On Wed, 3 Mar 2021 14:09:15 +0100 David Hildenbrand <david@xxxxxxxxxx> wrote: > legacy_s390_alloc() was required for dealing with the absence of the ESOP > feature -- on old HW (< gen 10) and old z/VM versions (< 6.3). > > As z/VM v6.2 (and even v6.3) is no longer supported since 2017 [1] > and we don't expect to have real users on such old hardware, let's drop > legacy_s390_alloc(). > > Still check+report an error just in case someone still runs on > such old z/VM environments, or someone runs under weird nested KVM > setups (where we can manually disable ESOP via the CPU model). > > No need to check for KVM_CAP_GMAP - that should always be around on > kernels that also have KVM_CAP_DEVICE_CTRL (>= v3.15). > > [1] https://www.ibm.com/support/lifecycle/search?q=z%2FVM > > Suggested-by: Cornelia Huck <cohuck@xxxxxxxxxx> > Suggested-by: Thomas Huth <thuth@xxxxxxxxxx> > Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx> > Cc: Richard Henderson <rth@xxxxxxxxxxx> > Cc: Halil Pasic <pasic@xxxxxxxxxxxxx> > Cc: Cornelia Huck <cohuck@xxxxxxxxxx> > Cc: Christian Borntraeger <borntraeger@xxxxxxxxxx> > Cc: Thomas Huth <thuth@xxxxxxxxxx> > Cc: Igor Mammedov <imammedo@xxxxxxxxxx> > Cc: Peter Xu <peterx@xxxxxxxxxx> > Signed-off-by: David Hildenbrand <david@xxxxxxxxxx> Reviewed-by: Igor Mammedov <imammedo@xxxxxxxxxx> > --- > target/s390x/kvm.c | 43 +++++-------------------------------------- > 1 file changed, 5 insertions(+), 38 deletions(-) > > diff --git a/target/s390x/kvm.c b/target/s390x/kvm.c > index 7a892d663d..84b40572f2 100644 > --- a/target/s390x/kvm.c > +++ b/target/s390x/kvm.c > @@ -161,8 +161,6 @@ static int cap_protected; > > static int active_cmma; > > -static void *legacy_s390_alloc(size_t size, uint64_t *align, bool shared); > - > static int kvm_s390_query_mem_limit(uint64_t *memory_limit) > { > struct kvm_device_attr attr = { > @@ -349,6 +347,11 @@ int kvm_arch_init(MachineState *ms, KVMState *s) > "please use kernel 3.15 or newer"); > return -1; > } > + if (!kvm_check_extension(s, KVM_CAP_S390_COW)) { > + error_report("KVM is missing capability KVM_CAP_S390_COW - " > + "unsupported environment"); > + return -1; > + } > > cap_sync_regs = kvm_check_extension(s, KVM_CAP_SYNC_REGS); > cap_async_pf = kvm_check_extension(s, KVM_CAP_ASYNC_PF); > @@ -357,11 +360,6 @@ int kvm_arch_init(MachineState *ms, KVMState *s) > cap_vcpu_resets = kvm_check_extension(s, KVM_CAP_S390_VCPU_RESETS); > cap_protected = kvm_check_extension(s, KVM_CAP_S390_PROTECTED); > > - if (!kvm_check_extension(s, KVM_CAP_S390_GMAP) > - || !kvm_check_extension(s, KVM_CAP_S390_COW)) { > - phys_mem_set_alloc(legacy_s390_alloc); > - } > - > kvm_vm_enable_cap(s, KVM_CAP_S390_USER_SIGP, 0); > kvm_vm_enable_cap(s, KVM_CAP_S390_VECTOR_REGISTERS, 0); > kvm_vm_enable_cap(s, KVM_CAP_S390_USER_STSI, 0); > @@ -889,37 +887,6 @@ int kvm_s390_mem_op_pv(S390CPU *cpu, uint64_t offset, void *hostbuf, > return ret; > } > > -/* > - * Legacy layout for s390: > - * Older S390 KVM requires the topmost vma of the RAM to be > - * smaller than an system defined value, which is at least 256GB. > - * Larger systems have larger values. We put the guest between > - * the end of data segment (system break) and this value. We > - * use 32GB as a base to have enough room for the system break > - * to grow. We also have to use MAP parameters that avoid > - * read-only mapping of guest pages. > - */ > -static void *legacy_s390_alloc(size_t size, uint64_t *align, bool shared) > -{ > - static void *mem; > - > - if (mem) { > - /* we only support one allocation, which is enough for initial ram */ > - return NULL; > - } > - > - mem = mmap((void *) 0x800000000ULL, size, > - PROT_EXEC|PROT_READ|PROT_WRITE, > - MAP_SHARED | MAP_ANONYMOUS | MAP_FIXED, -1, 0); > - if (mem == MAP_FAILED) { > - mem = NULL; > - } > - if (mem && align) { > - *align = QEMU_VMALLOC_ALIGN; > - } > - return mem; > -} > - > static uint8_t const *sw_bp_inst; > static uint8_t sw_bp_ilen; >
