> > >>>>>> 1e80: 00000000 00010000 00000000 00ff0000 8d284000 00000000 00000000 >> > >>>>>> 7ffbfeff >> > >>>>>> 1ea0: fffffffe 00000000 8d28b780 00000000 755fec6c 00000000 00000000 >> > >>>>>> ffffe000 >> > >>>>>> 1ec0: 8d2b8000 00000000 8d28b780 00000000 755fec6c 8020af90 00000000 >> > >>>>>> 8023f248 >> > >>>>>> 1ee0: 0000000a 755fe98c 8d2b1f08 00000008 8021aa84 ffffe000 00000000 >> > >>>>>> 00000000 >> > >>>>>> 1f00: 8a00d860 8d28b780 80334f94 00000000 8d2b0000 80334748 00000000 >> > >>>>>> 00000000 >> > >>>>>> 1f20: 00000000 8d28b780 00004000 00000009 8d28b500 00000024 8104ebee >> > >>>>>> 80bc2ec4 >> > >>>>>> 1f40: 80bafa24 8034138c 00000000 00000000 80341248 00000000 755fec6c >> > >>>>>> 007c1e70 >> > >>>>>> 1f60: 00000009 00004258 0000ae80 8d28b781 00000009 8d28b780 0000ae80 >> > >>>>>> 00000000 >> > >>>>>> 1f80: 8d2b0000 00000000 755fec6c 80334f94 007c1e70 322a7400 00004258 >> > >>>>>> 00000036 >> > >>>>>> 1fa0: 8021aa84 8021a900 007c1e70 322a7400 00000009 0000ae80 00000000 >> > >>>>>> 755feac0 >> > >>>>>> 1fc0: 007c1e70 322a7400 00004258 00000036 7e9aff58 01151da4 76f8b4c0 >> > >>>>>> 755fec6c >> > >>>>>> 1fe0: 0038192c 755fea9c 00048ae7 7697d66c 60070010 00000009 00000000 >> > >>>>>> 00000000 >> > >>>>>> [<8027c87c>] (do_raw_spin_lock) from [<802172d4>] >> > >>>>>> (kvm_vgic_flush_hwstate+0x8c/0x224) >> > >>>>>> [<802172d4>] (kvm_vgic_flush_hwstate) from [<8020fbd4>] >> > >>>>>> (kvm_arch_vcpu_ioctl_run+0x110/0x478) >> > >>>>>> [<8020fbd4>] (kvm_arch_vcpu_ioctl_run) from [<8020af90>] >> > >>>>>> (kvm_vcpu_ioctl+0x2e0/0x6d4) >> > >>>>>> [<8020af90>] (kvm_vcpu_ioctl) from [<80334748>] >> > >>>>>> (do_vfs_ioctl+0xa0/0x8b8) >> > >>>>>> [<80334748>] (do_vfs_ioctl) from [<80334f94>] (SyS_ioctl+0x34/0x5c) >> > >>>>>> [<80334f94>] (SyS_ioctl) from [<8021a900>] (ret_fast_syscall+0x0/0x1c) >> > >>>>>> Code: e49de004 ea09ea24 e92d47f0 e3043ead (e5902004) >> > >>>>>> ---[ end trace cb88537fdc8fa206 ]--- >> > >>>>>> >> > >>>>>> I use CONFIG_KVM_NEW_VGIC=y. This happens to me with a rather minimal >> > >>>>>> qemu invocation (qemu-system-arm -enable-kvm -M virt -cpu host >> > >>>>>> -nographic -serial stdio -kernel zImage). >> > >>>>>> >> > >>>>>> Using a bit older Qemu version 2.4.0. >> > >>>>> >> > >>>>> I just tried with a self compiled QEMU 2.4.0 and the Ubuntu 14.04 >> > >>>>> provided 2.0.0, it worked fine with Linus' current HEAD as a host kernel >> > >>>>> on a Midway (Cortex-A15). >> > >>>> >> > >>>> I can reproduce the issue with a latest QEMU build on AMD Seattle >> > >>>> (I haven't tried anywhere else yet) >> > >>>> >> > >>>>> >> > >>>>> Can you try to disable the new VGIC, just to see if that's a regression? >> > >>>> >> > >>>> Disabling NEW_VGIC "fixes" guest boots. >> > >>>> >> > >>>> I'm not using defconfig for my host kernel. I'll do a couple more >> > >>>> tests and provide a comparison of my config vs. a defconfig in >> > >>>> a few minutes. >> > >>> >> > >>> Damn. It is not failing for me, so it has to be a kernel config thing... >> > >>> If you can narrow it down to the difference with defconfig, that'd be >> > >>> tremendously helpful. >> > >> >> > >> It's PAGE_SIZE; 64K doesn't work, 4K does, regardless of VA_BITS >> > >> selection. >> > > >> > > That definitely doesn't match Stefan's report (32bit only has 4k). I'll >> > >> > Hehe, was just plowing through code and came to that conclusion, glad I >> > got that right :-) >> > >> > What defconfig do you use? I could reproduce the issue also with >> > multi_v7_defconfig + ARM_LPAE + KVM. >> >> I'm now on -rc7 with multi_v7_defconfig + LPAE + KVM (and everything >> built-in to make my life simpler). The host works perfectly, and I can >> spawn VMs without any issue. >> >> I've tested with QEMU emulator version 2.2.0 (Debian 1:2.2+dfsg-5exp) >> as packaged with Jessie from a while ago. I've also upgraded the box to >> something more recent (2.5), same effect. >> >> > >> > Btw, I am not exactly on vanilla 4.7-rc7, I merged Shawns for-next + >> > clock next to get to the bits and pieces required for my board... >> > >> > That said, it works fine otherwise, and the stacktrace looks rather >> > platform independent... >> >> Indeed, and if these clocks were doing anything unsavoury, we'd >> probably see other things exploding. So we need to find out where we >> are diverging. >> >> What compiler are you using? I just noticed that my build >> infrastructure is a bit outdated for 32bit ARM (gcc 4.9.2), so I'm >> going to upgrade that to gcc 5.3 and retest. As you expected, the clock fix did not influence this problem. Still the same. I ran strace several times, the crash seems to happen always about the same time, maybe this gives you a hint? ioctl(9, KVM_CHECK_EXTENSION or LOGGER_GET_NEXT_ENTRY_LEN, 0x10) = 1 mmap2(NULL, 2101248, PROT_NONE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xa3bff000 mmap2(0xa3c00000, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0xa3c00000 munmap(0xa3bff000, 4096) = 0 munmap(0xa3c02000, 2088960) = 0 madvise(0xa3c00000, 4096, MADV_MERGEABLE) = -1 EINVAL (Invalid argument) madvise(0xa3c00000, 4096, MADV_HUGEPAGE) = -1 EINVAL (Invalid argument) madvise(0xa3c00000, 4096, MADV_DONTFORK) = 0 ioctl(9, KVM_CHECK_EXTENSION or LOGGER_GET_NEXT_ENTRY_LEN, 0x10) = 1 futex(0x9afe3c, FUTEX_CMP_REQUEUE_PRIVATE, 1, 2147483647, 0x4957a8, 4) = 1 tgkill(450, 452, SIGUSR1) = 0 futex(0x4957a8, FUTEX_WAKE_PRIVATE, 1) = 1 futex(0x4956a8, FUTEX_WAKE_PRIVATE, 1) = 1 futex(0x4956ac, FUTEX_WAIT_PRIVATE, 3, NULL) = -1 EAGAIN (Resource temporarily unavailable) ioctl(11, KVM_ARM_VCPU_INIT, 0xbe8be99c) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 ioctl(11, KVM_ARM_SET_DEVICE_ADDR or KVM_GET_ONE_REG, 0xbe8be998) = 0 [ 20.383970] Unable to handle kernel paging request at virtual address fffffffc ... -- Stefan _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
