Re: [Crash-utility] [PATCH] Account for the changed type of the domain.vcpu field in Xen4

On Friday 07 of January 2011 16:27:55 Dave Anderson wrote: > ----- Original Message ----- > > > The 'vcpu' field changed from a fixed array to a pointer to an array. > > Change xen_hyper_store_domain_context to account for this change. > > Presuming this tests OK on older hypervisor dumps, this looks OK. > Queued for the next release based upon testing. Hi Dave, older Xen hypervisors didn't have the "max_vcpus" field in struct domain, so there is in fact no change for them. However, thinking about it some more, this might be affected by the increase of XEN_HYPER_MAX_VIRT_CPUS. Although I haven't seen a failure, let me check first whether a crash session on a dump from Xen 3.3 attempts to read past array boundaries.

Petr Tesarik SUSE Linux > Thanks, > Dave > > > Signed-off-by: Petr Tesarik <ptesarik(a)suse.cz&gt; > > --- > > xen_hyper.c | 40 +++++++++++++++++++++++++++++++++++++--- > > xen_hyper_defs.h | 1 + > > 2 files changed, 38 insertions(+), 3 deletions(-) > > > > --- a/xen_hyper.c > > +++ b/xen_hyper.c > > @@ -219,6 +219,7 @@ xen_hyper_domain_init(void) > > > > XEN_HYPER_MEMBER_OFFSET_INIT(domain_is_shutting_down, "domain", > > "is_shutting_down"); > > XEN_HYPER_MEMBER_OFFSET_INIT(domain_is_shut_down, "domain", > > "is_shut_down"); > > XEN_HYPER_MEMBER_OFFSET_INIT(domain_vcpu, "domain", "vcpu"); > > + XEN_HYPER_MEMBER_OFFSET_INIT(domain_max_vcpus, "domain", > > "max_vcpus"); > > XEN_HYPER_MEMBER_OFFSET_INIT(domain_arch, "domain", "arch"); > > > > XEN_HYPER_STRUCT_SIZE_INIT(arch_shared_info, "arch_shared_info"); > > @@ -1207,6 +1208,8 @@ struct xen_hyper_domain_context * > > xen_hyper_store_domain_context(struct xen_hyper_domain_context > > *dc, > > ulong domain, char *dp) > > { > > + unsigned int max_vcpus; > > + char *vcpup; > > int i; > > > > dc->domain = domain; > > @@ -1244,9 +1247,40 @@ xen_hyper_store_domain_context(struct xe > > dc->domain_flags = XEN_HYPER_DOMF_ERROR; > > } > > dc->evtchn = ULONG(dp + XEN_HYPER_OFFSET(domain_evtchn)); > > - for (i = 0; i < XEN_HYPER_MAX_VIRT_CPUS; i++) { > > - dc->vcpu[i] = ULONG(dp + XEN_HYPER_OFFSET(domain_vcpu) + > > i*sizeof(void *)); > > - if (dc->vcpu[i]) XEN_HYPER_NR_VCPUS_IN_DOM(dc)++; > > + > > + if (XEN_HYPER_VALID_MEMBER(domain_max_vcpus)) { > > + max_vcpus = UINT(dp + XEN_HYPER_OFFSET(domain_max_vcpus)); > > + } else { > > + max_vcpus = XEN_HYPER_MAX_VIRT_CPUS; > > + } > > + if (MEMBER_TYPE("domain", "vcpu") == TYPE_CODE_ARRAY) > > + vcpup = dp + XEN_HYPER_OFFSET(domain_vcpu); > > + else { > > + ulong vcpu_array = ULONG(dp + XEN_HYPER_OFFSET(domain_vcpu)); > > + if (vcpu_array && max_vcpus) { > > + if (!(vcpup = > > + malloc(max_vcpus * sizeof(void *)))) { > > + error(FATAL, "cannot malloc VCPU array for domain %lx.", > > + domain); > > + } > > + if (!readmem(vcpu_array, KVADDR, > > + vcpup, max_vcpus * sizeof(void*), > > + "VCPU array", RETURN_ON_ERROR)) { > > + error(FATAL, "cannot read VCPU array for domain %lx.", > > + domain); > > + } > > + } else { > > + vcpup = NULL; > > + } > > + } > > + if (vcpup) { > > + for (i = 0; i < max_vcpus; i++) { > > + dc->vcpu[i] = ULONG(vcpup + i*sizeof(void *)); > > + if (dc->vcpu[i]) XEN_HYPER_NR_VCPUS_IN_DOM(dc)++; > > + } > > + if (vcpup != dp + XEN_HYPER_OFFSET(domain_vcpu)) { > > + free(vcpup); > > + } > > } > > > > return dc; > > --- a/xen_hyper_defs.h > > +++ b/xen_hyper_defs.h > > @@ -674,6 +674,7 @@ struct xen_hyper_offset_table { > > long domain_is_shutting_down; > > long domain_is_shut_down; > > long domain_vcpu; > > + long domain_max_vcpus; > > long domain_arch; > > #ifdef IA64 > > /* mm_struct */ > > > > -- > > Crash-utility mailing list > > Crash-utility(a)redhat.com > > https://www.redhat.com/mailman/listinfo/crash-utility > > -- > Crash-utility mailing list > Crash-utility(a)redhat.com > https://www.redhat.com/mailman/listinfo/crash-utility