Re: [PATCH 1/1 V5] kernel/kvm: introduce KVM_SET_LINT1 and fix improper nmi emulation

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 10/16/2011 05:39 PM, Avi Kivity wrote:
> On 10/14/2011 11:03 AM, Lai Jiangshan wrote:
>> Currently, NMI interrupt is blindly sent to all the vCPUs when NMI
>> button event happens. This doesn't properly emulate real hardware on
>> which NMI button event triggers LINT1. Because of this, NMI is sent to
>> the processor even when LINT1 is masked in LVT. For example, this
>> causes the problem that kdump initiated by NMI sometimes doesn't work
>> on KVM, because kdump assumes NMI is masked on CPUs other than CPU0.
>>
>> With this patch, we introduce introduce KVM_SET_LINT1,
>> and we can use KVM_SET_LINT1 to correctly emulate NMI button
>> without change the old KVM_NMI behavior.
>>  
>> @@ -759,6 +762,8 @@ struct kvm_clock_data {
>>  #define KVM_CREATE_SPAPR_TCE	  _IOW(KVMIO,  0xa8, struct kvm_create_spapr_tce)
>>  /* Available with KVM_CAP_RMA */
>>  #define KVM_ALLOCATE_RMA	  _IOR(KVMIO,  0xa9, struct kvm_allocate_rma)
>> +/* Available with KVM_CAP_SET_LINT1 for x86 */
>> +#define KVM_SET_LINT1		  _IO(KVMIO,   0xaa)
>>  
>>
> 
> LINT1 may have been programmed as a level -triggered interrupt instead
> of edge triggered (NMI or interrupt).  We can use the ioctl argument for
> the level (and pressing the NMI button needs to pulse the level to 1 and
> back to 0).
> 

Hi, Avi,

How to handle level=0 in the kernel?
Or just ignore it?

Thanks,
Lai
--
To unsubscribe from this list: send the line "unsubscribe kvm" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html


[Index of Archives]     [KVM ARM]     [KVM ia64]     [KVM ppc]     [Virtualization Tools]     [Spice Development]     [Libvirt]     [Libvirt Users]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite Questions]     [Linux Kernel]     [Linux SCSI]     [XFree86]
  Powered by Linux