From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marek Szyprowski Subject: Re: [PATCH] iommu: exynos: pointers are nto physical addresses Date: Mon, 29 Feb 2016 10:33:59 +0100 Message-ID: <56D41087.60506@samsung.com> References: <1456735568-3886545-1-git-send-email-arnd@arndb.de> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-reply-to: <1456735568-3886545-1-git-send-email-arnd-r2nGTMty4D4@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Arnd Bergmann , Joerg Roedel , Joerg Roedel , Kukjin Kim , Krzysztof Kozlowski Cc: iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, linux-samsung-soc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org List-Id: linux-samsung-soc@vger.kernel.org Hi Arnd, On 2016-02-29 09:45, Arnd Bergmann wrote: > The exynos iommu driver changed an incorrect cast from pointer > to 'unsigned int' to an equally incorrect cast to a 'phys_addr_t', > which results in an obvious compile-time error when phys_addr_t > is wider than pointers are: > > drivers/iommu/exynos-iommu.c: In function 'alloc_lv2entry': > drivers/iommu/exynos-iommu.c:918:32: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast] > > The code does not actually want the physical address (which would > involve using virt_to_phys()), but just checks the alignment, > so we can change it to use a cast to uintptr_t instead. > > Signed-off-by: Arnd Bergmann > Fixes: 740a01eee9ad ("iommu/exynos: Add support for v5 SYSMMU") Thanks for this fix. > --- > I also see that some incorrect __raw_writel() calls have crept in > around the same time, which breaks running big-endian kernels when > this driver is loaded. > > Please fix and that that as well. Okay, so in the driver code all __raw_writel should be replaced by writel(), right? Those __raw_writel() calls were there from the beginning and I didn't know that they should not be used in the driver code. > drivers/iommu/exynos-iommu.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c > index b0665042bf29..484b3b37631f 100644 > --- a/drivers/iommu/exynos-iommu.c > +++ b/drivers/iommu/exynos-iommu.c > @@ -915,7 +915,7 @@ static sysmmu_pte_t *alloc_lv2entry(struct exynos_iommu_domain *domain, > bool need_flush_flpd_cache = lv1ent_zero(sent); > > pent = kmem_cache_zalloc(lv2table_kmem_cache, GFP_ATOMIC); > - BUG_ON((phys_addr_t)pent & (LV2TABLE_SIZE - 1)); > + BUG_ON((uintptr_t)pent & (LV2TABLE_SIZE - 1)); > if (!pent) > return ERR_PTR(-ENOMEM); > Best regards -- Marek Szyprowski, PhD Samsung R&D Institute Poland