qemu-ppc
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Qemu-ppc] ppc64 TCG emulation broken


From: David Gibson
Subject: Re: [Qemu-ppc] ppc64 TCG emulation broken
Date: Thu, 29 Sep 2016 17:47:15 +1000
User-agent: Mutt/1.7.0 (2016-08-17)

On Thu, Sep 29, 2016 at 12:41:04PM +0530, Bharata B Rao wrote:
> Hi,
> 
> I am observing a kernel crash with ppc64 TCG guest on x86 and git
> bisect points to this commit:
> 
> e7b1e06fbcb81ac66e2586214a6c42fdf15fadf3
> [target-ppc: add vector insert instructions]
> 
> I hit the following guest kernel panic during boot:
> 
>          Starting Switch Root...
> [   76.632260] systemd-journald[113]: Received SIGTERM from PID 1 (systemd).
> [   77.082688] systemd-cgroups[1143]: unhandled signal 4 at
> 00003fff85d3d718 nip 00003fff85d3d718 lr 00003fff85c8c274 code 30001
> [   77.479368] systemd-coredum[1144]: unhandled signal 4 at
> 00003fff948bd718 nip 00003fff948bd718 lr 00003fff9480c274 code 30001
> [   77.479860] audit_printk_skb: 39 callbacks suppressed
> [   77.479988] audit: type=1701 audit(1475132719.390:35):
> auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=1144
> comm="systemd-coredum" exe="/usr/lib/systemd/systemd-coredump" sig=4
> [   77.485034] Process 1144(systemd-coredum) has RLIMIT_CORE set to 1
> [   77.485156] Aborting core
> [   77.858307] systemd[1]: unhandled signal 4 at 00003fff9a48d718 nip
> 00003fff9a48d718 lr 00003fff9a3dc274 code 30001
> [   77.858868] audit: type=1701 audit(1475132719.770:36):
> auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=1
> comm="systemd" exe="/usr/lib/systemd/systemd" sig=4
> [   78.004191] systemd-coredum[1145]: unhandled signal 4 at
> 00003fffa475d718 nip 00003fffa475d718 lr 00003fffa46ac274 code 30001
> [   78.004648] audit: type=1701 audit(1475132719.910:37):
> auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=1145
> comm="systemd-coredum" exe="/usr/lib/systemd/systemd-coredump" sig=4
> [   78.004971] Process 1145(systemd-coredum) has RLIMIT_CORE set to 1
> [   78.005066] Aborting core
> [   78.015142] Kernel panic - not syncing: Attempted to kill init!
> exitcode=0x00000084
> [   78.015142]
> [   78.016926] CPU: 0 PID: 1 Comm: systemd Not tainted 4.6.4-301.fc24.ppc64 #1
> [   78.017726] Call Trace:
> [   78.019154] [c00000007e6638d0] [c0000000009df0f0]
> .dump_stack+0xa8/0xe8 (unreliable)
> [   78.022485] [c00000007e663960] [c0000000009dd6bc] .panic+0x12c/0x2fc
> [   78.022631] [c00000007e663a00] [c0000000000cd6a8] .do_exit+0xca8/0xcb0
> [   78.022735] [c00000007e663ae0] [c0000000000cd77c] .do_group_exit+0x5c/0xf0
> [   78.022815] [c00000007e663b70] [c0000000000dd4ec] .get_signal+0x3bc/0x770
> [   78.022918] [c00000007e663c70] [c00000000001761c] .do_signal+0x4c/0x2a0
> [   78.023021] [c00000007e663db0] [c000000000017a4c] 
> .do_notify_resume+0xac/0xc0
> [   78.023411] [c00000007e663e30] [c000000000009944]
> .ret_from_except_lite+0x70/0x74
> [   78.077889] ---[ end Kernel panic - not syncing: Attempted to kill
> init! exitcode=0x00000084

Huh.  Well, that's unfortunate.  I don't imagine the guest is trying
to use any of those new POWER9 instructions, so I guess we must have
broken decode of one of the existing vector instructions with which it
shares some part of the opcode.

Any chance you could trace this and work out what instruction is
giving the first illegal instruction exception?

-- 
David Gibson                    | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au  | minimalist, thank you.  NOT _the_ _other_
                                | _way_ _around_!
http://www.ozlabs.org/~dgibson

Attachment: signature.asc
Description: PGP signature


reply via email to

[Prev in Thread] Current Thread [Next in Thread]