From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964949AbdKGKTj (ORCPT ); Tue, 7 Nov 2017 05:19:39 -0500 Received: from terminus.zytor.com ([65.50.211.136]:34181 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752139AbdKGKTg (ORCPT ); Tue, 7 Nov 2017 05:19:36 -0500 Date: Tue, 7 Nov 2017 02:15:46 -0800 From: tip-bot for Yazen Ghannam Message-ID: Cc: tony.luck@intel.com, bp@suse.de, yazen.ghannam@amd.com, peterz@infradead.org, linux-kernel@vger.kernel.org, hpa@zytor.com, torvalds@linux-foundation.org, linux-edac@vger.kernel.org, tglx@linutronix.de, mingo@kernel.org Reply-To: mingo@kernel.org, torvalds@linux-foundation.org, linux-edac@vger.kernel.org, tglx@linutronix.de, yazen.ghannam@amd.com, peterz@infradead.org, linux-kernel@vger.kernel.org, hpa@zytor.com, bp@suse.de, tony.luck@intel.com In-Reply-To: <20171106174633.13576-1-bp@alien8.de> References: <20171106174633.13576-1-bp@alien8.de> To: linux-tip-commits@vger.kernel.org Subject: [tip:ras/core] x86/MCE/AMD: Always give panic severity for UC errors in kernel context Git-Commit-ID: d65dfc81bb3894fdb68cbc74bbf5fb48d2354071 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: d65dfc81bb3894fdb68cbc74bbf5fb48d2354071 Gitweb: https://git.kernel.org/tip/d65dfc81bb3894fdb68cbc74bbf5fb48d2354071 Author: Yazen Ghannam AuthorDate: Mon, 6 Nov 2017 18:46:32 +0100 Committer: Ingo Molnar CommitDate: Tue, 7 Nov 2017 11:07:50 +0100 x86/MCE/AMD: Always give panic severity for UC errors in kernel context The AMD severity grading function was introduced in kernel 4.1. The current logic can possibly give MCE_AR_SEVERITY for uncorrectable errors in kernel context. The system may then get stuck in a loop as memory_failure() will try to handle the bad kernel memory and find it busy. Return MCE_PANIC_SEVERITY for all UC errors IN_KERNEL context on AMD systems. After: b2f9d678e28c ("x86/mce: Check for faults tagged in EXTABLE_CLASS_FAULT exception table entries") was accepted in v4.6, this issue was masked because of the tail-end attempt at kernel mode recovery in the #MC handler. However, uncorrectable errors IN_KERNEL context should always be considered unrecoverable and cause a panic. Signed-off-by: Yazen Ghannam Signed-off-by: Borislav Petkov Cc: # 4.9.x Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Tony Luck Cc: linux-edac Fixes: bf80bbd7dcf5 (x86/mce: Add an AMD severities-grading function) Link: http://lkml.kernel.org/r/20171106174633.13576-1-bp@alien8.de Signed-off-by: Ingo Molnar --- arch/x86/kernel/cpu/mcheck/mce-severity.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/arch/x86/kernel/cpu/mcheck/mce-severity.c b/arch/x86/kernel/cpu/mcheck/mce-severity.c index 87cc9ab..4b81876 100644 --- a/arch/x86/kernel/cpu/mcheck/mce-severity.c +++ b/arch/x86/kernel/cpu/mcheck/mce-severity.c @@ -245,6 +245,9 @@ static int mce_severity_amd(struct mce *m, int tolerant, char **msg, bool is_exc if (m->status & MCI_STATUS_UC) { + if (ctx == IN_KERNEL) + return MCE_PANIC_SEVERITY; + /* * On older systems where overflow_recov flag is not present, we * should simply panic if an error overflow occurs. If @@ -255,10 +258,6 @@ static int mce_severity_amd(struct mce *m, int tolerant, char **msg, bool is_exc if (mce_flags.smca) return mce_severity_amd_smca(m, ctx); - /* software can try to contain */ - if (!(m->mcgstatus & MCG_STATUS_RIPV) && (ctx == IN_KERNEL)) - return MCE_PANIC_SEVERITY; - /* kill current process */ return MCE_AR_SEVERITY; } else { From mboxrd@z Thu Jan 1 00:00:00 1970 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: base64 Subject: [tip:ras/core] x86/MCE/AMD: Always give panic severity for UC errors in kernel context From: tip-bot for Borislav Petkov Message-Id: Date: Tue, 7 Nov 2017 02:15:46 -0800 To: linux-tip-commits@vger.kernel.org Cc: tony.luck@intel.com, bp@suse.de, yazen.ghannam@amd.com, peterz@infradead.org, linux-kernel@vger.kernel.org, hpa@zytor.com, torvalds@linux-foundation.org, linux-edac@vger.kernel.org, tglx@linutronix.de, mingo@kernel.org List-ID: Q29tbWl0LUlEOiAgZDY1ZGZjODFiYjM4OTRmZGI2OGNiYzc0YmJmNWZiNDhkMjM1NDA3MQpHaXR3 ZWI6ICAgICBodHRwczovL2dpdC5rZXJuZWwub3JnL3RpcC9kNjVkZmM4MWJiMzg5NGZkYjY4Y2Jj NzRiYmY1ZmI0OGQyMzU0MDcxCkF1dGhvcjogICAgIFlhemVuIEdoYW5uYW0gPHlhemVuLmdoYW5u YW1AYW1kLmNvbT4KQXV0aG9yRGF0ZTogTW9uLCA2IE5vdiAyMDE3IDE4OjQ2OjMyICswMTAwCkNv bW1pdHRlcjogIEluZ28gTW9sbmFyIDxtaW5nb0BrZXJuZWwub3JnPgpDb21taXREYXRlOiBUdWUs IDcgTm92IDIwMTcgMTE6MDc6NTAgKzAxMDAKCng4Ni9NQ0UvQU1EOiBBbHdheXMgZ2l2ZSBwYW5p YyBzZXZlcml0eSBmb3IgVUMgZXJyb3JzIGluIGtlcm5lbCBjb250ZXh0CgpUaGUgQU1EIHNldmVy aXR5IGdyYWRpbmcgZnVuY3Rpb24gd2FzIGludHJvZHVjZWQgaW4ga2VybmVsIDQuMS4gVGhlCmN1 cnJlbnQgbG9naWMgY2FuIHBvc3NpYmx5IGdpdmUgTUNFX0FSX1NFVkVSSVRZIGZvciB1bmNvcnJl Y3RhYmxlCmVycm9ycyBpbiBrZXJuZWwgY29udGV4dC4gVGhlIHN5c3RlbSBtYXkgdGhlbiBnZXQg c3R1Y2sgaW4gYSBsb29wIGFzCm1lbW9yeV9mYWlsdXJlKCkgd2lsbCB0cnkgdG8gaGFuZGxlIHRo ZSBiYWQga2VybmVsIG1lbW9yeSBhbmQgZmluZCBpdApidXN5LgoKUmV0dXJuIE1DRV9QQU5JQ19T RVZFUklUWSBmb3IgYWxsIFVDIGVycm9ycyBJTl9LRVJORUwgY29udGV4dCBvbiBBTUQKc3lzdGVt cy4KCkFmdGVyOgoKICBiMmY5ZDY3OGUyOGMgKCJ4ODYvbWNlOiBDaGVjayBmb3IgZmF1bHRzIHRh Z2dlZCBpbiBFWFRBQkxFX0NMQVNTX0ZBVUxUIGV4Y2VwdGlvbiB0YWJsZSBlbnRyaWVzIikKCndh cyBhY2NlcHRlZCBpbiB2NC42LCB0aGlzIGlzc3VlIHdhcyBtYXNrZWQgYmVjYXVzZSBvZiB0aGUg dGFpbC1lbmQgYXR0ZW1wdAphdCBrZXJuZWwgbW9kZSByZWNvdmVyeSBpbiB0aGUgI01DIGhhbmRs ZXIuCgpIb3dldmVyLCB1bmNvcnJlY3RhYmxlIGVycm9ycyBJTl9LRVJORUwgY29udGV4dCBzaG91 bGQgYWx3YXlzIGJlIGNvbnNpZGVyZWQKdW5yZWNvdmVyYWJsZSBhbmQgY2F1c2UgYSBwYW5pYy4K ClNpZ25lZC1vZmYtYnk6IFlhemVuIEdoYW5uYW0gPHlhemVuLmdoYW5uYW1AYW1kLmNvbT4KU2ln bmVkLW9mZi1ieTogQm9yaXNsYXYgUGV0a292IDxicEBzdXNlLmRlPgpDYzogPHN0YWJsZUB2Z2Vy Lmtlcm5lbC5vcmc+ICMgNC45LngKQ2M6IExpbnVzIFRvcnZhbGRzIDx0b3J2YWxkc0BsaW51eC1m b3VuZGF0aW9uLm9yZz4KQ2M6IFBldGVyIFppamxzdHJhIDxwZXRlcnpAaW5mcmFkZWFkLm9yZz4K Q2M6IFRob21hcyBHbGVpeG5lciA8dGdseEBsaW51dHJvbml4LmRlPgpDYzogVG9ueSBMdWNrIDx0 b255Lmx1Y2tAaW50ZWwuY29tPgpDYzogbGludXgtZWRhYyA8bGludXgtZWRhY0B2Z2VyLmtlcm5l bC5vcmc+CkZpeGVzOiBiZjgwYmJkN2RjZjUgKHg4Ni9tY2U6IEFkZCBhbiBBTUQgc2V2ZXJpdGll cy1ncmFkaW5nIGZ1bmN0aW9uKQpMaW5rOiBodHRwOi8vbGttbC5rZXJuZWwub3JnL3IvMjAxNzEx MDYxNzQ2MzMuMTM1NzYtMS1icEBhbGllbjguZGUKU2lnbmVkLW9mZi1ieTogSW5nbyBNb2xuYXIg PG1pbmdvQGtlcm5lbC5vcmc+Ci0tLQogYXJjaC94ODYva2VybmVsL2NwdS9tY2hlY2svbWNlLXNl dmVyaXR5LmMgfCA3ICsrKy0tLS0KIDEgZmlsZSBjaGFuZ2VkLCAzIGluc2VydGlvbnMoKyksIDQg ZGVsZXRpb25zKC0pCgotLQpUbyB1bnN1YnNjcmliZSBmcm9tIHRoaXMgbGlzdDogc2VuZCB0aGUg bGluZSAidW5zdWJzY3JpYmUgbGludXgtZWRhYyIgaW4KdGhlIGJvZHkgb2YgYSBtZXNzYWdlIHRv IG1ham9yZG9tb0B2Z2VyLmtlcm5lbC5vcmcKTW9yZSBtYWpvcmRvbW8gaW5mbyBhdCAgaHR0cDov L3ZnZXIua2VybmVsLm9yZy9tYWpvcmRvbW8taW5mby5odG1sCgpkaWZmIC0tZ2l0IGEvYXJjaC94 ODYva2VybmVsL2NwdS9tY2hlY2svbWNlLXNldmVyaXR5LmMgYi9hcmNoL3g4Ni9rZXJuZWwvY3B1 L21jaGVjay9tY2Utc2V2ZXJpdHkuYwppbmRleCA4N2NjOWFiLi40YjgxODc2IDEwMDY0NAotLS0g YS9hcmNoL3g4Ni9rZXJuZWwvY3B1L21jaGVjay9tY2Utc2V2ZXJpdHkuYworKysgYi9hcmNoL3g4 Ni9rZXJuZWwvY3B1L21jaGVjay9tY2Utc2V2ZXJpdHkuYwpAQCAtMjQ1LDYgKzI0NSw5IEBAIHN0 YXRpYyBpbnQgbWNlX3NldmVyaXR5X2FtZChzdHJ1Y3QgbWNlICptLCBpbnQgdG9sZXJhbnQsIGNo YXIgKiptc2csIGJvb2wgaXNfZXhjCiAKIAlpZiAobS0+c3RhdHVzICYgTUNJX1NUQVRVU19VQykg ewogCisJCWlmIChjdHggPT0gSU5fS0VSTkVMKQorCQkJcmV0dXJuIE1DRV9QQU5JQ19TRVZFUklU WTsKKwogCQkvKgogCQkgKiBPbiBvbGRlciBzeXN0ZW1zIHdoZXJlIG92ZXJmbG93X3JlY292IGZs YWcgaXMgbm90IHByZXNlbnQsIHdlCiAJCSAqIHNob3VsZCBzaW1wbHkgcGFuaWMgaWYgYW4gZXJy b3Igb3ZlcmZsb3cgb2NjdXJzLiBJZgpAQCAtMjU1LDEwICsyNTgsNiBAQCBzdGF0aWMgaW50IG1j ZV9zZXZlcml0eV9hbWQoc3RydWN0IG1jZSAqbSwgaW50IHRvbGVyYW50LCBjaGFyICoqbXNnLCBi b29sIGlzX2V4YwogCQkJaWYgKG1jZV9mbGFncy5zbWNhKQogCQkJCXJldHVybiBtY2Vfc2V2ZXJp dHlfYW1kX3NtY2EobSwgY3R4KTsKIAotCQkJLyogc29mdHdhcmUgY2FuIHRyeSB0byBjb250YWlu ICovCi0JCQlpZiAoIShtLT5tY2dzdGF0dXMgJiBNQ0dfU1RBVFVTX1JJUFYpICYmIChjdHggPT0g SU5fS0VSTkVMKSkKLQkJCQlyZXR1cm4gTUNFX1BBTklDX1NFVkVSSVRZOwotCiAJCQkvKiBraWxs IGN1cnJlbnQgcHJvY2VzcyAqLwogCQkJcmV0dXJuIE1DRV9BUl9TRVZFUklUWTsKIAkJfSBlbHNl IHsK