Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751895AbbGaMKx (ORCPT ); Fri, 31 Jul 2015 08:10:53 -0400 Received: from mail-oi0-f42.google.com ([209.85.218.42]:35493 "EHLO mail-oi0-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751183AbbGaMKw (ORCPT ); Fri, 31 Jul 2015 08:10:52 -0400 MIME-Version: 1.0 In-Reply-To: <20150731085750.GA8289@gmail.com> References: <1438148483-11932-1-git-send-email-brgerst@gmail.com> <1438148483-11932-6-git-send-email-brgerst@gmail.com> <20150731085750.GA8289@gmail.com> Date: Fri, 31 Jul 2015 08:10:51 -0400 Message-ID: Subject: Re: [PATCH 5/8] x86/vm86: Add a separate config option for hardware IRQ handling From: Brian Gerst To: Ingo Molnar Cc: "the arch/x86 maintainers" , Linux Kernel Mailing List , "H. Peter Anvin" , Denys Vlasenko , Andy Lutomirski , Linus Torvalds Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1785 Lines: 51 On Fri, Jul 31, 2015 at 4:57 AM, Ingo Molnar wrote: > > * Brian Gerst wrote: > >> Allow disabling hardware interrupt support for vm86. >> >> Signed-off-by: Brian Gerst >> --- >> arch/x86/Kconfig | 8 ++++++++ >> arch/x86/include/asm/irq_vectors.h | 10 ---------- >> arch/x86/include/asm/vm86.h | 20 ++++++++++++++++++-- >> arch/x86/kernel/vm86_32.c | 12 ++++++++++-- >> 4 files changed, 36 insertions(+), 14 deletions(-) >> >> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig >> index cbd2d62..7c7ec31 100644 >> --- a/arch/x86/Kconfig >> +++ b/arch/x86/Kconfig >> @@ -1067,6 +1067,14 @@ config VM86 >> bool >> default X86_LEGACY_VM86 >> >> +config VM86_INTERRUPTS >> + bool "Enable VM86 interrupt support" >> + default y >> + depends on VM86 >> + ---help--- >> + This option allows VM86 programs to request interrupts for >> + real mode hardware drivers. > > So I'm wondering what the justification for this is. People can disable vm86 > already via CONFIG_X86_LEGACY_VM86. The extra config just uglifies the code > unnecessarily. > > Thanks, > > Ingo Disabling even less-used code that could have system stability impact. We've discouraged user-mode drivers for a very long time. Ironically, other than being configured through the vm86 syscall, there isn't really anything vm86-specific about it. All it does is register an IRQ handler that sends a signal to the task. -- Brian Gerst -- 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/