From: Borislav Petkov <bp@alien8.de>
To: kvm@vger.kernel.org
Cc: Paolo Bonzini <pbonzini@redhat.com>,
lkml <linux-kernel@vger.kernel.org>,
qemu-devel@nongnu.org
Subject: Re: freeze host when injecting NMIs in the guest, at least in 4.4-rc4+
Date: Thu, 10 Dec 2015 17:44:07 +0100 [thread overview]
Message-ID: <20151210164407.GA3593@nazgul.tnic> (raw)
In-Reply-To: <20151210162733.GA6587@pd.tnic>
Yap,
this is clearly a qemu/kvm issue. Lemme remove ext4 folks from CC. So
here's what happens:
I boot a kvm guest, connect to its monitor (qemu is started with
"-monitor pty") and on the monitor I issue a couple of times the "nmi"
command. It doesn't explode immediately but it happens pretty often and
when it happens, the *host*(!) freezes with some nasty corruption, see
below.
Thoughts, suggestions, ideas?
...
[ 13.564192] IPv6: ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready
[ 111.524485] kvm: zapping shadow pages for mmio generation wraparound
[ 166.414836] EXT4-fs (sdb1): mounted filesystem with ordered data mode. Opts: (null)
[ 172.408126] kvm: zapping shadow pages for mmio generation wraparound
[ 200.912827] BUG: unable to handle kernel NULL pointer dereference at (null)
[ 200.920716] IP: [< (null)>] (null)
[ 200.925796] PGD 0
[ 200.927833] Oops: 0010 [#1] PREEMPT SMP
[ 200.931258] Modules linked in: binfmt_misc ipv6 vfat fat fuse dm_crypt dm_mod kvm_amd kvm irqq
[ 200.931274] CPU: 0 PID: 3936 Comm: qemu-system-x86 Not tainted 4.4.0-rc4+ #1
[ 200.931275] Hardware name: To be filled by O.E.M. To be filled by O.E.M./M5A97 EVO R2.0, BIOS3
[ 200.931276] task: ffff880037ba0000 ti: ffff8804227d8000 task.ti: ffff8804227d8000
[ 200.931277] RIP: 0010:[<0000000000000000>] [< (null)>] (null)
[ 200.931278] RSP: 0018:ffff8804227dbcb0 EFLAGS: 00010292
[ 200.931278] RAX: ffff880037ba0000 RBX: 0000000000000292 RCX: 0000000000000003
[ 200.931279] RDX: ffff880037ba0750 RSI: 0000000000000000 RDI: ffff880037ba0001
[ 200.931280] RBP: ffff8804227dbd08 R08: 0000000000000001 R09: 00000011f89b6000
[ 200.931280] R10: ffffffff825c4fd0 R11: 0000000000000000 R12: 0000000000000000
[ 200.931281] R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000000
[ 200.931282] FS: 00007fec0faba700(0000) GS:ffff88042c600000(0000) knlGS:0000000000000000
[ 200.931283] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[ 200.931283] CR2: 0000000000000000 CR3: 00000000b6566000 CR4: 00000000000406f0
[ 200.931283] Stack:
[ 200.931285] ffffffff8121004e ffff880400000000 ffffffff00000000 0000000000000292
[ 200.931287] 00000000a0305d3c ffff880414612280 ffff880414612210 ffff8804227dbe90
[ 200.931288] ffff880414612130 ffff880037ba0000 ffffffff8121004e ffff8804227dbd90
[ 200.931288] Call Trace:
[ 200.931293] [<ffffffff8121004e>] ? ext4_file_write_iter+0x8e/0x470
[ 200.931295] [<ffffffff8121004e>] ? ext4_file_write_iter+0x8e/0x470
[ 200.931298] [<ffffffff816de106>] mutex_lock_nested+0x66/0x3d0
[ 200.931299] [<ffffffff8121004e>] ? ext4_file_write_iter+0x8e/0x470
[ 200.931301] [<ffffffff8121004e>] ? ext4_file_write_iter+0x8e/0x470
[ 200.931303] [<ffffffff810a916a>] ? __lock_acquire+0x55a/0x1f80
[ 200.931305] [<ffffffff8121004e>] ext4_file_write_iter+0x8e/0x470
[ 200.931307] [<ffffffff811ac78e>] ? __fget+0x11e/0x210
[ 200.931309] [<ffffffff810a2cb4>] ? percpu_down_read+0x44/0x90
[ 200.931311] [<ffffffff8118d47d>] __vfs_write+0xad/0xe0
[ 200.931313] [<ffffffff8118dcd5>] vfs_write+0xb5/0x1a0
[ 200.931315] [<ffffffff8118e912>] SyS_write+0x52/0xc0
[ 200.931317] [<ffffffff816e2d5b>] entry_SYSCALL_64_fastpath+0x16/0x6f
[ 200.931319] Code: Bad RIP value.
[ 200.931320] RIP [< (null)>] (null)
[ 200.931321] RSP <ffff8804227dbcb0>
[ 200.931321] CR2: 0000000000000000
[ 200.939353] ---[ end trace 70675f54590d7755 ]---
[ 200.939370] note: qemu-system-x86[3936] exited with preempt_count 1
--
Regards/Gruss,
Boris.
ECO tip #101: Trim your mails when you reply.
--
next parent reply other threads:[~2015-12-10 16:44 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20151210140404.GA3049@nazgul.tnic>
[not found] ` <20151210162733.GA6587@pd.tnic>
2015-12-10 16:44 ` Borislav Petkov [this message]
2015-12-10 16:49 ` freeze host when injecting NMIs in the guest, at least in 4.4-rc4+ Paolo Bonzini
2015-12-10 16:53 ` Borislav Petkov
2015-12-10 17:34 ` Paolo Bonzini
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