From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: BUG: sleeping function called from invalid context at mm/slub.c:793 Date: Tue, 11 Jan 2011 11:49:17 +0200 Message-ID: <4D2C279D.5050309@redhat.com> References: <20110110105433.GA17881@shutemov.name> <20110110193117.GA20027@shutemov.name> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Christoph Lameter , Marcelo Tosatti , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , x86@kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Pekka Enberg To: "Kirill A. Shutemov" Return-path: Received: from mx1.redhat.com ([209.132.183.28]:21342 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751425Ab1AKJtl (ORCPT ); Tue, 11 Jan 2011 04:49:41 -0500 In-Reply-To: <20110110193117.GA20027@shutemov.name> Sender: kvm-owner@vger.kernel.org List-ID: On 01/10/2011 09:31 PM, Kirill A. Shutemov wrote: > On Mon, Jan 10, 2011 at 10:52:05AM -0600, Christoph Lameter wrote: > > > > On Mon, 10 Jan 2011, Kirill A. Shutemov wrote: > > > > > Every time I run qemu with KVM enabled I get this in dmesg: > > > > > > [ 182.878328] BUG: sleeping function called from invalid context at mm/slub.c:793 > > > [ 182.878339] in_atomic(): 1, irqs_disabled(): 0, pid: 4992, name: qemu > > > [ 182.878355] Pid: 4992, comm: qemu Not tainted 2.6.37+ #31 > > > [ 182.878361] Call Trace: > > > [ 182.878381] [] ? __might_sleep+0xd0/0xd7 > > > [ 182.878394] [] ? slab_pre_alloc_hook.clone.39+0x23/0x27 > > > [ 182.878404] [] ? kmem_cache_alloc+0x22/0xc8 > > > [ 182.878414] [] ? init_fpu+0x44/0x7b > > > > fpu_alloc() does call kmem_cache_alloc with GFP_KERNEL although we are in > > an atomic context. > > Something like this? > > --- > From 7c6fbfed72e7d22cbdf7393f9711d521e0fbb4a6 Mon Sep 17 00:00:00 2001 > From: Kirill A. Shutemov > Date: Mon, 10 Jan 2011 21:24:23 +0200 > Subject: [PATCH] x86, fpu_alloc(): call kmem_cache_alloc() with GFP_ATOMIC > > [ 182.878328] BUG: sleeping function called from invalid context at mm/slub.c:793 > [ 182.878339] in_atomic(): 1, irqs_disabled(): 0, pid: 4992, name: qemu > [ 182.878355] Pid: 4992, comm: qemu Not tainted 2.6.37+ #31 > [ 182.878361] Call Trace: > [ 182.878381] [] ? __might_sleep+0xd0/0xd7 > [ 182.878394] [] ? slab_pre_alloc_hook.clone.39+0x23/0x27 > [ 182.878404] [] ? kmem_cache_alloc+0x22/0xc8 > [ 182.878414] [] ? init_fpu+0x44/0x7b > [ 182.878426] [] ? do_device_not_available+0x0/0x1b > [ 182.878435] [] ? init_fpu+0x44/0x7b > [ 182.878444] [] ? math_state_restore+0x24/0x47 > [ 182.878453] [] ? do_device_not_available+0x10/0x1b > [ 182.878462] [] ? error_code+0x67/0x6c > [ 182.878475] [] ? kvm_load_guest_fpu+0xa1/0xaa > [ 182.878484] [] ? kvm_arch_vcpu_ioctl_run+0x798/0xbe8 > [ 182.878496] [] ? kvm_vcpu_ioctl+0x105/0x46e > [ 182.878508] [] ? get_futex_key+0x73/0x132 > [ 182.878517] [] ? futex_wake+0xb6/0xc0 > [ 182.878527] [] ? do_futex+0x87/0x669 > [ 182.878535] [] ? kvm_vcpu_ioctl+0x0/0x46e > [ 182.878545] [] ? do_vfs_ioctl+0x4a0/0x4d1 > [ 182.878554] [] ? do_page_fault+0x2eb/0x316 > [ 182.878564] [] ? sys_ioctl+0x46/0x68 > [ 182.878572] [] ? syscall_call+0x7/0xb > [ 182.878585] [] ? aer_probe+0x1da/0x274 > > Signed-off-by: Kirill A. Shutemov > --- > arch/x86/include/asm/i387.h | 2 +- > 1 files changed, 1 insertions(+), 1 deletions(-) > > diff --git a/arch/x86/include/asm/i387.h b/arch/x86/include/asm/i387.h > index ef32890..8b896dd 100644 > --- a/arch/x86/include/asm/i387.h > +++ b/arch/x86/include/asm/i387.h > @@ -426,7 +426,7 @@ static inline int fpu_alloc(struct fpu *fpu) > { > if (fpu_allocated(fpu)) > return 0; > - fpu->state = kmem_cache_alloc(task_xstate_cachep, GFP_KERNEL); > + fpu->state = kmem_cache_alloc(task_xstate_cachep, GFP_ATOMIC); > if (!fpu->state) > return -ENOMEM; > WARN_ON((unsigned long)fpu->state& 15); If this fails, a task will be killed. I'll patch kvm to ensure that the fpu is initialized. -- error compiling committee.c: too many arguments to function