From 996e7e4b72f48c2f878e269bb9252d97129b6f73 Mon Sep 17 00:00:00 2001 From: David Hildenbrand Date: Wed, 3 Mar 2021 14:09:15 +0100 Subject: [PATCH] s390x/kvm: Get rid of legacy_s390_alloc() 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 Suggested-by: Thomas Huth Cc: Paolo Bonzini Cc: Richard Henderson Cc: Halil Pasic Cc: Cornelia Huck Cc: Christian Borntraeger Cc: Thomas Huth Cc: Igor Mammedov Cc: Peter Xu Signed-off-by: David Hildenbrand Reviewed-by: Thomas Huth Reviewed-by: Igor Mammedov Message-Id: <20210303130916.22553-2-david@redhat.com> Signed-off-by: Cornelia Huck --- 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 73f816a722..4fb3bbfef5 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;