From c93a4dfb31f2c023da3ad1238c352452f2cc0e05 Mon Sep 17 00:00:00 2001 From: Ian Campbell Date: Mon, 23 Aug 2010 11:59:28 +0100 Subject: xen: pvhvm: allow user to request no emulated device unplug this allows the user to disable pvhvm and revert to emulated devices in case of a system misconfiguration (e.g. initramfs with only emulated drivers in it). Signed-off-by: Ian Campbell Acked-by: Jeremy Fitzhardinge Acked-by: Stefano Stabellini --- arch/x86/xen/platform-pci-unplug.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'arch/x86') diff --git a/arch/x86/xen/platform-pci-unplug.c b/arch/x86/xen/platform-pci-unplug.c index 554c002a1e1a..070dfa0654bd 100644 --- a/arch/x86/xen/platform-pci-unplug.c +++ b/arch/x86/xen/platform-pci-unplug.c @@ -72,6 +72,9 @@ void __init xen_unplug_emulated_devices(void) { int r; + /* user explicitly requested no unplug */ + if (xen_emul_unplug & XEN_UNPLUG_NEVER) + return; /* check the version of the xen platform PCI device */ r = check_platform_magic(); /* If the version matches enable the Xen platform PCI driver. @@ -127,6 +130,8 @@ static int __init parse_xen_emul_unplug(char *arg) xen_emul_unplug |= XEN_UNPLUG_ALL_NICS; else if (!strncmp(p, "ignore", l)) xen_emul_unplug |= XEN_UNPLUG_IGNORE; + else if (!strncmp(p, "never", l)) + xen_emul_unplug |= XEN_UNPLUG_NEVER; else printk(KERN_WARNING "unrecognised option '%s' " "in parameter 'xen_emul_unplug'\n", p); -- cgit v1.2.3 From 1dc7ce99b091a11cce0f34456c1ffcb928f17edd Mon Sep 17 00:00:00 2001 From: Ian Campbell Date: Mon, 23 Aug 2010 11:59:29 +0100 Subject: xen: pvhvm: rename xen_emul_unplug=ignore to =unnnecessary It is not immediately clear what this option causes to become ignored. The actual meaning is that it is not necessary to unplug the emulated devices to safely use the PV ones, even if the platform does not support the unplug protocol. (pressumably the user will only add this option if they have ensured that their domain configuration is safe). I think xen_emul_unplug=unnecessary better captures this. Signed-off-by: Ian Campbell Acked-by: Jeremy Fitzhardinge Acked-by: Stefano Stabellini --- arch/x86/xen/platform-pci-unplug.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) (limited to 'arch/x86') diff --git a/arch/x86/xen/platform-pci-unplug.c b/arch/x86/xen/platform-pci-unplug.c index 070dfa0654bd..0f456386cce5 100644 --- a/arch/x86/xen/platform-pci-unplug.c +++ b/arch/x86/xen/platform-pci-unplug.c @@ -78,10 +78,11 @@ void __init xen_unplug_emulated_devices(void) /* check the version of the xen platform PCI device */ r = check_platform_magic(); /* If the version matches enable the Xen platform PCI driver. - * Also enable the Xen platform PCI driver if the version is really old - * and the user told us to ignore it. */ + * Also enable the Xen platform PCI driver if the host does + * not support the unplug protocol (XEN_PLATFORM_ERR_MAGIC) + * but the user told us that unplugging is unnecessary. */ if (r && !(r == XEN_PLATFORM_ERR_MAGIC && - (xen_emul_unplug & XEN_UNPLUG_IGNORE))) + (xen_emul_unplug & XEN_UNPLUG_UNNECESSARY))) return; /* Set the default value of xen_emul_unplug depending on whether or * not the Xen PV frontends and the Xen platform PCI driver have @@ -102,7 +103,7 @@ void __init xen_unplug_emulated_devices(void) } } /* Now unplug the emulated devices */ - if (!(xen_emul_unplug & XEN_UNPLUG_IGNORE)) + if (!(xen_emul_unplug & XEN_UNPLUG_UNNECESSARY)) outw(xen_emul_unplug, XEN_IOPORT_UNPLUG); xen_platform_pci_unplug = xen_emul_unplug; } @@ -128,8 +129,8 @@ static int __init parse_xen_emul_unplug(char *arg) xen_emul_unplug |= XEN_UNPLUG_AUX_IDE_DISKS; else if (!strncmp(p, "nics", l)) xen_emul_unplug |= XEN_UNPLUG_ALL_NICS; - else if (!strncmp(p, "ignore", l)) - xen_emul_unplug |= XEN_UNPLUG_IGNORE; + else if (!strncmp(p, "unnecessary", l)) + xen_emul_unplug |= XEN_UNPLUG_UNNECESSARY; else if (!strncmp(p, "never", l)) xen_emul_unplug |= XEN_UNPLUG_NEVER; else -- cgit v1.2.3