* Re: [PATCH v3 1/5] mshv: Only map vp->vp_stats_pages if on root scheduler
From: Stanislav Kinsburskii @ 2025-09-18 18:38 UTC (permalink / raw)
To: Nuno Das Neves
Cc: linux-hyperv, linux-kernel, prapal, easwar.hariharan, tiala,
anirudh, paekkaladevi, kys, haiyangz, wei.liu, decui
In-Reply-To: <1758066262-15477-2-git-send-email-nunodasneves@linux.microsoft.com>
On Tue, Sep 16, 2025 at 04:44:18PM -0700, Nuno Das Neves wrote:
> This mapping is only used for checking if the dispatch thread is
> blocked. This is only relevant for the root scheduler, so check the
> scheduler type to determine whether to map/unmap these pages, instead of
> the current check, which is incorrect.
>
> Signed-off-by: Nuno Das Neves <nunodasneves@linux.microsoft.com>
> Reviewed-by: Anirudh Rayabharam <anirudh@anirudhrb.com>
> Reviewed-by: Praveen K Paladugu <prapal@linux.microsoft.com>
> Reviewed-by: Easwar Hariharan <easwar.hariharan@linux.microsoft.com>
> Reviewed-by: Tianyu Lan <tiala@microsoft.com>
> ---
> drivers/hv/mshv_root_main.c | 12 ++++++++----
> 1 file changed, 8 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/hv/mshv_root_main.c b/drivers/hv/mshv_root_main.c
> index e3b2bd417c46..24df47726363 100644
> --- a/drivers/hv/mshv_root_main.c
> +++ b/drivers/hv/mshv_root_main.c
> @@ -934,7 +934,11 @@ mshv_partition_ioctl_create_vp(struct mshv_partition *partition,
> goto unmap_register_page;
> }
>
> - if (hv_parent_partition()) {
> + /*
> + * This mapping of the stats page is for detecting if dispatch thread
> + * is blocked - only relevant for root scheduler
> + */
> + if (hv_scheduler_type == HV_SCHEDULER_TYPE_ROOT) {
> ret = mshv_vp_stats_map(partition->pt_id, args.vp_index,
> stats_pages);
> if (ret)
> @@ -963,7 +967,7 @@ mshv_partition_ioctl_create_vp(struct mshv_partition *partition,
> if (mshv_partition_encrypted(partition) && is_ghcb_mapping_available())
> vp->vp_ghcb_page = page_to_virt(ghcb_page);
>
> - if (hv_parent_partition())
> + if (hv_scheduler_type == HV_SCHEDULER_TYPE_ROOT)
> memcpy(vp->vp_stats_pages, stats_pages, sizeof(stats_pages));
>
> /*
> @@ -986,7 +990,7 @@ mshv_partition_ioctl_create_vp(struct mshv_partition *partition,
> free_vp:
> kfree(vp);
> unmap_stats_pages:
> - if (hv_parent_partition())
> + if (hv_scheduler_type == HV_SCHEDULER_TYPE_ROOT)
> mshv_vp_stats_unmap(partition->pt_id, args.vp_index);
> unmap_ghcb_page:
> if (mshv_partition_encrypted(partition) && is_ghcb_mapping_available()) {
> @@ -1740,7 +1744,7 @@ static void destroy_partition(struct mshv_partition *partition)
> if (!vp)
> continue;
>
> - if (hv_parent_partition())
> + if (hv_scheduler_type == HV_SCHEDULER_TYPE_ROOT)
> mshv_vp_stats_unmap(partition->pt_id, vp->vp_index);
>
> if (vp->vp_register_page) {
Acked-by: Stanislav Kinsburskii <skinsburskii@linux.microsoft.com>
> --
> 2.34.1
>
^ permalink raw reply
* Re: [PATCH v1 5/6] x86/hyperv: Implement hypervisor ram collection into vmcore
From: Stanislav Kinsburskii @ 2025-09-18 17:11 UTC (permalink / raw)
To: Mukesh Rathor
Cc: linux-hyperv, linux-kernel, linux-arch, kys, haiyangz, wei.liu,
decui, tglx, mingo, bp, dave.hansen, x86, hpa, arnd
In-Reply-To: <20250910001009.2651481-6-mrathor@linux.microsoft.com>
On Tue, Sep 09, 2025 at 05:10:08PM -0700, Mukesh Rathor wrote:
<snip>
> +static noinline __noclone void crash_nmi_callback(struct pt_regs *regs)
> +{
> + struct hv_input_disable_hyp_ex *input;
> + u64 status;
> + int msecs = 1000, ccpu = smp_processor_id();
> +
> + if (ccpu == 0) {
> + /* crash_save_cpu() will be done in the kexec path */
> + cpu_emergency_stop_pt(); /* disable performance trace */
> + atomic_inc(&crash_cpus_wait);
> + } else {
> + crash_save_cpu(regs, ccpu);
> + cpu_emergency_stop_pt(); /* disable performance trace */
> + atomic_inc(&crash_cpus_wait);
> + for (;;); /* cause no vmexits */
> + }
> +
> + while (atomic_read(&crash_cpus_wait) < num_online_cpus() && msecs--)
> + mdelay(1);
> +
> + stop_nmi();
> + if (!hv_has_crashed)
> + hv_notify_prepare_hyp();
> +
> + if (crashing_cpu == -1)
> + crashing_cpu = ccpu; /* crash cmd uses this */
> +
> + hv_hvcrash_ctxt_save();
> + hv_mark_tss_not_busy();
> + hv_crash_fixup_kernpt();
> +
> + input = *this_cpu_ptr(hyperv_pcpu_input_arg);
> + memset(input, 0, sizeof(*input));
> + input->rip = trampoline_pa; /* PA of hv_crash_asm32 */
> + input->arg = devirt_cr3arg; /* PA of trampoline page table L4 */
> +
> + status = hv_do_hypercall(HVCALL_DISABLE_HYP_EX, input, NULL);
> +
> + /* Devirt failed, just reboot as things are in very bad state now */
> + native_wrmsrq(HV_X64_MSR_RESET, 1); /* get hv to reboot */
AFAIU here ...
> +}
> +
> +/*
> + * Generic nmi callback handler: could be called without any crash also.
> + * hv crash: hypervisor injects nmi's into all cpus
> + * lx crash: panicing cpu sends nmi to all but self via crash_stop_other_cpus
> + */
> +static int hv_crash_nmi_local(unsigned int cmd, struct pt_regs *regs)
> +{
> + int ccpu = smp_processor_id();
> +
> + if (!hv_has_crashed && hv_cda && hv_cda->cda_valid)
> + hv_has_crashed = 1;
> +
> + if (!hv_has_crashed && !lx_has_crashed)
> + return NMI_DONE; /* ignore the nmi */
> +
> + if (hv_has_crashed) {
> + if (!kexec_crash_loaded() || !hv_crash_enabled) {
> + if (ccpu == 0) {
> + native_wrmsrq(HV_X64_MSR_RESET, 1); /* reboot */
and here the machine will be reset, which in both cases won't allow to
collect the VMRS file, thus not allowing to debug nested hypervisor
failures.
Perhaps it worth keeping the state for any case (not just nested), but
the nested state should be preserved.
Thanks,
Stanislav
> --
> 2.36.1.vfs.0.0
>
^ permalink raw reply
* Re: [PATCH 5/5] x86/Hyper-V: Add Hyper-V specific hvcall to set backing page
From: Tianyu Lan @ 2025-09-18 17:11 UTC (permalink / raw)
To: Borislav Petkov
Cc: kys, haiyangz, wei.liu, decui, tglx, mingo, dave.hansen, x86, hpa,
arnd, Neeraj.Upadhyay, tiala, kvijayab, romank, linux-arch,
linux-hyperv, linux-kernel, Michael Kelley
In-Reply-To: <20250918150959.GEaMwgx78CGCxjGce8@fat_crate.local>
On Thu, Sep 18, 2025 at 11:10 PM Borislav Petkov <bp@alien8.de> wrote:
>
> On Thu, Sep 18, 2025 at 11:00:23AM -0400, Tianyu Lan wrote:
> > Secure AVIC hardware provides APIC backing page
> > to aid the guest in limiting which interrupt
> > vectors can be injected into the guest. Hyper-V
> > introduces a new register HV_X64_REGISTER_SEV_GPA_PAGE
> > to notify hypervisor with APIC backing page and call
> > it in Secure AVIC driver.
>
> Why does hyperv needs special handling again and cannot simply adhere to the
> secure AVIC spec?
>
> None of that text explains *why* it is absolutely necessary to do something
> hyperv-special...
Hyper-V uses a different hvcall to register an APIC backing page.
>
> > @@ -361,7 +364,11 @@ static void savic_setup(void)
> > * VMRUN, the hypervisor makes use of this information to make sure
> > * the APIC backing page is mapped in NPT.
> > */
> > - res = savic_register_gpa(gpa);
> > + if (hv_isolation_type_snp())
> > + res = hv_set_savic_backing_page(gfn);
> > + else
> > + res = savic_register_gpa(gpa);
> > +
>
> This is ugly and doesn't belong here.
>
Could I move the check into savic_register_gpa() or add a stub function
to check guest runs on Hyper-V or not and then call associated function
to register APIC backing page?
--
Thanks
Tianyu Lan
^ permalink raw reply
* Re: [PATCH 5/5] x86/Hyper-V: Add Hyper-V specific hvcall to set backing page
From: Borislav Petkov @ 2025-09-18 15:09 UTC (permalink / raw)
To: Tianyu Lan
Cc: kys, haiyangz, wei.liu, decui, tglx, mingo, dave.hansen, x86, hpa,
arnd, Neeraj.Upadhyay, tiala, kvijayab, romank, linux-arch,
linux-hyperv, linux-kernel
In-Reply-To: <20250918150023.474021-6-tiala@microsoft.com>
On Thu, Sep 18, 2025 at 11:00:23AM -0400, Tianyu Lan wrote:
> Secure AVIC hardware provides APIC backing page
> to aid the guest in limiting which interrupt
> vectors can be injected into the guest. Hyper-V
> introduces a new register HV_X64_REGISTER_SEV_GPA_PAGE
> to notify hypervisor with APIC backing page and call
> it in Secure AVIC driver.
Why does hyperv needs special handling again and cannot simply adhere to the
secure AVIC spec?
None of that text explains *why* it is absolutely necessary to do something
hyperv-special...
> @@ -361,7 +364,11 @@ static void savic_setup(void)
> * VMRUN, the hypervisor makes use of this information to make sure
> * the APIC backing page is mapped in NPT.
> */
> - res = savic_register_gpa(gpa);
> + if (hv_isolation_type_snp())
> + res = hv_set_savic_backing_page(gfn);
> + else
> + res = savic_register_gpa(gpa);
> +
This is ugly and doesn't belong here.
--
Regards/Gruss,
Boris.
https://people.kernel.org/tglx/notes-about-netiquette
^ permalink raw reply
* [PATCH 5/5] x86/Hyper-V: Add Hyper-V specific hvcall to set backing page
From: Tianyu Lan @ 2025-09-18 15:00 UTC (permalink / raw)
To: kys, haiyangz, wei.liu, decui, tglx, mingo, bp, dave.hansen, x86,
hpa, arnd, Neeraj.Upadhyay, tiala, kvijayab, romank
Cc: linux-arch, linux-hyperv, linux-kernel
In-Reply-To: <20250918150023.474021-1-tiala@microsoft.com>
Secure AVIC hardware provides APIC backing page
to aid the guest in limiting which interrupt
vectors can be injected into the guest. Hyper-V
introduces a new register HV_X64_REGISTER_SEV_GPA_PAGE
to notify hypervisor with APIC backing page and call
it in Secure AVIC driver.
Setting APIC backing page for APs takes place before
allocating hyperv_pcpu_input_arg and so allocate
hv_vp_early_input_arg to handle such case.
Signed-off-by: Roman Kisel <romank@linux.microsoft.com>
Signed-off-by: Tianyu Lan <tiala@microsoft.com>
---
arch/x86/hyperv/hv_init.c | 24 +++++++++++++++++-
arch/x86/hyperv/ivm.c | 38 ++++++++++++++++++++++++++++
arch/x86/include/asm/mshyperv.h | 2 ++
arch/x86/kernel/apic/x2apic_savic.c | 9 ++++++-
include/hyperv/hvgdk_mini.h | 39 +++++++++++++++++++++++++++++
5 files changed, 110 insertions(+), 2 deletions(-)
diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c
index a38bb96c9f5e..3fa8e91cd03f 100644
--- a/arch/x86/hyperv/hv_init.c
+++ b/arch/x86/hyperv/hv_init.c
@@ -39,6 +39,7 @@
void *hv_hypercall_pg;
EXPORT_SYMBOL_GPL(hv_hypercall_pg);
+void *hv_vp_early_input_arg;
union hv_ghcb * __percpu *hv_ghcb_pg;
/* Storage to save the hypercall page temporarily for hibernation */
@@ -412,6 +413,7 @@ void __init hyperv_init(void)
u64 guest_id;
union hv_x64_msr_hypercall_contents hypercall_msr;
int cpuhp;
+ int ret;
if (x86_hyper_type != X86_HYPER_MS_HYPERV)
return;
@@ -419,6 +421,22 @@ void __init hyperv_init(void)
if (hv_common_init())
return;
+ if (cc_platform_has(CC_ATTR_SNP_SECURE_AVIC)) {
+ hv_vp_early_input_arg = kcalloc(num_possible_cpus(),
+ PAGE_SIZE,
+ GFP_KERNEL);
+ if (hv_vp_early_input_arg) {
+ ret = set_memory_decrypted((u64)hv_vp_early_input_arg,
+ num_possible_cpus());
+ if (ret) {
+ kfree(hv_vp_early_input_arg);
+ goto common_free;
+ }
+ } else {
+ goto common_free;
+ }
+ }
+
/*
* The VP assist page is useless to a TDX guest: the only use we
* would have for it is lazy EOI, which can not be used with TDX.
@@ -433,7 +451,7 @@ void __init hyperv_init(void)
ms_hyperv.hints &= ~HV_X64_ENLIGHTENED_VMCS_RECOMMENDED;
if (!hv_isolation_type_tdx())
- goto common_free;
+ goto free_vp_early_input_arg;
}
if (ms_hyperv.paravisor_present && hv_isolation_type_snp()) {
@@ -591,6 +609,10 @@ void __init hyperv_init(void)
free_vp_assist_page:
kfree(hv_vp_assist_page);
hv_vp_assist_page = NULL;
+free_vp_early_input_arg:
+ set_memory_encrypted((u64)hv_vp_early_input_arg, num_possible_cpus());
+ kfree(hv_vp_early_input_arg);
+ hv_vp_early_input_arg = NULL;
common_free:
hv_common_free();
}
diff --git a/arch/x86/hyperv/ivm.c b/arch/x86/hyperv/ivm.c
index ade6c665c97e..e69dae57730c 100644
--- a/arch/x86/hyperv/ivm.c
+++ b/arch/x86/hyperv/ivm.c
@@ -291,6 +291,44 @@ static void snp_cleanup_vmsa(struct sev_es_save_area *vmsa)
free_page((unsigned long)vmsa);
}
+enum es_result hv_set_savic_backing_page(u64 gfn)
+{
+ u64 control = HV_HYPERCALL_REP_COMP_1 | HVCALL_SET_VP_REGISTERS;
+ struct hv_set_vp_registers_input *input
+ = hv_vp_early_input_arg + smp_processor_id() * PAGE_SIZE;
+ union hv_x64_register_sev_gpa_page value;
+ unsigned long flags;
+ int retry = 5;
+ u64 ret;
+
+ local_irq_save(flags);
+
+ value.enabled = 1;
+ value.reserved = 0;
+ value.pagenumber = gfn;
+
+ memset(input, 0, struct_size(input, element, 1));
+ input->header.partitionid = HV_PARTITION_ID_SELF;
+ input->header.vpindex = HV_VP_INDEX_SELF;
+ input->header.inputvtl = ms_hyperv.vtl;
+ input->element[0].name = HV_X64_REGISTER_SEV_AVIC_GPA;
+ input->element[0].value.reg64 = value.u64;
+
+ do {
+ ret = hv_do_hypercall(control, input, NULL);
+ } while (ret == HV_STATUS_TIME_OUT && retry--);
+
+ if (!hv_result_success(ret))
+ pr_err("Failed to set Secure AVIC backing page %llx.\n", ret);
+
+ local_irq_restore(flags);
+
+ if (hv_result_success(ret))
+ return ES_OK;
+ else
+ return ES_VMM_ERROR;
+}
+
int hv_snp_boot_ap(u32 apic_id, unsigned long start_ip, unsigned int cpu)
{
struct sev_es_save_area *vmsa = (struct sev_es_save_area *)
diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h
index abc4659f5809..b140558816de 100644
--- a/arch/x86/include/asm/mshyperv.h
+++ b/arch/x86/include/asm/mshyperv.h
@@ -43,6 +43,7 @@ static inline unsigned char hv_get_nmi_reason(void)
extern bool hyperv_paravisor_present;
extern void *hv_hypercall_pg;
+extern void *hv_vp_early_input_arg;
extern union hv_ghcb * __percpu *hv_ghcb_pg;
@@ -252,6 +253,7 @@ int hv_unmap_ioapic_interrupt(int ioapic_id, struct hv_interrupt_entry *entry);
bool hv_ghcb_negotiate_protocol(void);
void __noreturn hv_ghcb_terminate(unsigned int set, unsigned int reason);
int hv_snp_boot_ap(u32 apic_id, unsigned long start_ip, unsigned int cpu);
+enum es_result hv_set_savic_backing_page(u64 gfn);
#else
static inline bool hv_ghcb_negotiate_protocol(void) { return false; }
static inline void hv_ghcb_terminate(unsigned int set, unsigned int reason) {}
diff --git a/arch/x86/kernel/apic/x2apic_savic.c b/arch/x86/kernel/apic/x2apic_savic.c
index dbc5678bc3b6..60bdb524de53 100644
--- a/arch/x86/kernel/apic/x2apic_savic.c
+++ b/arch/x86/kernel/apic/x2apic_savic.c
@@ -14,6 +14,7 @@
#include <asm/apic.h>
#include <asm/sev.h>
+#include <asm/mshyperv.h>
#include "local.h"
@@ -342,6 +343,7 @@ static void savic_setup(void)
void *ap = this_cpu_ptr(savic_page);
enum es_result res;
unsigned long gpa;
+ unsigned long gfn;
/*
* Before Secure AVIC is enabled, APIC MSR reads are intercepted.
@@ -350,6 +352,7 @@ static void savic_setup(void)
apic_set_reg(ap, APIC_ID, native_apic_msr_read(APIC_ID));
gpa = __pa(ap);
+ gfn = gpa >> PAGE_SHIFT;
/*
* The NPT entry for a vCPU's APIC backing page must always be
@@ -361,7 +364,11 @@ static void savic_setup(void)
* VMRUN, the hypervisor makes use of this information to make sure
* the APIC backing page is mapped in NPT.
*/
- res = savic_register_gpa(gpa);
+ if (hv_isolation_type_snp())
+ res = hv_set_savic_backing_page(gfn);
+ else
+ res = savic_register_gpa(gpa);
+
if (res != ES_OK)
sev_es_terminate(SEV_TERM_SET_LINUX, GHCB_TERM_SAVIC_FAIL);
diff --git a/include/hyperv/hvgdk_mini.h b/include/hyperv/hvgdk_mini.h
index 1be7f6a02304..e3092469aafe 100644
--- a/include/hyperv/hvgdk_mini.h
+++ b/include/hyperv/hvgdk_mini.h
@@ -1170,6 +1170,28 @@ union hv_register_value {
union hv_arm64_pending_synthetic_exception_event pending_synthetic_exception_event;
};
+/* HvSetVpRegisters hypercall with variable size reg name/value list*/
+struct hv_set_vp_registers_input {
+ struct {
+ u64 partitionid;
+ u32 vpindex;
+ u8 inputvtl;
+ u8 padding[3];
+ } header;
+ struct {
+ u32 name;
+ u32 padding1;
+ u64 padding2;
+ union {
+ union hv_register_value value;
+ struct {
+ u64 valuelow;
+ u64 valuehigh;
+ };
+ };
+ } element[];
+} __packed;
+
/* NOTE: Linux helper struct - NOT from Hyper-V code. */
struct hv_output_get_vp_registers {
DECLARE_FLEX_ARRAY(union hv_register_value, values);
@@ -1210,6 +1232,15 @@ struct hv_input_get_vp_registers {
u32 names[];
} __packed;
+union hv_x64_register_sev_gpa_page {
+ u64 u64;
+ struct {
+ u64 enabled:1;
+ u64 reserved:11;
+ u64 pagenumber:52;
+ };
+} __packed;
+
struct hv_input_set_vp_registers {
u64 partition_id;
u32 vp_index;
@@ -1230,6 +1261,14 @@ struct hv_send_ipi { /* HV_INPUT_SEND_SYNTHETIC_CLUSTER_IPI */
#define HV_VTL_MASK GENMASK(3, 0)
+/*
+ * Registers are only accessible via HVCALL_GET_VP_REGISTERS hvcall and
+ * there is not associated MSR address.
+ */
+#define HV_X64_REGISTER_VSM_VP_STATUS 0x000D0003
+#define HV_X64_VTL_MASK GENMASK(3, 0)
+#define HV_X64_REGISTER_SEV_AVIC_GPA 0x00090043
+
/* Hyper-V memory host visibility */
enum hv_mem_host_visibility {
VMBUS_PAGE_NOT_VISIBLE = 0,
--
2.25.1
^ permalink raw reply related
* [PATCH 4/5] x86/hyperv: Allow Hyper-V to inject STIMER0 interrupts
From: Tianyu Lan @ 2025-09-18 15:00 UTC (permalink / raw)
To: kys, haiyangz, wei.liu, decui, tglx, mingo, bp, dave.hansen, x86,
hpa, arnd, Neeraj.Upadhyay, tiala, kvijayab, romank
Cc: linux-arch, linux-hyperv, linux-kernel, Michael Kelley
In-Reply-To: <20250918150023.474021-1-tiala@microsoft.com>
When Secure AVIC is enabled, call Secure AVIC
function to allow Hyper-V to inject STIMER0 interrupt.
Reviewed-by: Neeraj Upadhyay <Neeraj.Upadhyay@amd.com>
Reviewed-by: Michael Kelley <mhklinux@outlook.com>
Signed-off-by: Tianyu Lan <tiala@microsoft.com>
---
arch/x86/hyperv/hv_init.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c
index afdbda2dd7b7..a38bb96c9f5e 100644
--- a/arch/x86/hyperv/hv_init.c
+++ b/arch/x86/hyperv/hv_init.c
@@ -133,6 +133,10 @@ static int hv_cpu_init(unsigned int cpu)
wrmsrq(HV_X64_MSR_VP_ASSIST_PAGE, msr.as_uint64);
}
+ /* Allow Hyper-V stimer vector to be injected from Hypervisor. */
+ if (ms_hyperv.misc_features & HV_STIMER_DIRECT_MODE_AVAILABLE)
+ apic_update_vector(cpu, HYPERV_STIMER0_VECTOR, true);
+
return hyperv_init_ghcb();
}
@@ -240,6 +244,9 @@ static int hv_cpu_die(unsigned int cpu)
*ghcb_va = NULL;
}
+ if (ms_hyperv.misc_features & HV_STIMER_DIRECT_MODE_AVAILABLE)
+ apic_update_vector(cpu, HYPERV_STIMER0_VECTOR, false);
+
hv_common_cpu_die(cpu);
if (hv_vp_assist_page && hv_vp_assist_page[cpu]) {
--
2.25.1
^ permalink raw reply related
* [PATCH 3/5] x86/hyperv: Don't use auto-eoi when Secure AVIC is available
From: Tianyu Lan @ 2025-09-18 15:00 UTC (permalink / raw)
To: kys, haiyangz, wei.liu, decui, tglx, mingo, bp, dave.hansen, x86,
hpa, arnd, Neeraj.Upadhyay, tiala, kvijayab, romank
Cc: linux-arch, linux-hyperv, linux-kernel, Michael Kelley
In-Reply-To: <20250918150023.474021-1-tiala@microsoft.com>
Hyper-V doesn't support auto-eoi with Secure AVIC.
So set the HV_DEPRECATING_AEOI_RECOMMENDED flag
to force writing the EOI register after handling an interrupt.
Reviewed-by: Michael Kelley <mhklinux@outlook.com>
Reviewed-by: Neeraj Upadhyay <Neeraj.Upadhyay@amd.com>
Signed-off-by: Tianyu Lan <tiala@microsoft.com>
---
arch/x86/kernel/cpu/mshyperv.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c
index c78f860419d6..6dd3ae66a646 100644
--- a/arch/x86/kernel/cpu/mshyperv.c
+++ b/arch/x86/kernel/cpu/mshyperv.c
@@ -464,6 +464,9 @@ static void __init ms_hyperv_init_platform(void)
hv_identify_partition_type();
+ if (cc_platform_has(CC_ATTR_SNP_SECURE_AVIC))
+ ms_hyperv.hints |= HV_DEPRECATING_AEOI_RECOMMENDED;
+
if (ms_hyperv.hints & HV_X64_HYPERV_NESTED) {
hv_nested = true;
pr_info("Hyper-V: running on a nested hypervisor\n");
--
2.25.1
^ permalink raw reply related
* [PATCH 2/5] drivers: hv: Allow vmbus message synic interrupt injected from Hyper-V
From: Tianyu Lan @ 2025-09-18 15:00 UTC (permalink / raw)
To: kys, haiyangz, wei.liu, decui, tglx, mingo, bp, dave.hansen, x86,
hpa, arnd, Neeraj.Upadhyay, tiala, kvijayab, romank
Cc: linux-arch, linux-hyperv, linux-kernel, Michael Kelley
In-Reply-To: <20250918150023.474021-1-tiala@microsoft.com>
When Secure AVIC is enabled, VMBus driver should
call x2apic Secure AVIC interface to allow Hyper-V
to inject VMBus message interrupt.
Reviewed-by: Michael Kelley <mhklinux@outlook.com>
Reviewed-by: Neeraj Upadhyay <Neeraj.Upadhyay@amd.com>
Signed-off-by: Tianyu Lan <tiala@microsoft.com>
---
arch/x86/hyperv/hv_apic.c | 5 +++++
drivers/hv/hv.c | 2 ++
drivers/hv/hv_common.c | 5 +++++
include/asm-generic/mshyperv.h | 1 +
4 files changed, 13 insertions(+)
diff --git a/arch/x86/hyperv/hv_apic.c b/arch/x86/hyperv/hv_apic.c
index e669053b637d..a8de503def37 100644
--- a/arch/x86/hyperv/hv_apic.c
+++ b/arch/x86/hyperv/hv_apic.c
@@ -53,6 +53,11 @@ static void hv_apic_icr_write(u32 low, u32 id)
wrmsrq(HV_X64_MSR_ICR, reg_val);
}
+void hv_enable_coco_interrupt(unsigned int cpu, unsigned int vector, bool set)
+{
+ apic_update_vector(cpu, vector, set);
+}
+
static u32 hv_apic_read(u32 reg)
{
u32 reg_val, hi;
diff --git a/drivers/hv/hv.c b/drivers/hv/hv.c
index b14c5f9e0ef2..ec5d10839e0f 100644
--- a/drivers/hv/hv.c
+++ b/drivers/hv/hv.c
@@ -307,6 +307,7 @@ void hv_synic_enable_regs(unsigned int cpu)
}
hv_set_msr(HV_MSR_SIEFP, siefp.as_uint64);
+ hv_enable_coco_interrupt(cpu, vmbus_interrupt, true);
/* Setup the shared SINT. */
if (vmbus_irq != -1)
@@ -350,6 +351,7 @@ void hv_synic_disable_regs(unsigned int cpu)
/* Need to correctly cleanup in the case of SMP!!! */
/* Disable the interrupt */
hv_set_msr(HV_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64);
+ hv_enable_coco_interrupt(cpu, vmbus_interrupt, false);
simp.as_uint64 = hv_get_msr(HV_MSR_SIMP);
/*
diff --git a/drivers/hv/hv_common.c b/drivers/hv/hv_common.c
index 49898d10faff..0f024ab3d360 100644
--- a/drivers/hv/hv_common.c
+++ b/drivers/hv/hv_common.c
@@ -716,6 +716,11 @@ u64 __weak hv_tdx_hypercall(u64 control, u64 param1, u64 param2)
}
EXPORT_SYMBOL_GPL(hv_tdx_hypercall);
+void __weak hv_enable_coco_interrupt(unsigned int cpu, unsigned int vector, bool set)
+{
+}
+EXPORT_SYMBOL_GPL(hv_enable_coco_interrupt);
+
void hv_identify_partition_type(void)
{
/* Assume guest role */
diff --git a/include/asm-generic/mshyperv.h b/include/asm-generic/mshyperv.h
index a729b77983fa..7907c9878369 100644
--- a/include/asm-generic/mshyperv.h
+++ b/include/asm-generic/mshyperv.h
@@ -333,6 +333,7 @@ bool hv_is_isolation_supported(void);
bool hv_isolation_type_snp(void);
u64 hv_ghcb_hypercall(u64 control, void *input, void *output, u32 input_size);
u64 hv_tdx_hypercall(u64 control, u64 param1, u64 param2);
+void hv_enable_coco_interrupt(unsigned int cpu, unsigned int vector, bool set);
void hyperv_cleanup(void);
bool hv_query_ext_cap(u64 cap_query);
void hv_setup_dma_ops(struct device *dev, bool coherent);
--
2.25.1
^ permalink raw reply related
* [PATCH 1/5] x86/hyperv: Don't use hv apic driver when Secure AVIC is available
From: Tianyu Lan @ 2025-09-18 15:00 UTC (permalink / raw)
To: kys, haiyangz, wei.liu, decui, tglx, mingo, bp, dave.hansen, x86,
hpa, arnd, Neeraj.Upadhyay, tiala, kvijayab, romank
Cc: linux-arch, linux-hyperv, linux-kernel, Michael Kelley
In-Reply-To: <20250918150023.474021-1-tiala@microsoft.com>
When Secure AVIC is available, the AMD x2apic Secure
AVIC driver will be selected. In that case, have
hv_apic_init() return immediately without doing
anything.
Reviewed-by: Michael Kelley <mhklinux@outlook.com>
Reviewed-by: Neeraj Upadhyay <Neeraj.Upadhyay@amd.com>
Signed-off-by: Tianyu Lan <tiala@microsoft.com>
---
arch/x86/hyperv/hv_apic.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/arch/x86/hyperv/hv_apic.c b/arch/x86/hyperv/hv_apic.c
index bfde0a3498b9..e669053b637d 100644
--- a/arch/x86/hyperv/hv_apic.c
+++ b/arch/x86/hyperv/hv_apic.c
@@ -293,6 +293,9 @@ static void hv_send_ipi_self(int vector)
void __init hv_apic_init(void)
{
+ if (cc_platform_has(CC_ATTR_SNP_SECURE_AVIC))
+ return;
+
if (ms_hyperv.hints & HV_X64_CLUSTER_IPI_RECOMMENDED) {
pr_info("Hyper-V: Using IPI hypercalls\n");
/*
--
2.25.1
^ permalink raw reply related
* [PATCH 0/5] x86/Hyper-V: Add AMD Secure AVIC for Hyper-V platform
From: Tianyu Lan @ 2025-09-18 15:00 UTC (permalink / raw)
To: kys, haiyangz, wei.liu, decui, tglx, mingo, bp, dave.hansen, x86,
hpa, arnd, Neeraj.Upadhyay, tiala, kvijayab, romank
Cc: linux-arch, linux-hyperv
Secure AVIC is a new hardware feature in the AMD64
architecture to allow SEV-SNP guests to prevent the
hypervisor from generating unexpected interrupts to
a vCPU or otherwise violate architectural assumptions
around APIC behavior.
Each vCPU has a guest-allocated APIC backing page of
size 4K, which maintains APIC state for that vCPU.
APIC backing page's ALLOWED_IRR field indicates the
interrupt vectors which the guest allows the hypervisor
to send.
This patchset is to enable the feature for Hyper-V
platform. Patch "Drivers: hv: Allow vmbus message
synic interrupt injected from Hyper-V" is to expose
new fucntion hv_enable_coco_interrupt() and device
driver and arch code may update AVIC backing page
ALLOWED_IRR field to allow Hyper-V inject associated
vector.
The patchset is based on the tip tree commit 27a17e02418e
(x86/sev: Indicate the SEV-SNP guest supports Secure AVIC)
Tianyu Lan (5):
x86/hyperv: Don't use hv apic driver when Secure AVIC is available
drivers: hv: Allow vmbus message synic interrupt injected from Hyper-V
x86/hyperv: Don't use auto-eoi when Secure AVIC is available
x86/hyperv: Allow Hyper-V to inject STIMER0 interrupts
x86/Hyper-V: Add Hyper-V specific hvcall to set backing page
arch/x86/hyperv/hv_apic.c | 8 ++++++
arch/x86/hyperv/hv_init.c | 31 ++++++++++++++++++++++-
arch/x86/hyperv/ivm.c | 38 ++++++++++++++++++++++++++++
arch/x86/include/asm/mshyperv.h | 2 ++
arch/x86/kernel/apic/x2apic_savic.c | 9 ++++++-
arch/x86/kernel/cpu/mshyperv.c | 3 +++
drivers/hv/hv.c | 2 ++
drivers/hv/hv_common.c | 5 ++++
include/asm-generic/mshyperv.h | 1 +
include/hyperv/hvgdk_mini.h | 39 +++++++++++++++++++++++++++++
10 files changed, 136 insertions(+), 2 deletions(-)
--
2.25.1
^ permalink raw reply
* Re: [PATCH] x86/hyperv: Export hv_hypercall_pg unconditionally
From: James Bottomley @ 2025-09-18 14:21 UTC (permalink / raw)
To: Peter Zijlstra, Naman Jain
Cc: Sean Christopherson, Paolo Bonzini, Roman Kisel,
K . Y . Srinivasan, Haiyang Zhang, Wei Liu, Dexuan Cui,
Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen, x86,
H . Peter Anvin, linux-hyperv, linux-kernel, mhklinux
In-Reply-To: <20250918064713.GW3419281@noisy.programming.kicks-ass.net>
On Thu, 2025-09-18 at 08:47 +0200, Peter Zijlstra wrote:
> On Thu, Sep 18, 2025 at 11:33:18AM +0530, Naman Jain wrote:
>
> > Thank you so much Sean and Paolo for your valuable inputs. I will
> > try out these things. Summarizing the suggestions here:
> > * Use noinstr (no instrumentation)
> > * Have separate .S file
> > * Don't use "register asm".
> > * Use static calls for solving IBT problems
> > * RAX:RCX is probably ok to be used, considering ABI. Whether we
> > would still need to use STACK_FRAME_NON_STANDARD, I am not sure,
> > but I will see based on how it goes.
> >
> > I hope this addresses the concerns Peter raised. If there's
> > anything I might have missed, I'm happy to make further adjustments
> > if needed.
>
> It would be a definite improvement. I'm just *really* sad people
> still create interfaces like this, even though we've known for years
> how bad they are.
Thanks for that. Our only defence at Microsoft is that the hypervisor
ABI for this is 10 years old and counting.
> At some point we've really have to push back and say enough is
> enough.
Although we can't really do anything about the old ABI since we have
tons of things that use it, there is interest in Microsoft for co-
designing a new ABI that we could add to hyper-v for Linux use and
which would also be a part of bringing up and using virtual secure mode
(VSM) in KVM via the planes API. I was thinking the best way of
discussing it as a community would be the PUCK call, but if there are
alternative forums, we could use that as well. This is going to be
pretty long term: besides designing and testing a new ABI, we were
counting on Amazon upstreaming their VSM implementation for KVM and
we're a bit under resourced here if it turns out we have to do
everything.
Regards,
James
^ permalink raw reply
* Re: [PATCH 2/2] MAINTAINERS: Mark hyperv_fb driver Obsolete
From: Saurabh Singh Sengar @ 2025-09-18 8:05 UTC (permalink / raw)
To: Prasanna Kumar T S M
Cc: dri-devel, linux-hyperv, linux-fbdev, linux-kernel, mhklinux,
rdunlap, bartosz.golaszewski, gonzalo.silvalde, arnd, tzimmermann,
decui, wei.liu, deller, kys, haiyangz
In-Reply-To: <1758117804-20798-1-git-send-email-ptsm@linux.microsoft.com>
On Wed, Sep 17, 2025 at 07:03:24AM -0700, Prasanna Kumar T S M wrote:
> The hyperv_fb driver is deprecated in favor of Hyper-V DRM driver. Split
> the hyperv_fb entry from the hyperv drivers list, mark it obsolete.
>
> Signed-off-by: Prasanna Kumar T S M <ptsm@linux.microsoft.com>
> ---
> MAINTAINERS | 11 ++++++++++-
> 1 file changed, 10 insertions(+), 1 deletion(-)
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index f6206963efbf..aa9d0fa6020b 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -11424,7 +11424,6 @@ F: drivers/pci/controller/pci-hyperv-intf.c
> F: drivers/pci/controller/pci-hyperv.c
> F: drivers/scsi/storvsc_drv.c
> F: drivers/uio/uio_hv_generic.c
> -F: drivers/video/fbdev/hyperv_fb.c
> F: include/asm-generic/mshyperv.h
> F: include/clocksource/hyperv_timer.h
> F: include/hyperv/hvgdk.h
> @@ -11438,6 +11437,16 @@ F: include/uapi/linux/hyperv.h
> F: net/vmw_vsock/hyperv_transport.c
> F: tools/hv/
>
> +HYPER-V FRAMEBUFFER DRIVER
> +M: "K. Y. Srinivasan" <kys@microsoft.com>
> +M: Haiyang Zhang <haiyangz@microsoft.com>
> +M: Wei Liu <wei.liu@kernel.org>
> +M: Dexuan Cui <decui@microsoft.com>
> +L: linux-hyperv@vger.kernel.org
> +S: Obsolete
> +T: git git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux.git
> +F: drivers/video/fbdev/hyperv_fb.c
> +
> HYPERBUS SUPPORT
> M: Vignesh Raghavendra <vigneshr@ti.com>
> R: Tudor Ambarus <tudor.ambarus@linaro.org>
> --
> 2.49.0
Reviewed-by: Saurabh Sengar <ssengar@linux.microsoft.com>
^ permalink raw reply
* Re: [PATCH 1/2] fbdev/hyperv_fb: deprecate this in favor of Hyper-V DRM driver
From: Saurabh Singh Sengar @ 2025-09-18 8:04 UTC (permalink / raw)
To: Prasanna Kumar T S M
Cc: dri-devel, linux-hyperv, linux-fbdev, linux-kernel, mhklinux,
rdunlap, bartosz.golaszewski, gonzalo.silvalde, arnd, tzimmermann,
decui, wei.liu, deller, kys, haiyangz
In-Reply-To: <1758117785-20653-1-git-send-email-ptsm@linux.microsoft.com>
On Wed, Sep 17, 2025 at 07:03:05AM -0700, Prasanna Kumar T S M wrote:
> The Hyper-V DRM driver is available since kernel version 5.14 and it
> provides full KMS support and fbdev emulation via the DRM fbdev helpers.
> Deprecate this driver in favor of Hyper-V DRM driver.
>
> Signed-off-by: Prasanna Kumar T S M <ptsm@linux.microsoft.com>
> ---
> drivers/video/fbdev/Kconfig | 5 ++++-
> drivers/video/fbdev/hyperv_fb.c | 2 ++
> 2 files changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/video/fbdev/Kconfig b/drivers/video/fbdev/Kconfig
> index c21484d15f0c..48c1c7417f6d 100644
> --- a/drivers/video/fbdev/Kconfig
> +++ b/drivers/video/fbdev/Kconfig
> @@ -1773,13 +1773,16 @@ config FB_BROADSHEET
> a bridge adapter.
>
> config FB_HYPERV
> - tristate "Microsoft Hyper-V Synthetic Video support"
> + tristate "Microsoft Hyper-V Synthetic Video support (DEPRECATED)"
> depends on FB && HYPERV
> select DMA_CMA if HAVE_DMA_CONTIGUOUS && CMA
> select FB_IOMEM_HELPERS_DEFERRED
> help
> This framebuffer driver supports Microsoft Hyper-V Synthetic Video.
>
> + This driver is deprecated, please use the Hyper-V DRM driver at
> + drivers/gpu/drm/hyperv (CONFIG_DRM_HYPERV) instead.
> +
> config FB_SIMPLE
> tristate "Simple framebuffer support"
> depends on FB
> diff --git a/drivers/video/fbdev/hyperv_fb.c b/drivers/video/fbdev/hyperv_fb.c
> index 75338ffc703f..c99e2ea4b3de 100644
> --- a/drivers/video/fbdev/hyperv_fb.c
> +++ b/drivers/video/fbdev/hyperv_fb.c
> @@ -1357,6 +1357,8 @@ static int __init hvfb_drv_init(void)
> {
> int ret;
>
> + pr_warn("Deprecated: use Hyper-V DRM driver instead\n");
> +
> if (fb_modesetting_disabled("hyper_fb"))
> return -ENODEV;
>
> --
> 2.49.0
Thanks for the patch. I hope it makes to the next LTS as planned.
Reviewed-by: Saurabh Sengar <ssengar@linux.microsoft.com>
^ permalink raw reply
* Re: [PATCH] x86/hyperv: Export hv_hypercall_pg unconditionally
From: Peter Zijlstra @ 2025-09-18 6:47 UTC (permalink / raw)
To: Naman Jain
Cc: Sean Christopherson, Paolo Bonzini, Roman Kisel,
K . Y . Srinivasan, Haiyang Zhang, Wei Liu, Dexuan Cui,
Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen, x86,
H . Peter Anvin, linux-hyperv, linux-kernel, mhklinux
In-Reply-To: <56521d85-1da5-4d25-b100-7dbe62e34d1d@linux.microsoft.com>
On Thu, Sep 18, 2025 at 11:33:18AM +0530, Naman Jain wrote:
> Thank you so much Sean and Paolo for your valuable inputs. I will try
> out these things. Summarizing the suggestions here:
> * Use noinstr (no instrumentation)
> * Have separate .S file
> * Don't use "register asm".
> * Use static calls for solving IBT problems
> * RAX:RCX is probably ok to be used, considering ABI. Whether we would still
> need to use STACK_FRAME_NON_STANDARD, I am not sure, but I will see based on
> how it goes.
>
> I hope this addresses the concerns Peter raised. If there's anything I might
> have missed, I'm happy to make further adjustments if needed.
It would be a definite improvement. I'm just *really* sad people still
create interfaces like this, even though we've known for years how bad
they are.
At some point we've really have to push back and say enough is enough.
^ permalink raw reply
* Re: [PATCH] x86/hyperv: Export hv_hypercall_pg unconditionally
From: Naman Jain @ 2025-09-18 6:03 UTC (permalink / raw)
To: Sean Christopherson, Paolo Bonzini, Peter Zijlstra
Cc: Roman Kisel, K . Y . Srinivasan, Haiyang Zhang, Wei Liu,
Dexuan Cui, Thomas Gleixner, Ingo Molnar, Borislav Petkov,
Dave Hansen, x86, H . Peter Anvin, linux-hyperv, linux-kernel,
mhklinux
In-Reply-To: <aMl5ulY1K7cKcMfo@google.com>
On 9/16/2025 8:22 PM, Sean Christopherson wrote:
> On Tue, Sep 16, 2025, Paolo Bonzini wrote:
>> On 8/27/25 01:04, Roman Kisel wrote:
>>> On 8/26/2025 5:07 AM, Peter Zijlstra wrote:
>>>> I do not know what OpenHCL is. Nor is it clear from the code what NMIs
>>>> can't happen. Anyway, same can be achieved with breakpoints / kprobes.
>>>> You can get a trap after setting CR2 and scribble it.
>>>>
>>>> You simply cannot use CR2 this way.
>>>
>>> The code in question runs with interrupts disabled, and the kernel runs
>>> without the memory swapping when using that module - the kernel is
>>> a firmware to host a vTPM for virtual machines. Somewhat similar to SMM.
>>> That should've been reflected somewhere in the comments and in Kconfig,
>>> we could do better. All in all, the page fault cannot happen in that
>>> path thus CR2 won't be trashed.
>>>
>>> Nor this kind of code can be stepped through in a self-hosted
>>> kernel debugger like kgdb. There are other examples of such code iiuc:
>>
>> As Sean mentioned, you do have to make sure that this is annotated as
>> noinstr (not instrumentable). And also just use assembly - KVM started with
>> a similar asm block, though without the sketchy "register asm",
>
> Ooh, yeah, don't use "register asm". I missed that when I peeked at the code.
> Using "register asm" will most definitely cause problems, because the compiler
> doesn't track usage in C code, i.e. will happily use the GPR and clobber your
> asm value in the process. That inevitably leads to very confusing and somewhat
> transient errors. E.g. if someone inserts a printk for debugging, the call to
> printk can clobber the very state it's trying to print.
>
>> and I was initially skeptical but using a dedicated .S file was absolutely
>> the right thing to do.
>
> +1000 to putting the assembly in a .S file. I too was a bit skeptical about
> moving the entire sequence into proper assembly; thankfully, some non-KVM folks
> talked us into it :-)
Thank you so much Sean and Paolo for your valuable inputs. I will try
out these things. Summarizing the suggestions here:
* Use noinstr (no instrumentation)
* Have separate .S file
* Don't use "register asm".
* Use static calls for solving IBT problems
* RAX:RCX is probably ok to be used, considering ABI. Whether we would
still need to use STACK_FRAME_NON_STANDARD, I am not sure, but I will
see based on how it goes.
I hope this addresses the concerns Peter raised. If there's anything I
might have missed, I'm happy to make further adjustments if needed.
Regards,
Naman
^ permalink raw reply
* Re: [PATCH v2 21/21] x86/pvlocks: Move paravirt spinlock functions into own header
From: Juergen Gross @ 2025-09-18 5:56 UTC (permalink / raw)
To: kernel test robot, linux-kernel, x86, linux-hyperv,
virtualization, kvm
Cc: llvm, oe-kbuild-all, K. Y. Srinivasan, Haiyang Zhang, Wei Liu,
Dexuan Cui, Thomas Gleixner, Ingo Molnar, Borislav Petkov,
Dave Hansen, H. Peter Anvin, Ajay Kaher, Alexey Makhalov,
Broadcom internal kernel review list, Paolo Bonzini,
Vitaly Kuznetsov, Boris Ostrovsky, Josh Poimboeuf, xen-devel
In-Reply-To: <202509181008.MoLd2u4e-lkp@intel.com>
[-- Attachment #1.1.1: Type: text/plain, Size: 2124 bytes --]
On 18.09.25 04:45, kernel test robot wrote:
> Hi Juergen,
>
> kernel test robot noticed the following build warnings:
>
> [auto build test WARNING on tip/sched/core]
> [also build test WARNING on kvm/queue kvm/next linus/master v6.17-rc6 next-20250917]
> [cannot apply to tip/x86/core kvm/linux-next]
> [If your patch is applied to the wrong git tree, kindly drop us a note.
> And when submitting patch, we suggest to use '--base' as documented in
> https://git-scm.com/docs/git-format-patch#_base_tree_information]
>
> url: https://github.com/intel-lab-lkp/linux/commits/Juergen-Gross/x86-paravirt-Remove-not-needed-includes-of-paravirt-h/20250917-230321
> base: tip/sched/core
> patch link: https://lore.kernel.org/r/20250917145220.31064-22-jgross%40suse.com
> patch subject: [PATCH v2 21/21] x86/pvlocks: Move paravirt spinlock functions into own header
> config: x86_64-randconfig-003-20250918 (https://download.01.org/0day-ci/archive/20250918/202509181008.MoLd2u4e-lkp@intel.com/config)
> compiler: clang version 20.1.8 (https://github.com/llvm/llvm-project 87f0227cb60147a26a1eeb4fb06e3b505e9c7261)
> reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250918/202509181008.MoLd2u4e-lkp@intel.com/reproduce)
>
> If you fix the issue in a separate patch/commit (i.e. not just a new version of
> the same patch/commit), kindly add following tags
> | Reported-by: kernel test robot <lkp@intel.com>
> | Closes: https://lore.kernel.org/oe-kbuild-all/202509181008.MoLd2u4e-lkp@intel.com/
>
> All warnings (new ones prefixed by >>):
>
>>> arch/x86/kernel/paravirt-spinlocks.c:13:13: warning: no previous prototype for function 'native_pv_lock_init' [-Wmissing-prototypes]
> 13 | void __init native_pv_lock_init(void)
> | ^
> arch/x86/kernel/paravirt-spinlocks.c:13:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
> 13 | void __init native_pv_lock_init(void)
> | ^
> | static
> 1 warning generated.
Will be fixed in V3.
Juergen
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^ permalink raw reply
* Re: [PATCH v2 21/21] x86/pvlocks: Move paravirt spinlock functions into own header
From: kernel test robot @ 2025-09-18 5:38 UTC (permalink / raw)
To: Juergen Gross, linux-kernel, x86, linux-hyperv, virtualization,
kvm
Cc: llvm, oe-kbuild-all, Juergen Gross, K. Y. Srinivasan,
Haiyang Zhang, Wei Liu, Dexuan Cui, Thomas Gleixner, Ingo Molnar,
Borislav Petkov, Dave Hansen, H. Peter Anvin, Ajay Kaher,
Alexey Makhalov, Broadcom internal kernel review list,
Paolo Bonzini, Vitaly Kuznetsov, Boris Ostrovsky, Josh Poimboeuf,
Peter Zijlstra, xen-devel
In-Reply-To: <20250917145220.31064-22-jgross@suse.com>
Hi Juergen,
kernel test robot noticed the following build errors:
[auto build test ERROR on tip/sched/core]
[also build test ERROR on kvm/queue kvm/next linus/master v6.17-rc6 next-20250917]
[cannot apply to tip/x86/core kvm/linux-next]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Juergen-Gross/x86-paravirt-Remove-not-needed-includes-of-paravirt-h/20250917-230321
base: tip/sched/core
patch link: https://lore.kernel.org/r/20250917145220.31064-22-jgross%40suse.com
patch subject: [PATCH v2 21/21] x86/pvlocks: Move paravirt spinlock functions into own header
config: x86_64-allnoconfig (https://download.01.org/0day-ci/archive/20250918/202509181317.YubLCpdh-lkp@intel.com/config)
compiler: clang version 20.1.8 (https://github.com/llvm/llvm-project 87f0227cb60147a26a1eeb4fb06e3b505e9c7261)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250918/202509181317.YubLCpdh-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202509181317.YubLCpdh-lkp@intel.com/
All errors (new ones prefixed by >>):
In file included from arch/x86/kernel/alternative.c:4:
In file included from include/linux/mmu_context.h:5:
arch/x86/include/asm/mmu_context.h:225:2: error: call to undeclared function 'paravirt_enter_mmap'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
225 | paravirt_enter_mmap(mm);
| ^
arch/x86/include/asm/mmu_context.h:232:2: error: call to undeclared function 'paravirt_arch_exit_mmap'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
232 | paravirt_arch_exit_mmap(mm);
| ^
arch/x86/include/asm/mmu_context.h:232:2: note: did you mean 'ldt_arch_exit_mmap'?
arch/x86/include/asm/mmu_context.h:61:6: note: 'ldt_arch_exit_mmap' declared here
61 | void ldt_arch_exit_mmap(struct mm_struct *mm);
| ^
In file included from arch/x86/kernel/alternative.c:5:
In file included from include/linux/perf_event.h:53:
In file included from include/linux/security.h:35:
In file included from include/linux/bpf.h:33:
In file included from arch/x86/include/asm/rqspinlock.h:5:
arch/x86/include/asm/paravirt.h:570:20: error: static declaration of 'paravirt_enter_mmap' follows non-static declaration
570 | static inline void paravirt_enter_mmap(struct mm_struct *mm)
| ^
arch/x86/include/asm/mmu_context.h:225:2: note: previous implicit declaration is here
225 | paravirt_enter_mmap(mm);
| ^
In file included from arch/x86/kernel/alternative.c:5:
In file included from include/linux/perf_event.h:53:
In file included from include/linux/security.h:35:
In file included from include/linux/bpf.h:33:
In file included from arch/x86/include/asm/rqspinlock.h:5:
arch/x86/include/asm/paravirt.h:576:20: error: static declaration of 'paravirt_arch_exit_mmap' follows non-static declaration
576 | static inline void paravirt_arch_exit_mmap(struct mm_struct *mm)
| ^
arch/x86/include/asm/mmu_context.h:232:2: note: previous implicit declaration is here
232 | paravirt_arch_exit_mmap(mm);
| ^
>> arch/x86/kernel/alternative.c:2317:2: error: call to undeclared function 'paravirt_set_cap'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
2317 | paravirt_set_cap();
| ^
arch/x86/kernel/alternative.c:2317:2: note: did you mean 'paravirt_ret0'?
arch/x86/include/asm/paravirt-base.h:23:15: note: 'paravirt_ret0' declared here
23 | unsigned long paravirt_ret0(void);
| ^
5 errors generated.
vim +/paravirt_set_cap +2317 arch/x86/kernel/alternative.c
270a69c4485d7d arch/x86/kernel/alternative.c Peter Zijlstra 2023-02-08 2288
9a0b5817ad97bb arch/i386/kernel/alternative.c Gerd Hoffmann 2006-03-23 2289 void __init alternative_instructions(void)
9a0b5817ad97bb arch/i386/kernel/alternative.c Gerd Hoffmann 2006-03-23 2290 {
ebebe30794d38c arch/x86/kernel/alternative.c Pawan Gupta 2025-05-03 2291 u64 ibt;
ebebe30794d38c arch/x86/kernel/alternative.c Pawan Gupta 2025-05-03 2292
7457c0da024b18 arch/x86/kernel/alternative.c Peter Zijlstra 2019-05-03 2293 int3_selftest();
7457c0da024b18 arch/x86/kernel/alternative.c Peter Zijlstra 2019-05-03 2294
7457c0da024b18 arch/x86/kernel/alternative.c Peter Zijlstra 2019-05-03 2295 /*
7457c0da024b18 arch/x86/kernel/alternative.c Peter Zijlstra 2019-05-03 2296 * The patching is not fully atomic, so try to avoid local
7457c0da024b18 arch/x86/kernel/alternative.c Peter Zijlstra 2019-05-03 2297 * interruptions that might execute the to be patched code.
7457c0da024b18 arch/x86/kernel/alternative.c Peter Zijlstra 2019-05-03 2298 * Other CPUs are not running.
7457c0da024b18 arch/x86/kernel/alternative.c Peter Zijlstra 2019-05-03 2299 */
8f4e956b313dcc arch/i386/kernel/alternative.c Andi Kleen 2007-07-22 2300 stop_nmi();
123aa76ec0cab5 arch/x86/kernel/alternative.c Andi Kleen 2009-02-12 2301
123aa76ec0cab5 arch/x86/kernel/alternative.c Andi Kleen 2009-02-12 2302 /*
123aa76ec0cab5 arch/x86/kernel/alternative.c Andi Kleen 2009-02-12 2303 * Don't stop machine check exceptions while patching.
123aa76ec0cab5 arch/x86/kernel/alternative.c Andi Kleen 2009-02-12 2304 * MCEs only happen when something got corrupted and in this
123aa76ec0cab5 arch/x86/kernel/alternative.c Andi Kleen 2009-02-12 2305 * case we must do something about the corruption.
32b1cbe380417f arch/x86/kernel/alternative.c Marco Ammon 2019-09-02 2306 * Ignoring it is worse than an unlikely patching race.
123aa76ec0cab5 arch/x86/kernel/alternative.c Andi Kleen 2009-02-12 2307 * Also machine checks tend to be broadcast and if one CPU
123aa76ec0cab5 arch/x86/kernel/alternative.c Andi Kleen 2009-02-12 2308 * goes into machine check the others follow quickly, so we don't
123aa76ec0cab5 arch/x86/kernel/alternative.c Andi Kleen 2009-02-12 2309 * expect a machine check to cause undue problems during to code
123aa76ec0cab5 arch/x86/kernel/alternative.c Andi Kleen 2009-02-12 2310 * patching.
123aa76ec0cab5 arch/x86/kernel/alternative.c Andi Kleen 2009-02-12 2311 */
8f4e956b313dcc arch/i386/kernel/alternative.c Andi Kleen 2007-07-22 2312
4e6292114c7412 arch/x86/kernel/alternative.c Juergen Gross 2021-03-11 2313 /*
f7af6977621a41 arch/x86/kernel/alternative.c Juergen Gross 2023-12-10 2314 * Make sure to set (artificial) features depending on used paravirt
f7af6977621a41 arch/x86/kernel/alternative.c Juergen Gross 2023-12-10 2315 * functions which can later influence alternative patching.
4e6292114c7412 arch/x86/kernel/alternative.c Juergen Gross 2021-03-11 2316 */
4e6292114c7412 arch/x86/kernel/alternative.c Juergen Gross 2021-03-11 @2317 paravirt_set_cap();
4e6292114c7412 arch/x86/kernel/alternative.c Juergen Gross 2021-03-11 2318
ebebe30794d38c arch/x86/kernel/alternative.c Pawan Gupta 2025-05-03 2319 /* Keep CET-IBT disabled until caller/callee are patched */
ebebe30794d38c arch/x86/kernel/alternative.c Pawan Gupta 2025-05-03 2320 ibt = ibt_save(/*disable*/ true);
ebebe30794d38c arch/x86/kernel/alternative.c Pawan Gupta 2025-05-03 2321
931ab63664f02b arch/x86/kernel/alternative.c Peter Zijlstra 2022-10-27 2322 __apply_fineibt(__retpoline_sites, __retpoline_sites_end,
1d7e707af44613 arch/x86/kernel/alternative.c Mike Rapoport (Microsoft 2025-01-26 2323) __cfi_sites, __cfi_sites_end, true);
931ab63664f02b arch/x86/kernel/alternative.c Peter Zijlstra 2022-10-27 2324
7508500900814d arch/x86/kernel/alternative.c Peter Zijlstra 2021-10-26 2325 /*
7508500900814d arch/x86/kernel/alternative.c Peter Zijlstra 2021-10-26 2326 * Rewrite the retpolines, must be done before alternatives since
7508500900814d arch/x86/kernel/alternative.c Peter Zijlstra 2021-10-26 2327 * those can rewrite the retpoline thunks.
7508500900814d arch/x86/kernel/alternative.c Peter Zijlstra 2021-10-26 2328 */
1d7e707af44613 arch/x86/kernel/alternative.c Mike Rapoport (Microsoft 2025-01-26 2329) apply_retpolines(__retpoline_sites, __retpoline_sites_end);
1d7e707af44613 arch/x86/kernel/alternative.c Mike Rapoport (Microsoft 2025-01-26 2330) apply_returns(__return_sites, __return_sites_end);
7508500900814d arch/x86/kernel/alternative.c Peter Zijlstra 2021-10-26 2331
a82b26451de126 arch/x86/kernel/alternative.c Peter Zijlstra (Intel 2025-06-03 2332) its_fini_core();
a82b26451de126 arch/x86/kernel/alternative.c Peter Zijlstra (Intel 2025-06-03 2333)
e81dc127ef6988 arch/x86/kernel/alternative.c Thomas Gleixner 2022-09-15 2334 /*
ab9fea59487d8b arch/x86/kernel/alternative.c Peter Zijlstra 2025-02-07 2335 * Adjust all CALL instructions to point to func()-10, including
ab9fea59487d8b arch/x86/kernel/alternative.c Peter Zijlstra 2025-02-07 2336 * those in .altinstr_replacement.
e81dc127ef6988 arch/x86/kernel/alternative.c Thomas Gleixner 2022-09-15 2337 */
e81dc127ef6988 arch/x86/kernel/alternative.c Thomas Gleixner 2022-09-15 2338 callthunks_patch_builtin_calls();
e81dc127ef6988 arch/x86/kernel/alternative.c Thomas Gleixner 2022-09-15 2339
ab9fea59487d8b arch/x86/kernel/alternative.c Peter Zijlstra 2025-02-07 2340 apply_alternatives(__alt_instructions, __alt_instructions_end);
ab9fea59487d8b arch/x86/kernel/alternative.c Peter Zijlstra 2025-02-07 2341
be0fffa5ca894a arch/x86/kernel/alternative.c Peter Zijlstra 2023-06-22 2342 /*
be0fffa5ca894a arch/x86/kernel/alternative.c Peter Zijlstra 2023-06-22 2343 * Seal all functions that do not have their address taken.
be0fffa5ca894a arch/x86/kernel/alternative.c Peter Zijlstra 2023-06-22 2344 */
1d7e707af44613 arch/x86/kernel/alternative.c Mike Rapoport (Microsoft 2025-01-26 2345) apply_seal_endbr(__ibt_endbr_seal, __ibt_endbr_seal_end);
ed53a0d971926e arch/x86/kernel/alternative.c Peter Zijlstra 2022-03-08 2346
ebebe30794d38c arch/x86/kernel/alternative.c Pawan Gupta 2025-05-03 2347 ibt_restore(ibt);
ebebe30794d38c arch/x86/kernel/alternative.c Pawan Gupta 2025-05-03 2348
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
^ permalink raw reply
* RE: [PATCH 6/6] scsi: storvsc: Remove redundant ternary operators
From: Michael Kelley @ 2025-09-18 4:06 UTC (permalink / raw)
To: Liao Yuanhong, K. Y. Srinivasan, Haiyang Zhang, Wei Liu,
Dexuan Cui, James E.J. Bottomley, Martin K. Petersen,
open list:Hyper-V/Azure CORE AND DRIVERS,
open list:SCSI SUBSYSTEM, open list
In-Reply-To: <20250902132359.83059-7-liaoyuanhong@vivo.com>
From: Liao Yuanhong <liaoyuanhong@vivo.com> Sent: Tuesday, September 2, 2025 6:24 AM
>
> Remove redundant ternary operators to clean up the code.
>
> Signed-off-by: Liao Yuanhong <liaoyuanhong@vivo.com>
> ---
> drivers/scsi/storvsc_drv.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c
> index d9e59204a9c3..7449743930d2 100644
> --- a/drivers/scsi/storvsc_drv.c
> +++ b/drivers/scsi/storvsc_drv.c
> @@ -1941,8 +1941,8 @@ static int storvsc_probe(struct hv_device *device,
> int num_present_cpus = num_present_cpus();
> struct Scsi_Host *host;
> struct hv_host_device *host_dev;
> - bool dev_is_ide = ((dev_id->driver_data == IDE_GUID) ? true : false);
> - bool is_fc = ((dev_id->driver_data == SFC_GUID) ? true : false);
> + bool dev_is_ide = dev_id->driver_data == IDE_GUID;
> + bool is_fc = dev_id->driver_data == SFC_GUID;
> int target = 0;
> struct storvsc_device *stor_device;
> int max_sub_channels = 0;
> --
> 2.34.1
>
Reviewed-by: Michael Kelley <mhklinux@outlook.com>
^ permalink raw reply
* RE: [PATCH 2/2] MAINTAINERS: Mark hyperv_fb driver Obsolete
From: Michael Kelley @ 2025-09-18 4:03 UTC (permalink / raw)
To: Prasanna Kumar T S M, dri-devel@lists.freedesktop.org,
linux-hyperv@vger.kernel.org, linux-fbdev@vger.kernel.org,
linux-kernel@vger.kernel.org, ssengar@linux.microsoft.com,
rdunlap@infradead.org, bartosz.golaszewski@linaro.org,
gonzalo.silvalde@gmail.com, arnd@arndb.de, tzimmermann@suse.de,
decui@microsoft.com, wei.liu@kernel.org, deller@gmx.de,
kys@microsoft.com, haiyangz@microsoft.com
In-Reply-To: <1758117804-20798-1-git-send-email-ptsm@linux.microsoft.com>
From: Prasanna Kumar T S M <ptsm@linux.microsoft.com> Sent: Wednesday, September 17, 2025 7:03 AM
>
> The hyperv_fb driver is deprecated in favor of Hyper-V DRM driver. Split
> the hyperv_fb entry from the hyperv drivers list, mark it obsolete.
>
> Signed-off-by: Prasanna Kumar T S M <ptsm@linux.microsoft.com>
> ---
> MAINTAINERS | 11 ++++++++++-
> 1 file changed, 10 insertions(+), 1 deletion(-)
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index f6206963efbf..aa9d0fa6020b 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -11424,7 +11424,6 @@ F: drivers/pci/controller/pci-hyperv-intf.c
> F: drivers/pci/controller/pci-hyperv.c
> F: drivers/scsi/storvsc_drv.c
> F: drivers/uio/uio_hv_generic.c
> -F: drivers/video/fbdev/hyperv_fb.c
> F: include/asm-generic/mshyperv.h
> F: include/clocksource/hyperv_timer.h
> F: include/hyperv/hvgdk.h
> @@ -11438,6 +11437,16 @@ F: include/uapi/linux/hyperv.h
> F: net/vmw_vsock/hyperv_transport.c
> F: tools/hv/
>
> +HYPER-V FRAMEBUFFER DRIVER
> +M: "K. Y. Srinivasan" <kys@microsoft.com>
> +M: Haiyang Zhang <haiyangz@microsoft.com>
> +M: Wei Liu <wei.liu@kernel.org>
> +M: Dexuan Cui <decui@microsoft.com>
> +L: linux-hyperv@vger.kernel.org
> +S: Obsolete
> +T: git git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux.git
> +F: drivers/video/fbdev/hyperv_fb.c
> +
> HYPERBUS SUPPORT
> M: Vignesh Raghavendra <vigneshr@ti.com>
> R: Tudor Ambarus <tudor.ambarus@linaro.org>
> --
> 2.49.0
Reviewed-by: Michael Kelley <mhklinux@outlook.com>
^ permalink raw reply
* RE: [PATCH 1/2] fbdev/hyperv_fb: deprecate this in favor of Hyper-V DRM driver
From: Michael Kelley @ 2025-09-18 4:01 UTC (permalink / raw)
To: Prasanna Kumar T S M, dri-devel@lists.freedesktop.org,
linux-hyperv@vger.kernel.org, linux-fbdev@vger.kernel.org,
linux-kernel@vger.kernel.org, ssengar@linux.microsoft.com,
rdunlap@infradead.org, bartosz.golaszewski@linaro.org,
gonzalo.silvalde@gmail.com, arnd@arndb.de, tzimmermann@suse.de,
decui@microsoft.com, wei.liu@kernel.org, deller@gmx.de,
kys@microsoft.com, haiyangz@microsoft.com
In-Reply-To: <1758117785-20653-1-git-send-email-ptsm@linux.microsoft.com>
From: Prasanna Kumar T S M <ptsm@linux.microsoft.com> Sent: Wednesday, September 17, 2025 7:03 AM
>
> The Hyper-V DRM driver is available since kernel version 5.14 and it
> provides full KMS support and fbdev emulation via the DRM fbdev helpers.
> Deprecate this driver in favor of Hyper-V DRM driver.
>
> Signed-off-by: Prasanna Kumar T S M <ptsm@linux.microsoft.com>
> ---
> drivers/video/fbdev/Kconfig | 5 ++++-
> drivers/video/fbdev/hyperv_fb.c | 2 ++
> 2 files changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/video/fbdev/Kconfig b/drivers/video/fbdev/Kconfig
> index c21484d15f0c..48c1c7417f6d 100644
> --- a/drivers/video/fbdev/Kconfig
> +++ b/drivers/video/fbdev/Kconfig
> @@ -1773,13 +1773,16 @@ config FB_BROADSHEET
> a bridge adapter.
>
> config FB_HYPERV
> - tristate "Microsoft Hyper-V Synthetic Video support"
> + tristate "Microsoft Hyper-V Synthetic Video support (DEPRECATED)"
> depends on FB && HYPERV
> select DMA_CMA if HAVE_DMA_CONTIGUOUS && CMA
> select FB_IOMEM_HELPERS_DEFERRED
> help
> This framebuffer driver supports Microsoft Hyper-V Synthetic Video.
>
> + This driver is deprecated, please use the Hyper-V DRM driver at
> + drivers/gpu/drm/hyperv (CONFIG_DRM_HYPERV) instead.
> +
> config FB_SIMPLE
> tristate "Simple framebuffer support"
> depends on FB
> diff --git a/drivers/video/fbdev/hyperv_fb.c b/drivers/video/fbdev/hyperv_fb.c
> index 75338ffc703f..c99e2ea4b3de 100644
> --- a/drivers/video/fbdev/hyperv_fb.c
> +++ b/drivers/video/fbdev/hyperv_fb.c
> @@ -1357,6 +1357,8 @@ static int __init hvfb_drv_init(void)
> {
> int ret;
>
> + pr_warn("Deprecated: use Hyper-V DRM driver instead\n");
> +
> if (fb_modesetting_disabled("hyper_fb"))
> return -ENODEV;
>
> --
> 2.49.0
Reviewed-by: Michael Kelley <mhklinux@outlook.com>
^ permalink raw reply
* RE: [PATCH 3/3] drivers: hv: vmbus: Fix typos in vmbus_drv.c
From: Michael Kelley @ 2025-09-18 3:53 UTC (permalink / raw)
To: Alok Tiwari, kys@microsoft.com, haiyangz@microsoft.com,
wei.liu@kernel.org, decui@microsoft.com,
linux-hyperv@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
In-Reply-To: <20250913192450.4134957-3-alok.a.tiwari@oracle.com>
From: Alok Tiwari <alok.a.tiwari@oracle.com> Sent: Saturday, September 13, 2025 12:25 PM
> To: kys@microsoft.com; haiyangz@microsoft.com; wei.liu@kernel.org;
> decui@microsoft.com; linux-hyperv@vger.kernel.org
> Cc: alok.a.tiwari@oracle.com; linux-kernel@vger.kernel.org
> Subject: [PATCH 3/3] drivers: hv: vmbus: Fix typos in vmbus_drv.c
>
> Fix two minor typos in vmbus_drv.c:
> - Correct "reponsible" -> "responsible" in a comment.
> - Add missing newline in pr_err() message ("channeln" -> "channel\n").
>
> These are cosmetic changes only and do not affect functionality.
>
> Signed-off-by: Alok Tiwari <alok.a.tiwari@oracle.com>
> ---
> drivers/hv/vmbus_drv.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
> index fbab9f2d7fa6..69591dc7bad2 100644
> --- a/drivers/hv/vmbus_drv.c
> +++ b/drivers/hv/vmbus_drv.c
> @@ -1947,7 +1947,7 @@ static const struct kobj_type vmbus_chan_ktype = {
> * is running.
> * For example, HV_NIC device is used either by uio_hv_generic or hv_netvsc at any given point of
> * time, and "ring" sysfs is needed only when uio_hv_generic is bound to that device. To avoid
> - * exposing the ring buffer by default, this function is reponsible to enable visibility of
> + * exposing the ring buffer by default, this function is responsible to enable visibility of
> * ring for userspace to use.
> * Note: Race conditions can happen with userspace and it is not encouraged to create new
> * use-cases for this. This was added to maintain backward compatibility, while solving
> @@ -2110,7 +2110,7 @@ int vmbus_device_register(struct hv_device *child_device_obj)
> ret = vmbus_add_channel_kobj(child_device_obj,
> child_device_obj->channel);
> if (ret) {
> - pr_err("Unable to register primary channeln");
> + pr_err("Unable to register primary channel\n");
> goto err_kset_unregister;
> }
> hv_debug_add_dev_dir(child_device_obj);
> --
> 2.50.1
>
Reviewed-by: Michael Kelley <mhklinux@outlook.com>
^ permalink raw reply
* RE: [PATCH v2] drivers: hv: vmbus: Clean up sscanf format specifier in target_cpu_store()
From: Michael Kelley @ 2025-09-18 3:51 UTC (permalink / raw)
To: Alok Tiwari, kys@microsoft.com, haiyangz@microsoft.com,
wei.liu@kernel.org, decui@microsoft.com,
linux-hyperv@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
In-Reply-To: <20250917085933.129306-1-alok.a.tiwari@oracle.com>
From: Alok Tiwari <alok.a.tiwari@oracle.com> Sent: Wednesday, September 17, 2025 2:00 AM
>
> The target_cpu_store() function parses the target CPU from the sysfs
> buffer using sscanf(). The format string currently uses "%uu", which
> is redundant. The compiler ignores the extra "u", so there is no
> incorrect parsing at runtime.
>
> Update the format string to use "%u" for clarity and consistency.
>
> Signed-off-by: Alok Tiwari <alok.a.tiwari@oracle.com>
> ---
> v1 -> v2
> Rephrase commit message and subject to clarify
> that there is no incorrect parsing at runtime.
> ---
> drivers/hv/vmbus_drv.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
> index 5b4f8d009ca5..69591dc7bad2 100644
> --- a/drivers/hv/vmbus_drv.c
> +++ b/drivers/hv/vmbus_drv.c
> @@ -1742,7 +1742,7 @@ static ssize_t target_cpu_store(struct vmbus_channel *channel,
> u32 target_cpu;
> ssize_t ret;
>
> - if (sscanf(buf, "%uu", &target_cpu) != 1)
> + if (sscanf(buf, "%u", &target_cpu) != 1)
> return -EIO;
>
> cpus_read_lock();
> --
> 2.50.1
Reviewed-by: Michael Kelley <mhklinux@outlook.com>
^ permalink raw reply
* RE: [PATCH 1/3] drivers: hv: vmbus: Fix sysfs output format for ring buffer index
From: Michael Kelley @ 2025-09-18 3:49 UTC (permalink / raw)
To: Alok Tiwari, kys@microsoft.com, haiyangz@microsoft.com,
wei.liu@kernel.org, decui@microsoft.com,
linux-hyperv@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
In-Reply-To: <20250913192450.4134957-1-alok.a.tiwari@oracle.com>
From: Alok Tiwari <alok.a.tiwari@oracle.com> Sent: Saturday, September 13, 2025 12:25 PM
>
> The sysfs attributes out_read_index and out_write_index in
> vmbus_drv.c currently use %d to print outbound.current_read_index
> and outbound.current_write_index.
>
> These fields are u32 values, so printing them with %d (signed) is
> not logically correct. Update the format specifier to %u to
> correctly match their type.
>
> No functional change, only fixes the sysfs output format.
>
> Signed-off-by: Alok Tiwari <alok.a.tiwari@oracle.com>
> ---
> drivers/hv/vmbus_drv.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
> index 2ed5a1e89d69..8b58306cb140 100644
> --- a/drivers/hv/vmbus_drv.c
> +++ b/drivers/hv/vmbus_drv.c
> @@ -322,7 +322,7 @@ static ssize_t out_read_index_show(struct device *dev,
> &outbound);
> if (ret < 0)
> return ret;
> - return sysfs_emit(buf, "%d\n", outbound.current_read_index);
> + return sysfs_emit(buf, "%u\n", outbound.current_read_index);
> }
> static DEVICE_ATTR_RO(out_read_index);
>
> @@ -341,7 +341,7 @@ static ssize_t out_write_index_show(struct device *dev,
> &outbound);
> if (ret < 0)
> return ret;
> - return sysfs_emit(buf, "%d\n", outbound.current_write_index);
> + return sysfs_emit(buf, "%u\n", outbound.current_write_index);
> }
> static DEVICE_ATTR_RO(out_write_index);
>
> --
> 2.50.1
>
Reviewed-by: Michael Kelley <mhklinux@outlook.com>
^ permalink raw reply
* Re: [PATCH v2 01/21] x86/paravirt: Remove not needed includes of paravirt.h
From: kernel test robot @ 2025-09-18 3:18 UTC (permalink / raw)
To: Juergen Gross, linux-kernel, x86, linux-hyperv
Cc: llvm, oe-kbuild-all, Juergen Gross, Andy Lutomirski,
Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen,
H. Peter Anvin, K. Y. Srinivasan, Haiyang Zhang, Wei Liu,
Dexuan Cui, Peter Zijlstra, Will Deacon, Boqun Feng, Waiman Long,
Jiri Kosina, Josh Poimboeuf, Pawan Gupta, Boris Ostrovsky,
xen-devel
In-Reply-To: <20250917145220.31064-2-jgross@suse.com>
Hi Juergen,
kernel test robot noticed the following build errors:
[auto build test ERROR on tip/sched/core]
[also build test ERROR on kvm/queue kvm/next linus/master v6.17-rc6 next-20250917]
[cannot apply to tip/x86/core kvm/linux-next]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Juergen-Gross/x86-paravirt-Remove-not-needed-includes-of-paravirt-h/20250917-230321
base: tip/sched/core
patch link: https://lore.kernel.org/r/20250917145220.31064-2-jgross%40suse.com
patch subject: [PATCH v2 01/21] x86/paravirt: Remove not needed includes of paravirt.h
config: x86_64-allnoconfig (https://download.01.org/0day-ci/archive/20250918/202509181151.ja2As5H4-lkp@intel.com/config)
compiler: clang version 20.1.8 (https://github.com/llvm/llvm-project 87f0227cb60147a26a1eeb4fb06e3b505e9c7261)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250918/202509181151.ja2As5H4-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202509181151.ja2As5H4-lkp@intel.com/
All errors (new ones prefixed by >>):
In file included from kernel/cpu.c:13:
In file included from include/linux/sched/isolation.h:5:
In file included from include/linux/cpuset.h:18:
In file included from include/linux/mmu_context.h:5:
>> arch/x86/include/asm/mmu_context.h:225:2: error: call to undeclared function 'paravirt_enter_mmap'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
225 | paravirt_enter_mmap(mm);
| ^
>> arch/x86/include/asm/mmu_context.h:232:2: error: call to undeclared function 'paravirt_arch_exit_mmap'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
232 | paravirt_arch_exit_mmap(mm);
| ^
arch/x86/include/asm/mmu_context.h:232:2: note: did you mean 'ldt_arch_exit_mmap'?
arch/x86/include/asm/mmu_context.h:61:6: note: 'ldt_arch_exit_mmap' declared here
61 | void ldt_arch_exit_mmap(struct mm_struct *mm);
| ^
In file included from kernel/cpu.c:42:
In file included from include/trace/events/power.h:12:
In file included from include/linux/trace_events.h:10:
In file included from include/linux/perf_event.h:53:
In file included from include/linux/security.h:35:
In file included from include/linux/bpf.h:33:
In file included from arch/x86/include/asm/rqspinlock.h:5:
arch/x86/include/asm/paravirt.h:736:20: error: static declaration of 'paravirt_enter_mmap' follows non-static declaration
736 | static inline void paravirt_enter_mmap(struct mm_struct *mm)
| ^
arch/x86/include/asm/mmu_context.h:225:2: note: previous implicit declaration is here
225 | paravirt_enter_mmap(mm);
| ^
In file included from kernel/cpu.c:42:
In file included from include/trace/events/power.h:12:
In file included from include/linux/trace_events.h:10:
In file included from include/linux/perf_event.h:53:
In file included from include/linux/security.h:35:
In file included from include/linux/bpf.h:33:
In file included from arch/x86/include/asm/rqspinlock.h:5:
arch/x86/include/asm/paravirt.h:742:20: error: static declaration of 'paravirt_arch_exit_mmap' follows non-static declaration
742 | static inline void paravirt_arch_exit_mmap(struct mm_struct *mm)
| ^
arch/x86/include/asm/mmu_context.h:232:2: note: previous implicit declaration is here
232 | paravirt_arch_exit_mmap(mm);
| ^
4 errors generated.
--
In file included from kernel/workqueue.c:52:
In file included from include/linux/sched/isolation.h:5:
In file included from include/linux/cpuset.h:18:
In file included from include/linux/mmu_context.h:5:
>> arch/x86/include/asm/mmu_context.h:225:2: error: call to undeclared function 'paravirt_enter_mmap'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
225 | paravirt_enter_mmap(mm);
| ^
>> arch/x86/include/asm/mmu_context.h:232:2: error: call to undeclared function 'paravirt_arch_exit_mmap'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
232 | paravirt_arch_exit_mmap(mm);
| ^
arch/x86/include/asm/mmu_context.h:232:2: note: did you mean 'ldt_arch_exit_mmap'?
arch/x86/include/asm/mmu_context.h:61:6: note: 'ldt_arch_exit_mmap' declared here
61 | void ldt_arch_exit_mmap(struct mm_struct *mm);
| ^
2 errors generated.
--
>> arch/x86/kernel/x86_init.c:90:15: error: use of undeclared identifier 'default_banner'
90 | .banner = default_banner,
| ^
1 error generated.
--
In file included from arch/x86/mm/init.c:30:
>> arch/x86/include/asm/mmu_context.h:225:2: error: call to undeclared function 'paravirt_enter_mmap'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
225 | paravirt_enter_mmap(mm);
| ^
>> arch/x86/include/asm/mmu_context.h:232:2: error: call to undeclared function 'paravirt_arch_exit_mmap'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
232 | paravirt_arch_exit_mmap(mm);
| ^
arch/x86/include/asm/mmu_context.h:232:2: note: did you mean 'ldt_arch_exit_mmap'?
arch/x86/include/asm/mmu_context.h:61:6: note: 'ldt_arch_exit_mmap' declared here
61 | void ldt_arch_exit_mmap(struct mm_struct *mm);
| ^
>> arch/x86/mm/init.c:827:2: error: call to undeclared function 'paravirt_enter_mmap'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
827 | paravirt_enter_mmap(text_poke_mm);
| ^
3 errors generated.
vim +/paravirt_enter_mmap +225 arch/x86/include/asm/mmu_context.h
a31e184e4f6996 Dave Hansen 2019-01-02 221
c10e83f598d080 Thomas Gleixner 2017-12-14 222 static inline int arch_dup_mmap(struct mm_struct *oldmm, struct mm_struct *mm)
a1ea1c032b8f8c Dave Hansen 2014-11-18 223 {
a31e184e4f6996 Dave Hansen 2019-01-02 224 arch_dup_pkeys(oldmm, mm);
c9ae1b10d95610 Juergen Gross 2023-02-07 @225 paravirt_enter_mmap(mm);
82721d8b25d76c Kirill A. Shutemov 2023-03-12 226 dup_lam(oldmm, mm);
a4828f81037f49 Thomas Gleixner 2017-12-14 227 return ldt_dup_context(oldmm, mm);
a1ea1c032b8f8c Dave Hansen 2014-11-18 228 }
a1ea1c032b8f8c Dave Hansen 2014-11-18 229
a1ea1c032b8f8c Dave Hansen 2014-11-18 230 static inline void arch_exit_mmap(struct mm_struct *mm)
a1ea1c032b8f8c Dave Hansen 2014-11-18 231 {
a1ea1c032b8f8c Dave Hansen 2014-11-18 @232 paravirt_arch_exit_mmap(mm);
f55f0501cbf65e Andy Lutomirski 2017-12-12 233 ldt_arch_exit_mmap(mm);
a1ea1c032b8f8c Dave Hansen 2014-11-18 234 }
a1ea1c032b8f8c Dave Hansen 2014-11-18 235
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
^ permalink raw reply
* Re: [PATCH v2 21/21] x86/pvlocks: Move paravirt spinlock functions into own header
From: kernel test robot @ 2025-09-18 2:45 UTC (permalink / raw)
To: Juergen Gross, linux-kernel, x86, linux-hyperv, virtualization,
kvm
Cc: llvm, oe-kbuild-all, Juergen Gross, K. Y. Srinivasan,
Haiyang Zhang, Wei Liu, Dexuan Cui, Thomas Gleixner, Ingo Molnar,
Borislav Petkov, Dave Hansen, H. Peter Anvin, Ajay Kaher,
Alexey Makhalov, Broadcom internal kernel review list,
Paolo Bonzini, Vitaly Kuznetsov, Boris Ostrovsky, Josh Poimboeuf,
xen-devel
In-Reply-To: <20250917145220.31064-22-jgross@suse.com>
Hi Juergen,
kernel test robot noticed the following build warnings:
[auto build test WARNING on tip/sched/core]
[also build test WARNING on kvm/queue kvm/next linus/master v6.17-rc6 next-20250917]
[cannot apply to tip/x86/core kvm/linux-next]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Juergen-Gross/x86-paravirt-Remove-not-needed-includes-of-paravirt-h/20250917-230321
base: tip/sched/core
patch link: https://lore.kernel.org/r/20250917145220.31064-22-jgross%40suse.com
patch subject: [PATCH v2 21/21] x86/pvlocks: Move paravirt spinlock functions into own header
config: x86_64-randconfig-003-20250918 (https://download.01.org/0day-ci/archive/20250918/202509181008.MoLd2u4e-lkp@intel.com/config)
compiler: clang version 20.1.8 (https://github.com/llvm/llvm-project 87f0227cb60147a26a1eeb4fb06e3b505e9c7261)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250918/202509181008.MoLd2u4e-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202509181008.MoLd2u4e-lkp@intel.com/
All warnings (new ones prefixed by >>):
>> arch/x86/kernel/paravirt-spinlocks.c:13:13: warning: no previous prototype for function 'native_pv_lock_init' [-Wmissing-prototypes]
13 | void __init native_pv_lock_init(void)
| ^
arch/x86/kernel/paravirt-spinlocks.c:13:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
13 | void __init native_pv_lock_init(void)
| ^
| static
1 warning generated.
vim +/native_pv_lock_init +13 arch/x86/kernel/paravirt-spinlocks.c
12
> 13 void __init native_pv_lock_init(void)
14 {
15 if (boot_cpu_has(X86_FEATURE_HYPERVISOR))
16 static_branch_enable(&virt_spin_lock_key);
17 }
18
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
^ permalink raw reply
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