linux-kernel - Re: [PATCH] x86/hyperv: Fix undefined reference to isolation_type_en_snp without CONFIG

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] [day] [month] [year] [list]

Message-ID: <ZOWcSKlonRpbNloN@liuwe-devbox-debian-v2>
Date:   Wed, 23 Aug 2023 05:42:32 +0000
From:   Wei Liu <wei.liu@...nel.org>
To:     Dexuan Cui <decui@...rosoft.com>
Cc:     kys@...rosoft.com, haiyangz@...rosoft.com, wei.liu@...nel.org,
        linux-hyperv@...r.kernel.org, mikelley@...rosoft.com,
        tiala@...rosoft.com, tglx@...utronix.de, mingo@...hat.com,
        bp@...en8.de, dave.hansen@...ux.intel.com, hpa@...or.com,
        thomas.lendacky@....com, linux-kernel@...r.kernel.org,
        x86@...nel.org
Subject: Re: [PATCH] x86/hyperv: Fix undefined reference to
 isolation_type_en_snp without CONFIG_HYPERV

On Tue, Aug 22, 2023 at 08:20:08PM -0700, Dexuan Cui wrote:
> When CONFIG_HYPERV is not set, arch/x86/hyperv/ivm.c is not built (see
> arch/x86/Kbuild), so 'isolation_type_en_snp' in the ivm.c is not defined,
> and this failure happens:
> 
> ld: arch/x86/kernel/cpu/mshyperv.o: in function `ms_hyperv_init_platform':
> arch/x86/kernel/cpu/mshyperv.c:417: undefined reference to `isolation_type_en_snp'
> 
> Fix the failure by testing hv_get_isolation_type() and
> ms_hyperv.paravisor_present for a fully enlightened SNP VM: when
> CONFIG_HYPERV is not set, hv_get_isolation_type() is defined as a
> static inline function that always returns HV_ISOLATION_TYPE_NONE
> (see include/asm-generic/mshyperv.h), so the compiler won't generate any
> code for the ms_hyperv.paravisor_present and static_branch_enable().
> 
> Reported-by: Tom Lendacky <thomas.lendacky@....com>
> Closes: https://lore.kernel.org/lkml/b4979997-23b9-0c43-574e-e4a3506500ff@amd.com/
> Fixes: d6e2d6524437 ("x86/hyperv: Add sev-snp enlightened guest static key")
> Signed-off-by: Dexuan Cui <decui@...rosoft.com>

Applied. Thanks.