Messages in this thread | | | Date | Fri, 25 Sep 2015 11:54:05 -0400 | From | Boris Ostrovsky <> | Subject | Re: [PATCH] xen/pvhvm: add soft reset on kexec/kdump support |
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On 09/25/2015 09:59 AM, Konrad Rzeszutek Wilk wrote: > On Fri, Sep 25, 2015 at 11:59:52AM +0200, Vitaly Kuznetsov wrote: >> Currently there is a number of issues preventing PVHVM Xen guests from >> doing successful kexec/kdump: >> - Bound event channels. >> - Registered vcpu_info. >> - PIRQ/emuirq mappings. >> - shared_info frame after XENMAPSPACE_shared_info operation. >> - Active grant mappings. >> Basically, newly booted kernel stumbles upon already set up Xen interfaces >> and there is no way to reestablish them. In Xen-4.7 a new feature called >> 'soft reset' is coming. A guest performing kexec/kdump operation is >> supposed to call SCHEDOP_shutdown hypercall with SHUTDOWN_soft_reset reason >> before jumping to new kernel. Hypervisor (with some help from toolstack) >> will do full domain cleanup (but keeping its memory and vCPU contexts >> intact) returning the guest to the state it had when it was first booted >> and thus allowing it to start over. >> >> Doing SHUTDOWN_soft_reset on Xen hypervisors which don't support it is >> probably OK as by default all unknown shutdown reasons cause domain destroy >> with a message in toolstack log: >> 'Unknown shutdown reason code 5. Destroying domain.' >> which gives a clue to what the problem is and eliminates false >> expectations. >> >> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> > Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> > > with s/pvhvm/hvm/ > > to match with the rest of the file. > > Thanks. >> >> +#ifdef CONFIG_KEXEC_CORE >> +static void xen_pvhvm_kexec_shutdown(void) >> +{ >> + native_machine_shutdown(); >> + if (kexec_in_progress) >> + xen_reboot(SHUTDOWN_soft_reset); >> +}
This routine is not kexec-specific so "kexec_" should be dropped from the name.
Also, I am not sure I see how this new op will be used in the hypervisor --- currently AFAICS it is only processed under is_hardware_domain(). Are there other patches that will support HVM guests?
-boris
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