Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751944AbaBTJcP (ORCPT ); Thu, 20 Feb 2014 04:32:15 -0500 Received: from mail.skyhub.de ([78.46.96.112]:43599 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751002AbaBTJcL (ORCPT ); Thu, 20 Feb 2014 04:32:11 -0500 Date: Thu, 20 Feb 2014 10:32:08 +0100 From: Borislav Petkov To: Aravind Gopalakrishnan Cc: dougthompson@xmission.com, linux-edac@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] EDAC, MCE, AMD: Fix code to prevent NULL dereference Message-ID: <20140220093207.GB8876@pd.tnic> References: <1392659391-2411-1-git-send-email-Aravind.Gopalakrishnan@amd.com> <20140217182729.GE4559@pd.tnic> <5302625C.4050700@amd.com> <20140217194153.GG4559@pd.tnic> <53028EE8.20106@amd.com> <20140218003654.GK4559@pd.tnic> <20140218084636.GA24465@pd.tnic> <5303A607.7090309@amd.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <5303A607.7090309@amd.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Feb 18, 2014 at 12:27:19PM -0600, Aravind Gopalakrishnan wrote: > This works. But a drawback is that you wouldn't get the output from > more generic error decoding that happens after the 'switch' in > amd_decode_mce: > > pr_emerg(HW_ERR "Error Status: %s\n", decode_error_status(m)) > (etc..) (etc..) > amd_decode_err_code(m->status & 0xffff); > > A quick fix for this is to rearrange the above chunk of code to > happen before the 'switch' Is that better (I also dropped the "Error Status: " prefix because it is not needed): - [ 46.822828] [Hardware Error]: Error Status: Uncorrected, software containable error. + [ 46.822828] [Hardware Error]: Uncorrected, software containable error. -- diff --git a/drivers/edac/mce_amd.c b/drivers/edac/mce_amd.c index 30f7309446a6..528b0c4998d9 100644 --- a/drivers/edac/mce_amd.c +++ b/drivers/edac/mce_amd.c @@ -741,6 +741,36 @@ int amd_decode_mce(struct notifier_block *nb, unsigned long val, void *data) if (amd_filter_mce(m)) return NOTIFY_STOP; + pr_emerg(HW_ERR "%s\n", decode_error_status(m)); + + pr_emerg(HW_ERR "CPU:%d (%x:%x:%x) MC%d_STATUS[%s|%s|%s|%s|%s", + m->extcpu, + c->x86, c->x86_model, c->x86_mask, + m->bank, + ((m->status & MCI_STATUS_OVER) ? "Over" : "-"), + ((m->status & MCI_STATUS_UC) ? "UE" : "CE"), + ((m->status & MCI_STATUS_MISCV) ? "MiscV" : "-"), + ((m->status & MCI_STATUS_PCC) ? "PCC" : "-"), + ((m->status & MCI_STATUS_ADDRV) ? "AddrV" : "-")); + + if (c->x86 == 0x15 || c->x86 == 0x16) + pr_cont("|%s|%s", + ((m->status & MCI_STATUS_DEFERRED) ? "Deferred" : "-"), + ((m->status & MCI_STATUS_POISON) ? "Poison" : "-")); + + /* do the two bits[14:13] together */ + ecc = (m->status >> 45) & 0x3; + if (ecc) + pr_cont("|%sECC", ((ecc == 2) ? "C" : "U")); + + pr_cont("]: 0x%016llx\n", m->status); + + if (m->status & MCI_STATUS_ADDRV) + pr_emerg(HW_ERR "MC%d_ADDR: 0x%016llx\n", m->bank, m->addr); + + if (!fam_ops) + goto err_code; + switch (m->bank) { case 0: decode_mc0_mce(m); @@ -774,33 +804,7 @@ int amd_decode_mce(struct notifier_block *nb, unsigned long val, void *data) break; } - pr_emerg(HW_ERR "Error Status: %s\n", decode_error_status(m)); - - pr_emerg(HW_ERR "CPU:%d (%x:%x:%x) MC%d_STATUS[%s|%s|%s|%s|%s", - m->extcpu, - c->x86, c->x86_model, c->x86_mask, - m->bank, - ((m->status & MCI_STATUS_OVER) ? "Over" : "-"), - ((m->status & MCI_STATUS_UC) ? "UE" : "CE"), - ((m->status & MCI_STATUS_MISCV) ? "MiscV" : "-"), - ((m->status & MCI_STATUS_PCC) ? "PCC" : "-"), - ((m->status & MCI_STATUS_ADDRV) ? "AddrV" : "-")); - - if (c->x86 == 0x15 || c->x86 == 0x16) - pr_cont("|%s|%s", - ((m->status & MCI_STATUS_DEFERRED) ? "Deferred" : "-"), - ((m->status & MCI_STATUS_POISON) ? "Poison" : "-")); - - /* do the two bits[14:13] together */ - ecc = (m->status >> 45) & 0x3; - if (ecc) - pr_cont("|%sECC", ((ecc == 2) ? "C" : "U")); - - pr_cont("]: 0x%016llx\n", m->status); - - if (m->status & MCI_STATUS_ADDRV) - pr_emerg(HW_ERR "MC%d_ADDR: 0x%016llx\n", m->bank, m->addr); - + err_code: amd_decode_err_code(m->status & 0xffff); return NOTIFY_STOP; @@ -816,10 +820,10 @@ static int __init mce_amd_init(void) struct cpuinfo_x86 *c = &boot_cpu_data; if (c->x86_vendor != X86_VENDOR_AMD) - return 0; + return -ENODEV; if (c->x86 < 0xf || c->x86 > 0x16) - return 0; + return -ENODEV; fam_ops = kzalloc(sizeof(struct amd_decoder_ops), GFP_KERNEL); if (!fam_ops) @@ -874,6 +878,7 @@ static int __init mce_amd_init(void) default: printk(KERN_WARNING "Huh? What family is it: 0x%x?!\n", c->x86); kfree(fam_ops); + fam_ops = NULL; return -EINVAL; } -- -- Regards/Gruss, Boris. Sent from a fat crate under my desk. Formatting is fine. -- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/