From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S937311AbYD1Uau (ORCPT ); Mon, 28 Apr 2008 16:30:50 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S934305AbYD1Uaj (ORCPT ); Mon, 28 Apr 2008 16:30:39 -0400 Received: from www.tglx.de ([62.245.132.106]:55157 "EHLO www.tglx.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1765866AbYD1Uai (ORCPT ); Mon, 28 Apr 2008 16:30:38 -0400 Date: Mon, 28 Apr 2008 22:30:25 +0200 (CEST) From: Thomas Gleixner To: PJ Waskiewicz cc: Linus Torvalds , LKML , "Eric W. Biederman" , netdev@vger.kernel.org Subject: Re: [PATCH] ARCH: Fix 32-bit x86 MSI-X allocation leakage In-Reply-To: <20080426005850.7098.77479.stgit@scrappy.jf.intel.com> Message-ID: References: <20080426005850.7098.77479.stgit@scrappy.jf.intel.com> User-Agent: Alpine 1.10 (LFD 962 2008-03-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 25 Apr 2008, PJ Waskiewicz wrote: > This bug was introduced in the 2.6.24 i386/x86_64 tree merge, where Can you please explain what exactly caused the bug. Definitely not the move from arch/i386 to arch/x86 as the code there was not changed at all and has not be changed since then. CC'ed Eric as well. Thanks tglx > MSI-X vector allocation will eventually fail. The cause is the new > bit array tracking used vectors is not getting cleared properly on > IRQ destruction on the 32-bit APIC code. > > This can be seen easily using the ixgbe 10 GbE driver on multi-core > systems by simply loading and unloading the driver a few times. > Depending on the number of available vectors on the host system, the > MSI-X allocation will eventually fail, and the driver will only be > able to use legacy interrupts. > > I am generating the same patch for both stable trees for 2.6.24 and > 2.6.25. > > Signed-off-by: Peter P Waskiewicz Jr > --- > > arch/x86/kernel/io_apic_32.c | 1 + > 1 files changed, 1 insertions(+), 0 deletions(-) > > > diff --git a/arch/x86/kernel/io_apic_32.c b/arch/x86/kernel/io_apic_32.c > index 2e2f420..77798b1 100644 > --- a/arch/x86/kernel/io_apic_32.c > +++ b/arch/x86/kernel/io_apic_32.c > @@ -2444,6 +2444,7 @@ void destroy_irq(unsigned int irq) > dynamic_irq_cleanup(irq); > > spin_lock_irqsave(&vector_lock, flags); > + clear_bit(irq_vector[irq], used_vectors); > irq_vector[irq] = 0; > spin_unlock_irqrestore(&vector_lock, flags); > } > > -- > 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/ >