From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AH8x226seVDX993zlC1nfQl3kAjKuWJP7W2aCoRpskU877zRbXwQ1ATcEwTXq0/hekkbSoA3fh6j ARC-Seal: i=1; a=rsa-sha256; t=1516924421; cv=none; d=google.com; s=arc-20160816; b=O9qITomH+ErWMz3+BozU3IA6RuxDk/LTYGlHIDN/RuULuolej0moH6lUpM4rBAcOcx X7fRZ+gD9cXsOWb1J8+xV9NcdneCqwZODF3gbPt2/7jDew1esZgLRRe+7F+TyYlRyKRH +TqjFG5MfCsN4pQX/wyb7b3qxP5u4pXBtAI7JvCp25FOnSnbgiVXywGBeuQvYhFxSvUH ZZaIa8bRAaZTgBbkVR/qokBHAQvg88p03wdSizY6hE8jCXKCsZzwS/v8cO+Qxt+n+UCw RbZHfMLVIhZxFWKaRNNaJa+J41jbHSEnwejA3J2J7BC10/qEyOT6+/HFEmFJU+fLMFWW Hteg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=content-transfer-encoding:content-language:in-reply-to:mime-version :user-agent:date:message-id:from:references:cc:to:subject :dkim-signature:arc-authentication-results; bh=Eb9pUcGd+72wOvUJCerjKmNSzGNkN2FUxZk0UOYXf9M=; b=yJHHvU0r2mga7QHTUf8ncNjjPMkOo1M4+OPkLpSBzS8ov0zlWLogoIBx8j3Nkt4hQE I/IxUaFbRRB6j9MsMtOBb4M8YVYoP53mdRKhf1QcnV7JHk6A0ZE4BFJBTWr8OnPKDVq3 FlkH/PNBx/EkqOKbDhaIBgjNHRtYhWU8m3s4HL4LiTgsC7iytHp8LiulUn7JX75/gjzb ZW/4R3X18IiRMnhiBWqv3A0bg0fv2tNPe9xQrLgWIp8ym2hMsYcecAuOpvsC3+8VsAAo zjU+efPXQm7k3ZE9AIbedQXuTED79Z4FkbKQ1I4om5KR7aghW61qU3iyvBxlzrSzJDTS 5SEw== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@infradead.org header.s=bombadil.20170209 header.b=hj7MlLfa; spf=pass (google.com: best guess record for domain of rdunlap@infradead.org designates 65.50.211.133 as permitted sender) smtp.mailfrom=rdunlap@infradead.org Authentication-Results: mx.google.com; dkim=pass header.i=@infradead.org header.s=bombadil.20170209 header.b=hj7MlLfa; spf=pass (google.com: best guess record for domain of rdunlap@infradead.org designates 65.50.211.133 as permitted sender) smtp.mailfrom=rdunlap@infradead.org Subject: Re: [PATCH v4] retpoline/module: Warn for missing retpoline in module To: Andi Kleen , tglx@linutronix.de Cc: gregkh@linuxfoundation.org, dwmw@amazon.co.uk, linux-kernel@vger.kernel.org, torvalds@linux-foundation.org, x86@kernel.org, arjan@linux.intel.com, Andi Kleen , jeyu@kernel.org References: <20180125235028.31211-1-andi@firstfloor.org> From: Randy Dunlap Message-ID: Date: Thu, 25 Jan 2018 15:53:36 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.3.0 MIME-Version: 1.0 In-Reply-To: <20180125235028.31211-1-andi@firstfloor.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: =?utf-8?q?1590610357649100474?= X-GMAIL-MSGID: =?utf-8?q?1590610541542958613?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: On 01/25/2018 03:50 PM, Andi Kleen wrote: > diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c > index 390b3dc3d438..8766e13efe80 100644 > --- a/arch/x86/kernel/cpu/bugs.c > +++ b/arch/x86/kernel/cpu/bugs.c > @@ -11,6 +11,7 @@ > #include > #include > #include > +#include > > #include > #include > @@ -94,6 +95,20 @@ static const char *spectre_v2_strings[] = { > > static enum spectre_v2_mitigation spectre_v2_enabled = SPECTRE_V2_NONE; > > +static bool spectre_v2_bad_module; > + > +#ifdef RETPOLINE > +bool retpoline_module_ok(bool has_retpoline) > +{ > + if (spectre_v2_enabled == SPECTRE_V2_NONE || has_retpoline) > + return true; > + > + pr_err("system may be vunerable to spectre_v2\n"); vulnerable > + spectre_v2_bad_module = true; > + return false; > +} > +#endif > + > static void __init spec2_print_if_insecure(const char *reason) > { > if (boot_cpu_has_bug(X86_BUG_SPECTRE_V2)) > @@ -278,6 +293,7 @@ ssize_t cpu_show_spectre_v2(struct device *dev, > if (!boot_cpu_has_bug(X86_BUG_SPECTRE_V2)) > return sprintf(buf, "Not affected\n"); > > - return sprintf(buf, "%s\n", spectre_v2_strings[spectre_v2_enabled]); > + return sprintf(buf, "%s%s\n", spectre_v2_strings[spectre_v2_enabled], > + spectre_v2_bad_module ? " but vulnerable module loaded" : ""); > } > #endif -- ~Randy