/* * sound/oss/sb_midi.c * * The low level driver for the Sound Blaster DS chips. * * * Copyright (C) by Hannu Savolainen 1993-1997 * * OSS/Free for Linux is distributed under the GNU GENERAL PUBLIC LICENSE (GPL) * Version 2 (June 1991). See the "COPYING" file distributed with this software * for more info. */ #include #include #include "sound_config.h" #include "sb.h" #undef SB_TEST_IRQ /* * The DSP channel can be used either for input or output. Variable * 'sb_irq_mode' will be set when the program calls read or write first time * after open. Current version doesn't support mode changes without closing * and reopening the device. Support for this feature may be implemented in a * future version of this driver. */ static int sb_midi_open(int dev, int mode, void (*input) (int dev, unsigned char data), void (*output) (int dev) ) { sb_devc *devc = midi_devs[dev]->devc; unsigned long flags; if (devc == NULL) return -ENXIO; spin_lock_irqsave(&devc->lock, flags); if (devc->opened) { spin_unlock_irqrestore(&devc->lock, flags); return -EBUSY; } devc->opened = 1; spin_unlock_irqrestore(&devc->lock, flags); devc->irq_mode = IMODE_MIDI; devc->midi_broken = 0; sb_dsp_reset(devc); if (!sb_dsp_command(devc, 0x35)) /* Start MIDI UART mode */ { devc->opened = 0; return -EIO; } devc->intr_active = 1; if (mode & OPEN_READ) { devc->input_opened = 1; devc->midi_input_intr = input; } return 0; } static void sb_midi_close(int dev) { sb_devc *devc = midi_devs[dev]->devc; unsigned long flags; if (devc == NULL) return; spin_lock_irqsave(&devc->lock, flags); sb_dsp_reset(devc); devc->intr_active = 0; devc->input_opened = 0; devc->opened = 0; spin_unlock_irqrestore(&devc->lock, flags); } static int sb_midi_out(int dev, unsigned char midi_byte) { sb_devc *devc = midi_devs[dev]->devc; if (devc == NULL) return 1; if (devc->midi_broken) return 1; if (!sb_dsp_command(devc, midi_byte)) { devc->midi_broken = 1; return 1; } return 1; } static int sb_midi_start_read(int dev) { return 0; } static int sb_midi_end_read(int dev) { sb_devc *devc = midi_devs[dev]->devc; if (devc == NULL) return -ENXIO; sb_dsp_reset(devc); devc->intr_active = 0; return 0; } static int sb_midi_ioctl(int dev, unsigned cmd, void __user *arg) { return -EINVAL; } void sb_midi_interrupt(sb_devc * devc) { unsigned long flags; unsigned char data; if (devc == NULL) return; spin_lock_irqsave(&devc->lock, flags); data = inb(DSP_READ); if (devc->input_opened) devc->midi_input_intr(devc->my_mididev, data); spin_unlock_irqrestore(&devc->lock, flags); } #define MIDI_SYNTH_NAME "Sound Blaster Midi" #define MIDI_SYNTH_CAPS 0 #include "midi_synth.h" static struct midi_operations sb_midi_operations = { .owner = THIS_MODULE, .info = {"Sound Blaster", 0, 0, SNDCARD_SB}, .converter = &std_midi_synth, .in_info = {0}, .open = sb_midi_open, .close = sb_midi_close, .ioctl = sb_midi_ioctl, .outputc = sb_midi_out, .start_read = sb_midi_start_read, .end_read = sb_midi_end_read, }; void sb_dsp_midi_init(sb_devc * devc, struct module *owner) { int dev; if (devc->model < 2) /* No MIDI support for SB 1.x */ return; dev = sound_alloc_mididev(); if (dev == -1) { printk(KERN_ERR "sb_midi: too many MIDI devices detected\n"); return; } std_midi_synth.midi_dev = devc->my_mididev = dev; midi_devs[dev] = kmalloc(sizeof(struct midi_operations), GFP_KERNEL); if (midi_devs[dev] == NULL) { printk(KERN_WARNING "Sound Blaster: failed to allocate MIDI memory.\n"); sound_unload_mididev(dev); return; } memcpy((char *) midi_devs[dev], (char *) &sb_midi_operations, sizeof(struct midi_operations)); if (owner) midi_devs[dev]->owner = owner; midi_devs[dev]->devc = devc; midi_devs[dev]->converter = kmalloc(sizeof(struct synth_operations), GFP_KERNEL); if (midi_devs[dev]->converter == NULL) { printk(KERN_WARNING "Sound Blaster: failed to allocate MIDI memory.\n"); kfree(midi_devs[dev]); sound_unload_mididev(dev); return; } memcpy((char *) midi_devs[dev]->converter, (char *) &std_midi_synth, sizeof(struct synth_operations)); midi_devs[dev]->converter->id = "SBMIDI"; sequencer_init(); } value='25'>25space:mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2017-01-29 13:50:06 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2017-01-29 13:50:06 -0800
commit39cb2c9a316e77f6dfba96c543e55b6672d5a37e (patch)
tree98fe974ee4e20121253de7f61fc8d01bdb3821c1 /sound/pci/oxygen/oxygen.c
parent2c5d9555d6d937966d79d4c6529a5f7b9206e405 (diff)
drm/i915: Check for NULL i915_vma in intel_unpin_fb_obj()
I've seen this trigger twice now, where the i915_gem_object_to_ggtt() call in intel_unpin_fb_obj() returns NULL, resulting in an oops immediately afterwards as the (inlined) call to i915_vma_unpin_fence() tries to dereference it. It seems to be some race condition where the object is going away at shutdown time, since both times happened when shutting down the X server. The call chains were different: - VT ioctl(KDSETMODE, KD_TEXT): intel_cleanup_plane_fb+0x5b/0xa0 [i915] drm_atomic_helper_cleanup_planes+0x6f/0x90 [drm_kms_helper] intel_atomic_commit_tail+0x749/0xfe0 [i915] intel_atomic_commit+0x3cb/0x4f0 [i915] drm_atomic_commit+0x4b/0x50 [drm] restore_fbdev_mode+0x14c/0x2a0 [drm_kms_helper] drm_fb_helper_restore_fbdev_mode_unlocked+0x34/0x80 [drm_kms_helper] drm_fb_helper_set_par+0x2d/0x60 [drm_kms_helper] intel_fbdev_set_par+0x18/0x70 [i915] fb_set_var+0x236/0x460 fbcon_blank+0x30f/0x350 do_unblank_screen+0xd2/0x1a0 vt_ioctl+0x507/0x12a0 tty_ioctl+0x355/0xc30 do_vfs_ioctl+0xa3/0x5e0 SyS_ioctl+0x79/0x90 entry_SYSCALL_64_fastpath+0x13/0x94 - i915 unpin_work workqueue: intel_unpin_work_fn+0x58/0x140 [i915] process_one_work+0x1f1/0x480 worker_thread+0x48/0x4d0 kthread+0x101/0x140 and this patch purely papers over the issue by adding a NULL pointer check and a WARN_ON_ONCE() to avoid the oops that would then generally make the machine unresponsive. Other callers of i915_gem_object_to_ggtt() seem to also check for the returned pointer being NULL and warn about it, so this clearly has happened before in other places. [ Reported it originally to the i915 developers on Jan 8, applying the ugly workaround on my own now after triggering the problem for the second time with no feedback. This is likely to be the same bug reported as https://bugs.freedesktop.org/show_bug.cgi?id=98829 https://bugs.freedesktop.org/show_bug.cgi?id=99134 which has a patch for the underlying problem, but it hasn't gotten to me, so I'm applying the workaround. ] Cc: Daniel Vetter <daniel.vetter@intel.com> Cc: Jani Nikula <jani.nikula@linux.intel.com> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Cc: Imre Deak <imre.deak@intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'sound/pci/oxygen/oxygen.c')