@@ -496,6 +496,7 @@ bool i915_semaphore_is_enabled(struct dr
void intel_hpd_cancel_work(struct drm_i915_private *dev_priv)
{
+ trace_printk("CANCEL\n");
spin_lock_irq(&dev_priv->irq_lock);
dev_priv->long_hpd_port_mask = 0;
@@ -507,6 +508,7 @@ void intel_hpd_cancel_work(struct drm_i9
cancel_work_sync(&dev_priv->dig_port_work);
cancel_work_sync(&dev_priv->hotplug_work);
cancel_delayed_work_sync(&dev_priv->hotplug_reenable_work);
+ trace_printk("CANCEL DONE\n");
}
static void intel_suspend_encoders(struct drm_i915_private *dev_priv)
@@ -1100,6 +1100,7 @@ static void i915_digport_work_func(struc
int i, ret;
u32 old_bits = 0;
+ trace_printk("WORK\n");
spin_lock_irqsave(&dev_priv->irq_lock, irqflags);
long_port_mask = dev_priv->long_hpd_port_mask;
dev_priv->long_hpd_port_mask = 0;
@@ -1757,10 +1758,13 @@ static inline void intel_hpd_irq_handler
spin_lock(&dev_priv->irq_lock);
for (i = 1; i < HPD_NUM_PINS; i++) {
- if (!(hpd[i] & hotplug_trigger))
+ if (!(hpd[i] & hotplug_trigger)) {
+ trace_printk("PIN %d continue\n", i);
continue;
+ }
port = get_port_from_pin(i);
+ trace_printk("PORT %d PIN %d continue\n", port, i);
if (port && dev_priv->hpd_irq_port[port]) {
bool long_hpd;
@@ -1784,6 +1788,7 @@ static inline void intel_hpd_irq_handler
hotplug_trigger &= ~hpd[i];
}
queue_dig = true;
+ trace_printk("PORT %d PIN %d sets queue_dig = true\n", port, i);
}
}
@@ -1840,8 +1845,10 @@ static inline void intel_hpd_irq_handler
* queue for otherwise the flush_work in the pageflip code will
* deadlock.
*/
- if (queue_dig)
+ if (queue_dig) {
+ trace_printk("QUEUE\n");
queue_work(dev_priv->dp_wq, &dev_priv->dig_port_work);
+ }
if (queue_hp)
schedule_work(&dev_priv->hotplug_work);
}
Non-deterministic explosion culprit is the below. The commit says it adds mysterious acronyms to Haswell, so I suspect my little core2 lappy isn't ever supposed to see this code. The ftrace buffer is in fact empty after a successful boot. commit 0e32b39ceed665bfa4a77a4bc307b6652b991632 Author: Dave Airlie <airlied@redhat.com> Date: Fri May 2 14:02:48 2014 +1000 drm/i915: add DP 1.2 MST support (v0.7) This adds DP 1.2 MST support on Haswell systems. [ 4.251017] ********************************************************** [ 4.251018] ** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE ** [ 4.251019] ** ** [ 4.251020] ** trace_printk() being used. Allocating extra memory. ** [ 4.251021] ** ** [ 4.251021] ** This means that this is a DEBUG kernel and it is ** [ 4.251022] ** unsafe for produciton use. ** [ 4.251023] ** ** [ 4.251024] ** If you see this message and you are not debugging ** [ 4.251024] ** the kernel, report this immediately to your vendor! ** [ 4.251025] ** ** [ 4.251026] ** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE ** [ 4.251027] ********************************************************** [ 4.375162] [drm] Memory usable by graphics device = 2048M [ 4.382963] [drm] Replacing VGA console driver [ 4.390710] checking generic (d0000000 7ff0000) vs hw (d0000000 10000000) [ 4.398617] fb: switching to inteldrmfb from VESA VGA [ 4.406578] Console: switching to colour dummy device 80x25 [ 4.432283] i915 0000:00:02.0: irq 29 for MSI/MSI-X [ 4.432327] [drm] Supports vblank timestamp caching Rev 2 (21.10.2013). [ 4.432335] [drm] Driver supports precise vblank timestamp query. [ 4.432437] vgaarb: device changed decodes: PCI:0000:00:02.0,olddecodes=io+mem,decodes=io+mem:owns=io+mem [ 4.521746] BUG: unable to handle kernel paging request at ffffc900108c4000 [ 4.521781] IP: [<ffffffffa014323d>] gen4_read32+0x3d/0xc0 [i915] [ 4.521843] PGD 13f021067 PUD 13f022067 PMD 136193067 PTE 0 [ 4.521860] Oops: 0000 [#1] SMP [ 4.521872] Dumping ftrace buffer: [ 4.521880] --------------------------------- [ 4.521936] udevd-120 1d.h. 4672095us : i9xx_hpd_irq_handler: PIN 1 continue [ 4.521987] udevd-120 1d.h. 4672097us : i9xx_hpd_irq_handler: PIN 2 continue [ 4.522036] udevd-120 1d.h. 4672098us : i9xx_hpd_irq_handler: PIN 3 continue [ 4.522085] udevd-120 1d.h. 4672099us : i9xx_hpd_irq_handler: PIN 4 continue [ 4.522134] udevd-120 1d.h. 4672099us : i9xx_hpd_irq_handler: PIN 5 continue [ 4.522183] udevd-120 1d.h. 4672100us : i9xx_hpd_irq_handler: PORT 3 PIN 6 continue [ 4.522233] udevd-120 1d.h. 4672101us : i9xx_hpd_irq_handler: PORT 3 PIN 6 sets queue_dig = true [ 4.522283] udevd-120 1d.h. 4672102us : i9xx_hpd_irq_handler: QUEUE [ 4.522331] <...>-6 0.... 4672125us : i915_digport_work_func: WORK [ 4.522339] --------------------------------- [ 4.522345] Modules linked in: i915(+) drm_kms_helper drm i2c_algo_bit thermal video processor thermal_sys button scsi_dh_rdac scsi_dh_alua scsi_dh_emc scsi_dh_hp_sw scsi_dh netconsole atl1c [ 4.522401] CPU: 0 PID: 6 Comm: kworker/u4:0 Not tainted 3.17.0-bisect #222 [ 4.522408] Hardware name: TOSHIBA SATELLITE T130/SATELLITE T130, BIOS V1.70 09/29/2009 [ 4.522453] Workqueue: i915-dp i915_digport_work_func [i915] [ 4.522462] task: ffff88013f166150 ti: ffff88013f168000 task.ti: ffff88013f168000 [ 4.522470] RIP: 0010:[<ffffffffa014323d>] [<ffffffffa014323d>] gen4_read32+0x3d/0xc0 [i915] [ 4.522520] RSP: 0018:ffff88013f16bd48 EFLAGS: 00010086 [ 4.522527] RAX: 0000000000000297 RBX: ffff88013b1f0000 RCX: 00000000000000da [ 4.522533] RDX: ffffc900108c4000 RSI: ffff88013b1f93c8 RDI: ffff88013b1f0068 [ 4.522540] RBP: ffff88013f16bd70 R08: 0000000000000001 R09: 0000000000000024 [ 4.522547] R10: 00000001167af8eb R11: 0000000000000006 R12: 00000000000c4000 [ 4.522553] R13: ffff88013b1f0068 R14: 0000000000000001 R15: 0000000000000001 [ 4.522560] FS: 0000000000000000(0000) GS:ffff88013fc00000(0000) knlGS:0000000000000000 [ 4.522568] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b [ 4.522575] CR2: ffffc900108c4000 CR3: 0000000001a15000 CR4: 00000000000407f0 [ 4.522581] Stack: [ 4.522586] 0000000000800000 0000000000000011 ffff88013584e000 0000000000000001 [ 4.522601] ffff880036c92000 ffff88013f16bd88 ffffffffa01537b3 ffff88013b1f0000 [ 4.522617] ffff88013f16bdc8 ffffffffa0179a73 ffff880036c920e0 ffff88013b1f9400 [ 4.522632] Call Trace: [ 4.522681] [<ffffffffa01537b3>] ibx_digital_port_connected+0x63/0xb0 [i915] [ 4.522733] [<ffffffffa0179a73>] intel_dp_hpd_pulse+0xc3/0x1f0 [i915] [ 4.522777] [<ffffffffa0131d60>] i915_digport_work_func+0xb0/0x130 [i915] [ 4.522789] [<ffffffff81060b26>] process_one_work+0x186/0x3f0 [ 4.522797] [<ffffffff81060eb1>] worker_thread+0x121/0x480 [ 4.522806] [<ffffffff81060d90>] ? process_one_work+0x3f0/0x3f0 [ 4.522815] [<ffffffff81065689>] kthread+0xc9/0xe0 [ 4.522824] [<ffffffff810655c0>] ? kthread_create_on_node+0x170/0x170 [ 4.522834] [<ffffffff8157edac>] ret_from_fork+0x7c/0xb0 [ 4.522843] [<ffffffff810655c0>] ? kthread_create_on_node+0x170/0x170 [ 4.522849] Code: 41 54 49 89 f4 53 48 8d b7 c8 93 00 00 48 89 fb 48 8b 3f 4c 8d 6b 68 e8 f2 f1 ff ff 4c 89 ef e8 4a b7 43 e1 4c 89 e2 48 03 53 60 <44> 8b 32 48 89 c6 4c 89 ef e8 a5 b3 43 e1 8b 05 f7 0d 08 00 85 [ 4.523001] RIP [<ffffffffa014323d>] gen4_read32+0x3d/0xc0 [i915] [ 4.523050] RSP <ffff88013f16bd48> [ 4.523055] CR2: ffffc900108c4000 [ 4.523064] ---[ end trace 08b04cb79531ee7e ]--- [ 4.523070] Kernel panic - not syncing: Fatal exception [ 4.523096] Dumping ftrace buffer: [ 4.523101] (ftrace buffer empty) [ 4.523109] Kernel Offset: 0x0 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffff9fffffff) [ 4.523118] Rebooting in 10 seconds.. --- drivers/gpu/drm/i915/i915_drv.c | 2 ++ drivers/gpu/drm/i915/i915_irq.c | 11 +++++++++-- 2 files changed, 11 insertions(+), 2 deletions(-)