From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9C8E6639 for ; Fri, 22 Sep 2023 04:58:46 +0000 (UTC) Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 6629B192; Thu, 21 Sep 2023 21:58:45 -0700 (PDT) Received: from linuxonhyperv3.guj3yctzbm1etfxqx2vob5hsef.xx.internal.cloudapp.net (linux.microsoft.com [13.77.154.182]) by linux.microsoft.com (Postfix) with ESMTPSA id A1BED212C5B7; Thu, 21 Sep 2023 21:58:44 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com A1BED212C5B7 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1695358724; bh=+yXMZYNsMsvn2jwwDbQl1ZwR5DmyfHWdhUieAsjjntE=; h=From:To:Cc:Subject:Date:From; b=ZV8FpA5rQIGeeqhPqT4DBWcgP+m3qnVc4ZFfXauyHrMtr98EOzQ1wYPpgAl/NxFTM cM2GWtz3RpyVULVnoqz0MAQ0g/yv/US4sVIPpE0Zc4+te1K+nhtiCi+dzHqQt/xz8d +QyjT7tMhmkicZfXAlaVkFiDXVJBwFShF4dWdjOM= From: Saurabh Sengar To: kys@microsoft.com, haiyangz@microsoft.com, wei.liu@kernel.org, decui@microsoft.com, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org, mikelley@microsoft.com Cc: minipli@grsecurity.net, ssengar@microsoft.com Subject: [PATCH v2] x86/hyperv: Remove hv_vtl_early_init initcall Date: Thu, 21 Sep 2023 21:58:40 -0700 Message-Id: <1695358720-27681-1-git-send-email-ssengar@linux.microsoft.com> X-Mailer: git-send-email 1.8.3.1 X-Spam-Status: No, score=-17.5 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,ENV_AND_HDR_SPF_MATCH,RCVD_IN_DNSWL_BLOCKED, SPF_HELO_PASS,SPF_PASS,USER_IN_DEF_DKIM_WL,USER_IN_DEF_SPF_WL autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk X-Mailing-List: linux-hyperv@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: There has been cases reported where HYPERV_VTL_MODE is enabled by mistake, on a non Hyper-V platforms. This causes the hv_vtl_early_init function to be called in an non Hyper-V/VTL platforms which results the memory corruption. Remove the early_initcall for hv_vtl_early_init and call it at the end of hyperv_init to make sure it is never called in a non Hyper-V platform by mistake. Reported-by: Mathias Krause Closes: https://lore.kernel.org/lkml/40467722-f4ab-19a5-4989-308225b1f9f0@grsecurity.net/ Signed-off-by: Saurabh Sengar Acked-by: Mathias Krause --- This patch is dependent on : https://lore.kernel.org/lkml/1695182675-13405-1-git-send-email-ssengar@linux.microsoft.com/ [V2] - Fix HYPERV_VTL_MODE=n compilation flow - Updated commit s/vhv_vtl_early_init/hv_vtl_early_init arch/x86/hyperv/hv_init.c | 3 +++ arch/x86/hyperv/hv_vtl.c | 3 +-- arch/x86/include/asm/mshyperv.h | 2 ++ 3 files changed, 6 insertions(+), 2 deletions(-) diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c index f0128fd4031d..608f4fe41fb7 100644 --- a/arch/x86/hyperv/hv_init.c +++ b/arch/x86/hyperv/hv_init.c @@ -610,6 +610,9 @@ void __init hyperv_init(void) /* Find the VTL */ ms_hyperv.vtl = get_vtl(); + if (ms_hyperv.vtl > 0) /* non default VTL */ + hv_vtl_early_init(); + return; clean_guest_os_id: diff --git a/arch/x86/hyperv/hv_vtl.c b/arch/x86/hyperv/hv_vtl.c index 36a562218010..999f5ac82fe9 100644 --- a/arch/x86/hyperv/hv_vtl.c +++ b/arch/x86/hyperv/hv_vtl.c @@ -215,7 +215,7 @@ static int hv_vtl_wakeup_secondary_cpu(int apicid, unsigned long start_eip) return hv_vtl_bringup_vcpu(vp_id, start_eip); } -static int __init hv_vtl_early_init(void) +int __init hv_vtl_early_init(void) { /* * `boot_cpu_has` returns the runtime feature support, @@ -230,4 +230,3 @@ static int __init hv_vtl_early_init(void) return 0; } -early_initcall(hv_vtl_early_init); diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h index 033b53f993c6..896445edc6a8 100644 --- a/arch/x86/include/asm/mshyperv.h +++ b/arch/x86/include/asm/mshyperv.h @@ -340,8 +340,10 @@ static inline u64 hv_get_non_nested_register(unsigned int reg) { return 0; } #ifdef CONFIG_HYPERV_VTL_MODE void __init hv_vtl_init_platform(void); +int __init hv_vtl_early_init(void); #else static inline void __init hv_vtl_init_platform(void) {} +static inline int __init hv_vtl_early_init(void) { return 0; } #endif #include -- 2.34.1