linux-kernel - Re: [PATCH v3 0/6] Hyper-V: Implement hypervisor core collection

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

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <74e019ac-afc7-3178-0f0a-dc903af5c4ca@linux.microsoft.com>
Date: Fri, 17 Oct 2025 16:58:24 -0700
From: Mukesh R <mrathor@...ux.microsoft.com>
To: Wei Liu <wei.liu@...nel.org>
Cc: linux-hyperv@...r.kernel.org, linux-kernel@...r.kernel.org,
 linux-arch@...r.kernel.org, kys@...rosoft.com, haiyangz@...rosoft.com,
 decui@...rosoft.com, tglx@...utronix.de, mingo@...hat.com, bp@...en8.de,
 dave.hansen@...ux.intel.com, x86@...nel.org, hpa@...or.com, arnd@...db.de
Subject: Re: [PATCH v3 0/6] Hyper-V: Implement hypervisor core collection

On 10/17/25 15:57, Wei Liu wrote:
> On Fri, Oct 17, 2025 at 10:33:00PM +0000, Wei Liu wrote:
>> On Mon, Oct 06, 2025 at 03:42:02PM -0700, Mukesh Rathor wrote:
>> [...]
>>> Mukesh Rathor (6):
>>>   x86/hyperv: Rename guest crash shutdown function
>>>   hyperv: Add two new hypercall numbers to guest ABI public header
>>>   hyperv: Add definitions for hypervisor crash dump support
>>>   x86/hyperv: Add trampoline asm code to transition from hypervisor
>>>   x86/hyperv: Implement hypervisor RAM collection into vmcore
>>>   x86/hyperv: Enable build of hypervisor crashdump collection files
>>>
>>
>> Applied to hyperv-next. Thanks.
> 
> This breaks i386 build.
> 
> /work/linux-on-hyperv/linux.git/arch/x86/hyperv/hv_init.c: In function ?hyperv_init?:
> /work/linux-on-hyperv/linux.git/arch/x86/hyperv/hv_init.c:557:17: error: implicit declaration of function ?hv_root_crash_init? [-Werror=implicit-function-declaration]
>   557 |                 hv_root_crash_init();
>       |                 ^~~~~~~~~~~~~~~~~~
> 
> That's because CONFIG_MSHV_ROOT is only available on x86_64. And the
> crash feature is guarded by CONFIG_MSHV_ROOT.
> 
> Applying the following diff fixes the build.


Thanks. A bit surprising tho that CONFIG_MSHV_ROOT doesn't have 
hard dependency on x86_64. It should, no?

Thanks,
-Mukesh


> diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c
> index e28737ec7054..c1300339d2eb 100644
> --- a/arch/x86/hyperv/hv_init.c
> +++ b/arch/x86/hyperv/hv_init.c
> @@ -554,7 +554,9 @@ void __init hyperv_init(void)
>                 memunmap(src);
> 
>                 hv_remap_tsc_clocksource();
> +#ifdef CONFIG_X86_64
>                 hv_root_crash_init();
> +#endif
>         } else {
>                 hypercall_msr.guest_physical_address = vmalloc_to_pfn(hv_hypercall_pg);
>                 wrmsrq(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
> 
>>
>>>  arch/x86/hyperv/Makefile        |   6 +
>>>  arch/x86/hyperv/hv_crash.c      | 642 ++++++++++++++++++++++++++++++++
>>>  arch/x86/hyperv/hv_init.c       |   1 +
>>>  arch/x86/hyperv/hv_trampoline.S | 101 +++++
>>>  arch/x86/include/asm/mshyperv.h |  13 +
>>>  arch/x86/kernel/cpu/mshyperv.c  |   5 +-
>>>  include/hyperv/hvgdk_mini.h     |   2 +
>>>  include/hyperv/hvhdk_mini.h     |  55 +++
>>>  8 files changed, 823 insertions(+), 2 deletions(-)
>>>  create mode 100644 arch/x86/hyperv/hv_crash.c
>>>  create mode 100644 arch/x86/hyperv/hv_trampoline.S
>>>
>>> -- 
>>> 2.36.1.vfs.0.0
>>>