| Message ID | 20180312165207.12436-1-s-anna@ti.com |
|---|---|
| State | New |
| Headers | show |
| Series | media: omap3isp: fix unbalanced dma_iommu_mapping | expand |
Hi Sakari, On 03/13/2018 06:14 AM, Sakari Ailus wrote: > Hi Suman, > > Thanks for the patch. > > On Mon, Mar 12, 2018 at 11:52:07AM -0500, Suman Anna wrote: >> The OMAP3 ISP driver manages its MMU mappings through the IOMMU-aware >> ARM DMA backend. The current code creates a dma_iommu_mapping and >> attaches this to the ISP device, but never detaches the mapping in >> either the probe failure paths or the driver remove path resulting >> in an unbalanced mapping refcount and a memory leak. Fix this properly. >> >> Reported-by: Pavel Machek <pavel@ucw.cz> >> Signed-off-by: Suman Anna <s-anna@ti.com> >> Tested-by: Pavel Machek <pavel@ucw.cz> >> --- >> Hi Mauro, Laurent, >> >> This fixes an issue reported by Pavel and discussed on this >> thread, >> https://marc.info/?l=linux-omap&m=152051945803598&w=2 >> >> Posting this again to the appropriate lists. >> >> regards >> Suman >> >> drivers/media/platform/omap3isp/isp.c | 7 +++++-- >> 1 file changed, 5 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/media/platform/omap3isp/isp.c b/drivers/media/platform/omap3isp/isp.c >> index 8eb000e3d8fd..c7d667bfc2af 100644 >> --- a/drivers/media/platform/omap3isp/isp.c >> +++ b/drivers/media/platform/omap3isp/isp.c >> @@ -1945,6 +1945,7 @@ static int isp_initialize_modules(struct isp_device *isp) >> >> static void isp_detach_iommu(struct isp_device *isp) >> { >> + arm_iommu_detach_device(isp->dev); >> arm_iommu_release_mapping(isp->mapping); >> isp->mapping = NULL; >> } >> @@ -1971,13 +1972,15 @@ static int isp_attach_iommu(struct isp_device *isp) >> ret = arm_iommu_attach_device(isp->dev, mapping); >> if (ret < 0) { >> dev_err(isp->dev, "failed to attach device to VA mapping\n"); >> - goto error; >> + goto error_attach; > > Instead of changing the label here, could you return immediately where the > previous point of error handling is? No need to add another label. Yeah, I debated about this while doing the patch, and chose to retain the previous common return on the error paths. There are only 2 error paths, so didn't want to mix them up. If you still prefer the mixed style, I can post a v2. regards Suman > > After fixing that you can add: > > Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com> > >> } >> >> return 0; >> >> +error_attach: >> + arm_iommu_release_mapping(isp->mapping); >> + isp->mapping = NULL; >> error: >> - isp_detach_iommu(isp); >> return ret; >> } >> >> >
On Tue, Mar 13, 2018 at 10:47:08AM -0500, Suman Anna wrote: > Hi Sakari, > > On 03/13/2018 06:14 AM, Sakari Ailus wrote: > > Hi Suman, > > > > Thanks for the patch. > > > > On Mon, Mar 12, 2018 at 11:52:07AM -0500, Suman Anna wrote: > >> The OMAP3 ISP driver manages its MMU mappings through the IOMMU-aware > >> ARM DMA backend. The current code creates a dma_iommu_mapping and > >> attaches this to the ISP device, but never detaches the mapping in > >> either the probe failure paths or the driver remove path resulting > >> in an unbalanced mapping refcount and a memory leak. Fix this properly. > >> > >> Reported-by: Pavel Machek <pavel@ucw.cz> > >> Signed-off-by: Suman Anna <s-anna@ti.com> > >> Tested-by: Pavel Machek <pavel@ucw.cz> > >> --- > >> Hi Mauro, Laurent, > >> > >> This fixes an issue reported by Pavel and discussed on this > >> thread, > >> https://marc.info/?l=linux-omap&m=152051945803598&w=2 > >> > >> Posting this again to the appropriate lists. > >> > >> regards > >> Suman > >> > >> drivers/media/platform/omap3isp/isp.c | 7 +++++-- > >> 1 file changed, 5 insertions(+), 2 deletions(-) > >> > >> diff --git a/drivers/media/platform/omap3isp/isp.c b/drivers/media/platform/omap3isp/isp.c > >> index 8eb000e3d8fd..c7d667bfc2af 100644 > >> --- a/drivers/media/platform/omap3isp/isp.c > >> +++ b/drivers/media/platform/omap3isp/isp.c > >> @@ -1945,6 +1945,7 @@ static int isp_initialize_modules(struct isp_device *isp) > >> > >> static void isp_detach_iommu(struct isp_device *isp) > >> { > >> + arm_iommu_detach_device(isp->dev); > >> arm_iommu_release_mapping(isp->mapping); > >> isp->mapping = NULL; > >> } > >> @@ -1971,13 +1972,15 @@ static int isp_attach_iommu(struct isp_device *isp) > >> ret = arm_iommu_attach_device(isp->dev, mapping); > >> if (ret < 0) { > >> dev_err(isp->dev, "failed to attach device to VA mapping\n"); > >> - goto error; > >> + goto error_attach; > > > > Instead of changing the label here, could you return immediately where the > > previous point of error handling is? No need to add another label. > > Yeah, I debated about this while doing the patch, and chose to retain > the previous common return on the error paths. There are only 2 error > paths, so didn't want to mix them up. If you still prefer the mixed > style, I can post a v2. Yes, please. In general if you only need return a value, a label isn't needed for that even if goto + labels would be otherwise used for error handling. -- Sakari Ailus e-mail: sakari.ailus@iki.fi
diff --git a/drivers/media/platform/omap3isp/isp.c b/drivers/media/platform/omap3isp/isp.c index 8eb000e3d8fd..c7d667bfc2af 100644 --- a/drivers/media/platform/omap3isp/isp.c +++ b/drivers/media/platform/omap3isp/isp.c @@ -1945,6 +1945,7 @@ static int isp_initialize_modules(struct isp_device *isp) static void isp_detach_iommu(struct isp_device *isp) { + arm_iommu_detach_device(isp->dev); arm_iommu_release_mapping(isp->mapping); isp->mapping = NULL; } @@ -1971,13 +1972,15 @@ static int isp_attach_iommu(struct isp_device *isp) ret = arm_iommu_attach_device(isp->dev, mapping); if (ret < 0) { dev_err(isp->dev, "failed to attach device to VA mapping\n"); - goto error; + goto error_attach; } return 0; +error_attach: + arm_iommu_release_mapping(isp->mapping); + isp->mapping = NULL; error: - isp_detach_iommu(isp); return ret; }