From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga18.intel.com (mga18.intel.com [134.134.136.126]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4157kC361lzDqsx for ; Wed, 13 Jun 2018 11:01:39 +1000 (AEST) From: Ricardo Neri To: Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" Cc: Andi Kleen , Ashok Raj , Borislav Petkov , Tony Luck , "Ravi V. Shankar" , x86@kernel.org, sparclinux@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, Ricardo Neri , Jacob Pan , Juergen Gross , Baoquan He , "Eric W. Biederman" , Dou Liyang , Jan Kiszka , iommu@lists.linux-foundation.org Subject: [RFC PATCH 06/23] x86/ioapic: Add support for IRQCHIP_CAN_DELIVER_AS_NMI with interrupt remapping Date: Tue, 12 Jun 2018 17:57:26 -0700 Message-Id: <1528851463-21140-7-git-send-email-ricardo.neri-calderon@linux.intel.com> In-Reply-To: <1528851463-21140-1-git-send-email-ricardo.neri-calderon@linux.intel.com> References: <1528851463-21140-1-git-send-email-ricardo.neri-calderon@linux.intel.com> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Even though there is a delivery mode field at the entries of an IO APIC's redirection table, the documentation of the majority of the IO APICs explicitly states that interrupt delivery as non-maskable is not supported. Thus, However, when using an IO APIC in combination with the Intel VT-d interrupt remapping functionality, the delivery of the interrupt to the CPU is handled by the remapping hardware. In such a case, the interrupt can be delivered as non maskable. Thus, add the IRQCHIP_CAN_DELIVER_AS_NMI flag only when used in combination with interrupt remapping. Cc: Ashok Raj Cc: Andi Kleen Cc: Tony Luck Cc: Borislav Petkov Cc: Jacob Pan Cc: Juergen Gross Cc: Baoquan He Cc: "Eric W. Biederman" Cc: Dou Liyang Cc: Jan Kiszka Cc: "Ravi V. Shankar" Cc: x86@kernel.org Cc: iommu@lists.linux-foundation.org Signed-off-by: Ricardo Neri --- arch/x86/kernel/apic/io_apic.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c index 10a20f8..39de91b 100644 --- a/arch/x86/kernel/apic/io_apic.c +++ b/arch/x86/kernel/apic/io_apic.c @@ -1911,7 +1911,8 @@ static struct irq_chip ioapic_ir_chip __read_mostly = { .irq_eoi = ioapic_ir_ack_level, .irq_set_affinity = ioapic_set_affinity, .irq_retrigger = irq_chip_retrigger_hierarchy, - .flags = IRQCHIP_SKIP_SET_WAKE, + .flags = IRQCHIP_SKIP_SET_WAKE | + IRQCHIP_CAN_DELIVER_AS_NMI, }; static inline void init_IO_APIC_traps(void) -- 2.7.4