Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758213AbYFZO3S (ORCPT ); Thu, 26 Jun 2008 10:29:18 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752859AbYFZO3H (ORCPT ); Thu, 26 Jun 2008 10:29:07 -0400 Received: from gw.goop.org ([64.81.55.164]:55825 "EHLO mail.goop.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751606AbYFZO3G (ORCPT ); Thu, 26 Jun 2008 10:29:06 -0400 Message-ID: <4863A7A3.201@goop.org> Date: Thu, 26 Jun 2008 07:28:51 -0700 From: Jeremy Fitzhardinge User-Agent: Thunderbird 2.0.0.14 (X11/20080501) MIME-Version: 1.0 To: Ingo Molnar CC: LKML , x86@kernel.org, xen-devel , Stephen Tweedie , Eduardo Habkost , Mark McLoughlin , Vegard Nossum , Nick Piggin , Yinghai Lu Subject: Re: [PATCH 00 of 36] x86/paravirt: groundwork for 64-bit Xen support References: <20080625084253.GA11524@elte.hu> <20080625152212.GA3442@elte.hu> <4862A6A9.1030109@goop.org> <20080626105722.GA12640@elte.hu> In-Reply-To: <20080626105722.GA12640@elte.hu> X-Enigmail-Version: 0.95.6 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2849 Lines: 96 Ingo Molnar wrote: > * Jeremy Fitzhardinge wrote: > > >>> It quickly broke the build in testing: >>> >>> include/asm/pgalloc.h: In function ‘paravirt_pgd_free': >>> include/asm/pgalloc.h:14: error: parameter name omitted >>> arch/x86/kernel/entry_64.S: In file included from >>> arch/x86/kernel/traps_64.c:51:include/asm/pgalloc.h: In function >>> ‘paravirt_pgd_free': >>> include/asm/pgalloc.h:14: error: parameter name omitted >>> >>> >> No, looks like my fault. The non-PARAVIRT version of >> paravirt_pgd_free() is: >> >> static inline void paravirt_pgd_free(struct mm_struct *mm, pgd_t *) {} >> >> but C doesn't like missing parameter names, even if unused. >> >> This should fix it: >> > > that fixed the build but now we've got a boot crash with this config: > > time.c: Detected 2010.304 MHz processor. > spurious 8259A interrupt: IRQ7. > BUG: unable to handle kernel NULL pointer dereference at 0000000000000000 > IP: [<0000000000000000>] > PGD 0 > Thread overran stack, or stack corrupted > Oops: 0010 [1] SMP > CPU 0 > > with: > > http://redhat.com/~mingo/misc/config-Thu_Jun_26_12_46_46_CEST_2008.bad > Blerg, a contextless NULL rip. Have you done any bisection on it? Could you try again with the same config, but with "CONFIG_PARAVIRT_DEBUG" enabled as well? That will BUG if it turns out to be trying to call a NULL paravirt-op I'll try to repro here anyway. > i've pushed out the current tip/xen-64bit branch, so that you can see > how things look like at the moment, but i cannot put it into tip/master > yet. Yeah, I was expecting things to break somewhere with this lot :/ Could you add this patch? I don't think it will help this case, but it's a bugfix. J Subject: x86_64: use SWAPGS_UNSAFE_STACK in ia32entry.S Use SWAPGS_UNSAFE_STACK in ia32entry.S in the places where the active stack is the usermode stack. Signed-off-by: Jeremy Fitzhardinge --- arch/x86/ia32/ia32entry.S | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) =================================================================== --- a/arch/x86/ia32/ia32entry.S +++ b/arch/x86/ia32/ia32entry.S @@ -98,7 +98,7 @@ CFI_SIGNAL_FRAME CFI_DEF_CFA rsp,0 CFI_REGISTER rsp,rbp - SWAPGS + SWAPGS_UNSAFE_STACK movq %gs:pda_kernelstack, %rsp addq $(PDA_STACKOFFSET),%rsp /* @@ -210,7 +210,7 @@ CFI_DEF_CFA rsp,PDA_STACKOFFSET CFI_REGISTER rip,rcx /*CFI_REGISTER rflags,r11*/ - SWAPGS + SWAPGS_UNSAFE_STACK movl %esp,%r8d CFI_REGISTER rsp,r8 movq %gs:pda_kernelstack,%rsp -- 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/