From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AIpwx49CZcBYU1Iuqgipvw7k+FzjlNKnHww3RBL/1ts15zkdn2/HGZqTBhd09rCuMmwI78P5zi89 ARC-Seal: i=1; a=rsa-sha256; t=1524652489; cv=none; d=google.com; s=arc-20160816; b=mRhISOG1Fw3zkcQ0Mkj9SbufcRShViQxxInxkkvCB7PEjN5WQVWHuwhJfMNHFr3Anj rWlcOudbLaaYm4nN+AMRd3emcqs0H2yNKFU+H69RxfUt+DYC2DurgRE7dI6MeETRoFwF 0Ch/40DAuSy4erz/LvpgZHuEg8LT4Jyq9zCXSyCZ6tGSx6Auv2fr0eq6YJJq96pLPJni JCKLOlKeSfDH7msjoqdi0xEHjHYmBva9HiZYF3ogu4/LdN1BAX1nMnBJp1i2hhYGD85A lKurm/GWDzd7ZGj+BAyBspuM2gU6nMRzwqnLQL7MkLkA+Q0K21HEsNWNedCMuQarkSfs iCwg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=mime-version:user-agent:references:in-reply-to:message-id:date :subject:cc:to:from:arc-authentication-results; bh=uHkUBf8FUuT2NF7KfrJTnttQ6iTmUqWVIIAs0nyBGUc=; b=Z0ueZ6nywz0M21ycQbXzT3vY0Cn0ff4WCV+y0E6w8tK7UgrVutDAOCkjM+7SbQ8iF4 77eOzf1ueqTlNYzYstWWLS5HCuu8thHuEq93B58VV/1qNkGY/PIUaO+WqznJJQHAQS/b ubpIe4a7aJwnokq2ULtSu1MIKirqE9DXwj/bZ+Bxx7nhHZyTl1r40jZvbMG6kIQ1jEXb cctGvkpb++k5MYF3EgYVVwJ+wnyqlp0bp+s60FOD+tIU6c2YehY6LDK7/BUv/IHPENBT NAMls0VbBX+LoJe3ZT7L3Aa2gGo6QynELW5RX+NGgzt7eCKKUCVeoxAOpc3ORl8TYrev cEVw== ARC-Authentication-Results: i=1; mx.google.com; spf=softfail (google.com: domain of transitioning gregkh@linuxfoundation.org does not designate 90.92.61.202 as permitted sender) smtp.mailfrom=gregkh@linuxfoundation.org Authentication-Results: mx.google.com; spf=softfail (google.com: domain of transitioning gregkh@linuxfoundation.org does not designate 90.92.61.202 as permitted sender) smtp.mailfrom=gregkh@linuxfoundation.org From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Li RongQing , Dou Liyang , Thomas Gleixner , len.brown@intel.com, rjw@rjwysocki.net, hpa@zytor.com Subject: [PATCH 4.16 05/26] x86/acpi: Prevent X2APIC id 0xffffffff from being accounted Date: Wed, 25 Apr 2018 12:33:14 +0200 Message-Id: <20180425103315.066212043@linuxfoundation.org> X-Mailer: git-send-email 2.17.0 In-Reply-To: <20180425103314.842517924@linuxfoundation.org> References: <20180425103314.842517924@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-LABELS: =?utf-8?b?IlxcU2VudCI=?= X-GMAIL-THRID: =?utf-8?q?1598714008873364541?= X-GMAIL-MSGID: =?utf-8?q?1598714008873364541?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.16-stable review patch. If anyone has any objections, please let me know. ------------------ From: Dou Liyang commit 10daf10ab154e31237a8c07242be3063fb6a9bf4 upstream. RongQing reported that there are some X2APIC id 0xffffffff in his machine's ACPI MADT table, which makes the number of possible CPU inaccurate. The reason is that the ACPI X2APIC parser has no sanity check for APIC ID 0xffffffff, which is an invalid id in all APIC types. See "Intel® 64 Architecture x2APIC Specification", Chapter 2.4.1. Add a sanity check to acpi_parse_x2apic() which ignores the invalid id. Reported-by: Li RongQing Signed-off-by: Dou Liyang Signed-off-by: Thomas Gleixner Cc: stable@vger.kernel.org Cc: len.brown@intel.com Cc: rjw@rjwysocki.net Cc: hpa@zytor.com Link: https://lkml.kernel.org/r/20180412014052.25186-1-douly.fnst@cn.fujitsu.com Signed-off-by: Greg Kroah-Hartman --- arch/x86/kernel/acpi/boot.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/arch/x86/kernel/acpi/boot.c +++ b/arch/x86/kernel/acpi/boot.c @@ -215,6 +215,10 @@ acpi_parse_x2apic(struct acpi_subtable_h apic_id = processor->local_apic_id; enabled = processor->lapic_flags & ACPI_MADT_ENABLED; + /* Ignore invalid ID */ + if (apic_id == 0xffffffff) + return 0; + /* * We need to register disabled CPU as well to permit * counting disabled CPUs. This allows us to size