[PATCH] iommu/msm: Fix error handling in msm_iommu_unmap()

[PATCH] iommu/msm: Fix error handling in msm_iommu_unmap()

[Joerg Roedel]

Error handling in msm_iommu_unmap() is broken. On some error
conditions retval is set to a non-zero value which causes
the function to return 'len' at the end. This hides the
error from the user. Zero should be returned in those error
cases.

Cc: David Brown <davidb@codeaurora.org>
Cc: Stepan Moskovchenko <stepanm@codeaurora.org>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
---
 drivers/iommu/msm_iommu.c |    7 +------
 1 files changed, 1 insertions(+), 6 deletions(-)

diff --git a/drivers/iommu/msm_iommu.c b/drivers/iommu/msm_iommu.c
index 08a90b8..cee307e 100644
--- a/drivers/iommu/msm_iommu.c
+++ b/drivers/iommu/msm_iommu.c
@@ -482,23 +482,19 @@ static size_t msm_iommu_unmap(struct iommu_domain *domain, unsigned long va,
 
 	priv = domain->priv;
 
-	if (!priv) {
-		ret = -ENODEV;
+	if (!priv)
 		goto fail;
-	}
 
 	fl_table = priv->pgtable;
 
 	if (len != SZ_16M && len != SZ_1M &&
 	    len != SZ_64K && len != SZ_4K) {
 		pr_debug("Bad length: %d\n", len);
-		ret = -EINVAL;
 		goto fail;
 	}
 
 	if (!fl_table) {
 		pr_debug("Null page table\n");
-		ret = -EINVAL;
 		goto fail;
 	}
 
@@ -507,7 +503,6 @@ static size_t msm_iommu_unmap(struct iommu_domain *domain, unsigned long va,
 
 	if (*fl_pte == 0) {
 		pr_debug("First level PTE is 0\n");
-		ret = -ENODEV;
 		goto fail;
 	}
 
-- 
1.7.5.4

Re: [PATCH] iommu/msm: Fix error handling in msm_iommu_unmap()

[David Brown]

On Thu, Jan 26, 2012 at 06:29:44PM +0100, Joerg Roedel wrote:
> Error handling in msm_iommu_unmap() is broken. On some error
> conditions retval is set to a non-zero value which causes
> the function to return 'len' at the end. This hides the
> error from the user. Zero should be returned in those error
> cases.
> 
> Cc: David Brown <davidb@codeaurora.org>
> Cc: Stepan Moskovchenko <stepanm@codeaurora.org>
> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
> ---
>  drivers/iommu/msm_iommu.c |    7 +------
>  1 files changed, 1 insertions(+), 6 deletions(-)

Acked-by: David Brown <davidb@codeaurora.org>

-- 
Sent by an employee of the Qualcomm Innovation Center, Inc.
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum.

Re: [PATCH] iommu/msm: Fix error handling in msm_iommu_unmap()

[Joerg Roedel]

On Thu, Jan 26, 2012 at 04:06:30PM -0800, David Brown wrote:
> On Thu, Jan 26, 2012 at 06:29:44PM +0100, Joerg Roedel wrote:
> > Error handling in msm_iommu_unmap() is broken. On some error
> > conditions retval is set to a non-zero value which causes
> > the function to return 'len' at the end. This hides the
> > error from the user. Zero should be returned in those error
> > cases.
> > 
> > Cc: David Brown <davidb@codeaurora.org>
> > Cc: Stepan Moskovchenko <stepanm@codeaurora.org>
> > Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
> > ---
> >  drivers/iommu/msm_iommu.c |    7 +------
> >  1 files changed, 1 insertions(+), 6 deletions(-)
> 
> Acked-by: David Brown <davidb@codeaurora.org>

Thanks. I'll queue this up with iommu fixes for 3.3 and mark it for
stable as well.


	Joerg

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