From patchwork Thu Jun 12 21:48:49 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sohil Mehta X-Patchwork-Id: 895840 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.14]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9CB432E62DA; Thu, 12 Jun 2025 21:50:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.14 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749765038; cv=none; b=tKBssGT8Q/Pt5KJz04pJcGHk2zHkcsCCU88tzKHmxeRfvGy4UD3zOtjXA6ezHUSs6ruOpJYr1UXGlYlb0X80F4/lBzGX7v6BpI3IJWxVC5RSWHTk4stkFJ7VUymZJQ12IyyiHSnh2fZzuVVeFx70HSBSrsVfAsNxwDMkDKvkhUY= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749765038; c=relaxed/simple; bh=HAJ/WUjo+26I25B8LZv9C58T13MdBKPP51Ed+aO6Hzc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ASztzlx9wtE+vt0p8j88jlfD7qYz2/oIb8aP+XlrKWmX5//IEl2m5rDtpaQXkEgwyTd6J45eGhFZcGTaOzNW+alCOLTH9+E8DgdY6obTpgh1rPd3I9G+yYJu+pOwZy16YNwX1hFxDMOBaOAgp4dONqcigTclV7FmtXRNqoATen0= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=LmtUbBWU; arc=none smtp.client-ip=192.198.163.14 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="LmtUbBWU" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1749765037; x=1781301037; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=HAJ/WUjo+26I25B8LZv9C58T13MdBKPP51Ed+aO6Hzc=; b=LmtUbBWUPASfVQNSGYgP+FS0eqPi7EmSC6aDmkNtLrGtUBfNpSWxhM/B weos++PYbkhgJP78VLIlZhPK98vKpdFfkszpBGy/n/cha6jYvM94WBUOz 013cZm/7Dh9OhNMGAG5MyJllBuB/3gJCYU2GNG0LpAw3LlkYUaTuGx1On FgpSgYsSOu5/cjMk5yIiV2yobCgCvZxe709zlbC1EUNnN8aX2HuE3Vcjj +4Cjb6w55X2QXQ5EqycIOqzCO+sEP9l6rFSXg4BXU7U9z+SIsvwIILvSS vEWPw6vP1uEdt1DCBdAJB/NHL7MOgUzHVvwjdHbnAAGb1VWpuF3tHumvH Q==; X-CSE-ConnectionGUID: mpk+GHciSIaQcooH6X16jQ== X-CSE-MsgGUID: 9DKIFj24S7GMyR2vsMxIuA== X-IronPort-AV: E=McAfee;i="6800,10657,11462"; a="52065412" X-IronPort-AV: E=Sophos;i="6.16,231,1744095600"; d="scan'208";a="52065412" Received: from orviesa001.jf.intel.com ([10.64.159.141]) by fmvoesa108.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 Jun 2025 14:50:36 -0700 X-CSE-ConnectionGUID: 6shFoTgzT5Oy0swil4gfEA== X-CSE-MsgGUID: YGQBP4BrTL+w7Bg/am6Chw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.16,231,1744095600"; d="scan'208";a="184882009" Received: from sohilmeh.sc.intel.com ([172.25.103.65]) by orviesa001.jf.intel.com with ESMTP; 12 Jun 2025 14:50:35 -0700 From: Sohil Mehta To: x86@kernel.org, linux-kernel@vger.kernel.org Cc: Xin Li , "H . Peter Anvin" , Andy Lutomirski , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , Peter Zijlstra , Sean Christopherson , Adrian Hunter , Kan Liang , Tony Luck , Zhang Rui , Steven Rostedt , Sohil Mehta , Andrew Cooper , "Kirill A . Shutemov" , Jacob Pan , Andi Kleen , Kai Huang , Sandipan Das , linux-perf-users@vger.kernel.org, linux-edac@vger.kernel.org, kvm@vger.kernel.org, linux-pm@vger.kernel.org, linux-trace-kernel@vger.kernel.org Subject: [PATCH v7 10/10] x86/nmi: Print source information with the unknown NMI console message Date: Thu, 12 Jun 2025 14:48:49 -0700 Message-ID: <20250612214849.3950094-11-sohil.mehta@intel.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20250612214849.3950094-1-sohil.mehta@intel.com> References: <20250612214849.3950094-1-sohil.mehta@intel.com> Precedence: bulk X-Mailing-List: linux-pm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 The NMI-source bitmap is a useful piece of information provided by the NMI-source reporting feature. It is very helpful for debugging unknown NMIs, as it can pinpoint the exact source that caused the NMI. Print the complete source bitmap along with the "unknown NMI" kernel log message, since unexpected sources might have triggered the NMI. Signed-off-by: Sohil Mehta --- v7: No change. v6: Drop the tracepoint modification part for now. v5: New patch --- arch/x86/kernel/nmi.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/x86/kernel/nmi.c b/arch/x86/kernel/nmi.c index 3d2b636e9379..0b5bb20c5eb7 100644 --- a/arch/x86/kernel/nmi.c +++ b/arch/x86/kernel/nmi.c @@ -379,6 +379,9 @@ unknown_nmi_error(unsigned char reason, struct pt_regs *regs) pr_emerg_ratelimited("Uhhuh. NMI received for unknown reason %02x on CPU %d.\n", reason, smp_processor_id()); + if (cpu_feature_enabled(X86_FEATURE_NMI_SOURCE)) + pr_emerg_ratelimited("NMI-source bitmap is 0x%lx\n", fred_event_data(regs)); + if (unknown_nmi_panic || panic_on_unrecovered_nmi) nmi_panic(regs, "NMI: Not continuing");