| Message ID | 1465535688-29001-1-git-send-email-bharata@linux.vnet.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Quoting Bharata B Rao (2016-06-10 00:14:48) > Memory hotplug can fail for some combinations of RAM and maxmem when > DDW is enabled in the presence of devices like nec-usb-xhci. DDW depends > on maximum addressable memory returned by guest and this value is currently > being calculated wrongly by the guest kernel routine memory_hotplug_max(). > While there is an attempt to fix the guest kernel, this patch works > around the problem within QEMU itself. > > memory_hotplug_max() routine in the guest kernel arrives at max > addressable memory by multiplying lmb-size with the lmb-count obtained > from ibm,dynamic-memory property. There are two assumptions here: > > - All LMBs are part of ibm,dynamic memory: This is not true for PowerKVM > where only hot-pluggable LMBs are present in this property. > - The memory area comprising of RAM and hotplug region is contiguous: This > needn't be true always for PowerKVM as there can be gap between > boot time RAM and hotplug region. > > To work around this guest kernel bug, ensure that ibm,dynamic-memory > has information about all the LMBs (RMA, boot-time LMBs, future > hotpluggable LMBs, and dummy LMBs to cover the gap between RAM and > hotpluggable region). > > RMA is represented separately by memory@0 node. Hence mark RMA LMBs > and also the LMBs for the gap b/n RAM and hotpluggable region as > reserved and as having no valid DRC so that these LMBs are not considered > by the guest. > > Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com> Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com> > --- > Changes in v4: > > - Included address information for all LMBs in ibm,dynamic-memory. > - Use both RESERVED and DRC_INVALID flag bits for non-hotpluggable LMBs. > > v3: https://lists.gnu.org/archive/html/qemu-ppc/2016-06/msg00187.html > > hw/ppc/spapr.c | 57 ++++++++++++++++++++++++++++++++------------------ > include/hw/ppc/spapr.h | 6 ++++-- > 2 files changed, 41 insertions(+), 22 deletions(-) > > diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c > index 0636642..9a4a803 100644 > --- a/hw/ppc/spapr.c > +++ b/hw/ppc/spapr.c > @@ -762,14 +762,17 @@ static int spapr_populate_drconf_memory(sPAPRMachineState *spapr, void *fdt) > int ret, i, offset; > uint64_t lmb_size = SPAPR_MEMORY_BLOCK_SIZE; > uint32_t prop_lmb_size[] = {0, cpu_to_be32(lmb_size)}; > - uint32_t nr_lmbs = (machine->maxram_size - machine->ram_size)/lmb_size; > + uint32_t hotplug_lmb_start = spapr->hotplug_memory.base / lmb_size; > + uint32_t nr_lmbs = (spapr->hotplug_memory.base + > + memory_region_size(&spapr->hotplug_memory.mr)) / > + lmb_size; > uint32_t *int_buf, *cur_index, buf_len; > int nr_nodes = nb_numa_nodes ? nb_numa_nodes : 1; > > /* > - * Don't create the node if there are no DR LMBs. > + * Don't create the node if there is no hotpluggable memory > */ > - if (!nr_lmbs) { > + if (machine->ram_size == machine->maxram_size) { > return 0; > } > > @@ -803,26 +806,40 @@ static int spapr_populate_drconf_memory(sPAPRMachineState *spapr, void *fdt) > int_buf[0] = cpu_to_be32(nr_lmbs); > cur_index++; > for (i = 0; i < nr_lmbs; i++) { > - sPAPRDRConnector *drc; > - sPAPRDRConnectorClass *drck; > - uint64_t addr = i * lmb_size + spapr->hotplug_memory.base;; > + uint64_t addr = i * lmb_size; > uint32_t *dynamic_memory = cur_index; > > - drc = spapr_dr_connector_by_id(SPAPR_DR_CONNECTOR_TYPE_LMB, > - addr/lmb_size); > - g_assert(drc); > - drck = SPAPR_DR_CONNECTOR_GET_CLASS(drc); > - > - dynamic_memory[0] = cpu_to_be32(addr >> 32); > - dynamic_memory[1] = cpu_to_be32(addr & 0xffffffff); > - dynamic_memory[2] = cpu_to_be32(drck->get_index(drc)); > - dynamic_memory[3] = cpu_to_be32(0); /* reserved */ > - dynamic_memory[4] = cpu_to_be32(numa_get_node(addr, NULL)); > - if (addr < machine->ram_size || > - memory_region_present(get_system_memory(), addr)) { > - dynamic_memory[5] = cpu_to_be32(SPAPR_LMB_FLAGS_ASSIGNED); > + if (i >= hotplug_lmb_start) { > + sPAPRDRConnector *drc; > + sPAPRDRConnectorClass *drck; > + > + drc = spapr_dr_connector_by_id(SPAPR_DR_CONNECTOR_TYPE_LMB, i); > + g_assert(drc); > + drck = SPAPR_DR_CONNECTOR_GET_CLASS(drc); > + > + dynamic_memory[0] = cpu_to_be32(addr >> 32); > + dynamic_memory[1] = cpu_to_be32(addr & 0xffffffff); > + dynamic_memory[2] = cpu_to_be32(drck->get_index(drc)); > + dynamic_memory[3] = cpu_to_be32(0); /* reserved */ > + dynamic_memory[4] = cpu_to_be32(numa_get_node(addr, NULL)); > + if (memory_region_present(get_system_memory(), addr)) { > + dynamic_memory[5] = cpu_to_be32(SPAPR_LMB_FLAGS_ASSIGNED); > + } else { > + dynamic_memory[5] = cpu_to_be32(0); > + } > } else { > - dynamic_memory[5] = cpu_to_be32(0); > + /* > + * LMB information for RMA, boot time RAM and gap b/n RAM and > + * hotplug memory region -- all these are marked as reserved > + * and as having no valid DRC. > + */ > + dynamic_memory[0] = cpu_to_be32(addr >> 32); > + dynamic_memory[1] = cpu_to_be32(addr & 0xffffffff); > + dynamic_memory[2] = cpu_to_be32(0); > + dynamic_memory[3] = cpu_to_be32(0); /* reserved */ > + dynamic_memory[4] = cpu_to_be32(-1); > + dynamic_memory[5] = cpu_to_be32(SPAPR_LMB_FLAGS_RESERVED | > + SPAPR_LMB_FLAGS_DRC_INVALID); > } > > cur_index += SPAPR_DR_LMB_LIST_ENTRY_SIZE; > diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h > index 971df3d..3ac85c0 100644 > --- a/include/hw/ppc/spapr.h > +++ b/include/hw/ppc/spapr.h > @@ -620,9 +620,11 @@ int spapr_rng_populate_dt(void *fdt); > #define SPAPR_DR_LMB_LIST_ENTRY_SIZE 6 > > /* > - * This flag value defines the LMB as assigned in ibm,dynamic-memory > - * property under ibm,dynamic-reconfiguration-memory node. > + * Defines for flag value in ibm,dynamic-memory property under > + * ibm,dynamic-reconfiguration-memory node. > */ > #define SPAPR_LMB_FLAGS_ASSIGNED 0x00000008 > +#define SPAPR_LMB_FLAGS_DRC_INVALID 0x00000020 > +#define SPAPR_LMB_FLAGS_RESERVED 0x00000080 > > #endif /* !defined (__HW_SPAPR_H__) */ > -- > 2.1.0 >
On 06/10/2016 12:14 AM, Bharata B Rao wrote: > Memory hotplug can fail for some combinations of RAM and maxmem when > DDW is enabled in the presence of devices like nec-usb-xhci. DDW depends > on maximum addressable memory returned by guest and this value is currently > being calculated wrongly by the guest kernel routine memory_hotplug_max(). > While there is an attempt to fix the guest kernel, this patch works > around the problem within QEMU itself. > > memory_hotplug_max() routine in the guest kernel arrives at max > addressable memory by multiplying lmb-size with the lmb-count obtained > from ibm,dynamic-memory property. There are two assumptions here: > > - All LMBs are part of ibm,dynamic memory: This is not true for PowerKVM > where only hot-pluggable LMBs are present in this property. > - The memory area comprising of RAM and hotplug region is contiguous: This > needn't be true always for PowerKVM as there can be gap between > boot time RAM and hotplug region. > > To work around this guest kernel bug, ensure that ibm,dynamic-memory > has information about all the LMBs (RMA, boot-time LMBs, future > hotpluggable LMBs, and dummy LMBs to cover the gap between RAM and > hotpluggable region). > > RMA is represented separately by memory@0 node. Hence mark RMA LMBs > and also the LMBs for the gap b/n RAM and hotpluggable region as > reserved and as having no valid DRC so that these LMBs are not considered > by the guest. > > Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com> Reviewed-by: Nathan Fontenot <nfont@linux.vnet.ibm.com> > --- > Changes in v4: > > - Included address information for all LMBs in ibm,dynamic-memory. > - Use both RESERVED and DRC_INVALID flag bits for non-hotpluggable LMBs. > > v3: https://lists.gnu.org/archive/html/qemu-ppc/2016-06/msg00187.html > > hw/ppc/spapr.c | 57 ++++++++++++++++++++++++++++++++------------------ > include/hw/ppc/spapr.h | 6 ++++-- > 2 files changed, 41 insertions(+), 22 deletions(-) > > diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c > index 0636642..9a4a803 100644 > --- a/hw/ppc/spapr.c > +++ b/hw/ppc/spapr.c > @@ -762,14 +762,17 @@ static int spapr_populate_drconf_memory(sPAPRMachineState *spapr, void *fdt) > int ret, i, offset; > uint64_t lmb_size = SPAPR_MEMORY_BLOCK_SIZE; > uint32_t prop_lmb_size[] = {0, cpu_to_be32(lmb_size)}; > - uint32_t nr_lmbs = (machine->maxram_size - machine->ram_size)/lmb_size; > + uint32_t hotplug_lmb_start = spapr->hotplug_memory.base / lmb_size; > + uint32_t nr_lmbs = (spapr->hotplug_memory.base + > + memory_region_size(&spapr->hotplug_memory.mr)) / > + lmb_size; > uint32_t *int_buf, *cur_index, buf_len; > int nr_nodes = nb_numa_nodes ? nb_numa_nodes : 1; > > /* > - * Don't create the node if there are no DR LMBs. > + * Don't create the node if there is no hotpluggable memory > */ > - if (!nr_lmbs) { > + if (machine->ram_size == machine->maxram_size) { > return 0; > } > > @@ -803,26 +806,40 @@ static int spapr_populate_drconf_memory(sPAPRMachineState *spapr, void *fdt) > int_buf[0] = cpu_to_be32(nr_lmbs); > cur_index++; > for (i = 0; i < nr_lmbs; i++) { > - sPAPRDRConnector *drc; > - sPAPRDRConnectorClass *drck; > - uint64_t addr = i * lmb_size + spapr->hotplug_memory.base;; > + uint64_t addr = i * lmb_size; > uint32_t *dynamic_memory = cur_index; > > - drc = spapr_dr_connector_by_id(SPAPR_DR_CONNECTOR_TYPE_LMB, > - addr/lmb_size); > - g_assert(drc); > - drck = SPAPR_DR_CONNECTOR_GET_CLASS(drc); > - > - dynamic_memory[0] = cpu_to_be32(addr >> 32); > - dynamic_memory[1] = cpu_to_be32(addr & 0xffffffff); > - dynamic_memory[2] = cpu_to_be32(drck->get_index(drc)); > - dynamic_memory[3] = cpu_to_be32(0); /* reserved */ > - dynamic_memory[4] = cpu_to_be32(numa_get_node(addr, NULL)); > - if (addr < machine->ram_size || > - memory_region_present(get_system_memory(), addr)) { > - dynamic_memory[5] = cpu_to_be32(SPAPR_LMB_FLAGS_ASSIGNED); > + if (i >= hotplug_lmb_start) { > + sPAPRDRConnector *drc; > + sPAPRDRConnectorClass *drck; > + > + drc = spapr_dr_connector_by_id(SPAPR_DR_CONNECTOR_TYPE_LMB, i); > + g_assert(drc); > + drck = SPAPR_DR_CONNECTOR_GET_CLASS(drc); > + > + dynamic_memory[0] = cpu_to_be32(addr >> 32); > + dynamic_memory[1] = cpu_to_be32(addr & 0xffffffff); > + dynamic_memory[2] = cpu_to_be32(drck->get_index(drc)); > + dynamic_memory[3] = cpu_to_be32(0); /* reserved */ > + dynamic_memory[4] = cpu_to_be32(numa_get_node(addr, NULL)); > + if (memory_region_present(get_system_memory(), addr)) { > + dynamic_memory[5] = cpu_to_be32(SPAPR_LMB_FLAGS_ASSIGNED); > + } else { > + dynamic_memory[5] = cpu_to_be32(0); > + } > } else { > - dynamic_memory[5] = cpu_to_be32(0); > + /* > + * LMB information for RMA, boot time RAM and gap b/n RAM and > + * hotplug memory region -- all these are marked as reserved > + * and as having no valid DRC. > + */ > + dynamic_memory[0] = cpu_to_be32(addr >> 32); > + dynamic_memory[1] = cpu_to_be32(addr & 0xffffffff); > + dynamic_memory[2] = cpu_to_be32(0); > + dynamic_memory[3] = cpu_to_be32(0); /* reserved */ > + dynamic_memory[4] = cpu_to_be32(-1); > + dynamic_memory[5] = cpu_to_be32(SPAPR_LMB_FLAGS_RESERVED | > + SPAPR_LMB_FLAGS_DRC_INVALID); > } > > cur_index += SPAPR_DR_LMB_LIST_ENTRY_SIZE; > diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h > index 971df3d..3ac85c0 100644 > --- a/include/hw/ppc/spapr.h > +++ b/include/hw/ppc/spapr.h > @@ -620,9 +620,11 @@ int spapr_rng_populate_dt(void *fdt); > #define SPAPR_DR_LMB_LIST_ENTRY_SIZE 6 > > /* > - * This flag value defines the LMB as assigned in ibm,dynamic-memory > - * property under ibm,dynamic-reconfiguration-memory node. > + * Defines for flag value in ibm,dynamic-memory property under > + * ibm,dynamic-reconfiguration-memory node. > */ > #define SPAPR_LMB_FLAGS_ASSIGNED 0x00000008 > +#define SPAPR_LMB_FLAGS_DRC_INVALID 0x00000020 > +#define SPAPR_LMB_FLAGS_RESERVED 0x00000080 > > #endif /* !defined (__HW_SPAPR_H__) */ >
On Fri, Jun 10, 2016 at 10:44:48AM +0530, Bharata B Rao wrote: > Memory hotplug can fail for some combinations of RAM and maxmem when > DDW is enabled in the presence of devices like nec-usb-xhci. DDW depends > on maximum addressable memory returned by guest and this value is currently > being calculated wrongly by the guest kernel routine memory_hotplug_max(). > While there is an attempt to fix the guest kernel, this patch works > around the problem within QEMU itself. > > memory_hotplug_max() routine in the guest kernel arrives at max > addressable memory by multiplying lmb-size with the lmb-count obtained > from ibm,dynamic-memory property. There are two assumptions here: > > - All LMBs are part of ibm,dynamic memory: This is not true for PowerKVM > where only hot-pluggable LMBs are present in this property. > - The memory area comprising of RAM and hotplug region is contiguous: This > needn't be true always for PowerKVM as there can be gap between > boot time RAM and hotplug region. > > To work around this guest kernel bug, ensure that ibm,dynamic-memory > has information about all the LMBs (RMA, boot-time LMBs, future > hotpluggable LMBs, and dummy LMBs to cover the gap between RAM and > hotpluggable region). > > RMA is represented separately by memory@0 node. Hence mark RMA LMBs > and also the LMBs for the gap b/n RAM and hotpluggable region as > reserved and as having no valid DRC so that these LMBs are not considered > by the guest. > > Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com> Applied to ppc-for-2.7, thanks. > --- > Changes in v4: > > - Included address information for all LMBs in ibm,dynamic-memory. > - Use both RESERVED and DRC_INVALID flag bits for non-hotpluggable LMBs. > > v3: https://lists.gnu.org/archive/html/qemu-ppc/2016-06/msg00187.html > > hw/ppc/spapr.c | 57 ++++++++++++++++++++++++++++++++------------------ > include/hw/ppc/spapr.h | 6 ++++-- > 2 files changed, 41 insertions(+), 22 deletions(-) > > diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c > index 0636642..9a4a803 100644 > --- a/hw/ppc/spapr.c > +++ b/hw/ppc/spapr.c > @@ -762,14 +762,17 @@ static int spapr_populate_drconf_memory(sPAPRMachineState *spapr, void *fdt) > int ret, i, offset; > uint64_t lmb_size = SPAPR_MEMORY_BLOCK_SIZE; > uint32_t prop_lmb_size[] = {0, cpu_to_be32(lmb_size)}; > - uint32_t nr_lmbs = (machine->maxram_size - machine->ram_size)/lmb_size; > + uint32_t hotplug_lmb_start = spapr->hotplug_memory.base / lmb_size; > + uint32_t nr_lmbs = (spapr->hotplug_memory.base + > + memory_region_size(&spapr->hotplug_memory.mr)) / > + lmb_size; > uint32_t *int_buf, *cur_index, buf_len; > int nr_nodes = nb_numa_nodes ? nb_numa_nodes : 1; > > /* > - * Don't create the node if there are no DR LMBs. > + * Don't create the node if there is no hotpluggable memory > */ > - if (!nr_lmbs) { > + if (machine->ram_size == machine->maxram_size) { > return 0; > } > > @@ -803,26 +806,40 @@ static int spapr_populate_drconf_memory(sPAPRMachineState *spapr, void *fdt) > int_buf[0] = cpu_to_be32(nr_lmbs); > cur_index++; > for (i = 0; i < nr_lmbs; i++) { > - sPAPRDRConnector *drc; > - sPAPRDRConnectorClass *drck; > - uint64_t addr = i * lmb_size + spapr->hotplug_memory.base;; > + uint64_t addr = i * lmb_size; > uint32_t *dynamic_memory = cur_index; > > - drc = spapr_dr_connector_by_id(SPAPR_DR_CONNECTOR_TYPE_LMB, > - addr/lmb_size); > - g_assert(drc); > - drck = SPAPR_DR_CONNECTOR_GET_CLASS(drc); > - > - dynamic_memory[0] = cpu_to_be32(addr >> 32); > - dynamic_memory[1] = cpu_to_be32(addr & 0xffffffff); > - dynamic_memory[2] = cpu_to_be32(drck->get_index(drc)); > - dynamic_memory[3] = cpu_to_be32(0); /* reserved */ > - dynamic_memory[4] = cpu_to_be32(numa_get_node(addr, NULL)); > - if (addr < machine->ram_size || > - memory_region_present(get_system_memory(), addr)) { > - dynamic_memory[5] = cpu_to_be32(SPAPR_LMB_FLAGS_ASSIGNED); > + if (i >= hotplug_lmb_start) { > + sPAPRDRConnector *drc; > + sPAPRDRConnectorClass *drck; > + > + drc = spapr_dr_connector_by_id(SPAPR_DR_CONNECTOR_TYPE_LMB, i); > + g_assert(drc); > + drck = SPAPR_DR_CONNECTOR_GET_CLASS(drc); > + > + dynamic_memory[0] = cpu_to_be32(addr >> 32); > + dynamic_memory[1] = cpu_to_be32(addr & 0xffffffff); > + dynamic_memory[2] = cpu_to_be32(drck->get_index(drc)); > + dynamic_memory[3] = cpu_to_be32(0); /* reserved */ > + dynamic_memory[4] = cpu_to_be32(numa_get_node(addr, NULL)); > + if (memory_region_present(get_system_memory(), addr)) { > + dynamic_memory[5] = cpu_to_be32(SPAPR_LMB_FLAGS_ASSIGNED); > + } else { > + dynamic_memory[5] = cpu_to_be32(0); > + } > } else { > - dynamic_memory[5] = cpu_to_be32(0); > + /* > + * LMB information for RMA, boot time RAM and gap b/n RAM and > + * hotplug memory region -- all these are marked as reserved > + * and as having no valid DRC. > + */ > + dynamic_memory[0] = cpu_to_be32(addr >> 32); > + dynamic_memory[1] = cpu_to_be32(addr & 0xffffffff); > + dynamic_memory[2] = cpu_to_be32(0); > + dynamic_memory[3] = cpu_to_be32(0); /* reserved */ > + dynamic_memory[4] = cpu_to_be32(-1); > + dynamic_memory[5] = cpu_to_be32(SPAPR_LMB_FLAGS_RESERVED | > + SPAPR_LMB_FLAGS_DRC_INVALID); > } > > cur_index += SPAPR_DR_LMB_LIST_ENTRY_SIZE; > diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h > index 971df3d..3ac85c0 100644 > --- a/include/hw/ppc/spapr.h > +++ b/include/hw/ppc/spapr.h > @@ -620,9 +620,11 @@ int spapr_rng_populate_dt(void *fdt); > #define SPAPR_DR_LMB_LIST_ENTRY_SIZE 6 > > /* > - * This flag value defines the LMB as assigned in ibm,dynamic-memory > - * property under ibm,dynamic-reconfiguration-memory node. > + * Defines for flag value in ibm,dynamic-memory property under > + * ibm,dynamic-reconfiguration-memory node. > */ > #define SPAPR_LMB_FLAGS_ASSIGNED 0x00000008 > +#define SPAPR_LMB_FLAGS_DRC_INVALID 0x00000020 > +#define SPAPR_LMB_FLAGS_RESERVED 0x00000080 > > #endif /* !defined (__HW_SPAPR_H__) */
diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c index 0636642..9a4a803 100644 --- a/hw/ppc/spapr.c +++ b/hw/ppc/spapr.c @@ -762,14 +762,17 @@ static int spapr_populate_drconf_memory(sPAPRMachineState *spapr, void *fdt) int ret, i, offset; uint64_t lmb_size = SPAPR_MEMORY_BLOCK_SIZE; uint32_t prop_lmb_size[] = {0, cpu_to_be32(lmb_size)}; - uint32_t nr_lmbs = (machine->maxram_size - machine->ram_size)/lmb_size; + uint32_t hotplug_lmb_start = spapr->hotplug_memory.base / lmb_size; + uint32_t nr_lmbs = (spapr->hotplug_memory.base + + memory_region_size(&spapr->hotplug_memory.mr)) / + lmb_size; uint32_t *int_buf, *cur_index, buf_len; int nr_nodes = nb_numa_nodes ? nb_numa_nodes : 1; /* - * Don't create the node if there are no DR LMBs. + * Don't create the node if there is no hotpluggable memory */ - if (!nr_lmbs) { + if (machine->ram_size == machine->maxram_size) { return 0; } @@ -803,26 +806,40 @@ static int spapr_populate_drconf_memory(sPAPRMachineState *spapr, void *fdt) int_buf[0] = cpu_to_be32(nr_lmbs); cur_index++; for (i = 0; i < nr_lmbs; i++) { - sPAPRDRConnector *drc; - sPAPRDRConnectorClass *drck; - uint64_t addr = i * lmb_size + spapr->hotplug_memory.base;; + uint64_t addr = i * lmb_size; uint32_t *dynamic_memory = cur_index; - drc = spapr_dr_connector_by_id(SPAPR_DR_CONNECTOR_TYPE_LMB, - addr/lmb_size); - g_assert(drc); - drck = SPAPR_DR_CONNECTOR_GET_CLASS(drc); - - dynamic_memory[0] = cpu_to_be32(addr >> 32); - dynamic_memory[1] = cpu_to_be32(addr & 0xffffffff); - dynamic_memory[2] = cpu_to_be32(drck->get_index(drc)); - dynamic_memory[3] = cpu_to_be32(0); /* reserved */ - dynamic_memory[4] = cpu_to_be32(numa_get_node(addr, NULL)); - if (addr < machine->ram_size || - memory_region_present(get_system_memory(), addr)) { - dynamic_memory[5] = cpu_to_be32(SPAPR_LMB_FLAGS_ASSIGNED); + if (i >= hotplug_lmb_start) { + sPAPRDRConnector *drc; + sPAPRDRConnectorClass *drck; + + drc = spapr_dr_connector_by_id(SPAPR_DR_CONNECTOR_TYPE_LMB, i); + g_assert(drc); + drck = SPAPR_DR_CONNECTOR_GET_CLASS(drc); + + dynamic_memory[0] = cpu_to_be32(addr >> 32); + dynamic_memory[1] = cpu_to_be32(addr & 0xffffffff); + dynamic_memory[2] = cpu_to_be32(drck->get_index(drc)); + dynamic_memory[3] = cpu_to_be32(0); /* reserved */ + dynamic_memory[4] = cpu_to_be32(numa_get_node(addr, NULL)); + if (memory_region_present(get_system_memory(), addr)) { + dynamic_memory[5] = cpu_to_be32(SPAPR_LMB_FLAGS_ASSIGNED); + } else { + dynamic_memory[5] = cpu_to_be32(0); + } } else { - dynamic_memory[5] = cpu_to_be32(0); + /* + * LMB information for RMA, boot time RAM and gap b/n RAM and + * hotplug memory region -- all these are marked as reserved + * and as having no valid DRC. + */ + dynamic_memory[0] = cpu_to_be32(addr >> 32); + dynamic_memory[1] = cpu_to_be32(addr & 0xffffffff); + dynamic_memory[2] = cpu_to_be32(0); + dynamic_memory[3] = cpu_to_be32(0); /* reserved */ + dynamic_memory[4] = cpu_to_be32(-1); + dynamic_memory[5] = cpu_to_be32(SPAPR_LMB_FLAGS_RESERVED | + SPAPR_LMB_FLAGS_DRC_INVALID); } cur_index += SPAPR_DR_LMB_LIST_ENTRY_SIZE; diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h index 971df3d..3ac85c0 100644 --- a/include/hw/ppc/spapr.h +++ b/include/hw/ppc/spapr.h @@ -620,9 +620,11 @@ int spapr_rng_populate_dt(void *fdt); #define SPAPR_DR_LMB_LIST_ENTRY_SIZE 6 /* - * This flag value defines the LMB as assigned in ibm,dynamic-memory - * property under ibm,dynamic-reconfiguration-memory node. + * Defines for flag value in ibm,dynamic-memory property under + * ibm,dynamic-reconfiguration-memory node. */ #define SPAPR_LMB_FLAGS_ASSIGNED 0x00000008 +#define SPAPR_LMB_FLAGS_DRC_INVALID 0x00000020 +#define SPAPR_LMB_FLAGS_RESERVED 0x00000080 #endif /* !defined (__HW_SPAPR_H__) */
Memory hotplug can fail for some combinations of RAM and maxmem when DDW is enabled in the presence of devices like nec-usb-xhci. DDW depends on maximum addressable memory returned by guest and this value is currently being calculated wrongly by the guest kernel routine memory_hotplug_max(). While there is an attempt to fix the guest kernel, this patch works around the problem within QEMU itself. memory_hotplug_max() routine in the guest kernel arrives at max addressable memory by multiplying lmb-size with the lmb-count obtained from ibm,dynamic-memory property. There are two assumptions here: - All LMBs are part of ibm,dynamic memory: This is not true for PowerKVM where only hot-pluggable LMBs are present in this property. - The memory area comprising of RAM and hotplug region is contiguous: This needn't be true always for PowerKVM as there can be gap between boot time RAM and hotplug region. To work around this guest kernel bug, ensure that ibm,dynamic-memory has information about all the LMBs (RMA, boot-time LMBs, future hotpluggable LMBs, and dummy LMBs to cover the gap between RAM and hotpluggable region). RMA is represented separately by memory@0 node. Hence mark RMA LMBs and also the LMBs for the gap b/n RAM and hotpluggable region as reserved and as having no valid DRC so that these LMBs are not considered by the guest. Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com> --- Changes in v4: - Included address information for all LMBs in ibm,dynamic-memory. - Use both RESERVED and DRC_INVALID flag bits for non-hotpluggable LMBs. v3: https://lists.gnu.org/archive/html/qemu-ppc/2016-06/msg00187.html hw/ppc/spapr.c | 57 ++++++++++++++++++++++++++++++++------------------ include/hw/ppc/spapr.h | 6 ++++-- 2 files changed, 41 insertions(+), 22 deletions(-)