From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1LNdTS-0007i9-Hh for qemu-devel@nongnu.org; Thu, 15 Jan 2009 20:26:14 -0500 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1LNdTQ-0007hl-Fp for qemu-devel@nongnu.org; Thu, 15 Jan 2009 20:26:14 -0500 Received: from [199.232.76.173] (port=53395 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1LNdTQ-0007hi-By for qemu-devel@nongnu.org; Thu, 15 Jan 2009 20:26:12 -0500 Received: from mx20.gnu.org ([199.232.41.8]:46329) by monty-python.gnu.org with esmtps (TLS-1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1LNdTP-0005FY-Ta for qemu-devel@nongnu.org; Thu, 15 Jan 2009 20:26:12 -0500 Received: from sj-iport-6.cisco.com ([171.71.176.117]) by mx20.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1LNdTL-0007tg-Ey for qemu-devel@nongnu.org; Thu, 15 Jan 2009 20:26:07 -0500 Received: from sj-core-4.cisco.com (sj-core-4.cisco.com [171.68.223.138]) by sj-dkim-1.cisco.com (8.12.11/8.12.11) with ESMTP id n0G1Pu7I012435 for ; Thu, 15 Jan 2009 17:25:56 -0800 Received: from xbh-sjc-211.amer.cisco.com (xbh-sjc-211.cisco.com [171.70.151.144]) by sj-core-4.cisco.com (8.13.8/8.13.8) with ESMTP id n0G1Pu9p029875 for ; Fri, 16 Jan 2009 01:25:56 GMT Message-ID: <496FE222.3080704@cisco.com> Date: Thu, 15 Jan 2009 18:25:54 -0700 From: "David S. Ahern" MIME-Version: 1.0 References: <494FA255.9010702@cisco.com> In-Reply-To: <494FA255.9010702@cisco.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Subject: [Qemu-devel] RESEND: qemu spinning on serial port writes Reply-To: qemu-devel@nongnu.org List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org I sent this right before the holidays, and I have not seen any response. Has anyone had success connecting guest serial port to host serial port directly with guest boot output streaming out? david David S. Ahern wrote: > I am trying to redirect a guest's boot output through the host's serial > port. Shortly after launching qemu, the main thread is spinning on: > > write(9, "0", 1) = -1 EAGAIN (Resource temporarily unavailable) > > fd 9 is the serial port, ttyS0. > > > The backtrace for the thread is: > > #0 0x00002ac3433f8c0b in write () from /lib64/libpthread.so.0 > #1 0x0000000000475df9 in send_all (fd=9, buf=, > len1=1) at qemu-char.c:477 > #2 0x000000000043a102 in serial_xmit (opaque=) at > /root/kvm-81/qemu/hw/serial.c:311 > #3 0x000000000043a591 in serial_ioport_write (opaque=0x14971790, > addr=, val=48) > at /root/kvm-81/qemu/hw/serial.c:366 > #4 0x00000000410eeedc in ?? () > #5 0x0000000000129000 in ?? () > #6 0x0000000014821fa0 in ?? () > #7 0x0000000000000007 in ?? () > #8 0x00000000004a54c5 in tlb_set_page_exec (env=0x10ab4, > vaddr=46912496956816, paddr=1, prot=-1, mmu_idx=0, is_softmmu=1) > at /root/kvm-81/qemu/exec.c:388 > #9 0x0000000000512f3b in tlb_fill (addr=345446292, is_write=1, > mmu_idx=-1, retaddr=0x0) > at /root/kvm-81/qemu/target-i386/op_helper.c:4690 > #10 0x00000000004a6bd2 in __ldb_cmmu (addr=9, mmu_idx=0) at > /root/kvm-81/qemu/softmmu_template.h:135 > #11 0x00000000004a879b in cpu_x86_exec (env1=) at > /root/kvm-81/qemu/cpu-exec.c:628 > #12 0x000000000040ba29 in main (argc=12, argv=0x7fff67f7a398) at > /root/kvm-81/qemu/vl.c:3816 > > send_all() invokes unix_write() which by design is not breaking out on > EAGAIN. > > The following command is enough to show the problem: > > qemu-system-x86_64 -m 256 -smp 1 -no-kvm \ > -drivefile=/dev/cciss/c0d0,if=scsi,cache=off,boot=on \ > -vnc :1 -serial /dev/ttyS0 > > > The guest is running RHEL3 with the parameter 'console=ttyS0' added to > grub.conf; the problem appears to be with qemu, so I would expect it to > show with any linux guest. This particular host is running RHEL5.2 with > kvm-81, but I have also seen the problem with Fedora-9 as the host OS. > > Yes, the serial port of the server is connected to another system via a > null modem. If I change the serial argument to '-serial udp::4555' and > use 'nc -u -l localhost 4555 > /dev/ttyS0' I see the guest's boot > output show up on the second system as expected. I'd prefer to be able > to use the serial port connection directly without nc as a proxy. > Suggestions? > > david > -- > To unsubscribe from this list: send the line "unsubscribe kvm" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >