| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <ed4ebc67-dc98-4ce4-af5e-b2f371d27c5b@linux.microsoft.com>
Date: Fri, 5 Sep 2025 12:50:33 -0700
From: Easwar Hariharan <easwar.hariharan@...ux.microsoft.com>
To: Nuno Das Neves <nunodasneves@...ux.microsoft.com>
Cc: linux-hyperv@...r.kernel.org, linux-kernel@...r.kernel.org,
easwar.hariharan@...ux.microsoft.com, kys@...rosoft.com,
haiyangz@...rosoft.com, wei.liu@...nel.org, mhklinux@...look.com,
decui@...rosoft.com, paekkaladevi@...ux.microsoft.com,
Jinank Jain <jinankjain@...ux.microsoft.com>
Subject: Re: [PATCH 6/6] mshv: Introduce new hypercall to map stats page for
L1VH partitions
On 8/28/2025 5:43 PM, Nuno Das Neves wrote:
> From: Jinank Jain <jinankjain@...ux.microsoft.com>
>
> Introduce HVCALL_MAP_STATS_PAGE2 which provides a map location (GPFN)
> to map the stats to. This hypercall is required for L1VH partitions,
> depending on the hypervisor version. This uses the same check as the
> state page map location; mshv_use_overlay_gpfn().
>
> Add mshv_map_vp_state_page() helpers to use this new hypercall or the
> old one depending on availability.
>
> For unmapping, the original HVCALL_UNMAP_STATS_PAGE works for both
> cases.
>
> Signed-off-by: Jinank Jain <jinankjain@...ux.microsoft.com>
> Signed-off-by: Nuno Das Neves <nunodasneves@...ux.microsoft.com>
> ---
> drivers/hv/mshv_root.h | 10 ++--
> drivers/hv/mshv_root_hv_call.c | 92 ++++++++++++++++++++++++++++++++--
> drivers/hv/mshv_root_main.c | 25 +++++----
> include/hyperv/hvgdk_mini.h | 1 +
> include/hyperv/hvhdk_mini.h | 7 +++
> 5 files changed, 115 insertions(+), 20 deletions(-)
>
> diff --git a/drivers/hv/mshv_root.h b/drivers/hv/mshv_root.h
> index d7c9520ef788..d16a020ae0ee 100644
> --- a/drivers/hv/mshv_root.h
> +++ b/drivers/hv/mshv_root.h
> @@ -297,11 +297,11 @@ int hv_call_connect_port(u64 port_partition_id, union hv_port_id port_id,
> int hv_call_disconnect_port(u64 connection_partition_id,
> union hv_connection_id connection_id);
> int hv_call_notify_port_ring_empty(u32 sint_index);
> -int hv_call_map_stat_page(enum hv_stats_object_type type,
> - const union hv_stats_object_identity *identity,
> - void **addr);
> -int hv_call_unmap_stat_page(enum hv_stats_object_type type,
> - const union hv_stats_object_identity *identity);
> +int hv_map_stats_page(enum hv_stats_object_type type,
> + const union hv_stats_object_identity *identity,
> + void **addr);
> +int hv_unmap_stats_page(enum hv_stats_object_type type, void *page_addr,
> + const union hv_stats_object_identity *identity);
> int hv_call_modify_spa_host_access(u64 partition_id, struct page **pages,
> u64 page_struct_count, u32 host_access,
> u32 flags, u8 acquire);
> diff --git a/drivers/hv/mshv_root_hv_call.c b/drivers/hv/mshv_root_hv_call.c
> index 1882cc90f2f5..44013751cfc1 100644
> --- a/drivers/hv/mshv_root_hv_call.c
> +++ b/drivers/hv/mshv_root_hv_call.c
> @@ -804,6 +804,45 @@ hv_call_notify_port_ring_empty(u32 sint_index)
> return hv_result_to_errno(status);
> }
>
> +static int
> +hv_call_map_stats_page2(enum hv_stats_object_type type,
Again, one line please. Also below.
> + const union hv_stats_object_identity *identity,
> + u64 map_location)
> +{
> + unsigned long flags;
> + struct hv_input_map_stats_page2 *input;
> + u64 status;
> + int ret;
> +
> + if (!map_location || !mshv_use_overlay_gpfn())
> + return -EINVAL;
> +
> + do {
> + local_irq_save(flags);
> + input = *this_cpu_ptr(hyperv_pcpu_input_arg);
> +
> + memset(input, 0, sizeof(*input));
> + input->type = type;
> + input->identity = *identity;
> + input->map_location = map_location;
> +
> + status = hv_do_hypercall(HVCALL_MAP_STATS_PAGE2, input, NULL);
> +
> + local_irq_restore(flags);
> + if (hv_result(status) != HV_STATUS_INSUFFICIENT_MEMORY) {
> + if (hv_result_success(status))
> + break;
> + hv_status_debug(status, "\n");
> + return hv_result_to_errno(status);
> + }
> +
> + ret = hv_call_deposit_pages(NUMA_NO_NODE,
> + hv_current_partition_id, 1);
> + } while (!ret);
> +
> + return ret;
> +}
> +
> static int
> hv_stats_get_area_type(enum hv_stats_object_type type,
> const union hv_stats_object_identity *identity)
> @@ -822,9 +861,10 @@ hv_stats_get_area_type(enum hv_stats_object_type type,
> return -EINVAL;
> }
>
> -int hv_call_map_stat_page(enum hv_stats_object_type type,
> - const union hv_stats_object_identity *identity,
> - void **addr)
> +static int
> +hv_call_map_stats_page(enum hv_stats_object_type type,
> + const union hv_stats_object_identity *identity,
> + void **addr)
...
> {
> unsigned long flags;
> struct hv_input_map_stats_page *input;
> @@ -880,8 +920,37 @@ int hv_call_map_stat_page(enum hv_stats_object_type type,
> return ret;
> }
>
> -int hv_call_unmap_stat_page(enum hv_stats_object_type type,
> - const union hv_stats_object_identity *identity)
> +int hv_map_stats_page(enum hv_stats_object_type type,
> + const union hv_stats_object_identity *identity,
> + void **addr)
> +{
> + int ret;
> + struct page *allocated_page = NULL;
> +
> + if (!addr)
> + return -EINVAL;
> +
> + if (mshv_use_overlay_gpfn()) {
> + allocated_page = alloc_page(GFP_KERNEL);
> + if (!allocated_page)
> + return -ENOMEM;
> +
> + ret = hv_call_map_stats_page2(type, identity,
> + page_to_pfn(allocated_page));
> + *addr = page_address(allocated_page);
> + } else {
> + ret = hv_call_map_stats_page(type, identity, addr);
> + }
> +
> + if (ret && allocated_page)
> + __free_page(allocated_page);
> +
> + return ret;
> +}
> +
> +static int
> +hv_call_unmap_stats_page(enum hv_stats_object_type type,
...
> + const union hv_stats_object_identity *identity)
> {
> unsigned long flags;
> struct hv_input_unmap_stats_page *input;
> @@ -900,6 +969,19 @@ int hv_call_unmap_stat_page(enum hv_stats_object_type type,
> return hv_result_to_errno(status);
> }
>
> +int hv_unmap_stats_page(enum hv_stats_object_type type, void *page_addr,
> + const union hv_stats_object_identity *identity)
> +{
> + int ret;
> +
> + ret = hv_call_unmap_stats_page(type, identity);
> +
> + if (mshv_use_overlay_gpfn() && page_addr)
> + __free_page(virt_to_page(page_addr));
> +
> + return ret;
> +}
> +
> int hv_call_modify_spa_host_access(u64 partition_id, struct page **pages,
> u64 page_struct_count, u32 host_access,
> u32 flags, u8 acquire)
> diff --git a/drivers/hv/mshv_root_main.c b/drivers/hv/mshv_root_main.c
> index f91880cc9e29..1699423cc524 100644
> --- a/drivers/hv/mshv_root_main.c
> +++ b/drivers/hv/mshv_root_main.c
> @@ -894,7 +894,8 @@ mshv_vp_release(struct inode *inode, struct file *filp)
> return 0;
> }
>
> -static void mshv_vp_stats_unmap(u64 partition_id, u32 vp_index)
> +static void mshv_vp_stats_unmap(u64 partition_id, u32 vp_index,
> + void *stats_pages[])
> {
> union hv_stats_object_identity identity = {
> .vp.partition_id = partition_id,
> @@ -902,10 +903,13 @@ static void mshv_vp_stats_unmap(u64 partition_id, u32 vp_index)
> };
>
> identity.vp.stats_area_type = HV_STATS_AREA_SELF;
> - hv_call_unmap_stat_page(HV_STATS_OBJECT_VP, &identity);
> + hv_unmap_stats_page(HV_STATS_OBJECT_VP, NULL, &identity);
> +
> + if (stats_pages[HV_STATS_AREA_PARENT] == stats_pages[HV_STATS_AREA_SELF])
> + return;
>
> identity.vp.stats_area_type = HV_STATS_AREA_PARENT;
> - hv_call_unmap_stat_page(HV_STATS_OBJECT_VP, &identity);
> + hv_unmap_stats_page(HV_STATS_OBJECT_VP, NULL, &identity);
> }
>
> static int mshv_vp_stats_map(u64 partition_id, u32 vp_index,
> @@ -918,14 +922,14 @@ static int mshv_vp_stats_map(u64 partition_id, u32 vp_index,
> int err;
>
> identity.vp.stats_area_type = HV_STATS_AREA_SELF;
> - err = hv_call_map_stat_page(HV_STATS_OBJECT_VP, &identity,
> - &stats_pages[HV_STATS_AREA_SELF]);
> + err = hv_map_stats_page(HV_STATS_OBJECT_VP, &identity,
> + &stats_pages[HV_STATS_AREA_SELF]);
Shouldn't this be in the previous patch where the other hv_call_map_stat_page() calls were
converted, same below?
> if (err)
> return err;
>
> identity.vp.stats_area_type = HV_STATS_AREA_PARENT;
> - err = hv_call_map_stat_page(HV_STATS_OBJECT_VP, &identity,
> - &stats_pages[HV_STATS_AREA_PARENT]);
> + err = hv_map_stats_page(HV_STATS_OBJECT_VP, &identity,
> + &stats_pages[HV_STATS_AREA_PARENT]);
...
> if (err)
> goto unmap_self;
>
> @@ -936,7 +940,7 @@ static int mshv_vp_stats_map(u64 partition_id, u32 vp_index,
>
> unmap_self:
> identity.vp.stats_area_type = HV_STATS_AREA_SELF;
> - hv_call_unmap_stat_page(HV_STATS_OBJECT_VP, &identity);
> + hv_unmap_stats_page(HV_STATS_OBJECT_VP, NULL, &identity);
> return err;
> }
>
<snip>
Powered by blists - more mailing lists