On Thu, May 04, 2017 at 12:25:26PM +0200, Takashi Iwai wrote:
On Thu, 04 May 2017 12:18:29 +0200, Chris Wilson wrote:
hdac_wait_for_cmd_dmas() uses a jiffie timeout to ensure that we do not wait forever for stuck hardware. However, it is called from an irq-disabled context which prevents jiffie from advancing and so the loop doesn't terminate if the hardware fails. This can then cause NMI watchdog warnings, such as:
NMI watchdog: Watchdog detected hard LOCKUP on cpu 3 Modules linked in: snd_hda_intel i915 vgem snd_hda_codec_hdmi x86_pkg_temp_thermal intel_powerclamp coretemp crct10dif_pclmul crc32_pclmul snd_hda_codec_realtek snd_hda_codec_generic ghash_clmulni_intel e1000e snd_hda_codec snd_hwdep snd_hda_core snd_pcm ptp mei_me prime_numbers pps_core mei lpc_ich i2c_hid i2c_designware_platform i2c_designware_core [last unloaded: i915] irq event stamp: 13366 hardirqs last enabled at (13365): [<ffffffff81891a87>] _raw_spin_unlock_irq+0x27/0x50 hardirqs last disabled at (13366): [<ffffffff818918d2>] _raw_spin_lock_irq+0x12/0x50 softirqs last enabled at (12744): [<ffffffff81085c79>] __do_softirq+0x1d9/0x4c0 softirqs last disabled at (12721): [<ffffffff810860d9>] irq_exit+0xa9/0xc0 CPU: 3 PID: 10443 Comm: kworker/u8:11 Tainted: G U 4.11.0-rc4-CI-CI_DRM_319+ #1 Hardware name: /NUC5i5RYB, BIOS RYBDWi35.86A.0362.2017.0118.0940 01/18/2017 Workqueue: events_unbound async_run_entry_fn task: ffff88024cd32740 task.stack: ffffc9000162c000 RIP: 0010:preempt_count_add+0xe/0xc0 RSP: 0018:ffffc9000162fbd8 EFLAGS: 00000082 RAX: 0000000080000001 RBX: 0000000704b96558 RCX: 0000000000000002 RDX: 0000000000000000 RSI: ffffffff81c74f2d RDI: 0000000000000001 RBP: ffffc9000162fc08 R08: 00000000bbcc90cc R09: 23c7b07100000000 R10: ffffffff827901a8 R11: ffff88024cd32740 R12: 0000000704b92baa R13: 0000000000003ea0 R14: 0000000000000003 R15: ffffffffa00061f0 FS: 0000000000000000(0000) GS:ffff880256d80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f90f84a5144 CR3: 0000000003e0f000 CR4: 00000000003406e0 Call Trace: ? delay_tsc+0x3d/0xc0 __delay+0xa/0x10 __const_udelay+0x31/0x40 snd_hdac_bus_stop_cmd_io+0x96/0xe0 [snd_hda_core] ? azx_dev_disconnect+0x20/0x20 [snd_hda_intel] snd_hdac_bus_stop_chip+0xb1/0x100 [snd_hda_core] azx_stop_chip+0x9/0x10 [snd_hda_codec] azx_suspend+0x72/0x220 [snd_hda_intel] pci_pm_suspend+0x71/0x140 dpm_run_callback+0x6f/0x330 ? pci_pm_freeze+0xe0/0xe0 __device_suspend+0xf9/0x370 ? dpm_watchdog_set+0x60/0x60 async_suspend+0x1a/0x90 async_run_entry_fn+0x34/0x160 process_one_work+0x1f4/0x6d0 ? process_one_work+0x16e/0x6d0 worker_thread+0x49/0x4a0 kthread+0x107/0x140 ? process_one_work+0x6d0/0x6d0 ? kthread_create_on_node+0x40/0x40 ret_from_fork+0x2e/0x40Fixes: 38b19ed7f81e ("ALSA: hda: fix to wait for RIRB & CORB DMA to set") Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=100419 Signed-off-by: Chris Wilson chris@chris-wilson.co.uk Cc: Jeeja KP jeeja.kp@intel.com Cc: Vinod Koul vinod.koul@intel.com Cc: Takashi Iwai tiwai@suse.de Cc: stable@vger.kernel.org # v4.7+
Any reason to submit a different fix from what's attached in the bugzilla you mentioned?
probably a race between then :)
Jeeja talked to me earlier today and uploaded the patch where we drop the locks and still use jiffies.
Takashi, Do you prefer dropping locks or using loop?
sound/hda/hdac_controller.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/sound/hda/hdac_controller.c b/sound/hda/hdac_controller.c index ee08c389b4d6..7f8806b03982 100644 --- a/sound/hda/hdac_controller.c +++ b/sound/hda/hdac_controller.c @@ -85,14 +85,14 @@ static void hdac_wait_for_cmd_dmas(struct hdac_bus *bus) { unsigned long timeout;
- timeout = jiffies + msecs_to_jiffies(100);
- timeout = 100 * 100; /* 100ms */ while ((snd_hdac_chip_readb(bus, RIRBCTL) & AZX_RBCTL_DMA_EN)
&& time_before(jiffies, timeout))
&& timeout--)
- timeout = jiffies + msecs_to_jiffies(100);
- timeout = 100 * 100; /* 100ms */ while ((snd_hdac_chip_readb(bus, CORBCTL) & AZX_CORBCTL_RUN)
&& time_before(jiffies, timeout))
&& timeout--)}
-- 2.11.0