From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1LUGqV-0005VA-QM for qemu-devel@nongnu.org; Tue, 03 Feb 2009 03:41:27 -0500 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1LUGqT-0005UH-NS for qemu-devel@nongnu.org; Tue, 03 Feb 2009 03:41:27 -0500 Received: from [199.232.76.173] (port=49748 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1LUGqT-0005U7-HU for qemu-devel@nongnu.org; Tue, 03 Feb 2009 03:41:25 -0500 Received: from mtaout01-winn.ispmail.ntl.com ([81.103.221.47]:22363) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1LUGqS-0000sN-2p for qemu-devel@nongnu.org; Tue, 03 Feb 2009 03:41:24 -0500 Message-ID: <4988032A.5010905@ntlworld.com> Date: Tue, 03 Feb 2009 08:41:14 +0000 From: Mark Marshall MIME-Version: 1.0 References: <497E1B15.2090908@msgid.tls.msk.ru> <497E1F7D.90300@msgid.tls.msk.ru> <49876547.1080904@cisco.com> <49876678.4090808@msgid.tls.msk.ru> <4987674E.9050201@cisco.com> <4987FCBA.7020104@msgid.tls.msk.ru> In-Reply-To: <4987FCBA.7020104@msgid.tls.msk.ru> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: [Qemu-devel] Re: more about serial ports: do they even work? Reply-To: qemu-devel@nongnu.org List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Michael Tokarev Cc: KVM list , "David S. Ahern" , qemu-devel@nongnu.org Michael Tokarev wrote: > David S. Ahern wrote: >> Michael Tokarev wrote: >>> David S. Ahern wrote: >>>> I don't recall seeing a followup to this post. >>>> >>>> To put Michael's second suggestion into patch form, the following fixes >>>> the problem for me: >>>> >>>> --- kvm-81.orig/qemu/qemu-char.c 2008-12-14 06:16:27.000000000 -0700 >>>> +++ kvm-81/qemu/qemu-char.c 2009-02-02 14:12:20.000000000 -0700 >>>> @@ -1078,20 +1078,21 @@ >>>> if (sarg | TIOCM_DTR) >>>> *targ |= CHR_TIOCM_DTR; >>>> if (sarg | TIOCM_RTS) >>>> *targ |= CHR_TIOCM_RTS; >>>> } >>>> break; >>>> case CHR_IOCTL_SERIAL_SET_TIOCM: >>>> { >>>> int sarg = *(int *)arg; >>>> int targ = 0; >>>> + ioctl(s->fd_in, TIOCMGET, &targ); >>> here, one more operation is necessary: >>> targ &= ~(TIOCM_DTR|TIOCM_RTS); >> Interesting. that change was not needed to fix my problem. > > It just means you (or, rather, your guests) never really needed to > DROP those signal lines, only to raise them. > >>>> if (sarg | CHR_TIOCM_DTR) >>>> targ |= TIOCM_DTR; >>>> if (sarg | CHR_TIOCM_RTS) >>>> targ |= TIOCM_RTS; Is this code really correct. If it is is there a comment somewhere describing why it's correct? I would have expected the lines above to be: if (sarg & CHR_TIOCM_DTR) targ |= TIOCM_DTR; if (sarg & CHR_TIOCM_RTS) targ |= TIOCM_RTS; (Just an observation as this went past). MM > > Without that line above, the code never drops the two bits, once > set they can't be "removed" anymore. > > By the way, this is upstream qemu issue, not kvm one, and has to be > pushed as such. Good you CC'd qemu list. > > /mjt > -- > 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 >