From: Maarten Lankhorst Date: Sun, 24 Mar 2013 11:56:30 +0000 (+0100) Subject: drm/nouveau: fix NULL ptr dereference from nv50_disp_intr() X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=e4604d8fe8492f8120cf92d4b60b3cc90ba87bd0;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git drm/nouveau: fix NULL ptr dereference from nv50_disp_intr() Op 23-03-13 12:47, Peter Hurley schreef: > On Tue, 2013-03-19 at 11:13 -0400, Peter Hurley wrote: >> On vanilla 3.9.0-rc3, I get this 100% repeatable oops after login when >> the user X session is coming up: > Perhaps I wasn't clear that this happens on every boot and is a > regression from 3.8 > > I'd be happy to help resolve this but time is of the essence; it would > be a shame to have to revert all of this for 3.9 Well it broke on my system too, so it was easy to fix. I didn't even need gdm to trigger it! >8---- This fixes regression caused by 1d7c71a3e2f7 (drm/nouveau/disp: port vblank handling to event interface), which causes a oops in the following way: BUG: unable to handle kernel NULL pointer dereference at 0000000000000001 IP: [<0000000000000001>] 0x0 PGD 0 Oops: 0010 [#1] PREEMPT SMP Modules linked in: ip6table_filter ip6_tables ebtable_nat ebtables ...... CPU 3 Pid: 0, comm: swapper/3 Not tainted 3.9.0-rc3-xeon #rc3 Dell Inc. Precision WorkStation T5400 /0RW203 RIP: 0010:[<0000000000000001>] [<0000000000000001>] 0x0 RSP: 0018:ffff8802afcc3d80 EFLAGS: 00010087 RAX: ffff88029f6e5808 RBX: 0000000000000001 RCX: 0000000000000000 RDX: 0000000000000096 RSI: 0000000000000001 RDI: ffff88029f6e5808 RBP: ffff8802afcc3dc8 R08: 0000000000000000 R09: 0000000000000004 R10: 000000000000002c R11: ffff88029e559a98 R12: ffff8802a376cb78 R13: ffff88029f6e57e0 R14: ffff88029f6e57f8 R15: ffff88029f6e5808 FS: 0000000000000000(0000) GS:ffff8802afcc0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 0000000000000001 CR3: 000000029fa67000 CR4: 00000000000007e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process swapper/3 (pid: 0, threadinfo ffff8802a355e000, task ffff8802a3535c40) Stack: ffffffffa0159d8a 0000000000000082 ffff88029f6e5820 0000000000000001 ffff88029f71aa00 0000000000000000 0000000000000000 0000000004000000 0000000004000000 ffff8802afcc3e38 ffffffffa01843b5 ffff8802afcc3df8 Call Trace: [] ? nouveau_event_trigger+0xaa/0xe0 [nouveau] [] nv50_disp_intr+0xc5/0x200 [nouveau] [] ? _raw_spin_unlock_irqrestore+0x2c/0x50 [] ? notifier_call_chain+0x4d/0x70 [] nouveau_mc_intr+0xb5/0x110 [nouveau] [] nouveau_irq_handler+0x6f/0x80 [nouveau] [] handle_irq_event_percpu+0x75/0x260 [] handle_irq_event+0x48/0x70 [] handle_fasteoi_irq+0x5a/0x100 [] handle_irq+0x22/0x40 [] do_IRQ+0x5a/0xd0 [] common_interrupt+0x6d/0x6d [] ? native_safe_halt+0x6/0x10 [] default_idle+0x3d/0x170 [] cpu_idle+0x116/0x130 [] start_secondary+0x251/0x258 Code: Bad RIP value. RIP [<0000000000000001>] 0x0 RSP CR2: 0000000000000001 ---[ end trace 907323cb8ce6f301 ]--- Signed-off-by: Maarten Lankhorst Signed-off-by: Ben Skeggs --- diff --git a/drivers/gpu/drm/nouveau/nouveau_drm.c b/drivers/gpu/drm/nouveau/nouveau_drm.c index d1099365bfc1..c95decf543e9 100644 --- a/drivers/gpu/drm/nouveau/nouveau_drm.c +++ b/drivers/gpu/drm/nouveau/nouveau_drm.c @@ -71,12 +71,26 @@ module_param_named(modeset, nouveau_modeset, int, 0400); static struct drm_driver driver; +static int +nouveau_drm_vblank_handler(struct nouveau_eventh *event, int head) +{ + struct nouveau_drm *drm = + container_of(event, struct nouveau_drm, vblank[head]); + drm_handle_vblank(drm->dev, head); + return NVKM_EVENT_KEEP; +} + static int nouveau_drm_vblank_enable(struct drm_device *dev, int head) { struct nouveau_drm *drm = nouveau_drm(dev); struct nouveau_disp *pdisp = nouveau_disp(drm->device); - nouveau_event_get(pdisp->vblank, head, &drm->vblank); + + if (WARN_ON_ONCE(head > ARRAY_SIZE(drm->vblank))) + return -EIO; + WARN_ON_ONCE(drm->vblank[head].func); + drm->vblank[head].func = nouveau_drm_vblank_handler; + nouveau_event_get(pdisp->vblank, head, &drm->vblank[head]); return 0; } @@ -85,16 +99,11 @@ nouveau_drm_vblank_disable(struct drm_device *dev, int head) { struct nouveau_drm *drm = nouveau_drm(dev); struct nouveau_disp *pdisp = nouveau_disp(drm->device); - nouveau_event_put(pdisp->vblank, head, &drm->vblank); -} - -static int -nouveau_drm_vblank_handler(struct nouveau_eventh *event, int head) -{ - struct nouveau_drm *drm = - container_of(event, struct nouveau_drm, vblank); - drm_handle_vblank(drm->dev, head); - return NVKM_EVENT_KEEP; + if (drm->vblank[head].func) + nouveau_event_put(pdisp->vblank, head, &drm->vblank[head]); + else + WARN_ON_ONCE(1); + drm->vblank[head].func = NULL; } static u64 @@ -292,7 +301,6 @@ nouveau_drm_load(struct drm_device *dev, unsigned long flags) dev->dev_private = drm; drm->dev = dev; - drm->vblank.func = nouveau_drm_vblank_handler; INIT_LIST_HEAD(&drm->clients); spin_lock_init(&drm->tile.lock); diff --git a/drivers/gpu/drm/nouveau/nouveau_drm.h b/drivers/gpu/drm/nouveau/nouveau_drm.h index b25df374c901..9c39bafbef2c 100644 --- a/drivers/gpu/drm/nouveau/nouveau_drm.h +++ b/drivers/gpu/drm/nouveau/nouveau_drm.h @@ -113,7 +113,7 @@ struct nouveau_drm { struct nvbios vbios; struct nouveau_display *display; struct backlight_device *backlight; - struct nouveau_eventh vblank; + struct nouveau_eventh vblank[4]; /* power management */ struct nouveau_pm *pm;