Merge remote-tracking branch 'remotes/dgibson/tags/ppc-next-20151023' into staging

ppc patch queue - 2015-10-23

sPAPR highlights:
  * Allow VFIO devices on the spapr-pci-host-bridge
  * Allow virtio VGA
  * Safer handling of HTAB allocation
  * ibm,pa-features device tree property

non-sPAPR highlights:
  * Categorization of many ppc specific devices in help output
  * Tweaks to MMU type constants

# gpg: Signature made Fri 23 Oct 2015 07:27:56 BST using RSA key ID 20D9B392
# gpg: Good signature from "David Gibson <david@gibson.dropbear.id.au>"
# gpg:                 aka "David Gibson (Red Hat) <dgibson@redhat.com>"
# gpg:                 aka "David Gibson (ozlabs.org) <dgibson@ozlabs.org>"
# gpg: WARNING: This key is not certified with sufficiently trusted signatures!
# gpg:          It is not certain that the signature belongs to the owner.
# Primary key fingerprint: 75F4 6586 AE61 A66C C44E  87DC 6C38 CACA 20D9 B392

* remotes/dgibson/tags/ppc-next-20151023: (21 commits)
  prep: do not use CPU_LOG_IOPORT, convert to tracepoints
  openpic: add to misc category
  macio-nvram: add to misc category
  macio: add to bridge category
  uninorth: add to bridge category
  macio-ide: add to storage category
  cuda: add to bridge category
  grackle: add to bridge category
  escc: add to input category
  cmd646: add to storage category
  adb: add to input category
  ppc/spapr: Add "ibm,pa-features" property to the device-tree
  ppc: Add mmu_model defines for arch 2.03 and 2.07
  hw/scsi/spapr_vscsi: Remove superfluous memset
  spapr_pci: Allow VFIO devices to work on the normal PCI host bridge
  spapr_iommu: Provide a function to switch a TCE table to allowing VFIO
  spapr_iommu: Rename vfio_accel parameter
  spapr_pci: Allow PCI host bridge DMA window to be configured
  spapr: Add "slb-size" property to CPU device tree nodes
  spapr: Abort when HTAB of requested size isn't allocated
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

16 files changed, 136 insertions, 40 deletions

diff --git a/hw/char/escc.c b/hw/char/escc.c
index ba653ef..9816154 100644
--- a/hw/char/escc.c
+++ b/hw/char/escc.c
@@ -1035,6 +1035,7 @@ static void escc_class_init(ObjectClass *klass, void *data)
     dc->reset = escc_reset;
     dc->vmsd = &vmstate_escc;
     dc->props = escc_properties;
+    set_bit(DEVICE_CATEGORY_INPUT, dc->categories);
 }
 
 static const TypeInfo escc_info = {
diff --git a/hw/ide/cmd646.c b/hw/ide/cmd646.c
index 66fb9d9..27f3da2 100644
--- a/hw/ide/cmd646.c
+++ b/hw/ide/cmd646.c
@@ -417,6 +417,7 @@ static void cmd646_ide_class_init(ObjectClass *klass, void *data)
     k->config_read = cmd646_pci_config_read;
     k->config_write = cmd646_pci_config_write;
     dc->props = cmd646_ide_properties;
+    set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
 }
 
 static const TypeInfo cmd646_ide_info = {
diff --git a/hw/ide/macio.c b/hw/ide/macio.c
index 66ac2ba..893c9b9 100644
--- a/hw/ide/macio.c
+++ b/hw/ide/macio.c
@@ -590,6 +590,7 @@ static void macio_ide_class_init(ObjectClass *oc, void *data)
     dc->realize = macio_ide_realizefn;
     dc->reset = macio_ide_reset;
     dc->vmsd = &vmstate_pmac;
+    set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
 }
 
 static const TypeInfo macio_ide_type_info = {
diff --git a/hw/input/adb.c b/hw/input/adb.c
index a18eea2..09eead9 100644
--- a/hw/input/adb.c
+++ b/hw/input/adb.c
@@ -362,6 +362,7 @@ static void adb_kbd_class_init(ObjectClass *oc, void *data)
 
     akc->parent_realize = dc->realize;
     dc->realize = adb_kbd_realizefn;
+    set_bit(DEVICE_CATEGORY_INPUT, dc->categories);
 
     adc->devreq = adb_kbd_request;
     dc->reset = adb_kbd_reset;
@@ -566,6 +567,7 @@ static void adb_mouse_class_init(ObjectClass *oc, void *data)
 
     amc->parent_realize = dc->realize;
     dc->realize = adb_mouse_realizefn;
+    set_bit(DEVICE_CATEGORY_INPUT, dc->categories);
 
     adc->devreq = adb_mouse_request;
     dc->reset = adb_mouse_reset;
diff --git a/hw/intc/openpic.c b/hw/intc/openpic.c
index 14ab0e3..bfcf155 100644
--- a/hw/intc/openpic.c
+++ b/hw/intc/openpic.c
@@ -1643,6 +1643,7 @@ static void openpic_class_init(ObjectClass *oc, void *data)
     dc->props = openpic_properties;
     dc->reset = openpic_reset;
     dc->vmsd = &vmstate_openpic;
+    set_bit(DEVICE_CATEGORY_MISC, dc->categories);
 }
 
 static const TypeInfo openpic_info = {
diff --git a/hw/intc/openpic_kvm.c b/hw/intc/openpic_kvm.c
index f7cac58..649f476 100644
--- a/hw/intc/openpic_kvm.c
+++ b/hw/intc/openpic_kvm.c
@@ -275,6 +275,7 @@ static void kvm_openpic_class_init(ObjectClass *oc, void *data)
     dc->realize = kvm_openpic_realize;
     dc->props = kvm_openpic_properties;
     dc->reset = kvm_openpic_reset;
+    set_bit(DEVICE_CATEGORY_MISC, dc->categories);
 }
 
 static const TypeInfo kvm_openpic_info = {
diff --git a/hw/misc/macio/cuda.c b/hw/misc/macio/cuda.c
index 5d7043e..0fd75b3 100644
--- a/hw/misc/macio/cuda.c
+++ b/hw/misc/macio/cuda.c
@@ -738,6 +738,7 @@ static void cuda_class_init(ObjectClass *oc, void *data)
     dc->reset = cuda_reset;
     dc->vmsd = &vmstate_cuda;
     dc->props = cuda_properties;
+    set_bit(DEVICE_CATEGORY_BRIDGE, dc->categories);
 }
 
 static const TypeInfo cuda_type_info = {
diff --git a/hw/misc/macio/macio.c b/hw/misc/macio/macio.c
index c661f86..adb990e 100644
--- a/hw/misc/macio/macio.c
+++ b/hw/misc/macio/macio.c
@@ -393,6 +393,7 @@ static void macio_class_init(ObjectClass *klass, void *data)
     k->vendor_id = PCI_VENDOR_ID_APPLE;
     k->class_id = PCI_CLASS_OTHERS << 8;
     dc->props = macio_properties;
+    set_bit(DEVICE_CATEGORY_BRIDGE, dc->categories);
 }
 
 static const TypeInfo macio_oldworld_type_info = {
diff --git a/hw/nvram/mac_nvram.c b/hw/nvram/mac_nvram.c
index d35f8a3..9f16566 100644
--- a/hw/nvram/mac_nvram.c
+++ b/hw/nvram/mac_nvram.c
@@ -123,6 +123,7 @@ static void macio_nvram_class_init(ObjectClass *oc, void *data)
     dc->reset = macio_nvram_reset;
     dc->vmsd = &vmstate_macio_nvram;
     dc->props = macio_nvram_properties;
+    set_bit(DEVICE_CATEGORY_MISC, dc->categories);
 }
 
 static const TypeInfo macio_nvram_type_info = {
diff --git a/hw/pci-host/grackle.c b/hw/pci-host/grackle.c
index bfe707a..ea31b72 100644
--- a/hw/pci-host/grackle.c
+++ b/hw/pci-host/grackle.c
@@ -146,8 +146,10 @@ static const TypeInfo grackle_pci_info = {
 static void pci_grackle_class_init(ObjectClass *klass, void *data)
 {
     SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
+    DeviceClass *dc = DEVICE_CLASS(klass);
 
     k->init = pci_grackle_init_device;
+    set_bit(DEVICE_CATEGORY_BRIDGE, dc->categories);
 }
 
 static const TypeInfo grackle_pci_host_info = {
diff --git a/hw/pci-host/uninorth.c b/hw/pci-host/uninorth.c
index f0144eb..215b64f 100644
--- a/hw/pci-host/uninorth.c
+++ b/hw/pci-host/uninorth.c
@@ -446,8 +446,10 @@ static const TypeInfo unin_internal_pci_host_info = {
 static void pci_unin_main_class_init(ObjectClass *klass, void *data)
 {
     SysBusDeviceClass *sbc = SYS_BUS_DEVICE_CLASS(klass);
+    DeviceClass *dc = DEVICE_CLASS(klass);
 
     sbc->init = pci_unin_main_init_device;
+    set_bit(DEVICE_CATEGORY_BRIDGE, dc->categories);
 }
 
 static const TypeInfo pci_unin_main_info = {
@@ -460,8 +462,10 @@ static const TypeInfo pci_unin_main_info = {
 static void pci_u3_agp_class_init(ObjectClass *klass, void *data)
 {
     SysBusDeviceClass *sbc = SYS_BUS_DEVICE_CLASS(klass);
+    DeviceClass *dc = DEVICE_CLASS(klass);
 
     sbc->init = pci_u3_agp_init_device;
+    set_bit(DEVICE_CATEGORY_BRIDGE, dc->categories);
 }
 
 static const TypeInfo pci_u3_agp_info = {
@@ -474,8 +478,10 @@ static const TypeInfo pci_u3_agp_info = {
 static void pci_unin_agp_class_init(ObjectClass *klass, void *data)
 {
     SysBusDeviceClass *sbc = SYS_BUS_DEVICE_CLASS(klass);
+    DeviceClass *dc = DEVICE_CLASS(klass);
 
     sbc->init = pci_unin_agp_init_device;
+    set_bit(DEVICE_CATEGORY_BRIDGE, dc->categories);
 }
 
 static const TypeInfo pci_unin_agp_info = {
@@ -488,8 +494,10 @@ static const TypeInfo pci_unin_agp_info = {
 static void pci_unin_internal_class_init(ObjectClass *klass, void *data)
 {
     SysBusDeviceClass *sbc = SYS_BUS_DEVICE_CLASS(klass);
+    DeviceClass *dc = DEVICE_CLASS(klass);
 
     sbc->init = pci_unin_internal_init_device;
+    set_bit(DEVICE_CATEGORY_BRIDGE, dc->categories);
 }
 
 static const TypeInfo pci_unin_internal_info = {
diff --git a/hw/ppc/prep.c b/hw/ppc/prep.c
index d95222b..5ad28f7 100644
--- a/hw/ppc/prep.c
+++ b/hw/ppc/prep.c
@@ -42,11 +42,9 @@
 #include "sysemu/arch_init.h"
 #include "sysemu/qtest.h"
 #include "exec/address-spaces.h"
+#include "trace.h"
 #include "elf.h"
 
-//#define HARD_DEBUG_PPC_IO
-//#define DEBUG_PPC_IO
-
 /* SMP is not enabled, for now */
 #define MAX_CPUS 1
 
@@ -57,26 +55,6 @@
 #define KERNEL_LOAD_ADDR 0x01000000
 #define INITRD_LOAD_ADDR 0x01800000
 
-#if defined (HARD_DEBUG_PPC_IO) && !defined (DEBUG_PPC_IO)
-#define DEBUG_PPC_IO
-#endif
-
-#if defined (HARD_DEBUG_PPC_IO)
-#define PPC_IO_DPRINTF(fmt, ...)                         \
-do {                                                     \
-    if (qemu_loglevel_mask(CPU_LOG_IOPORT)) {            \
-        qemu_log("%s: " fmt, __func__ , ## __VA_ARGS__); \
-    } else {                                             \
-        printf("%s : " fmt, __func__ , ## __VA_ARGS__);  \
-    }                                                    \
-} while (0)
-#elif defined (DEBUG_PPC_IO)
-#define PPC_IO_DPRINTF(fmt, ...) \
-qemu_log_mask(CPU_LOG_IOPORT, fmt, ## __VA_ARGS__)
-#else
-#define PPC_IO_DPRINTF(fmt, ...) do { } while (0)
-#endif
-
 /* Constants for devices init */
 static const int ide_iobase[2] = { 0x1f0, 0x170 };
 static const int ide_iobase2[2] = { 0x3f6, 0x376 };
@@ -199,8 +177,7 @@ static void PREP_io_800_writeb (void *opaque, uint32_t addr, uint32_t val)
 {
     sysctrl_t *sysctrl = opaque;
 
-    PPC_IO_DPRINTF("0x%08" PRIx32 " => 0x%02" PRIx32 "\n",
-                   addr - PPC_IO_BASE, val);
+    trace_prep_io_800_writeb(addr - PPC_IO_BASE, val);
     switch (addr) {
     case 0x0092:
         /* Special port 92 */
@@ -327,8 +304,7 @@ static uint32_t PREP_io_800_readb (void *opaque, uint32_t addr)
         printf("ERROR: unaffected IO port: %04" PRIx32 " read\n", addr);
         break;
     }
-    PPC_IO_DPRINTF("0x%08" PRIx32 " <= 0x%02" PRIx32 "\n",
-                   addr - PPC_IO_BASE, retval);
+    trace_prep_io_800_readb(addr - PPC_IO_BASE, retval);
 
     return retval;
 }
diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index 3852ad1..e1202ce 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -597,6 +597,24 @@ static void spapr_populate_cpu_dt(CPUState *cs, void *fdt, int offset,
     uint32_t vcpus_per_socket = smp_threads * smp_cores;
     uint32_t pft_size_prop[] = {0, cpu_to_be32(spapr->htab_shift)};
 
+    /* Note: we keep CI large pages off for now because a 64K capable guest
+     * provisioned with large pages might otherwise try to map a qemu
+     * framebuffer (or other kind of memory mapped PCI BAR) using 64K pages
+     * even if that qemu runs on a 4k host.
+     *
+     * We can later add this bit back when we are confident this is not
+     * an issue (!HV KVM or 64K host)
+     */
+    uint8_t pa_features_206[] = { 6, 0,
+        0xf6, 0x1f, 0xc7, 0x00, 0x80, 0xc0 };
+    uint8_t pa_features_207[] = { 24, 0,
+        0xf6, 0x1f, 0xc7, 0xc0, 0x80, 0xf0,
+        0x80, 0x00, 0x00, 0x00, 0x00, 0x00,
+        0x00, 0x00, 0x00, 0x00, 0x80, 0x00,
+        0x80, 0x00, 0x80, 0x00, 0x80, 0x00 };
+    uint8_t *pa_features;
+    size_t pa_size;
+
     _FDT((fdt_setprop_cell(fdt, offset, "reg", index)));
     _FDT((fdt_setprop_string(fdt, offset, "device_type", "cpu")));
 
@@ -625,6 +643,7 @@ static void spapr_populate_cpu_dt(CPUState *cs, void *fdt, int offset,
 
     _FDT((fdt_setprop_cell(fdt, offset, "timebase-frequency", tbfreq)));
     _FDT((fdt_setprop_cell(fdt, offset, "clock-frequency", cpufreq)));
+    _FDT((fdt_setprop_cell(fdt, offset, "slb-size", env->slb_nr)));
     _FDT((fdt_setprop_cell(fdt, offset, "ibm,slb-size", env->slb_nr)));
     _FDT((fdt_setprop_string(fdt, offset, "status", "okay")));
     _FDT((fdt_setprop(fdt, offset, "64-bit", NULL, 0)));
@@ -662,6 +681,19 @@ static void spapr_populate_cpu_dt(CPUState *cs, void *fdt, int offset,
                           page_sizes_prop, page_sizes_prop_size)));
     }
 
+    /* Do the ibm,pa-features property, adjust it for ci-large-pages */
+    if (env->mmu_model == POWERPC_MMU_2_06) {
+        pa_features = pa_features_206;
+        pa_size = sizeof(pa_features_206);
+    } else /* env->mmu_model == POWERPC_MMU_2_07 */ {
+        pa_features = pa_features_207;
+        pa_size = sizeof(pa_features_207);
+    }
+    if (env->ci_large_pages) {
+        pa_features[3] |= 0x20;
+    }
+    _FDT((fdt_setprop(fdt, offset, "ibm,pa-features", pa_features, pa_size)));
+
     _FDT((fdt_setprop_cell(fdt, offset, "ibm,chip-id",
                            cs->cpu_index / vcpus_per_socket)));
 
@@ -979,7 +1011,7 @@ static void emulate_spapr_hypercall(PowerPCCPU *cpu)
 #define CLEAN_HPTE(_hpte)  ((*(uint64_t *)(_hpte)) &= tswap64(~HPTE64_V_HPTE_DIRTY))
 #define DIRTY_HPTE(_hpte)  ((*(uint64_t *)(_hpte)) |= tswap64(HPTE64_V_HPTE_DIRTY))
 
-static void spapr_reset_htab(sPAPRMachineState *spapr)
+static void spapr_alloc_htab(sPAPRMachineState *spapr)
 {
     long shift;
     int index;
@@ -992,20 +1024,47 @@ static void spapr_reset_htab(sPAPRMachineState *spapr)
 
     if (shift > 0) {
         /* Kernel handles htab, we don't need to allocate one */
+        if (shift != spapr->htab_shift) {
+            error_setg(&error_abort, "Failed to allocate HTAB of requested size, try with smaller maxmem");
+        }
+
         spapr->htab_shift = shift;
         kvmppc_kern_htab = true;
+    } else {
+        /* Allocate htab */
+        spapr->htab = qemu_memalign(HTAB_SIZE(spapr), HTAB_SIZE(spapr));
+
+        /* And clear it */
+        memset(spapr->htab, 0, HTAB_SIZE(spapr));
+
+        for (index = 0; index < HTAB_SIZE(spapr) / HASH_PTE_SIZE_64; index++) {
+            DIRTY_HPTE(HPTE(spapr->htab, index));
+        }
+    }
+}
+
+/*
+ * Clear HTAB entries during reset.
+ *
+ * If host kernel has allocated HTAB, KVM_PPC_ALLOCATE_HTAB ioctl is
+ * used to clear HTAB. Otherwise QEMU-allocated HTAB is cleared manually.
+ */
+static void spapr_reset_htab(sPAPRMachineState *spapr)
+{
+    long shift;
+    int index;
+
+    shift = kvmppc_reset_htab(spapr->htab_shift);
+    if (shift > 0) {
+        if (shift != spapr->htab_shift) {
+            error_setg(&error_abort, "Requested HTAB allocation failed during reset");
+        }
 
         /* Tell readers to update their file descriptor */
         if (spapr->htab_fd >= 0) {
             spapr->htab_fd_stale = true;
         }
     } else {
-        if (!spapr->htab) {
-            /* Allocate an htab if we don't yet have one */
-            spapr->htab = qemu_memalign(HTAB_SIZE(spapr), HTAB_SIZE(spapr));
-        }
-
-        /* And clear it */
         memset(spapr->htab, 0, HTAB_SIZE(spapr));
 
         for (index = 0; index < HTAB_SIZE(spapr) / HASH_PTE_SIZE_64; index++) {
@@ -1710,6 +1769,7 @@ static void ppc_spapr_init(MachineState *machine)
         }
         spapr->htab_shift++;
     }
+    spapr_alloc_htab(spapr);
 
     /* Set up Interrupt Controller before we create the VCPUs */
     spapr->icp = xics_system_init(machine,
diff --git a/hw/ppc/spapr_iommu.c b/hw/ppc/spapr_iommu.c
index f61504e..ed28565 100644
--- a/hw/ppc/spapr_iommu.c
+++ b/hw/ppc/spapr_iommu.c
@@ -146,7 +146,7 @@ static int spapr_tce_table_realize(DeviceState *dev)
         tcet->table = kvmppc_create_spapr_tce(tcet->liobn,
                                               window_size,
                                               &tcet->fd,
-                                              tcet->vfio_accel);
+                                              tcet->need_vfio);
     }
 
     if (!tcet->table) {
@@ -168,11 +168,43 @@ static int spapr_tce_table_realize(DeviceState *dev)
     return 0;
 }
 
+void spapr_tce_set_need_vfio(sPAPRTCETable *tcet, bool need_vfio)
+{
+    size_t table_size = tcet->nb_table * sizeof(uint64_t);
+    void *newtable;
+
+    if (need_vfio == tcet->need_vfio) {
+        /* Nothing to do */
+        return;
+    }
+
+    if (!need_vfio) {
+        /* FIXME: We don't support transition back to KVM accelerated
+         * TCEs yet */
+        return;
+    }
+
+    tcet->need_vfio = true;
+
+    if (tcet->fd < 0) {
+        /* Table is already in userspace, nothing to be do */
+        return;
+    }
+
+    newtable = g_malloc(table_size);
+    memcpy(newtable, tcet->table, table_size);
+
+    kvmppc_remove_spapr_tce(tcet->table, tcet->fd, tcet->nb_table);
+
+    tcet->fd = -1;
+    tcet->table = newtable;
+}
+
 sPAPRTCETable *spapr_tce_new_table(DeviceState *owner, uint32_t liobn,
                                    uint64_t bus_offset,
                                    uint32_t page_shift,
                                    uint32_t nb_table,
-                                   bool vfio_accel)
+                                   bool need_vfio)
 {
     sPAPRTCETable *tcet;
     char tmp[64];
@@ -192,7 +224,7 @@ sPAPRTCETable *spapr_tce_new_table(DeviceState *owner, uint32_t liobn,
     tcet->bus_offset = bus_offset;
     tcet->page_shift = page_shift;
     tcet->nb_table = nb_table;
-    tcet->vfio_accel = vfio_accel;
+    tcet->need_vfio = need_vfio;
 
     snprintf(tmp, sizeof(tmp), "tce-table-%x", liobn);
     object_property_add_child(OBJECT(owner), tmp, OBJECT(tcet), NULL);
diff --git a/hw/ppc/spapr_pci.c b/hw/ppc/spapr_pci.c
index 617b7f3..55fa8db 100644
--- a/hw/ppc/spapr_pci.c
+++ b/hw/ppc/spapr_pci.c
@@ -1083,6 +1083,12 @@ static void spapr_phb_add_pci_device(sPAPRDRConnector *drc,
     void *fdt = NULL;
     int fdt_start_offset = 0, fdt_size;
 
+    if (object_dynamic_cast(OBJECT(pdev), "vfio-pci")) {
+        sPAPRTCETable *tcet = spapr_tce_find_by_liobn(phb->dma_liobn);
+
+        spapr_tce_set_need_vfio(tcet, true);
+    }
+
     if (dev->hotplugged) {
         fdt = create_device_tree(&fdt_size);
         fdt_start_offset = spapr_create_pci_child_dt(phb, pdev, fdt, 0);
@@ -1387,7 +1393,7 @@ static void spapr_phb_finish_realize(sPAPRPHBState *sphb, Error **errp)
     sPAPRTCETable *tcet;
     uint32_t nb_table;
 
-    nb_table = SPAPR_PCI_DMA32_SIZE >> SPAPR_TCE_PAGE_SHIFT;
+    nb_table = sphb->dma_win_size >> SPAPR_TCE_PAGE_SHIFT;
     tcet = spapr_tce_new_table(DEVICE(sphb), sphb->dma_liobn,
                                0, SPAPR_TCE_PAGE_SHIFT, nb_table, false);
     if (!tcet) {
@@ -1397,7 +1403,7 @@ static void spapr_phb_finish_realize(sPAPRPHBState *sphb, Error **errp)
     }
 
     /* Register default 32bit DMA window */
-    memory_region_add_subregion(&sphb->iommu_root, 0,
+    memory_region_add_subregion(&sphb->iommu_root, sphb->dma_win_addr,
                                 spapr_tce_get_iommu(tcet));
 }
 
@@ -1430,6 +1436,9 @@ static Property spapr_phb_properties[] = {
                        SPAPR_PCI_IO_WIN_SIZE),
     DEFINE_PROP_BOOL("dynamic-reconfiguration", sPAPRPHBState, dr_enabled,
                      true),
+    /* Default DMA window is 0..1GB */
+    DEFINE_PROP_UINT64("dma_win_addr", sPAPRPHBState, dma_win_addr, 0),
+    DEFINE_PROP_UINT64("dma_win_size", sPAPRPHBState, dma_win_size, 0x40000000),
     DEFINE_PROP_END_OF_LIST(),
 };
 
diff --git a/hw/scsi/spapr_vscsi.c b/hw/scsi/spapr_vscsi.c
index 891424f..f4f5140 100644
--- a/hw/scsi/spapr_vscsi.c
+++ b/hw/scsi/spapr_vscsi.c
@@ -750,7 +750,6 @@ static void vscsi_report_luns(VSCSIState *s, vscsi_req *req)
     len = n+8;
 
     resp_data = g_malloc0(len);
-    memset(resp_data, 0, len);
     stl_be_p(resp_data, n);
     i = found_lun0 ? 8 : 16;
     QTAILQ_FOREACH(kid, &s->bus.qbus.children, sibling) {