| Message ID | 1367549230-12805-1-git-send-email-hutao@cn.fujitsu.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Il 03/05/2013 04:47, Hu Tao ha scritto: > pvpanic device is a qemu simulated device through which guest panic > event is sent to host. > > Signed-off-by: Hu Tao <hutao@cn.fujitsu.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> but you may reword the help message as hinted below. Paolo > --- > drivers/platform/x86/Kconfig | 7 +++ > drivers/platform/x86/Makefile | 2 + > drivers/platform/x86/pvpanic.c | 115 +++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 124 insertions(+) > create mode 100644 drivers/platform/x86/pvpanic.c > > diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig > index 3338437..527ed04 100644 > --- a/drivers/platform/x86/Kconfig > +++ b/drivers/platform/x86/Kconfig > @@ -781,4 +781,11 @@ config APPLE_GMUX > graphics as well as the backlight. Currently only backlight > control is supported by the driver. > > +config PVPANIC > + tristate "pvpanic device support" > + depends on ACPI > + ---help--- > + This driver provides support for pvpanic device, which is a qemu > + simulated device through which guest panic event is sent to host. This driver provides support for the pvpanic device. pvpanic is a paravirtualized device provided by QEMU; it lets a virtual machine (guest) communicate panic events to the host. > endif # X86_PLATFORM_DEVICES > diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile > index ace2b38..ef0ec74 100644 > --- a/drivers/platform/x86/Makefile > +++ b/drivers/platform/x86/Makefile > @@ -51,3 +51,5 @@ obj-$(CONFIG_INTEL_OAKTRAIL) += intel_oaktrail.o > obj-$(CONFIG_SAMSUNG_Q10) += samsung-q10.o > obj-$(CONFIG_APPLE_GMUX) += apple-gmux.o > obj-$(CONFIG_CHROMEOS_LAPTOP) += chromeos_laptop.o > + > +obj-$(CONFIG_PVPANIC) += pvpanic.o > diff --git a/drivers/platform/x86/pvpanic.c b/drivers/platform/x86/pvpanic.c > new file mode 100644 > index 0000000..81c95ec > --- /dev/null > +++ b/drivers/platform/x86/pvpanic.c > @@ -0,0 +1,115 @@ > +/* > + * pvpanic.c - pvpanic Device Support > + * > + * Copyright (C) 2013 Fujitsu. > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License as published by > + * the Free Software Foundation; either version 2 of the License, or > + * (at your option) any later version. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + * > + * You should have received a copy of the GNU General Public License > + * along with this program; if not, write to the Free Software > + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA > + */ > + > +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt > + > +#include <linux/kernel.h> > +#include <linux/module.h> > +#include <linux/init.h> > +#include <linux/types.h> > +#include <acpi/acpi_bus.h> > +#include <acpi/acpi_drivers.h> > + > +MODULE_AUTHOR("Hu Tao <hutao@cn.fujitsu.com>"); > +MODULE_DESCRIPTION("pvpanic device driver"); > +MODULE_LICENSE("GPL"); > + > +static int pvpanic_add(struct acpi_device *device); > +static int pvpanic_remove(struct acpi_device *device); > + > +static const struct acpi_device_id pvpanic_device_ids[] = { > + { "QEMU0001", 0}, > + { "", 0}, > +}; > +MODULE_DEVICE_TABLE(acpi, pvpanic_device_ids); > + > +#define PVPANIC_PANICKED (1 << 0) > + > +static acpi_handle handle; > + > +static struct acpi_driver pvpanic_driver = { > + .name = "pvpanic", > + .class = "QEMU", > + .ids = pvpanic_device_ids, > + .ops = { > + .add = pvpanic_add, > + .remove = pvpanic_remove, > + }, > + .owner = THIS_MODULE, > +}; > + > +static void > +pvpanic_send_event(unsigned int event) > +{ > + union acpi_object arg; > + struct acpi_object_list arg_list; > + > + if (!handle) > + return; > + > + arg.type = ACPI_TYPE_INTEGER; > + arg.integer.value = event; > + > + arg_list.count = 1; > + arg_list.pointer = &arg; > + > + acpi_evaluate_object(handle, "WRPT", &arg_list, NULL); > +} > + > +static int > +pvpanic_panic_notify(struct notifier_block *nb, unsigned long code, > + void *unused) > +{ > + pvpanic_send_event(PVPANIC_PANICKED); > + return NOTIFY_DONE; > +} > + > +static struct notifier_block pvpanic_panic_nb = { > + .notifier_call = pvpanic_panic_notify, > +}; > + > +static int pvpanic_add(struct acpi_device *device) > +{ > + acpi_status status; > + u64 ret; > + > + status = acpi_evaluate_integer(device->handle, "_STA", NULL, > + &ret); > + > + if (ACPI_FAILURE(status) || (ret & 0x0B) != 0x0B) > + return -ENODEV; > + > + handle = device->handle; > + atomic_notifier_chain_register(&panic_notifier_list, > + &pvpanic_panic_nb); > + > + return 0; > +} > + > +static int pvpanic_remove(struct acpi_device *device) > +{ > + > + atomic_notifier_chain_unregister(&panic_notifier_list, > + &pvpanic_panic_nb); > + handle = NULL; > + return 0; > +} > + > +module_acpi_driver(pvpanic_driver); > -- 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
On Fri, May 03, 2013 at 10:47:10AM +0800, Hu Tao wrote: > pvpanic device is a qemu simulated device through which guest panic > event is sent to host. > > Signed-off-by: Hu Tao <hutao@cn.fujitsu.com> > --- > drivers/platform/x86/Kconfig | 7 +++ > drivers/platform/x86/Makefile | 2 + > drivers/platform/x86/pvpanic.c | 115 +++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 124 insertions(+) > create mode 100644 drivers/platform/x86/pvpanic.c > > diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig > index 3338437..527ed04 100644 > --- a/drivers/platform/x86/Kconfig > +++ b/drivers/platform/x86/Kconfig > @@ -781,4 +781,11 @@ config APPLE_GMUX > graphics as well as the backlight. Currently only backlight > control is supported by the driver. > > +config PVPANIC > + tristate "pvpanic device support" > + depends on ACPI > + ---help--- > + This driver provides support for pvpanic device, which is a qemu > + simulated device through which guest panic event is sent to host. > + > endif # X86_PLATFORM_DEVICES > diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile > index ace2b38..ef0ec74 100644 > --- a/drivers/platform/x86/Makefile > +++ b/drivers/platform/x86/Makefile > @@ -51,3 +51,5 @@ obj-$(CONFIG_INTEL_OAKTRAIL) += intel_oaktrail.o > obj-$(CONFIG_SAMSUNG_Q10) += samsung-q10.o > obj-$(CONFIG_APPLE_GMUX) += apple-gmux.o > obj-$(CONFIG_CHROMEOS_LAPTOP) += chromeos_laptop.o > + > +obj-$(CONFIG_PVPANIC) += pvpanic.o > diff --git a/drivers/platform/x86/pvpanic.c b/drivers/platform/x86/pvpanic.c > new file mode 100644 > index 0000000..81c95ec > --- /dev/null > +++ b/drivers/platform/x86/pvpanic.c > @@ -0,0 +1,115 @@ > +/* > + * pvpanic.c - pvpanic Device Support > + * > + * Copyright (C) 2013 Fujitsu. > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License as published by > + * the Free Software Foundation; either version 2 of the License, or > + * (at your option) any later version. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + * > + * You should have received a copy of the GNU General Public License > + * along with this program; if not, write to the Free Software > + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA > + */ > + > +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt > + > +#include <linux/kernel.h> > +#include <linux/module.h> > +#include <linux/init.h> > +#include <linux/types.h> > +#include <acpi/acpi_bus.h> > +#include <acpi/acpi_drivers.h> > + > +MODULE_AUTHOR("Hu Tao <hutao@cn.fujitsu.com>"); > +MODULE_DESCRIPTION("pvpanic device driver"); > +MODULE_LICENSE("GPL"); > + > +static int pvpanic_add(struct acpi_device *device); > +static int pvpanic_remove(struct acpi_device *device); > + > +static const struct acpi_device_id pvpanic_device_ids[] = { > + { "QEMU0001", 0}, > + { "", 0}, > +}; > +MODULE_DEVICE_TABLE(acpi, pvpanic_device_ids); > + > +#define PVPANIC_PANICKED (1 << 0) > + > +static acpi_handle handle; > + > +static struct acpi_driver pvpanic_driver = { > + .name = "pvpanic", > + .class = "QEMU", > + .ids = pvpanic_device_ids, > + .ops = { > + .add = pvpanic_add, > + .remove = pvpanic_remove, > + }, > + .owner = THIS_MODULE, > +}; > + > +static void > +pvpanic_send_event(unsigned int event) > +{ > + union acpi_object arg; > + struct acpi_object_list arg_list; > + > + if (!handle) > + return; > + > + arg.type = ACPI_TYPE_INTEGER; > + arg.integer.value = event; > + > + arg_list.count = 1; > + arg_list.pointer = &arg; > + > + acpi_evaluate_object(handle, "WRPT", &arg_list, NULL); > +} Is it safe to call acpi_evaluate_object from a panic notifier? For example: - Has it been confirmed that no code invoked via acpi_evaluate_object can panic() ? - acpi_ex_enter_interpreter grabs a mutex. Is that path ever used? -- 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
On Fri, May 03, 2013 at 06:59:18PM -0300, Marcelo Tosatti wrote: > On Fri, May 03, 2013 at 10:47:10AM +0800, Hu Tao wrote: > > pvpanic device is a qemu simulated device through which guest panic > > event is sent to host. > > > > Signed-off-by: Hu Tao <hutao@cn.fujitsu.com> > > --- > > drivers/platform/x86/Kconfig | 7 +++ > > drivers/platform/x86/Makefile | 2 + > > drivers/platform/x86/pvpanic.c | 115 +++++++++++++++++++++++++++++++++++++++++ > > 3 files changed, 124 insertions(+) > > create mode 100644 drivers/platform/x86/pvpanic.c > > > > diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig > > index 3338437..527ed04 100644 > > --- a/drivers/platform/x86/Kconfig > > +++ b/drivers/platform/x86/Kconfig > > @@ -781,4 +781,11 @@ config APPLE_GMUX > > graphics as well as the backlight. Currently only backlight > > control is supported by the driver. > > > > +config PVPANIC > > + tristate "pvpanic device support" > > + depends on ACPI > > + ---help--- > > + This driver provides support for pvpanic device, which is a qemu > > + simulated device through which guest panic event is sent to host. > > + > > endif # X86_PLATFORM_DEVICES > > diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile > > index ace2b38..ef0ec74 100644 > > --- a/drivers/platform/x86/Makefile > > +++ b/drivers/platform/x86/Makefile > > @@ -51,3 +51,5 @@ obj-$(CONFIG_INTEL_OAKTRAIL) += intel_oaktrail.o > > obj-$(CONFIG_SAMSUNG_Q10) += samsung-q10.o > > obj-$(CONFIG_APPLE_GMUX) += apple-gmux.o > > obj-$(CONFIG_CHROMEOS_LAPTOP) += chromeos_laptop.o > > + > > +obj-$(CONFIG_PVPANIC) += pvpanic.o > > diff --git a/drivers/platform/x86/pvpanic.c b/drivers/platform/x86/pvpanic.c > > new file mode 100644 > > index 0000000..81c95ec > > --- /dev/null > > +++ b/drivers/platform/x86/pvpanic.c > > @@ -0,0 +1,115 @@ > > +/* > > + * pvpanic.c - pvpanic Device Support > > + * > > + * Copyright (C) 2013 Fujitsu. > > + * > > + * This program is free software; you can redistribute it and/or modify > > + * it under the terms of the GNU General Public License as published by > > + * the Free Software Foundation; either version 2 of the License, or > > + * (at your option) any later version. > > + * > > + * This program is distributed in the hope that it will be useful, > > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > > + * GNU General Public License for more details. > > + * > > + * You should have received a copy of the GNU General Public License > > + * along with this program; if not, write to the Free Software > > + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA > > + */ > > + > > +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt > > + > > +#include <linux/kernel.h> > > +#include <linux/module.h> > > +#include <linux/init.h> > > +#include <linux/types.h> > > +#include <acpi/acpi_bus.h> > > +#include <acpi/acpi_drivers.h> > > + > > +MODULE_AUTHOR("Hu Tao <hutao@cn.fujitsu.com>"); > > +MODULE_DESCRIPTION("pvpanic device driver"); > > +MODULE_LICENSE("GPL"); > > + > > +static int pvpanic_add(struct acpi_device *device); > > +static int pvpanic_remove(struct acpi_device *device); > > + > > +static const struct acpi_device_id pvpanic_device_ids[] = { > > + { "QEMU0001", 0}, > > + { "", 0}, > > +}; > > +MODULE_DEVICE_TABLE(acpi, pvpanic_device_ids); > > + > > +#define PVPANIC_PANICKED (1 << 0) > > + > > +static acpi_handle handle; > > + > > +static struct acpi_driver pvpanic_driver = { > > + .name = "pvpanic", > > + .class = "QEMU", > > + .ids = pvpanic_device_ids, > > + .ops = { > > + .add = pvpanic_add, > > + .remove = pvpanic_remove, > > + }, > > + .owner = THIS_MODULE, > > +}; > > + > > +static void > > +pvpanic_send_event(unsigned int event) > > +{ > > + union acpi_object arg; > > + struct acpi_object_list arg_list; > > + > > + if (!handle) > > + return; > > + > > + arg.type = ACPI_TYPE_INTEGER; > > + arg.integer.value = event; > > + > > + arg_list.count = 1; > > + arg_list.pointer = &arg; > > + > > + acpi_evaluate_object(handle, "WRPT", &arg_list, NULL); > > +} > > Is it safe to call acpi_evaluate_object from a panic notifier? For > example: > > - Has it been confirmed that no code invoked via acpi_evaluate_object can panic() ? Confirmed. > - acpi_ex_enter_interpreter grabs a mutex. Is that path ever used? Unfortunately yes. As I can tell, there are 2 places in the path to grab a mutex: when searching the namespace for the method, and when executing the method. I didn't find a non-blocking version of acpi_evaluate_object. -- 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
On Mon, May 06, 2013 at 11:39:35AM +0800, Hu Tao wrote: > On Fri, May 03, 2013 at 06:59:18PM -0300, Marcelo Tosatti wrote: > > On Fri, May 03, 2013 at 10:47:10AM +0800, Hu Tao wrote: > > > pvpanic device is a qemu simulated device through which guest panic > > > event is sent to host. > > > > > > Signed-off-by: Hu Tao <hutao@cn.fujitsu.com> > > > --- > > > drivers/platform/x86/Kconfig | 7 +++ > > > drivers/platform/x86/Makefile | 2 + > > > drivers/platform/x86/pvpanic.c | 115 +++++++++++++++++++++++++++++++++++++++++ > > > 3 files changed, 124 insertions(+) > > > create mode 100644 drivers/platform/x86/pvpanic.c > > > > > > diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig > > > index 3338437..527ed04 100644 > > > --- a/drivers/platform/x86/Kconfig > > > +++ b/drivers/platform/x86/Kconfig > > > @@ -781,4 +781,11 @@ config APPLE_GMUX > > > graphics as well as the backlight. Currently only backlight > > > control is supported by the driver. > > > > > > +config PVPANIC > > > + tristate "pvpanic device support" > > > + depends on ACPI > > > + ---help--- > > > + This driver provides support for pvpanic device, which is a qemu > > > + simulated device through which guest panic event is sent to host. > > > + > > > endif # X86_PLATFORM_DEVICES > > > diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile > > > index ace2b38..ef0ec74 100644 > > > --- a/drivers/platform/x86/Makefile > > > +++ b/drivers/platform/x86/Makefile > > > @@ -51,3 +51,5 @@ obj-$(CONFIG_INTEL_OAKTRAIL) += intel_oaktrail.o > > > obj-$(CONFIG_SAMSUNG_Q10) += samsung-q10.o > > > obj-$(CONFIG_APPLE_GMUX) += apple-gmux.o > > > obj-$(CONFIG_CHROMEOS_LAPTOP) += chromeos_laptop.o > > > + > > > +obj-$(CONFIG_PVPANIC) += pvpanic.o > > > diff --git a/drivers/platform/x86/pvpanic.c b/drivers/platform/x86/pvpanic.c > > > new file mode 100644 > > > index 0000000..81c95ec > > > --- /dev/null > > > +++ b/drivers/platform/x86/pvpanic.c > > > @@ -0,0 +1,115 @@ > > > +/* > > > + * pvpanic.c - pvpanic Device Support > > > + * > > > + * Copyright (C) 2013 Fujitsu. > > > + * > > > + * This program is free software; you can redistribute it and/or modify > > > + * it under the terms of the GNU General Public License as published by > > > + * the Free Software Foundation; either version 2 of the License, or > > > + * (at your option) any later version. > > > + * > > > + * This program is distributed in the hope that it will be useful, > > > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > > > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > > > + * GNU General Public License for more details. > > > + * > > > + * You should have received a copy of the GNU General Public License > > > + * along with this program; if not, write to the Free Software > > > + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA > > > + */ > > > + > > > +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt > > > + > > > +#include <linux/kernel.h> > > > +#include <linux/module.h> > > > +#include <linux/init.h> > > > +#include <linux/types.h> > > > +#include <acpi/acpi_bus.h> > > > +#include <acpi/acpi_drivers.h> > > > + > > > +MODULE_AUTHOR("Hu Tao <hutao@cn.fujitsu.com>"); > > > +MODULE_DESCRIPTION("pvpanic device driver"); > > > +MODULE_LICENSE("GPL"); > > > + > > > +static int pvpanic_add(struct acpi_device *device); > > > +static int pvpanic_remove(struct acpi_device *device); > > > + > > > +static const struct acpi_device_id pvpanic_device_ids[] = { > > > + { "QEMU0001", 0}, > > > + { "", 0}, > > > +}; > > > +MODULE_DEVICE_TABLE(acpi, pvpanic_device_ids); > > > + > > > +#define PVPANIC_PANICKED (1 << 0) > > > + > > > +static acpi_handle handle; > > > + > > > +static struct acpi_driver pvpanic_driver = { > > > + .name = "pvpanic", > > > + .class = "QEMU", > > > + .ids = pvpanic_device_ids, > > > + .ops = { > > > + .add = pvpanic_add, > > > + .remove = pvpanic_remove, > > > + }, > > > + .owner = THIS_MODULE, > > > +}; > > > + > > > +static void > > > +pvpanic_send_event(unsigned int event) > > > +{ > > > + union acpi_object arg; > > > + struct acpi_object_list arg_list; > > > + > > > + if (!handle) > > > + return; > > > + > > > + arg.type = ACPI_TYPE_INTEGER; > > > + arg.integer.value = event; > > > + > > > + arg_list.count = 1; > > > + arg_list.pointer = &arg; > > > + > > > + acpi_evaluate_object(handle, "WRPT", &arg_list, NULL); > > > +} > > > > Is it safe to call acpi_evaluate_object from a panic notifier? For > > example: > > > > - Has it been confirmed that no code invoked via acpi_evaluate_object can panic() ? > > Confirmed. > > > - acpi_ex_enter_interpreter grabs a mutex. Is that path ever used? > > Unfortunately yes. As I can tell, there are 2 places in the path to grab > a mutex: when searching the namespace for the method, and when executing > the method. I didn't find a non-blocking version of acpi_evaluate_object. Then thats a bug because the pvpanic notifier is called with interrupts disabled. Suppose its safer to use an OUT instruction? -- 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
Il 06/05/2013 13:38, Marcelo Tosatti ha scritto: > On Mon, May 06, 2013 at 11:39:35AM +0800, Hu Tao wrote: >> On Fri, May 03, 2013 at 06:59:18PM -0300, Marcelo Tosatti wrote: >>> On Fri, May 03, 2013 at 10:47:10AM +0800, Hu Tao wrote: >>>> pvpanic device is a qemu simulated device through which guest panic >>>> event is sent to host. >>>> >>>> Signed-off-by: Hu Tao <hutao@cn.fujitsu.com> >>>> --- >>>> drivers/platform/x86/Kconfig | 7 +++ >>>> drivers/platform/x86/Makefile | 2 + >>>> drivers/platform/x86/pvpanic.c | 115 +++++++++++++++++++++++++++++++++++++++++ >>>> 3 files changed, 124 insertions(+) >>>> create mode 100644 drivers/platform/x86/pvpanic.c >>>> >>>> diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig >>>> index 3338437..527ed04 100644 >>>> --- a/drivers/platform/x86/Kconfig >>>> +++ b/drivers/platform/x86/Kconfig >>>> @@ -781,4 +781,11 @@ config APPLE_GMUX >>>> graphics as well as the backlight. Currently only backlight >>>> control is supported by the driver. >>>> >>>> +config PVPANIC >>>> + tristate "pvpanic device support" >>>> + depends on ACPI >>>> + ---help--- >>>> + This driver provides support for pvpanic device, which is a qemu >>>> + simulated device through which guest panic event is sent to host. >>>> + >>>> endif # X86_PLATFORM_DEVICES >>>> diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile >>>> index ace2b38..ef0ec74 100644 >>>> --- a/drivers/platform/x86/Makefile >>>> +++ b/drivers/platform/x86/Makefile >>>> @@ -51,3 +51,5 @@ obj-$(CONFIG_INTEL_OAKTRAIL) += intel_oaktrail.o >>>> obj-$(CONFIG_SAMSUNG_Q10) += samsung-q10.o >>>> obj-$(CONFIG_APPLE_GMUX) += apple-gmux.o >>>> obj-$(CONFIG_CHROMEOS_LAPTOP) += chromeos_laptop.o >>>> + >>>> +obj-$(CONFIG_PVPANIC) += pvpanic.o >>>> diff --git a/drivers/platform/x86/pvpanic.c b/drivers/platform/x86/pvpanic.c >>>> new file mode 100644 >>>> index 0000000..81c95ec >>>> --- /dev/null >>>> +++ b/drivers/platform/x86/pvpanic.c >>>> @@ -0,0 +1,115 @@ >>>> +/* >>>> + * pvpanic.c - pvpanic Device Support >>>> + * >>>> + * Copyright (C) 2013 Fujitsu. >>>> + * >>>> + * This program is free software; you can redistribute it and/or modify >>>> + * it under the terms of the GNU General Public License as published by >>>> + * the Free Software Foundation; either version 2 of the License, or >>>> + * (at your option) any later version. >>>> + * >>>> + * This program is distributed in the hope that it will be useful, >>>> + * but WITHOUT ANY WARRANTY; without even the implied warranty of >>>> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the >>>> + * GNU General Public License for more details. >>>> + * >>>> + * You should have received a copy of the GNU General Public License >>>> + * along with this program; if not, write to the Free Software >>>> + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA >>>> + */ >>>> + >>>> +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt >>>> + >>>> +#include <linux/kernel.h> >>>> +#include <linux/module.h> >>>> +#include <linux/init.h> >>>> +#include <linux/types.h> >>>> +#include <acpi/acpi_bus.h> >>>> +#include <acpi/acpi_drivers.h> >>>> + >>>> +MODULE_AUTHOR("Hu Tao <hutao@cn.fujitsu.com>"); >>>> +MODULE_DESCRIPTION("pvpanic device driver"); >>>> +MODULE_LICENSE("GPL"); >>>> + >>>> +static int pvpanic_add(struct acpi_device *device); >>>> +static int pvpanic_remove(struct acpi_device *device); >>>> + >>>> +static const struct acpi_device_id pvpanic_device_ids[] = { >>>> + { "QEMU0001", 0}, >>>> + { "", 0}, >>>> +}; >>>> +MODULE_DEVICE_TABLE(acpi, pvpanic_device_ids); >>>> + >>>> +#define PVPANIC_PANICKED (1 << 0) >>>> + >>>> +static acpi_handle handle; >>>> + >>>> +static struct acpi_driver pvpanic_driver = { >>>> + .name = "pvpanic", >>>> + .class = "QEMU", >>>> + .ids = pvpanic_device_ids, >>>> + .ops = { >>>> + .add = pvpanic_add, >>>> + .remove = pvpanic_remove, >>>> + }, >>>> + .owner = THIS_MODULE, >>>> +}; >>>> + >>>> +static void >>>> +pvpanic_send_event(unsigned int event) >>>> +{ >>>> + union acpi_object arg; >>>> + struct acpi_object_list arg_list; >>>> + >>>> + if (!handle) >>>> + return; >>>> + >>>> + arg.type = ACPI_TYPE_INTEGER; >>>> + arg.integer.value = event; >>>> + >>>> + arg_list.count = 1; >>>> + arg_list.pointer = &arg; >>>> + >>>> + acpi_evaluate_object(handle, "WRPT", &arg_list, NULL); >>>> +} >>> >>> Is it safe to call acpi_evaluate_object from a panic notifier? For >>> example: >>> >>> - Has it been confirmed that no code invoked via acpi_evaluate_object can panic() ? >> >> Confirmed. >> >>> - acpi_ex_enter_interpreter grabs a mutex. Is that path ever used? >> >> Unfortunately yes. As I can tell, there are 2 places in the path to grab >> a mutex: when searching the namespace for the method, and when executing >> the method. I didn't find a non-blocking version of acpi_evaluate_object. > > Then thats a bug because the pvpanic notifier is called with interrupts > disabled. > > Suppose its safer to use an OUT instruction? Yeah, it probably is... You can still use acpi_walk_resources to find the port number instead of hard-coding 0x505... Paolo -- 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
diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig index 3338437..527ed04 100644 --- a/drivers/platform/x86/Kconfig +++ b/drivers/platform/x86/Kconfig @@ -781,4 +781,11 @@ config APPLE_GMUX graphics as well as the backlight. Currently only backlight control is supported by the driver. +config PVPANIC + tristate "pvpanic device support" + depends on ACPI + ---help--- + This driver provides support for pvpanic device, which is a qemu + simulated device through which guest panic event is sent to host. + endif # X86_PLATFORM_DEVICES diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile index ace2b38..ef0ec74 100644 --- a/drivers/platform/x86/Makefile +++ b/drivers/platform/x86/Makefile @@ -51,3 +51,5 @@ obj-$(CONFIG_INTEL_OAKTRAIL) += intel_oaktrail.o obj-$(CONFIG_SAMSUNG_Q10) += samsung-q10.o obj-$(CONFIG_APPLE_GMUX) += apple-gmux.o obj-$(CONFIG_CHROMEOS_LAPTOP) += chromeos_laptop.o + +obj-$(CONFIG_PVPANIC) += pvpanic.o diff --git a/drivers/platform/x86/pvpanic.c b/drivers/platform/x86/pvpanic.c new file mode 100644 index 0000000..81c95ec --- /dev/null +++ b/drivers/platform/x86/pvpanic.c @@ -0,0 +1,115 @@ +/* + * pvpanic.c - pvpanic Device Support + * + * Copyright (C) 2013 Fujitsu. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/types.h> +#include <acpi/acpi_bus.h> +#include <acpi/acpi_drivers.h> + +MODULE_AUTHOR("Hu Tao <hutao@cn.fujitsu.com>"); +MODULE_DESCRIPTION("pvpanic device driver"); +MODULE_LICENSE("GPL"); + +static int pvpanic_add(struct acpi_device *device); +static int pvpanic_remove(struct acpi_device *device); + +static const struct acpi_device_id pvpanic_device_ids[] = { + { "QEMU0001", 0}, + { "", 0}, +}; +MODULE_DEVICE_TABLE(acpi, pvpanic_device_ids); + +#define PVPANIC_PANICKED (1 << 0) + +static acpi_handle handle; + +static struct acpi_driver pvpanic_driver = { + .name = "pvpanic", + .class = "QEMU", + .ids = pvpanic_device_ids, + .ops = { + .add = pvpanic_add, + .remove = pvpanic_remove, + }, + .owner = THIS_MODULE, +}; + +static void +pvpanic_send_event(unsigned int event) +{ + union acpi_object arg; + struct acpi_object_list arg_list; + + if (!handle) + return; + + arg.type = ACPI_TYPE_INTEGER; + arg.integer.value = event; + + arg_list.count = 1; + arg_list.pointer = &arg; + + acpi_evaluate_object(handle, "WRPT", &arg_list, NULL); +} + +static int +pvpanic_panic_notify(struct notifier_block *nb, unsigned long code, + void *unused) +{ + pvpanic_send_event(PVPANIC_PANICKED); + return NOTIFY_DONE; +} + +static struct notifier_block pvpanic_panic_nb = { + .notifier_call = pvpanic_panic_notify, +}; + +static int pvpanic_add(struct acpi_device *device) +{ + acpi_status status; + u64 ret; + + status = acpi_evaluate_integer(device->handle, "_STA", NULL, + &ret); + + if (ACPI_FAILURE(status) || (ret & 0x0B) != 0x0B) + return -ENODEV; + + handle = device->handle; + atomic_notifier_chain_register(&panic_notifier_list, + &pvpanic_panic_nb); + + return 0; +} + +static int pvpanic_remove(struct acpi_device *device) +{ + + atomic_notifier_chain_unregister(&panic_notifier_list, + &pvpanic_panic_nb); + handle = NULL; + return 0; +} + +module_acpi_driver(pvpanic_driver);
pvpanic device is a qemu simulated device through which guest panic event is sent to host. Signed-off-by: Hu Tao <hutao@cn.fujitsu.com> --- drivers/platform/x86/Kconfig | 7 +++ drivers/platform/x86/Makefile | 2 + drivers/platform/x86/pvpanic.c | 115 +++++++++++++++++++++++++++++++++++++++++ 3 files changed, 124 insertions(+) create mode 100644 drivers/platform/x86/pvpanic.c