From mboxrd@z Thu Jan 1 00:00:00 1970 From: s-anna@ti.com (Suman Anna) Date: Tue, 13 Mar 2018 10:47:08 -0500 Subject: [PATCH] media: omap3isp: fix unbalanced dma_iommu_mapping In-Reply-To: <20180313111407.egptbq5vbkny5q4d@valkosipuli.retiisi.org.uk> References: <20180312165207.12436-1-s-anna@ti.com> <20180313111407.egptbq5vbkny5q4d@valkosipuli.retiisi.org.uk> Message-ID: <5c3f99e2-001b-b80a-f840-bc3201addc93@ti.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org 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 >> Signed-off-by: Suman Anna >> Tested-by: Pavel Machek >> --- >> 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 > >> } >> >> return 0; >> >> +error_attach: >> + arm_iommu_release_mapping(isp->mapping); >> + isp->mapping = NULL; >> error: >> - isp_detach_iommu(isp); >> return ret; >> } >> >> >