From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 44FCBAD23 for ; Thu, 27 Oct 2022 17:03:24 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id BEEE1C433C1; Thu, 27 Oct 2022 17:03:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1666890204; bh=MSz3EoNrxWMXoDEjg1U8CjrEvkFOhN38JE/lTI0s24k=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=DJoWOxkpQcvl0wyWCyrkWxTPblt/aW+7SnpTLhEf4PAUAAIcaU7KxrLlLsCPMou9q 6P2mzZYEOZrCtcRkDZbT19HyHfiZ9iRY7bcogZnp5dtW6WSBIbFNOdXUHaCbuK0v57 9W8c5yOg6f4ConX8ryui8fZuzuaVyMuXN0Wr4z1c= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Len Brown , Zhang Rui , Dave Hansen Subject: [PATCH 5.15 31/79] x86/topology: Fix duplicated core ID within a package Date: Thu, 27 Oct 2022 18:55:29 +0200 Message-Id: <20221027165055.987750101@linuxfoundation.org> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221027165054.917467648@linuxfoundation.org> References: <20221027165054.917467648@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Zhang Rui commit 71eac7063698b7d7b8fafb1683ac24a034541141 upstream. Today, core ID is assumed to be unique within each package. But an AlderLake-N platform adds a Module level between core and package, Linux excludes the unknown modules bits from the core ID, resulting in duplicate core ID's. To keep core ID unique within a package, Linux must include all APIC-ID bits for known or unknown levels above the core and below the package in the core ID. It is important to understand that core ID's have always come directly from the APIC-ID encoding, which comes from the BIOS. Thus there is no guarantee that they start at 0, or that they are contiguous. As such, naively using them for array indexes can be problematic. [ dhansen: un-known -> unknown ] Fixes: 7745f03eb395 ("x86/topology: Add CPUID.1F multi-die/package support") Suggested-by: Len Brown Signed-off-by: Zhang Rui Signed-off-by: Dave Hansen Reviewed-by: Len Brown Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20221014090147.1836-5-rui.zhang@intel.com Signed-off-by: Greg Kroah-Hartman --- arch/x86/kernel/cpu/topology.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/arch/x86/kernel/cpu/topology.c +++ b/arch/x86/kernel/cpu/topology.c @@ -141,7 +141,7 @@ int detect_extended_topology(struct cpui sub_index++; } - core_select_mask = (~(-1 << core_plus_mask_width)) >> ht_mask_width; + core_select_mask = (~(-1 << pkg_mask_width)) >> ht_mask_width; die_select_mask = (~(-1 << die_plus_mask_width)) >> core_plus_mask_width;