From: "Richard W.M. Jones" <rjones@redhat.com>
To: qemu-devel@nongnu.org
Subject: [Qemu-devel] How to capture guest %rip from a qemu process without monitor?
Date: Fri, 30 Sep 2011 08:42:51 +0100 [thread overview]
Message-ID: <20110930074251.GA3972@amd.home.annexia.org> (raw)
I've finally managed to reproduce a very infrequent kernel boot hang
by forcing TCG (so it runs slower, bug seems to be timing sensitive)
and running a boot test in a loop thousands of times.
I'd like to find out where in the guest kernel this is looping.
Unfortunately I don't have access to the monitor so "info registers"
won't work, but I can attach to the qemu process with gdb.
Which TCG struct contains %rip, other registers? What other useful
information can be captured using only gdb?
Rich.
https://bugzilla.redhat.com/show_bug.cgi?id=723822
Command line:
qemu-kvm -machine pc,accel=tcg -drive file=/dev/null,if=virtio
-nodefconfig -nodefaults -nographic -m 500 -no-reboot -no-hpet -device
virtio-serial -serial stdio -chardev
socket,path=/home/rjones/d/libguestfs/libguestfsoFRvo0/guestfsd.sock,id=channel0
-device virtserialport,chardev=channel0,name=org.libguestfs.channel.0
-kernel /home/rjones/d/libguestfs/.guestfs-500/kernel.27140 -initrd
/home/rjones/d/libguestfs/.guestfs-500/initrd.27140 -append 'panic=1
console=ttyS0 udevtimeout=300 no_timer_check acpi=off printk.time=1
cgroup_disable=memory selinux=0 guestfs_verbose=1 TERM=xterm' -drive
file=/home/rjones/d/libguestfs/.guestfs-500/root.27140,snapshot=on,if=virtio,cache=unsafe
--
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
New in Fedora 11: Fedora Windows cross-compiler. Compile Windows
programs, test, and build Windows installers. Over 70 libraries supprt'd
http://fedoraproject.org/wiki/MinGW http://www.annexia.org/fedora_mingw
next reply other threads:[~2011-09-30 7:42 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-09-30 7:42 Richard W.M. Jones [this message]
2011-09-30 8:49 ` [Qemu-devel] How to capture guest %rip from a qemu process without monitor? Jan Kiszka
2011-09-30 9:03 ` Richard W.M. Jones
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