| Message ID | 1435226570-3669-49-git-send-email-luis.henriques@canonical.com |
|---|---|
| State | New |
| Headers | show |
On Thu, Jun 25, 2015 at 11:02:27AM +0100, Luis Henriques wrote: > 3.16.7-ckt14 -stable review patch. If anyone has any objections, please let me know. > As pointed out by Greg, this is actually a new feature that shouldn't be added to -stable releases. Thus, I'm dropping this patch and 5ef5b6927f14 ("Drivers: hv: vmbus: Correcting truncation error for constant HV_CRASH_CTL_CRASH_NOTIFY") Cheers, -- Luís > ------------------ > > From: Nick Meier <nmeier@microsoft.com> > > commit 96c1d0581d00f7abe033350edb021a9d947d8d81 upstream. > > Hyper-V allows a guest to notify the Hyper-V host that a panic > condition occured. This notification can include up to five 64 > bit values. These 64 bit values are written into crash MSRs. > Once the data has been written into the crash MSRs, the host is > then notified by writing into a Crash Control MSR. On the Hyper-V > host, the panic notification data is captured in the Windows Event > log as a 18590 event. > > Crash MSRs are defined in appendix H of the Hypervisor Top Level > Functional Specification. At the time of this patch, v4.0 is the > current functional spec. The URL for the v4.0 document is: > > http://download.microsoft.com/download/A/B/4/AB43A34E-BDD0-4FA6-BDEF-79EEF16E880B/Hypervisor Top Level Functional Specification v4.0.docx > > Signed-off-by: Nick Meier <nmeier@microsoft.com> > Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> > Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> > Signed-off-by: Joseph Salisbury <joseph.salisbury@canonical.com> > Signed-off-by: Luis Henriques <luis.henriques@canonical.com> > --- > drivers/hv/hyperv_vmbus.h | 11 +++++++++++ > drivers/hv/vmbus_drv.c | 35 +++++++++++++++++++++++++++++++++++ > 2 files changed, 46 insertions(+) > > diff --git a/drivers/hv/hyperv_vmbus.h b/drivers/hv/hyperv_vmbus.h > index c386d8dc7223..64318c03002a 100644 > --- a/drivers/hv/hyperv_vmbus.h > +++ b/drivers/hv/hyperv_vmbus.h > @@ -49,6 +49,17 @@ enum hv_cpuid_function { > HVCPUID_IMPLEMENTATION_LIMITS = 0x40000005, > }; > > +#define HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE 0x400 > + > +#define HV_X64_MSR_CRASH_P0 0x40000100 > +#define HV_X64_MSR_CRASH_P1 0x40000101 > +#define HV_X64_MSR_CRASH_P2 0x40000102 > +#define HV_X64_MSR_CRASH_P3 0x40000103 > +#define HV_X64_MSR_CRASH_P4 0x40000104 > +#define HV_X64_MSR_CRASH_CTL 0x40000105 > + > +#define HV_CRASH_CTL_CRASH_NOTIFY 0x8000000000000000 > + > /* Define version of the synthetic interrupt controller. */ > #define HV_SYNIC_VERSION (1) > > diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c > index 4d6b26979fbd..3d2d710744ca 100644 > --- a/drivers/hv/vmbus_drv.c > +++ b/drivers/hv/vmbus_drv.c > @@ -35,6 +35,8 @@ > #include <asm/hyperv.h> > #include <asm/hypervisor.h> > #include <asm/mshyperv.h> > +#include <linux/notifier.h> > +#include <linux/ptrace.h> > #include "hyperv_vmbus.h" > > static struct acpi_device *hv_acpi_dev; > @@ -43,6 +45,31 @@ static struct tasklet_struct msg_dpc; > static struct completion probe_event; > static int irq; > > + > +int hyperv_panic_event(struct notifier_block *nb, > + unsigned long event, void *ptr) > +{ > + struct pt_regs *regs; > + > + regs = current_pt_regs(); > + > + wrmsrl(HV_X64_MSR_CRASH_P0, regs->ip); > + wrmsrl(HV_X64_MSR_CRASH_P1, regs->ax); > + wrmsrl(HV_X64_MSR_CRASH_P2, regs->bx); > + wrmsrl(HV_X64_MSR_CRASH_P3, regs->cx); > + wrmsrl(HV_X64_MSR_CRASH_P4, regs->dx); > + > + /* > + * Let Hyper-V know there is crash data available > + */ > + wrmsrl(HV_X64_MSR_CRASH_CTL, HV_CRASH_CTL_CRASH_NOTIFY); > + return NOTIFY_DONE; > +} > + > +static struct notifier_block hyperv_panic_block = { > + .notifier_call = hyperv_panic_event, > +}; > + > struct resource hyperv_mmio = { > .name = "hyperv mmio", > .flags = IORESOURCE_MEM, > @@ -711,6 +738,14 @@ static int vmbus_bus_init(int irq) > if (ret) > goto err_alloc; > > + /* > + * Only register if the crash MSRs are available > + */ > + if (ms_hyperv.features & HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE) { > + atomic_notifier_chain_register(&panic_notifier_list, > + &hyperv_panic_block); > + } > + > vmbus_request_offers(); > > return 0;
diff --git a/drivers/hv/hyperv_vmbus.h b/drivers/hv/hyperv_vmbus.h index c386d8dc7223..64318c03002a 100644 --- a/drivers/hv/hyperv_vmbus.h +++ b/drivers/hv/hyperv_vmbus.h @@ -49,6 +49,17 @@ enum hv_cpuid_function { HVCPUID_IMPLEMENTATION_LIMITS = 0x40000005, }; +#define HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE 0x400 + +#define HV_X64_MSR_CRASH_P0 0x40000100 +#define HV_X64_MSR_CRASH_P1 0x40000101 +#define HV_X64_MSR_CRASH_P2 0x40000102 +#define HV_X64_MSR_CRASH_P3 0x40000103 +#define HV_X64_MSR_CRASH_P4 0x40000104 +#define HV_X64_MSR_CRASH_CTL 0x40000105 + +#define HV_CRASH_CTL_CRASH_NOTIFY 0x8000000000000000 + /* Define version of the synthetic interrupt controller. */ #define HV_SYNIC_VERSION (1) diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c index 4d6b26979fbd..3d2d710744ca 100644 --- a/drivers/hv/vmbus_drv.c +++ b/drivers/hv/vmbus_drv.c @@ -35,6 +35,8 @@ #include <asm/hyperv.h> #include <asm/hypervisor.h> #include <asm/mshyperv.h> +#include <linux/notifier.h> +#include <linux/ptrace.h> #include "hyperv_vmbus.h" static struct acpi_device *hv_acpi_dev; @@ -43,6 +45,31 @@ static struct tasklet_struct msg_dpc; static struct completion probe_event; static int irq; + +int hyperv_panic_event(struct notifier_block *nb, + unsigned long event, void *ptr) +{ + struct pt_regs *regs; + + regs = current_pt_regs(); + + wrmsrl(HV_X64_MSR_CRASH_P0, regs->ip); + wrmsrl(HV_X64_MSR_CRASH_P1, regs->ax); + wrmsrl(HV_X64_MSR_CRASH_P2, regs->bx); + wrmsrl(HV_X64_MSR_CRASH_P3, regs->cx); + wrmsrl(HV_X64_MSR_CRASH_P4, regs->dx); + + /* + * Let Hyper-V know there is crash data available + */ + wrmsrl(HV_X64_MSR_CRASH_CTL, HV_CRASH_CTL_CRASH_NOTIFY); + return NOTIFY_DONE; +} + +static struct notifier_block hyperv_panic_block = { + .notifier_call = hyperv_panic_event, +}; + struct resource hyperv_mmio = { .name = "hyperv mmio", .flags = IORESOURCE_MEM, @@ -711,6 +738,14 @@ static int vmbus_bus_init(int irq) if (ret) goto err_alloc; + /* + * Only register if the crash MSRs are available + */ + if (ms_hyperv.features & HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE) { + atomic_notifier_chain_register(&panic_notifier_list, + &hyperv_panic_block); + } + vmbus_request_offers(); return 0;