[PATCH] ALSA: emu10k1: Stop using iommu_present()
iommu_get_domain_for_dev() is already perfectly happy to return NULL if the given device has no IOMMU. Drop the unnecessary check.
Signed-off-by: Robin Murphy robin.murphy@arm.com --- sound/pci/emu10k1/emu10k1_main.c | 3 --- 1 file changed, 3 deletions(-)
diff --git a/sound/pci/emu10k1/emu10k1_main.c b/sound/pci/emu10k1/emu10k1_main.c index 86cc1ca025e4..5ffab343b89c 100644 --- a/sound/pci/emu10k1/emu10k1_main.c +++ b/sound/pci/emu10k1/emu10k1_main.c @@ -1751,9 +1751,6 @@ static void snd_emu10k1_detect_iommu(struct snd_emu10k1 *emu)
emu->iommu_workaround = false;
- if (!iommu_present(emu->card->dev->bus)) - return; - domain = iommu_get_domain_for_dev(emu->card->dev); if (domain && domain->type == IOMMU_DOMAIN_IDENTITY) return;
On Tue, 05 Apr 2022 14:13:33 +0200, Robin Murphy wrote:
iommu_get_domain_for_dev() is already perfectly happy to return NULL if the given device has no IOMMU. Drop the unnecessary check.
Signed-off-by: Robin Murphy robin.murphy@arm.com
This will change the code behavior. The current code does nothing if no IOMMU is found, but after your removal of the check, the code reaches to emu->iommu_workaround = true incorrectly.
thanks,
Takashi
sound/pci/emu10k1/emu10k1_main.c | 3 --- 1 file changed, 3 deletions(-)
diff --git a/sound/pci/emu10k1/emu10k1_main.c b/sound/pci/emu10k1/emu10k1_main.c index 86cc1ca025e4..5ffab343b89c 100644 --- a/sound/pci/emu10k1/emu10k1_main.c +++ b/sound/pci/emu10k1/emu10k1_main.c @@ -1751,9 +1751,6 @@ static void snd_emu10k1_detect_iommu(struct snd_emu10k1 *emu)
emu->iommu_workaround = false;
- if (!iommu_present(emu->card->dev->bus))
return;- domain = iommu_get_domain_for_dev(emu->card->dev); if (domain && domain->type == IOMMU_DOMAIN_IDENTITY) return;
-- 2.28.0.dirty
On 2022-04-05 13:29, Takashi Iwai wrote:
On Tue, 05 Apr 2022 14:13:33 +0200, Robin Murphy wrote:
iommu_get_domain_for_dev() is already perfectly happy to return NULL if the given device has no IOMMU. Drop the unnecessary check.
Signed-off-by: Robin Murphy robin.murphy@arm.com
This will change the code behavior. The current code does nothing if no IOMMU is found, but after your removal of the check, the code reaches to emu->iommu_workaround = true incorrectly.
Ah, right you are - I should have looked more closely at the second check, where of course "domain &&" wants tweaking to "!domain ||" as well. I'll send a v2 in a bit...
Thanks, Robin.
thanks,
Takashi
sound/pci/emu10k1/emu10k1_main.c | 3 --- 1 file changed, 3 deletions(-)
diff --git a/sound/pci/emu10k1/emu10k1_main.c b/sound/pci/emu10k1/emu10k1_main.c index 86cc1ca025e4..5ffab343b89c 100644 --- a/sound/pci/emu10k1/emu10k1_main.c +++ b/sound/pci/emu10k1/emu10k1_main.c @@ -1751,9 +1751,6 @@ static void snd_emu10k1_detect_iommu(struct snd_emu10k1 *emu)
emu->iommu_workaround = false;
- if (!iommu_present(emu->card->dev->bus))
return;- domain = iommu_get_domain_for_dev(emu->card->dev); if (domain && domain->type == IOMMU_DOMAIN_IDENTITY) return;
-- 2.28.0.dirty
participants (2)
-
Robin Murphy -
Takashi Iwai