From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <4F7AD9BD.1070201@domain.hid> Date: Tue, 03 Apr 2012 13:06:37 +0200 From: Gilles Chanteperdrix MIME-Version: 1.0 References: <4F4150C8.7040104@domain.hid> <4F4278ED.9090802@domain.hid> <4F478285.8020105@domain.hid> <4F47A161.9010704@domain.hid> <4F79C838.2070609@domain.hid> <4F79CBAA.6040107@domain.hid> <4F7A0F11.3080504@domain.hid> <4F7A128C.4040706@domain.hid> <4F7A133E.7000505@domain.hid> <4F7A2039.2040409@domain.hid> <4F7A211F.1080809@domain.hid> <4F7AACC1.6080500@domain.hid> <4F7AADFD.3060506@domain.hid> In-Reply-To: <4F7AADFD.3060506@domain.hid> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Subject: Re: [Adeos-main] Reworking ipipe timer subsystem, List-Id: General discussion about Adeos List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Jan Kiszka Cc: Adeos , Philippe Gerum On 04/03/2012 09:59 AM, Jan Kiszka wrote: > On 2012-04-03 09:54, Gilles Chanteperdrix wrote: >> On 04/02/2012 11:58 PM, Jan Kiszka wrote: >>> On 2012-04-02 23:55, Gilles Chanteperdrix wrote: >>>> On 04/02/2012 10:59 PM, Jan Kiszka wrote: >>>>> On 2012-04-02 22:56, Jan Kiszka wrote: >>>>>>> No luck, I am using qemu 0.12.5, there is no -global option documented, >>>>>> >>>>>> Err, that's prehistoric. Use stable 1.0.x at least to receive proper >>>>>> HPET support. >>>>> >>>>> Oh, and there is one further pitfall: You need to provide >>>>> -no-kvm-irqchip to use the HPET with MSI support because qemu-kvm does >>>>> not forward those MSIs to the kernel irqchip model. I'm sitting on >>>>> patches... >>>> >>>> Yes, I needed that. It works now, except that I could not find how to >>>> use an NFS root filesystem. But with an ext3 file-backed filesystem, I >>>> could get that: >>> >>> If your NFS server runs on the host and you use userspace networking >>> (default without additional parameters), the guest should be able to >>> reach the server under 10.0.2.2 and use an IP like 10.0.2.15 (or dhcp). >>> However, I recently failed to get this working as well but didn't dig >>> deeper. >> >> Well, with -net user, I do not get any network interface on the >> simulated kernel. Maybe there a special network driver to enable in the >> kernel? The documentation does not say which network card is simulated, >> and I do not see any with lspci. > > qemu-kvm emulates a rtl8139 by default. But, by just specifying -net > user, you disable any network adapter. Just leave it out, -net user -net > nic,model=rtl8139 is default. How is -net user supposed to work if there is no emulated nic on the board. I tried -net nic first, but it did not work either, it seems to use vlans, but I do not have vlans configured on my host nor any desire to configure them. Is there not a way to simply share the host network interface with the guest, the way virtualbox does it? > >> >> Something else, is it possible to run kvm using SCHED_FIFO policy? I >> tried that and I almost got a lockup, was probably saved by throttling. > > Yes, but not without some patches and a lot of tuning on both guest and > host side. A standard Linux kernel touches too many device models that > will take a long time to make RT compatible. A simple access to a > virtual graphic adapter will be like accessing a screwed up physical GPU > with horrible latency. Yes, ok, but my main interest was the timer interrupt. Besides this does not explain why I get a lockup. > > Jan > -- Gilles.