From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B8ADCC001DE for ; Mon, 31 Jul 2023 21:47:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231466AbjGaVrq (ORCPT ); Mon, 31 Jul 2023 17:47:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57064 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229486AbjGaVrp (ORCPT ); Mon, 31 Jul 2023 17:47:45 -0400 Received: from mail.zytor.com (unknown [IPv6:2607:7c80:54:3::138]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9C174114; Mon, 31 Jul 2023 14:47:43 -0700 (PDT) Received: from [192.168.105.249] ([75.104.94.137]) (authenticated bits=0) by mail.zytor.com (8.17.1/8.17.1) with ESMTPSA id 36VLiSLD3093143 (version=TLSv1.3 cipher=TLS_AES_128_GCM_SHA256 bits=128 verify=NO); Mon, 31 Jul 2023 14:44:34 -0700 DKIM-Filter: OpenDKIM Filter v2.11.0 mail.zytor.com 36VLiSLD3093143 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=zytor.com; s=2023071101; t=1690839952; bh=Hg2XSL3316ANoXYXjd63x+cCNIVtiqBW14cv6sKLqfM=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=OJyzPW65vrM8sDH6eNGy+5kWbcB7PMYBpzWhQpIWkaAZClwYLyiR8q3r0h24DHa+i plc1tYwGV1X0jnVZoHyMcH21g4d3T5nrZNciwkD9pXyPp9eyd7deKj5//687qepUUN GajcQAPfiwt5T7KF3w3EDPjhuU+UOb+SXF0Ey3xPLdCdh2vlXfVnIDfD1LR2iQn1Q3 +p5bLyY/BkC4u9rExXSQvakREpl4pn+K6rV/GzfnNnDvo8xR1x7/0XAWYi0JZGxsUi 6sYcbHmh6hzcml78uw2uhAQKsHCzb+/6sFfciH7vXjmIcsvNRtd0H0JUkcPZnEheRh J+lI/W952JXBg== Message-ID: <4ccbf0e9-716d-dfe0-537c-210e5455418c@zytor.com> Date: Mon, 31 Jul 2023 14:44:20 -0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.13.0 Subject: Re: [PATCH v9 29/36] x86/fred: FRED entry/exit and dispatch code Content-Language: en-US To: Xin Li , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org Cc: Jonathan Corbet , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, Andy Lutomirski , Oleg Nesterov , Tony Luck , "K . Y . Srinivasan" , Haiyang Zhang , Wei Liu , Dexuan Cui , Paolo Bonzini , Wanpeng Li , Vitaly Kuznetsov , Sean Christopherson , Peter Zijlstra , Juergen Gross , Stefano Stabellini , Oleksandr Tyshchenko , Josh Poimboeuf , "Paul E . McKenney" , Catalin Marinas , Randy Dunlap , Steven Rostedt , Kim Phillips , Hyeonggon Yoo <42.hyeyoo@gmail.com>, "Liam R . Howlett" , Sebastian Reichel , "Kirill A . Shutemov" , Suren Baghdasaryan , Pawan Gupta , Jiaxi Chen , Babu Moger , Jim Mattson , Sandipan Das , Lai Jiangshan , Hans de Goede , Reinette Chatre , Daniel Sneddon , Breno Leitao , Nikunj A Dadhania , Brian Gerst , Sami Tolvanen , Alexander Potapenko , Andrew Morton , Arnd Bergmann , "Eric W . Biederman" , Kees Cook , Masami Hiramatsu , Masahiro Yamada , Ze Gao , Fei Li , Conghui , Ashok Raj , "Jason A . Donenfeld" , Mark Rutland , Jacob Pan , Jiapeng Chong , Jane Malalane , David Woodhouse , Boris Ostrovsky , Arnaldo Carvalho de Melo , Yantengsi , Christophe Leroy , Sathvika Vasireddy References: <20230731064119.3870-1-xin3.li@intel.com> From: "H. Peter Anvin" In-Reply-To: <20230731064119.3870-1-xin3.li@intel.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-hyperv@vger.kernel.org On 7/30/23 23:41, Xin Li wrote: > + > +static DEFINE_FRED_HANDLER(fred_sw_interrupt_user) > +{ > + /* > + * In compat mode INT $0x80 (32bit system call) is > + * performance-critical. Handle it first. > + */ > + if (IS_ENABLED(CONFIG_IA32_EMULATION) && > + likely(regs->vector == IA32_SYSCALL_VECTOR)) { > + regs->orig_ax = regs->ax; > + regs->ax = -ENOSYS; > + return do_int80_syscall_32(regs); > + } We can presumably drop the early out here as well... > + > + /* > + * Some software exceptions can also be triggered as > + * int instructions, for historical reasons. > + */ > + switch (regs->vector) { > + case X86_TRAP_BP: > + case X86_TRAP_OF: > + fred_emulate_trap(regs); > + break; > + default: > + regs->vector = X86_TRAP_GP; > + fred_emulate_fault(regs); > + break; > + } > +} > +