From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1NrpOA-000682-I3 for qemu-devel@nongnu.org; Wed, 17 Mar 2010 05:18:06 -0400 Received: from [199.232.76.173] (port=38703 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1NrpO9-00067u-Ie for qemu-devel@nongnu.org; Wed, 17 Mar 2010 05:18:05 -0400 Received: from Debian-exim by monty-python.gnu.org with spam-scanned (Exim 4.60) (envelope-from ) id 1NrpO7-00046X-Mk for qemu-devel@nongnu.org; Wed, 17 Mar 2010 05:18:05 -0400 Received: from mx1.redhat.com ([209.132.183.28]:36892) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1NrpO7-00046H-4h for qemu-devel@nongnu.org; Wed, 17 Mar 2010 05:18:03 -0400 Message-ID: <4BA09E41.7000300@redhat.com> Date: Wed, 17 Mar 2010 10:17:53 +0100 From: Gerd Hoffmann MIME-Version: 1.0 References: <4BA094FE.6020109@msgid.tls.msk.ru> In-Reply-To: <4BA094FE.6020109@msgid.tls.msk.ru> Content-Type: multipart/mixed; boundary="------------010704010608080708010901" Subject: [Qemu-devel] Re: >2 serial ports? List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Michael Tokarev Cc: "qemu-devel@nongnu.org" , KVM list This is a multi-part message in MIME format. --------------010704010608080708010901 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit On 03/17/10 09:38, Michael Tokarev wrote: > Since 0.12, it appears that kvm does not allow more than > 2 serial ports for a guest: > > $ kvm \ > -serial unix:s1,server,nowait \ > -serial unix:s2,server,nowait \ > -serial unix:s3,server,nowait > isa irq 4 already assigned > > Is there a work-around for this? Oh, well, yes, I remember. qemu is more strict on ISA irq sharing now. A bit too strict. /me goes dig out a old patch which never made it upstream for some reason I forgot. Attached. HTH, Gerd --------------010704010608080708010901 Content-Type: text/plain; name="0001-isa-refine-irq-reservations.patch" Content-Transfer-Encoding: 7bit Content-Disposition: attachment; filename="0001-isa-refine-irq-reservations.patch" >>From 7d5d53e8a23544ac6413487a8ecdd43537ade9f3 Mon Sep 17 00:00:00 2001 From: Gerd Hoffmann Date: Fri, 11 Sep 2009 13:43:46 +0200 Subject: [PATCH] isa: refine irq reservations There are a few cases where IRQ sharing on the ISA bus is used and possible. In general only devices of the same kind can do that. A few use cases: * serial lines 1+3 share irq 4 * serial lines 2+4 share irq 3 * parallel ports share irq 7 * ppc/prep: ide ports share irq 13 This patch refines the irq reservation mechanism for the isa bus to handle those cases. It keeps track of the driver which owns the IRQ in question and allows irq sharing for devices handled by the same driver. Signed-off-by: Gerd Hoffmann --- hw/isa-bus.c | 16 +++++++++++++--- 1 files changed, 13 insertions(+), 3 deletions(-) diff --git a/hw/isa-bus.c b/hw/isa-bus.c index 4d489d2..bd2f69c 100644 --- a/hw/isa-bus.c +++ b/hw/isa-bus.c @@ -26,6 +26,7 @@ struct ISABus { BusState qbus; qemu_irq *irqs; uint32_t assigned; + DeviceInfo *irq_owner[16]; }; static ISABus *isabus; @@ -71,7 +72,9 @@ qemu_irq isa_reserve_irq(int isairq) exit(1); } if (isabus->assigned & (1 << isairq)) { - fprintf(stderr, "isa irq %d already assigned\n", isairq); + DeviceInfo *owner = isabus->irq_owner[isairq]; + fprintf(stderr, "isa irq %d already assigned (%s)\n", + isairq, owner ? owner->name : "unknown"); exit(1); } isabus->assigned |= (1 << isairq); @@ -82,10 +85,17 @@ void isa_init_irq(ISADevice *dev, qemu_irq *p, int isairq) { assert(dev->nirqs < ARRAY_SIZE(dev->isairq)); if (isabus->assigned & (1 << isairq)) { - fprintf(stderr, "isa irq %d already assigned\n", isairq); - exit(1); + DeviceInfo *owner = isabus->irq_owner[isairq]; + if (owner == dev->qdev.info) { + /* irq sharing is ok in case the same driver handles both */; + } else { + fprintf(stderr, "isa irq %d already assigned (%s)\n", + isairq, owner ? owner->name : "unknown"); + exit(1); + } } isabus->assigned |= (1 << isairq); + isabus->irq_owner[isairq] = dev->qdev.info; dev->isairq[dev->nirqs] = isairq; *p = isabus->irqs[isairq]; dev->nirqs++; -- 1.6.6.1 --------------010704010608080708010901--