From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 4055 invoked by alias); 26 Oct 2007 01:51:46 -0000 Received: (qmail 4046 invoked by uid 22791); 26 Oct 2007 01:51:46 -0000 X-Spam-Check-By: sourceware.org Received: from gate.crashing.org (HELO gate.crashing.org) (63.228.1.57) by sourceware.org (qpsmtpd/0.31) with ESMTP; Fri, 26 Oct 2007 01:51:44 +0000 Received: from [127.0.0.1] (localhost.localdomain [127.0.0.1]) by gate.crashing.org (8.13.8/8.13.8) with ESMTP id l9Q1pONB001401; Thu, 25 Oct 2007 20:51:27 -0500 Subject: Re: Apparent kernel bug with GDB on ppc405 From: Benjamin Herrenschmidt Reply-To: benh@kernel.crashing.org To: Daniel Jacobowitz Cc: Matt Mackall , gdb@sourceware.org, linuxppc-embedded@ozlabs.org In-Reply-To: <20071024224130.GA30819@caradoc.them.org> References: <20071024194640.GB19691@waste.org> <20071024204215.GC19691@waste.org> <20071024215421.GF19691@waste.org> <20071024223250.GI19691@waste.org> <20071024224130.GA30819@caradoc.them.org> Content-Type: text/plain Date: Fri, 26 Oct 2007 01:51:00 -0000 Message-Id: <1193363482.7018.41.camel@pasglop> Mime-Version: 1.0 X-Mailer: Evolution 2.12.0 Content-Transfer-Encoding: 7bit Mailing-List: contact gdb-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-owner@sourceware.org X-SW-Source: 2007-10/txt/msg00252.txt.bz2 On Wed, 2007-10-24 at 18:41 -0400, Daniel Jacobowitz wrote: > On Wed, Oct 24, 2007 at 05:32:50PM -0500, Matt Mackall wrote: > > Not completely implausible, but a) why isn't this seen on basically > > every machine with software TLB? b) why does -local- GDB, which is > > presumably doing much less work than gdbserver + network stack, not fail? > > You said it yourself. Local gdb does more work -> blows through more > TLB entries. > > I can't answer you about the other half, but I'm pretty sure TLB > invalidation is already supposed to be happening... somewhere. Yes. do_wp_page() -> ptep_clear_flush() -> flush_tlb_page() Ben.