2023-06-02 02:32:49

by Yanfei Xu

Subject: [PATCH v2 1/2] iommu/vt-d: Handle the failure case of dmar_reenable_qi()

dmar_reenable_qi() may not succeed. Check and return when it fails.

Signed-off-by: Yanfei Xu <[email protected]>
---
drivers/iommu/intel/iommu.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index 8096273b034c..e9188d045609 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -2967,10 +2967,14 @@ static int init_iommu_hw(void)
{
struct dmar_drhd_unit *drhd;
struct intel_iommu *iommu = NULL;
+ int ret;

- for_each_active_iommu(iommu, drhd)
+ for_each_active_iommu(iommu, drhd) {
if (iommu->qi)
- dmar_reenable_qi(iommu);
+ ret = dmar_reenable_qi(iommu);
+ if (ret)
+ return ret;
+ }

for_each_iommu(iommu, drhd) {
if (drhd->ignored) {
--
2.34.1

2023-06-02 09:45:39

by Robin Murphy

Subject: Re: [PATCH v2 1/2] iommu/vt-d: Handle the failure case of dmar_reenable_qi()

On 2023-06-02 03:05, Yanfei Xu wrote:
> dmar_reenable_qi() may not succeed. Check and return when it fails.
>
> Signed-off-by: Yanfei Xu <[email protected]>
> ---
> drivers/iommu/intel/iommu.c | 8 ++++++--
> 1 file changed, 6 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
> index 8096273b034c..e9188d045609 100644
> --- a/drivers/iommu/intel/iommu.c
> +++ b/drivers/iommu/intel/iommu.c
> @@ -2967,10 +2967,14 @@ static int init_iommu_hw(void)
> {
> struct dmar_drhd_unit *drhd;
> struct intel_iommu *iommu = NULL;
> + int ret;
>
> - for_each_active_iommu(iommu, drhd)
> + for_each_active_iommu(iommu, drhd) {
> if (iommu->qi)
> - dmar_reenable_qi(iommu);
> + ret = dmar_reenable_qi(iommu);
> + if (ret)

Nit: either this should be inside the previous condition, or you need to
initialise ret to 0.

Thanks,
Robin.

> + return ret;
> + }
>
> for_each_iommu(iommu, drhd) {
> if (drhd->ignored) {

2023-06-02 10:11:42

by Yanfei Xu

Subject: Re: [PATCH v2 1/2] iommu/vt-d: Handle the failure case of dmar_reenable_qi()

On 6/2/2023 5:27 PM, Robin Murphy wrote:
> On 2023-06-02 03:05, Yanfei Xu wrote:
>> dmar_reenable_qi() may not succeed. Check and return when it fails.
>>
>> Signed-off-by: Yanfei Xu <[email protected]>
>> ---
>>   drivers/iommu/intel/iommu.c | 8 ++++++--
>>   1 file changed, 6 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
>> index 8096273b034c..e9188d045609 100644
>> --- a/drivers/iommu/intel/iommu.c
>> +++ b/drivers/iommu/intel/iommu.c
>> @@ -2967,10 +2967,14 @@ static int init_iommu_hw(void)
>>   {
>>       struct dmar_drhd_unit *drhd;
>>       struct intel_iommu *iommu = NULL;
>> +    int ret;
>>   -    for_each_active_iommu(iommu, drhd)
>> +    for_each_active_iommu(iommu, drhd) {
>>           if (iommu->qi)
>> -            dmar_reenable_qi(iommu);
>> +            ret = dmar_reenable_qi(iommu);
>> +        if (ret)
>
> Nit: either this should be inside the previous condition, or you need
> to initialise ret to 0.
>
Oh, you are right. Will correct it.

Thanks,
Yanfei

> Thanks,
> Robin.
>
>> +            return ret;
>> +    }
>>         for_each_iommu(iommu, drhd) {
>>           if (drhd->ignored) {