RE: [PATCH v1 6/6] x86/hyperv: Enable build of hypervisor crashdump collection files

Michael Kelley
2025-09-15T17:56:16Z

From: Mukesh Rathor <mrathor@linux.microsoft.com> Sent: Tuesday, September 9, 2025 5:10 PM
>
> Enable build of the new files introduced in the earlier commits and add
> call to do the setup during boot.
>
> Signed-off-by: Mukesh Rathor <mrathor@linux.microsoft.com>
> ---
> arch/x86/hyperv/Makefile | 6 ++++++
> arch/x86/hyperv/hv_init.c | 1 +
> include/asm-generic/mshyperv.h | 9 +++++++++
> 3 files changed, 16 insertions(+)
>
> diff --git a/arch/x86/hyperv/Makefile b/arch/x86/hyperv/Makefile
> index d55f494f471d..6f5d97cddd80 100644
> --- a/arch/x86/hyperv/Makefile
> +++ b/arch/x86/hyperv/Makefile
> @@ -5,4 +5,10 @@ obj-$(CONFIG_HYPERV_VTL_MODE) += hv_vtl.o
>
> ifdef CONFIG_X86_64
> obj-$(CONFIG_PARAVIRT_SPINLOCKS) += hv_spinlock.o
> +
> + ifdef CONFIG_MSHV_ROOT
> + CFLAGS_REMOVE_hv_trampoline.o += -pg
> + CFLAGS_hv_trampoline.o += -fno-stack-protector
> + obj-$(CONFIG_CRASH_DUMP) += hv_crash.o hv_trampoline.o
> + endif
> endif
> diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c
> index afdbda2dd7b7..577bbd143527 100644
> --- a/arch/x86/hyperv/hv_init.c
> +++ b/arch/x86/hyperv/hv_init.c
> @@ -510,6 +510,7 @@ void __init hyperv_init(void)
> memunmap(src);
>
> hv_remap_tsc_clocksource();
> + hv_root_crash_init();
> } else {
> hypercall_msr.guest_physical_address = vmalloc_to_pfn(hv_hypercall_pg);
> wrmsrq(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
> diff --git a/include/asm-generic/mshyperv.h b/include/asm-generic/mshyperv.h
> index dbd4c2f3aee3..952c221765f5 100644
> --- a/include/asm-generic/mshyperv.h
> +++ b/include/asm-generic/mshyperv.h
> @@ -367,6 +367,15 @@ int hv_call_deposit_pages(int node, u64 partition_id, u32
> num_pages);
> int hv_call_add_logical_proc(int node, u32 lp_index, u32 acpi_id);
> int hv_call_create_vp(int node, u64 partition_id, u32 vp_index, u32 flags);
>
> +#if CONFIG_CRASH_DUMP
> +void hv_root_crash_init(void);
> +void hv_crash_asm32(void);
> +void hv_crash_asm64_lbl(void);
> +void hv_crash_asm_end(void);
> +#else /* CONFIG_CRASH_DUMP */
> +static inline void hv_root_crash_init(void) {}
> +#endif /* CONFIG_CRASH_DUMP */
> +

The hv_crash_asm* functions are x86 specific. Seems like their
declarations should go in arch/x86/include/asm/mshyperv.h, not in
the architecture-neutral include/asm-generic/mshyperv.h.

> #else /* CONFIG_MSHV_ROOT */
> static inline bool hv_root_partition(void) { return false; }
> static inline bool hv_l1vh_partition(void) { return false; }
> --
> 2.36.1.vfs.0.0
>