From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 19D0A2701AE; Fri, 25 Apr 2025 16:43:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=13.77.154.182 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745599405; cv=none; b=UskSIRU2bmUwjQoyZv2yU+gznbHN6Tq6jiAZiahPI48kpeFBipCyAtIMHWv4mngySdRVG6L0RCMA6dVMcKz6RdzfVgVvuDEr1MGOZKaWltt9ctXOvcld+d8kJQLD9lEoP6HDuTTXoJzo0Lp4FibY3xYY69vz8lPSQqQDOefCdGM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745599405; c=relaxed/simple; bh=0nePQQ4XmdqqCGIis7u2dnLV8W89M2J3s8kLeJCuzaE=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=DqfzojX1CLVuZa+klXelhJo0CXAQMjrzPaLmNjVhyF/UEo58GODKpPNGJ5+FgZT3TnFMYaVfVMyI4WnGYfFww3CtNtWxBPAuCN9/e4P3S2aPb2qMAqRXFOF+jw1Vqm/jX+PSgxqSvGxWtkJUH+/3+X3p33VXmKkgSdPSQPUwqJg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com; spf=pass smtp.mailfrom=linux.microsoft.com; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b=e2Isvt01; arc=none smtp.client-ip=13.77.154.182 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b="e2Isvt01" Received: from [10.16.80.157] (unknown [131.107.147.157]) by linux.microsoft.com (Postfix) with ESMTPSA id 7E5892020940; Fri, 25 Apr 2025 09:43:22 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 7E5892020940 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1745599402; bh=64nT0dPAvYSJyGupR1SMj+3koyYcXK23DHHScnd/PAk=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=e2Isvt01azY9WJAx8bfWpapo8WSaB2WQQQ/xEZdq7O/VdvqEc/z5gG1gjwlvOZmMj PCpGUnuKUAFlcpOg3KnIOOzbEUrAJVpASM1M+8umVCCL+D1J0LVDkCLQd7FPRoquni uRmPiuQAFsQr4uB1+h3vmjYCxPPUDeKyFntwefps= Message-ID: <8fa1045a-c3e9-48e0-86fe-ab554d7475c8@linux.microsoft.com> Date: Fri, 25 Apr 2025 09:43:22 -0700 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [EXTERNAL] Re: [PATCH hyperv-next] x86/hyperv: Fix APIC ID and VP ID confusion in hv_snp_boot_ap() To: Saurabh Singh Sengar , Wei Liu Cc: "bp@alien8.de" , "dave.hansen@linux.intel.com" , Dexuan Cui , Haiyang Zhang , "hpa@zytor.com" , KY Srinivasan , "mikelley@microsoft.com" , "mingo@redhat.com" , "tglx@linutronix.de" , Tianyu Lan , "linux-hyperv@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "x86@kernel.org" , Allen Pais , Ben Hillis , Brian Perkins , Sunil Muthuswamy References: <20250424215746.467281-1-romank@linux.microsoft.com> Content-Language: en-US From: Roman Kisel In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 4/25/2025 2:14 AM, Saurabh Singh Sengar wrote: >> >> On Thu, Apr 24, 2025 at 02:57:46PM -0700, Roman Kisel wrote: >>> To start an application processor in SNP-isolated guest, a hypercall >>> is used that takes a virtual processor index. The hv_snp_boot_ap() >>> function uses that START_VP hypercall but passes as VP ID to it what >>> it receives as a wakeup_secondary_cpu_64 callback: the APIC ID. >>> >>> As those two aren't generally interchangeable, that may lead to hung >>> APs if VP IDs and APIC IDs don't match, e.g. APIC IDs might be sparse >>> whereas VP IDs never are. >>> >>> Update the parameter names to avoid confusion as to what the parameter >>> is. Use the APIC ID to VP ID conversion to provide correct input to >>> the hypercall. >>> >>> Cc: stable@vger.kernel.org >>> Fixes: 44676bb9d566 ("x86/hyperv: Add smp support for SEV-SNP guest") >>> Signed-off-by: Roman Kisel >> >> Applied to hyperv-fixes. > > This patch will break the builds. > > Roman, > Have you tested this patch on the latest linux-next ? Thanks for your help! Only on hyperv-next, looking how to repro and fix on linux-next. The kernel robot was happy, or I am missing some context about how the robot works... What was your kernel configuration, or just anything that enables Hyper-V? I thought the the linux-next tree would be a subset of hyper-next so should work, realizing that have to check, likely there might be changes from other trees. > > Regards, > Saurabh > -- Thank you, Roman