From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Vrabel Subject: Re: [Xen-devel] [PATCH v3 1/2] xen/pvhvm: If xen_platform_pci=0 is set don't blow up (v3). Date: Thu, 2 Jan 2014 15:09:44 +0000 Message-ID: <52C58138.1030301@citrix.com> References: <1387206250-13963-1-git-send-email-konrad.wilk@oracle.com> <1387206250-13963-2-git-send-email-konrad.wilk@oracle.com> <52B01F67.1030108@m2r.biz> <20131217145150.GC4683@phenom.dumpdata.com> <20131217212333.GA31966@phenom.dumpdata.com> <20131231143258.GA3018@phenom.dumpdata.com> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit Return-path: Received: from smtp.citrix.com ([66.165.176.89]:7787 "EHLO SMTP.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751136AbaABPJ5 (ORCPT ); Thu, 2 Jan 2014 10:09:57 -0500 In-Reply-To: <20131231143258.GA3018@phenom.dumpdata.com> Sender: linux-input-owner@vger.kernel.org List-Id: linux-input@vger.kernel.org To: Konrad Rzeszutek Wilk Cc: Fabio Fantoni , axboe@kernel.dk, leosilva@linux.vnet.ibm.com, linux-fbdev@vger.kernel.org, dmitry.torokhov@gmail.com, ian.campbell@citrix.com, stefano.stabellini@eu.citrix.com, linux-pci@vger.kernel.org, netdev@vger.kernel.org, ashley@ashleylai.com, tpmdd@selhorst.net, linux-kernel@vger.kernel.org, mail@srajiv.net, tpmdd-devel@lists.sourceforge.net, tomi.valkeinen@ti.com, david.vrabel@citrix.com, linux-input@vger.kernel.org, bhelgaas@google.com, xen-devel@lists.xenproject.org, boris.ostrovsky@oracle.com, plagnioj@jcrosoft.com, peterhuewe@gmx.de On 31/12/13 14:32, Konrad Rzeszutek Wilk wrote: >> That is because 'disks' is incorrect. It should have been 'ide-disks' >> >> [ 0.000000] unrecognised option 'disks' in parameter 'xen_emul_unplug' >> >> With the 'ide-disks' it should work. I will update the description to >> mention 'ide-disks' instead of 'disks'. Thank you for finding this! >> > > I've v4 with said update and will push it to Linus shortly. > > Thanks! > > P.S. > Here is v4: > >>>From 275a81e7496d3532e5b4752703c50a7c8355a6c7 Mon Sep 17 00:00:00 2001 > From: Konrad Rzeszutek Wilk > Date: Tue, 26 Nov 2013 15:05:40 -0500 > Subject: [PATCH] xen/pvhvm: If xen_platform_pci=0 is set don't blow up (v4). > > The user has the option of disabling the platform driver: > 00:02.0 Unassigned class [ff80]: XenSource, Inc. Xen Platform Device (rev 01) > > which is used to unplug the emulated drivers (IDE, Realtek 8169, etc) > and allow the PV drivers to take over. If the user wishes > to disable that they can set: > > xen_platform_pci=0 > (in the guest config file) > > or > xen_emul_unplug=never > (on the Linux command line) > > except it does not work properly. The PV drivers still try to > load and since the Xen platform driver is not run - and it > has not initialized the grant tables, most of the PV drivers > stumble upon: > > input: Xen Virtual Keyboard as /devices/virtual/input/input5 > input: Xen Virtual Pointer as /devices/virtual/input/input6M > ------------[ cut here ]------------ > kernel BUG at /home/konrad/ssd/konrad/linux/drivers/xen/grant-table.c:1206! > invalid opcode: 0000 [#1] SMP > Modules linked in: xen_kbdfront(+) xenfs xen_privcmd > CPU: 6 PID: 1389 Comm: modprobe Not tainted 3.13.0-rc1upstream-00021-ga6c892b-dirty #1 > Hardware name: Xen HVM domU, BIOS 4.4-unstable 11/26/2013 > RIP: 0010:[] [] get_free_entries+0x2e0/0x300 > Call Trace: > [] ? evdev_connect+0x1e3/0x240 > [] gnttab_grant_foreign_access+0x2e/0x70 > [] xenkbd_connect_backend+0x41/0x290 [xen_kbdfront] > [] xenkbd_probe+0x2f2/0x324 [xen_kbdfront] > [] xenbus_dev_probe+0x77/0x130 > [] xenbus_frontend_dev_probe+0x47/0x50 > [] driver_probe_device+0x89/0x230 > [] __driver_attach+0x9b/0xa0 > [] ? driver_probe_device+0x230/0x230 > [] ? driver_probe_device+0x230/0x230 > [] bus_for_each_dev+0x8c/0xb0 > [] driver_attach+0x19/0x20 > [] bus_add_driver+0x1a0/0x220 > [] driver_register+0x5f/0xf0 > [] xenbus_register_driver_common+0x15/0x20 > [] xenbus_register_frontend+0x23/0x40 > [] ? 0xffffffffa0014fff > [] xenkbd_init+0x2b/0x1000 [xen_kbdfront] > [] do_one_initcall+0x49/0x170 > > .. snip.. > > which is hardly nice. This patch fixes this by having each > PV driver check for: > - if running in PV, then it is fine to execute (as that is their > native environment). > - if running in HVM, check if user wanted 'xen_emul_unplug=never', > in which case bail out and don't load any PV drivers. > - if running in HVM, and if PCI device 5853:0001 (xen_platform_pci) > does not exist, then bail out and not load PV drivers. > - (v2) if running in HVM, and if the user wanted 'xen_emul_unplug=ide-disks', > then bail out for all PV devices _except_ the block one. > Ditto for the network one ('nics'). > - (v2) if running in HVM, and if the user wanted 'xen_emul_unplug=unnecessary' > then load block PV driver, and also setup the legacy IDE paths. > In (v3) make it actually load PV drivers. [...] > --- a/arch/x86/xen/platform-pci-unplug.c > +++ b/arch/x86/xen/platform-pci-unplug.c > @@ -69,6 +69,80 @@ static int check_platform_magic(void) > return 0; > } > > +bool xen_has_pv_devices() > +{ > + if (!xen_domain()) > + return false; > + > + /* PV domains always have them. */ > + if (xen_pv_domain()) > + return true; > + > + /* And user has xen_platform_pci=0 set in guest config as > + * driver did not modify the value. */ > + if (xen_platform_pci_unplug == 0) > + return false; > + > + if (xen_platform_pci_unplug & XEN_UNPLUG_NEVER) > + return false; > + > + if (xen_platform_pci_unplug & XEN_UNPLUG_ALL) > + return true; > + > + /* This is an odd one - we are going to run legacy > + * and PV drivers at the same time. */ > + if (xen_platform_pci_unplug & XEN_UNPLUG_UNNECESSARY) > + return true; > + > + /* And the caller has to follow with xen_pv_{disk,nic}_devices > + * to be certain which driver can load. */ > + return false; This may result in: xen_has_pv_devices() == false xen_has_pv_disk_devices() == true which looks odd to me. Surely xen_has_pv_*_devices() is a subset of xen_has_pv_devices()? David