Messages in this thread Patch in this message | | | From | Greg Kroah-Hartman <> | Subject | [PATCH 4.19 67/91] ALSA: firewire: Clean up a locking issue in copy_resp_to_buf() | Date | Mon, 23 Nov 2020 13:22:27 +0100 |
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From: Dan Carpenter <dan.carpenter@oracle.com>
commit 02a9c6ee4183af2e438454c55098b828a96085fb upstream.
The spin_lock/unlock_irq() functions cannot be nested. The problem is that presumably we would want the IRQs to be re-enabled on the second call the spin_unlock_irq() but instead it will be enabled at the first call so IRQs will be enabled earlier than expected.
In this situation the copy_resp_to_buf() function is only called from one function and it is called with IRQs disabled. We can just use the regular spin_lock/unlock() functions.
Fixes: 555e8a8f7f14 ("ALSA: fireworks: Add command/response functionality into hwdep interface") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Cc: <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20201113101241.GB168908@mwanda Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
--- sound/firewire/fireworks/fireworks_transaction.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
--- a/sound/firewire/fireworks/fireworks_transaction.c +++ b/sound/firewire/fireworks/fireworks_transaction.c @@ -124,7 +124,7 @@ copy_resp_to_buf(struct snd_efw *efw, vo t = (struct snd_efw_transaction *)data; length = min_t(size_t, be32_to_cpu(t->length) * sizeof(u32), length); - spin_lock_irq(&efw->lock); + spin_lock(&efw->lock); if (efw->push_ptr < efw->pull_ptr) capacity = (unsigned int)(efw->pull_ptr - efw->push_ptr); @@ -191,7 +191,7 @@ handle_resp_for_user(struct fw_card *car copy_resp_to_buf(efw, data, length, rcode); end: - spin_unlock_irq(&instances_lock); + spin_unlock(&instances_lock); } static void
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