From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ozlabs.org (bilbo.ozlabs.org [203.11.71.1]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 40ydkZ5DkDzF0tP for ; Sat, 2 Jun 2018 21:09:26 +1000 (AEST) From: Michael Ellerman To: gregkh@linuxfoundation.org Cc: stable@vger.kernel.org, linuxppc-dev@ozlabs.org Subject: [PATCH stable 4.9 14/23] powerpc/64s: Enhance the information in cpu_show_meltdown() Date: Sat, 2 Jun 2018 21:08:59 +1000 Message-Id: <20180602110908.29773-15-mpe@ellerman.id.au> In-Reply-To: <20180602110908.29773-1-mpe@ellerman.id.au> References: <20180602110908.29773-1-mpe@ellerman.id.au> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , commit ff348355e9c72493947be337bb4fae4fc1a41eba upstream. Now that we have the security feature flags we can make the information displayed in the "meltdown" file more informative. Signed-off-by: Michael Ellerman --- arch/powerpc/kernel/security.c | 30 ++++++++++++++++++++++++++++-- 1 file changed, 28 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/kernel/security.c b/arch/powerpc/kernel/security.c index 564e7f182a16..865db6f8bcca 100644 --- a/arch/powerpc/kernel/security.c +++ b/arch/powerpc/kernel/security.c @@ -6,6 +6,7 @@ #include #include +#include #include @@ -19,8 +20,33 @@ unsigned long powerpc_security_features __read_mostly = \ ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr, char *buf) { - if (rfi_flush) - return sprintf(buf, "Mitigation: RFI Flush\n"); + bool thread_priv; + + thread_priv = security_ftr_enabled(SEC_FTR_L1D_THREAD_PRIV); + + if (rfi_flush || thread_priv) { + struct seq_buf s; + seq_buf_init(&s, buf, PAGE_SIZE - 1); + + seq_buf_printf(&s, "Mitigation: "); + + if (rfi_flush) + seq_buf_printf(&s, "RFI Flush"); + + if (rfi_flush && thread_priv) + seq_buf_printf(&s, ", "); + + if (thread_priv) + seq_buf_printf(&s, "L1D private per thread"); + + seq_buf_printf(&s, "\n"); + + return s.len; + } + + if (!security_ftr_enabled(SEC_FTR_L1D_FLUSH_HV) && + !security_ftr_enabled(SEC_FTR_L1D_FLUSH_PR)) + return sprintf(buf, "Not affected\n"); return sprintf(buf, "Vulnerable\n"); } -- 2.14.1