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From: Linu Cherian <linuc.decode@gmail.com>
To: Eric Auger <eric.auger@redhat.com>
Cc: eric.auger.pro@gmail.com, peter.maydell@linaro.org,
	qemu-arm@nongnu.org, qemu-devel@nongnu.org,
	alex.williamson@redhat.com, prem.mallappa@gmail.com,
	mohun106@gmail.com, drjones@redhat.com, tcain@qti.qualcomm.com,
	Radha.Chintakuntla@cavium.com, Sunil.Goutham@cavium.com,
	mst@redhat.com, jean-philippe.brucker@arm.com, tn@semihalf.com,
	will.deacon@arm.com, robin.murphy@arm.com, peterx@redhat.com,
	bharat.bhushan@nxp.com, christoffer.dall@linaro.org
Subject: Re: [Qemu-devel] [Qemu-arm] [RFC v6 8/9] hw/arm/smmuv3: VFIO integration
Date: Mon, 21 Aug 2017 06:51:13 +0530	[thread overview]
Message-ID: <20170821012113.GA12220@virtx40> (raw)
In-Reply-To: <1502461354-11327-9-git-send-email-eric.auger@redhat.com>

Hi Eric,


On Fri Aug 11, 2017 at 04:22:33PM +0200, Eric Auger wrote:
> This patch allows doing PCIe passthrough with a guest exposed
> with a vSMMUv3. It implements the replay and notify_flag_changed
> iommu ops. Also on TLB and data structure invalidation commands,
> we replay the mappings so that the physical IOMMU implements
> updated stage 1 settings (Guest IOVA -> Guest PA) + stage 2 settings.
> 
> This works only if the guest smmuv3 driver implements the
> "tlbi-on-map" option.
> 
> Signed-off-by: Eric Auger <eric.auger@redhat.com>
>

Appreciate if you could point to some documentation that explains 
the attach, detach, map,unmap flows for a passthrough device 
with emulated IOMMU. 
Thanks. 
> ---
> 
> v5 -> v6:
> - use IOMMUMemoryRegion
> - handle implementation defined SMMU_CMD_TLBI_NH_VA_AM cmd
>   (goes along with TLBI_ON_MAP FW quirk)
> - replay systematically unmap the whole range first
> - smmuv3_map_hook does not unmap anymore and the unmap is done
>   before the replay
> - add and use smmuv3_context_device_invalidate instead of
>   blindly replaying everything
> ---
>  hw/arm/smmuv3-internal.h |   1 +
>  hw/arm/smmuv3.c          | 265 ++++++++++++++++++++++++++++++++++++++++++++++-
>  hw/arm/trace-events      |  14 +++
>  3 files changed, 277 insertions(+), 3 deletions(-)
> 
> diff --git a/hw/arm/smmuv3-internal.h b/hw/arm/smmuv3-internal.h
> index e255df1..ac4628f 100644
> --- a/hw/arm/smmuv3-internal.h
> +++ b/hw/arm/smmuv3-internal.h
> @@ -344,6 +344,7 @@ enum {
>      SMMU_CMD_RESUME          = 0x44,
>      SMMU_CMD_STALL_TERM,
>      SMMU_CMD_SYNC,          /* 0x46 */
> +    SMMU_CMD_TLBI_NH_VA_AM   = 0x8F, /* VIOMMU Impl Defined */
>  };
>  
>  static const char *cmd_stringify[] = {
> diff --git a/hw/arm/smmuv3.c b/hw/arm/smmuv3.c
> index e195a0e..89fb116 100644
> --- a/hw/arm/smmuv3.c
> +++ b/hw/arm/smmuv3.c
> @@ -25,6 +25,7 @@
>  #include "exec/address-spaces.h"
>  #include "trace.h"
>  #include "qemu/error-report.h"
> +#include "exec/target_page.h"
>  
>  #include "hw/arm/smmuv3.h"
>  #include "smmuv3-internal.h"
> @@ -143,6 +144,71 @@ static MemTxResult smmu_read_cmdq(SMMUV3State *s, Cmd *cmd)
>      return ret;
>  }
>  
> +static void smmuv3_replay_all(SMMUState *s)
> +{
> +    SMMUNotifierNode *node;
> +
> +    QLIST_FOREACH(node, &s->notifiers_list, next) {
> +        trace_smmuv3_replay_all(node->sdev->iommu.parent_obj.name);
> +        memory_region_iommu_replay_all(&node->sdev->iommu);
> +    }
> +}
> +
> +/* Replay the mappings for a given streamid */
> +static void smmuv3_context_device_invalidate(SMMUState *s, uint16_t sid)
> +{
> +    uint8_t bus_n, devfn;
> +    SMMUPciBus *smmu_bus;
> +    SMMUDevice *smmu;
> +
> +    trace_smmuv3_context_device_invalidate(sid);
> +    bus_n = PCI_BUS_NUM(sid);
> +    smmu_bus = smmu_find_as_from_bus_num(s, bus_n);
> +    if (smmu_bus) {
> +        devfn = PCI_FUNC(sid);
> +        smmu = smmu_bus->pbdev[devfn];
> +        if (smmu) {
> +            memory_region_iommu_replay_all(&smmu->iommu);
> +        }
> +    }
> +}
> +
> +static void smmuv3_replay_single(IOMMUMemoryRegion *mr, IOMMUNotifier *n,
> +                                 uint64_t iova);
> +
> +static void smmuv3_replay_range(IOMMUMemoryRegion *mr, IOMMUNotifier *n,
> +                                 uint64_t iova, size_t nb_pages);
> +
> +static void smmuv3_notify_single(SMMUState *s, uint64_t iova)
> +{
> +    SMMUNotifierNode *node;
> +
> +    QLIST_FOREACH(node, &s->notifiers_list, next) {
> +        IOMMUMemoryRegion *mr = &node->sdev->iommu;
> +        IOMMUNotifier *n;
> +
> +        trace_smmuv3_notify_all(node->sdev->iommu.parent_obj.name, iova);
> +        IOMMU_NOTIFIER_FOREACH(n, mr) {
> +            smmuv3_replay_single(mr, n, iova);
> +        }
> +    }
> +}
> +
> +static void smmuv3_notify_range(SMMUState *s, uint64_t iova, size_t size)
> +{
> +    SMMUNotifierNode *node;
> +
> +    QLIST_FOREACH(node, &s->notifiers_list, next) {
> +        IOMMUMemoryRegion *mr = &node->sdev->iommu;
> +        IOMMUNotifier *n;
> +
> +        trace_smmuv3_notify_all(node->sdev->iommu.parent_obj.name, iova);
> +        IOMMU_NOTIFIER_FOREACH(n, mr) {
> +            smmuv3_replay_range(mr, n, iova, size);
> +        }
> +    }
> +}
> +
>  static int smmu_cmdq_consume(SMMUV3State *s)
>  {
>      uint32_t error = SMMU_CMD_ERR_NONE;
> @@ -178,28 +244,38 @@ static int smmu_cmdq_consume(SMMUV3State *s)
>              break;
>          case SMMU_CMD_PREFETCH_CONFIG:
>          case SMMU_CMD_PREFETCH_ADDR:
> +            break;
>          case SMMU_CMD_CFGI_STE:
>          {
>               uint32_t streamid = cmd.word[1];
>  
>               trace_smmuv3_cmdq_cfgi_ste(streamid);
> -            break;
> +             smmuv3_context_device_invalidate(&s->smmu_state, streamid);
> +             break;
>          }
>          case SMMU_CMD_CFGI_STE_RANGE: /* same as SMMU_CMD_CFGI_ALL */
>          {
> -            uint32_t start = cmd.word[1], range, end;
> +            uint32_t start = cmd.word[1], range, end, i;
>  
>              range = extract32(cmd.word[2], 0, 5);
>              end = start + (1 << (range + 1)) - 1;
>              trace_smmuv3_cmdq_cfgi_ste_range(start, end);
> +            for (i = start; i <= end; i++) {
> +                smmuv3_context_device_invalidate(&s->smmu_state, i);
> +            }
>              break;
>          }
>          case SMMU_CMD_CFGI_CD:
>          case SMMU_CMD_CFGI_CD_ALL:
> +        {
> +             uint32_t streamid = cmd.word[1];
> +
> +            smmuv3_context_device_invalidate(&s->smmu_state, streamid);
>              break;
> +        }
>          case SMMU_CMD_TLBI_NH_ALL:
>          case SMMU_CMD_TLBI_NH_ASID:
> -            printf("%s TLBI* replay\n", __func__);
> +            smmuv3_replay_all(&s->smmu_state);
>              break;
>          case SMMU_CMD_TLBI_NH_VA:
>          {
> @@ -210,6 +286,20 @@ static int smmu_cmdq_consume(SMMUV3State *s)
>              uint64_t addr = high << 32 | (low << 12);
>  
>              trace_smmuv3_cmdq_tlbi_nh_va(asid, vmid, addr);
> +            smmuv3_notify_single(&s->smmu_state, addr);
> +            break;
> +        }
> +        case SMMU_CMD_TLBI_NH_VA_AM:
> +        {
> +            int asid = extract32(cmd.word[1], 16, 16);
> +            int am = extract32(cmd.word[1], 0, 16);
> +            uint64_t low = extract32(cmd.word[2], 12, 20);
> +            uint64_t high = cmd.word[3];
> +            uint64_t addr = high << 32 | (low << 12);
> +            size_t size = am << 12;
> +
> +            trace_smmuv3_cmdq_tlbi_nh_va_am(asid, am, addr, size);
> +            smmuv3_notify_range(&s->smmu_state, addr, size);
>              break;
>          }
>          case SMMU_CMD_TLBI_NH_VAA:
> @@ -222,6 +312,7 @@ static int smmu_cmdq_consume(SMMUV3State *s)
>          case SMMU_CMD_TLBI_S12_VMALL:
>          case SMMU_CMD_TLBI_S2_IPA:
>          case SMMU_CMD_TLBI_NSNH_ALL:
> +            smmuv3_replay_all(&s->smmu_state);
>              break;
>          case SMMU_CMD_ATC_INV:
>          case SMMU_CMD_PRI_RESP:
> @@ -804,6 +895,172 @@ out:
>      return entry;
>  }
>  
> +static int smmuv3_replay_hook(IOMMUTLBEntry *entry, void *private)
> +{
> +    trace_smmuv3_replay_hook(entry->iova, entry->translated_addr,
> +                             entry->addr_mask, entry->perm);
> +    memory_region_notify_one((IOMMUNotifier *)private, entry);
> +    return 0;
> +}
> +
> +static int smmuv3_map_hook(IOMMUTLBEntry *entry, void *private)
> +{
> +    trace_smmuv3_map_hook(entry->iova, entry->translated_addr,
> +                          entry->addr_mask, entry->perm);
> +    memory_region_notify_one((IOMMUNotifier *)private, entry);
> +    return 0;
> +}
> +
> +/* Unmap the whole range in the notifier's scope. */
> +static void smmuv3_unmap_notifier(SMMUDevice *sdev, IOMMUNotifier *n)
> +{
> +    IOMMUTLBEntry entry;
> +    hwaddr size;
> +    hwaddr start = n->start;
> +    hwaddr end = n->end;
> +
> +    size = end - start + 1;
> +
> +    entry.target_as = &address_space_memory;
> +    /* Adjust iova for the size */
> +    entry.iova = n->start & ~(size - 1);
> +    /* This field is meaningless for unmap */
> +    entry.translated_addr = 0;
> +    entry.perm = IOMMU_NONE;
> +    entry.addr_mask = size - 1;
> +
> +    /* TODO: check start/end/size/mask */
> +
> +    trace_smmuv3_unmap_notifier(pci_bus_num(sdev->bus),
> +                                PCI_SLOT(sdev->devfn),
> +                                PCI_FUNC(sdev->devfn),
> +                                entry.iova, size);
> +
> +    memory_region_notify_one(n, &entry);
> +}
> +
> +static void smmuv3_replay(IOMMUMemoryRegion *mr, IOMMUNotifier *n)
> +{
> +    SMMUDevice *sdev = container_of(mr, SMMUDevice, iommu);
> +    SMMUV3State *s = sdev->smmu;
> +    SMMUBaseClass *sbc = SMMU_DEVICE_GET_CLASS(s);
> +    SMMUTransCfg cfg = {};
> +    int ret;
> +
> +    smmuv3_unmap_notifier(sdev, n);
> +
> +    ret = smmuv3_decode_config(mr, &cfg);
> +    if (ret) {
> +        error_report("%s error decoding the configuration for iommu mr=%s",
> +                     __func__, mr->parent_obj.name);
> +    }
> +
> +    if (cfg.disabled || cfg.bypassed) {
> +        return;
> +    }
> +    /* is the smmu enabled */
> +    sbc->page_walk_64(&cfg, 0, (1ULL << (64 - cfg.tsz)) - 1, false,
> +                      smmuv3_replay_hook, n);
> +}
> +static void smmuv3_replay_range(IOMMUMemoryRegion *mr, IOMMUNotifier *n,
> +                                 uint64_t iova, size_t size)
> +{
> +    SMMUDevice *sdev = container_of(mr, SMMUDevice, iommu);
> +    SMMUV3State *s = sdev->smmu;
> +    SMMUBaseClass *sbc = SMMU_DEVICE_GET_CLASS(s);
> +    SMMUTransCfg cfg = {};
> +    IOMMUTLBEntry entry;
> +    int ret;
> +
> +    trace_smmuv3_replay_range(mr->parent_obj.name, iova, size, n);
> +    ret = smmuv3_decode_config(mr, &cfg);
> +    if (ret) {
> +        error_report("%s error decoding the configuration for iommu mr=%s",
> +                     __func__, mr->parent_obj.name);
> +    }
> +
> +    if (cfg.disabled || cfg.bypassed) {
> +        return;
> +    }
> +
> +    /* first unmap */
> +    entry.target_as = &address_space_memory;
> +    entry.iova = iova & ~(size - 1);
> +    entry.addr_mask = size - 1;
> +    entry.perm = IOMMU_NONE;
> +
> +    memory_region_notify_one(n, &entry);
> +
> +    /* then figure out if a new mapping needs to be applied */
> +    sbc->page_walk_64(&cfg, iova, iova + entry.addr_mask , false,
> +                      smmuv3_map_hook, n);
> +}
> +
> +static void smmuv3_replay_single(IOMMUMemoryRegion *mr, IOMMUNotifier *n,
> +                                 uint64_t iova)
> +{
> +    SMMUDevice *sdev = container_of(mr, SMMUDevice, iommu);
> +    SMMUV3State *s = sdev->smmu;
> +    size_t target_page_size = qemu_target_page_size();
> +    SMMUBaseClass *sbc = SMMU_DEVICE_GET_CLASS(s);
> +    SMMUTransCfg cfg = {};
> +    IOMMUTLBEntry entry;
> +    int ret;
> +
> +    trace_smmuv3_replay_single(mr->parent_obj.name, iova, n);
> +    ret = smmuv3_decode_config(mr, &cfg);
> +    if (ret) {
> +        error_report("%s error decoding the configuration for iommu mr=%s",
> +                     __func__, mr->parent_obj.name);
> +    }
> +
> +    if (cfg.disabled || cfg.bypassed) {
> +        return;
> +    }
> +
> +    /* first unmap */
> +    entry.target_as = &address_space_memory;
> +    entry.iova = iova & ~(target_page_size - 1);
> +    entry.addr_mask = target_page_size - 1;
> +    entry.perm = IOMMU_NONE;
> +
> +    memory_region_notify_one(n, &entry);
> +
> +    /* then figure out if a new mapping needs to be applied */
> +    sbc->page_walk_64(&cfg, iova, iova + 1, false,
> +                      smmuv3_map_hook, n);
> +}
> +
> +static void smmuv3_notify_flag_changed(IOMMUMemoryRegion *iommu,
> +                                       IOMMUNotifierFlag old,
> +                                       IOMMUNotifierFlag new)
> +{
> +    SMMUDevice *sdev = container_of(iommu, SMMUDevice, iommu);
> +    SMMUV3State *s3 = sdev->smmu;
> +    SMMUState *s = &(s3->smmu_state);
> +    SMMUNotifierNode *node = NULL;
> +    SMMUNotifierNode *next_node = NULL;
> +
> +    if (old == IOMMU_NOTIFIER_NONE) {
> +        trace_smmuv3_notify_flag_add(iommu->parent_obj.name);
> +        node = g_malloc0(sizeof(*node));
> +        node->sdev = sdev;
> +        QLIST_INSERT_HEAD(&s->notifiers_list, node, next);
> +        return;
> +    }
> +
> +    /* update notifier node with new flags */
> +    QLIST_FOREACH_SAFE(node, &s->notifiers_list, next, next_node) {
> +        if (node->sdev == sdev) {
> +            if (new == IOMMU_NOTIFIER_NONE) {
> +                trace_smmuv3_notify_flag_del(iommu->parent_obj.name);
> +                QLIST_REMOVE(node, next);
> +                g_free(node);
> +            }
> +            return;
> +        }
> +    }
> +}
>  
>  static inline void smmu_update_base_reg(SMMUV3State *s, uint64_t *base,
>                                          uint64_t val)
> @@ -1125,6 +1382,8 @@ static void smmuv3_iommu_memory_region_class_init(ObjectClass *klass,
>      IOMMUMemoryRegionClass *imrc = IOMMU_MEMORY_REGION_CLASS(klass);
>  
>      imrc->translate = smmuv3_translate;
> +    imrc->notify_flag_changed = smmuv3_notify_flag_changed;
> +    imrc->replay = smmuv3_replay;
>  }
>  
>  static const TypeInfo smmuv3_type_info = {
> diff --git a/hw/arm/trace-events b/hw/arm/trace-events
> index f9b9cbe..8228e26 100644
> --- a/hw/arm/trace-events
> +++ b/hw/arm/trace-events
> @@ -27,6 +27,7 @@ smmuv3_cmdq_opcode(const char *opcode) "<--- %s"
>  smmuv3_cmdq_cfgi_ste(int streamid) "     |_ streamid =%d"
>  smmuv3_cmdq_cfgi_ste_range(int start, int end) "     |_ start=0x%d - end=0x%d"
>  smmuv3_cmdq_tlbi_nh_va(int asid, int vmid, uint64_t addr) "     |_ asid =%d vmid =%d addr=0x%"PRIx64
> +smmuv3_cmdq_tlbi_nh_va_am(int asid, int am, size_t size, uint64_t addr) "     |_ asid =%d am =%d size=0x%lx addr=0x%"PRIx64
>  smmuv3_cmdq_consume_sev(void) "CMD_SYNC CS=SEV not supported, ignoring"
>  smmuv3_cmdq_consume_out(uint8_t prod_wrap, uint32_t prod, uint8_t cons_wrap, uint32_t cons) "prod_wrap:%d, prod:0x%x cons_wrap:%d cons:0x%x"
>  smmuv3_update(bool is_empty, uint32_t prod, uint32_t cons, uint8_t prod_wrap, uint8_t cons_wrap) "q empty:%d prod:%d cons:%d p.wrap:%d p.cons:%d"
> @@ -50,3 +51,16 @@ smmuv3_dump_ste(int i, uint32_t word0, int j,  uint32_t word1) "STE[%2d]: 0x%x\t
>  smmuv3_dump_cd(int i, uint32_t word0, int j,  uint32_t word1) "CD[%2d]: 0x%x\t CD[%2d]: 0x%x"
>  smmuv3_dump_cmd(int i, uint32_t word0, int j,  uint32_t word1) "CMD[%2d]: 0x%x\t CMD[%2d]: 0x%x"
>  smmuv3_cfg_stage(int s, uint32_t oas, uint32_t tsz, uint64_t ttbr, bool aa64, uint32_t granule_sz, int initial_level) "TransCFG stage:%d oas:%d tsz:%d ttbr:0x%"PRIx64"  aa64:%d granule_sz:%d, initial_level = %d"
> +
> +smmuv3_replay(uint16_t sid, bool enabled) "sid=%d, enabled=%d"
> +smmuv3_replay_hook(hwaddr iova, hwaddr pa, hwaddr mask, int perm) "iova=0x%"PRIx64" pa=0x%" PRIx64" mask=0x%"PRIx64" perm=%d"
> +smmuv3_map_hook(hwaddr iova, hwaddr pa, hwaddr mask, int perm) "iova=0x%"PRIx64" pa=0x%" PRIx64" mask=0x%"PRIx64" perm=%d"
> +smmuv3_notify_flag_add(const char *iommu) "ADD SMMUNotifier node for iommu mr=%s"
> +smmuv3_notify_flag_del(const char *iommu) "DEL SMMUNotifier node for iommu mr=%s"
> +smmuv3_replay_single(const char *name, uint64_t iova, void *n) "iommu mr=%s iova=0x%"PRIx64" n=%p"
> +smmuv3_replay_range(const char *name, uint64_t iova, size_t size, void *n) "iommu mr=%s iova=0x%"PRIx64" size=0x%lx n=%p"
> +smmuv3_replay_all(const char *name) "iommu mr=%s"
> +smmuv3_notify_all(const char *name, uint64_t iova) "iommu mr=%s iova=0x%"PRIx64
> +smmuv3_unmap_notifier(uint8_t bus, uint8_t slot, uint8_t fn, uint64_t iova, uint64_t size) "Device %02x:%02x.%x start 0x%"PRIx64" size 0x%"PRIx64
> +smmuv3_context_device_invalidate(uint32_t sid) "sid=%d"
> +
> -- 
> 2.5.5
> 
> 

-- 
Linu cherian

  reply	other threads:[~2017-08-21  1:21 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-08-11 14:22 [Qemu-devel] [RFC v6 0/9] ARM SMMUv3 Emulation Support Eric Auger
2017-08-11 14:22 ` [Qemu-devel] [RFC v6 1/9] hw/arm/smmu-common: smmu base class Eric Auger
2017-08-11 14:22 ` [Qemu-devel] [RFC v6 2/9] hw/arm/smmuv3: smmuv3 emulation model Eric Auger
2017-08-11 14:22 ` [Qemu-devel] [RFC v6 3/9] hw/arm/virt: Add SMMUv3 to the virt board Eric Auger
2017-08-11 14:22 ` [Qemu-devel] [RFC v6 4/9] hw/arm/virt: Add 2.11 machine type Eric Auger
2017-08-11 14:22 ` [Qemu-devel] [RFC v6 5/9] hw/arm/virt-acpi-build: Add smmuv3 node in IORT table Eric Auger
2017-08-11 14:22 ` [Qemu-devel] [RFC v6 6/9] hw/arm/virt: Add tlbi-on-map property to the smmuv3 node Eric Auger
2017-08-11 14:22 ` [Qemu-devel] [RFC v6 7/9] target/arm/kvm: Translate the MSI doorbell in kvm_arch_fixup_msi_route Eric Auger
2017-08-11 14:22 ` [Qemu-devel] [RFC v6 8/9] hw/arm/smmuv3: VFIO integration Eric Auger
2017-08-21  1:21   ` Linu Cherian [this message]
2017-08-23  4:24   ` [Qemu-devel] [Qemu-arm] " Linu Cherian
2017-08-23  6:39     ` Auger Eric
2017-08-25 17:13       ` Michael S. Tsirkin
2017-08-11 14:22 ` [Qemu-devel] [RFC v6 9/9] hw/arm/virt-acpi-build: Use the ACPI_IORT_SMMU_V3_CACHING_MODE model Eric Auger
2017-08-11 15:38 ` [Qemu-devel] [RFC v6 0/9] ARM SMMUv3 Emulation Support no-reply

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