]> git.baikalelectronics.ru Git - kernel.git/commit
Revert "ASoC: Intel: Skylake: Acquire irq after RIRB allocation"
authorYu Zhao <yuzhao@google.com>
Tue, 11 Sep 2018 21:12:46 +0000 (15:12 -0600)
committerMark Brown <broonie@kernel.org>
Wed, 12 Sep 2018 10:19:43 +0000 (11:19 +0100)
commit0291bdd7bdb18cdc3b7863e362c1ffb9f97a0d5b
tree48e4c221ab288f56cb309241dbb519b7d671e22c
parent1dd17d3b2fb64607beb2bc92578667bfa33076a9
Revert "ASoC: Intel: Skylake: Acquire irq after RIRB allocation"

This reverts commit a702540176e50ca420156517205effa6e1a3a764.

The patch doesn't fix accessing memory with null pointer in
skl_interrupt().

There are two problems: 1) skl_init_chip() is called twice, before
and after dma buffer is allocate. The first call sets bus->chip_init
which prevents the second from initializing bus->corb.buf and
rirb.buf from bus->rb.area. 2) snd_hdac_bus_init_chip() enables
interrupt before snd_hdac_bus_init_cmd_io() initializing dma buffers.
There is a small window which skl_interrupt() can be called if irq
has been acquired. If so, it crashes when using null dma buffer
pointers.

Will fix the problems in the following patches. Also attaching the
crash for future reference.

[   16.949148] general protection fault: 0000 [#1] PREEMPT SMP KASAN PTI
<snipped>
[   16.950903] Call Trace:
[   16.950906]  <IRQ>
[   16.950918]  skl_interrupt+0x19e/0x2d6 [snd_soc_skl]
[   16.950926]  ? dma_supported+0xb5/0xb5 [snd_soc_skl]
[   16.950933]  __handle_irq_event_percpu+0x27a/0x6c8
[   16.950937]  ? __irq_wake_thread+0x1d1/0x1d1
[   16.950942]  ? __do_softirq+0x57a/0x69e
[   16.950944]  handle_irq_event_percpu+0x95/0x1ba
[   16.950948]  ? _raw_spin_unlock+0x65/0xdc
[   16.950951]  ? __handle_irq_event_percpu+0x6c8/0x6c8
[   16.950953]  ? _raw_spin_unlock+0x65/0xdc
[   16.950957]  ? time_cpufreq_notifier+0x483/0x483
[   16.950959]  handle_irq_event+0x89/0x123
[   16.950962]  handle_fasteoi_irq+0x16f/0x425
[   16.950965]  handle_irq+0x1fe/0x28e
[   16.950969]  do_IRQ+0x6e/0x12e
[   16.950972]  common_interrupt+0x7a/0x7a
[   16.950974]  </IRQ>
<snipped>
[   16.951031] RIP: snd_hdac_bus_update_rirb+0x19b/0x4cf [snd_hda_core] RSP: ffff88015c807c08
[   16.951036] ---[ end trace 58bf9ece1775bc92 ]---

Fixes: 2eeeb4f4733b ("ASoC: Intel: Skylake: Acquire irq after RIRB allocation")
Signed-off-by: Yu Zhao <yuzhao@google.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
sound/soc/intel/skylake/skl.c