From 64a06f195d3b2d65141b32c80d6b7f0db4df6cb5 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Mon, 17 May 2021 15:15:42 +0200 Subject: [PATCH] ALSA: usx2y: Fix shmem initialization Currently us428ctls_shmem pages are allocated dynamically upon the mmap call, but this is quite racy. Since the shared memory itself is mandatory for the mmap, let's allocate it at the beginning of the card initialization. Also, fix the initialization of the wait queue, too. Link: https://lore.kernel.org/r/20210517131545.27252-9-tiwai@suse.de Signed-off-by: Takashi Iwai --- sound/usb/usx2y/usX2Yhwdep.c | 18 +++++++++--------- sound/usb/usx2y/usbusx2y.c | 1 + 2 files changed, 10 insertions(+), 9 deletions(-) diff --git a/sound/usb/usx2y/usX2Yhwdep.c b/sound/usb/usx2y/usX2Yhwdep.c index ec7e3beed4f9..c29da0341bc5 100644 --- a/sound/usb/usx2y/usX2Yhwdep.c +++ b/sound/usb/usx2y/usX2Yhwdep.c @@ -60,14 +60,6 @@ static int snd_us428ctls_mmap(struct snd_hwdep *hw, struct file *filp, struct vm return -EINVAL; } - if (!us428->us428ctls_sharedmem) { - init_waitqueue_head(&us428->us428ctls_wait_queue_head); - us428->us428ctls_sharedmem = alloc_pages_exact(US428_SHAREDMEM_PAGES, GFP_KERNEL); - if (!us428->us428ctls_sharedmem) - return -ENOMEM; - memset(us428->us428ctls_sharedmem, -1, US428_SHAREDMEM_PAGES); - us428->us428ctls_sharedmem->ctl_snapshot_last = -2; - } area->vm_ops = &us428ctls_vm_ops; area->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP; area->vm_private_data = hw->private_data; @@ -232,18 +224,26 @@ int usx2y_hwdep_new(struct snd_card *card, struct usb_device *device) { int err; struct snd_hwdep *hw; + struct usx2ydev *us428 = usx2y(card); err = snd_hwdep_new(card, SND_USX2Y_LOADER_ID, 0, &hw); if (err < 0) return err; hw->iface = SNDRV_HWDEP_IFACE_USX2Y; - hw->private_data = usx2y(card); + hw->private_data = us428; hw->ops.dsp_status = snd_usx2y_hwdep_dsp_status; hw->ops.dsp_load = snd_usx2y_hwdep_dsp_load; hw->ops.mmap = snd_us428ctls_mmap; hw->ops.poll = snd_us428ctls_poll; hw->exclusive = 1; sprintf(hw->name, "/dev/bus/usb/%03d/%03d", device->bus->busnum, device->devnum); + + us428->us428ctls_sharedmem = alloc_pages_exact(US428_SHAREDMEM_PAGES, GFP_KERNEL); + if (!us428->us428ctls_sharedmem) + return -ENOMEM; + memset(us428->us428ctls_sharedmem, -1, US428_SHAREDMEM_PAGES); + us428->us428ctls_sharedmem->ctl_snapshot_last = -2; + return 0; } diff --git a/sound/usb/usx2y/usbusx2y.c b/sound/usb/usx2y/usbusx2y.c index d2e1cf163521..09ead00e395e 100644 --- a/sound/usb/usx2y/usbusx2y.c +++ b/sound/usb/usx2y/usbusx2y.c @@ -375,6 +375,7 @@ static int usx2y_create_card(struct usb_device *device, card->private_free = snd_usx2y_card_private_free; usx2y(card)->dev = device; init_waitqueue_head(&usx2y(card)->prepare_wait_queue); + init_waitqueue_head(&usx2y(card)->us428ctls_wait_queue_head); mutex_init(&usx2y(card)->pcm_mutex); INIT_LIST_HEAD(&usx2y(card)->midi_list); strcpy(card->driver, "USB "NAME_ALLCAPS""); -- 2.11.0