From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marcin Slusarz Subject: Re: [PATCH] drm/nouveau: initialize chan->fence.lock before use Date: Sun, 9 Oct 2011 21:24:02 +0200 Message-ID: <20111009192402.GC3323@joi.lan> References: <20110909121642.GA16883@joi.lan> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <20110909121642.GA16883-OI9uyE9O0yo@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: nouveau-bounces+gcfxn-nouveau=m.gmane.org-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org Errors-To: nouveau-bounces+gcfxn-nouveau=m.gmane.org-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org To: Ben Skeggs Cc: nouveau-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org List-Id: nouveau.vger.kernel.org On Fri, Sep 09, 2011 at 02:16:42PM +0200, Marcin Slusarz wrote: > Fence lock needs to be initialized before any call to nouveau_channel_put > because it calls nouveau_channel_idle->nouveau_fence_update which uses > fence lock. > > BUG: spinlock bad magic on CPU#0, test/24134 > lock: ffff88019f90dba8, .magic: 00000000, .owner: /-1, .owner_cpu: 0 > Pid: 24134, comm: test Not tainted 3.0.0-nv+ #800 > Call Trace: > spin_bug+0x9c/0xa3 > do_raw_spin_lock+0x29/0x13c > _raw_spin_lock+0x1e/0x22 > nouveau_fence_update+0x2d/0xf1 > nouveau_channel_idle+0x22/0xa0 > nouveau_channel_put_unlocked+0x84/0x1bd > nouveau_channel_put+0x20/0x24 > nouveau_channel_alloc+0x4ec/0x585 > nouveau_ioctl_fifo_alloc+0x50/0x130 > drm_ioctl+0x289/0x361 > do_vfs_ioctl+0x4dd/0x52c > sys_ioctl+0x42/0x65 > system_call_fastpath+0x16/0x1b > > It's easily triggerable from userspace. > > Additionally remove double initialization of chan->fence.pending. > > Signed-off-by: Marcin Slusarz > Cc: stable-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org > --- > drivers/gpu/drm/nouveau/nouveau_channel.c | 1 + > drivers/gpu/drm/nouveau/nouveau_fence.c | 2 -- > 2 files changed, 1 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/nouveau/nouveau_channel.c b/drivers/gpu/drm/nouveau/nouveau_channel.c > index 85be745..62c09b0 100644 > --- a/drivers/gpu/drm/nouveau/nouveau_channel.c > +++ b/drivers/gpu/drm/nouveau/nouveau_channel.c > @@ -158,6 +158,7 @@ nouveau_channel_alloc(struct drm_device *dev, struct nouveau_channel **chan_ret, > INIT_LIST_HEAD(&chan->nvsw.vbl_wait); > INIT_LIST_HEAD(&chan->nvsw.flip); > INIT_LIST_HEAD(&chan->fence.pending); > + spin_lock_init(&chan->fence.lock); > > /* setup channel's memory and vm */ > ret = nouveau_gpuobj_channel_init(chan, vram_handle, gart_handle); > diff --git a/drivers/gpu/drm/nouveau/nouveau_fence.c b/drivers/gpu/drm/nouveau/nouveau_fence.c > index c499591..614e37a 100644 > --- a/drivers/gpu/drm/nouveau/nouveau_fence.c > +++ b/drivers/gpu/drm/nouveau/nouveau_fence.c > @@ -568,8 +568,6 @@ nouveau_fence_channel_init(struct nouveau_channel *chan) > return ret; > } > > - INIT_LIST_HEAD(&chan->fence.pending); > - spin_lock_init(&chan->fence.lock); > atomic_set(&chan->fence.last_sequence_irq, 0); > return 0; > } > -- ping