From mboxrd@z Thu Jan 1 00:00:00 1970 From: Konrad Rzeszutek Wilk Subject: Re: [PATCH] drm/ttm: dma: Don't crash on memory in the vmalloc range Date: Fri, 15 May 2015 15:55:51 -0400 Message-ID: <20150515195551.GE23819@l.oracle.com> References: <1431673794-16169-1-git-send-email-acourbot@nvidia.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: Received: from userp1040.oracle.com (userp1040.oracle.com [156.151.31.81]) by gabe.freedesktop.org (Postfix) with ESMTP id E87386EA7F for ; Fri, 15 May 2015 12:56:03 -0700 (PDT) Content-Disposition: inline In-Reply-To: <1431673794-16169-1-git-send-email-acourbot@nvidia.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" To: Alexandre Courbot Cc: gnurou@gmail.com, Thomas Hellstrom , Arnd Bergmann , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org List-Id: dri-devel@lists.freedesktop.org T24gRnJpLCBNYXkgMTUsIDIwMTUgYXQgMDQ6MDk6NTRQTSArMDkwMCwgQWxleGFuZHJlIENvdXJi b3Qgd3JvdGU6Cj4gZG1hX2FsbG9jX2NvaGVyZW50KCkgY2FuIHJldHVybiBtZW1vcnkgaW4gdGhl IHZtYWxsb2MgcmFuZ2UuCj4gdmlydF90b19wYWdlKCkgY2Fubm90IGhhbmRsZSBzdWNoIGFkZHJl c3NlcyBhbmQgY3Jhc2hlcy4gVGhpcwo+IHBhdGNoIGRldGVjdHMgc3VjaCBjYXNlcyBhbmQgb2J0 YWlucyB0aGUgc3RydWN0IHBhZ2UgKiB1c2luZwo+IHZtYWxsb2NfdG9fcGFnZSgpIGluc3RlYWQu Cj4gCj4gU2lnbmVkLW9mZi1ieTogQWxleGFuZHJlIENvdXJib3QgPGFjb3VyYm90QG52aWRpYS5j b20+Cj4gLS0tCj4gVGhpcyBwYXRjaCBpcyBhIGZvbGxvdy11cCBvZiB0aGUgZm9sbG93aW5nIGRp c2N1c3Npb246Cj4gCj4gaHR0cHM6Ly93d3cubWFyYy5pbmZvLz9sPWRyaS1kZXZlbCZtPTE0MTU3 OTU5NTQzMTI1NCZ3PTMKPiAKPiBJdCB3b3JrcyBmb3IgbWUgb24gYm90aCAzMi1iaXQgYW5kIDY0 LWJpdCBUZWdyYSwgc28gSSBhbSBub3QgY29udmluY2VkCj4gdGhhdCBUaGllcnJ5J3MgaW5pdGlh bCBjaGFuZ2UgZnJvbSB2aXJ0X3RvX3BhZ2UoKSB0byBwaHlzX3RvX3BhZ2UoKSBpcwo+IHN0aWxs IHJlcXVpcmVkIC0gVGhpZXJyeSwgY2FuIHlvdSBjb25maXJtIHdoZXRoZXIgeW91ciBwYXRjaCBp cyBzdGlsbAo+IHJlbGV2YW50IGFmdGVyIHRoaXMgb25lPwo+IAo+ICBkcml2ZXJzL2dwdS9kcm0v dHRtL3R0bV9wYWdlX2FsbG9jX2RtYS5jIHwgOSArKysrKystLS0KPiAgMSBmaWxlIGNoYW5nZWQs IDYgaW5zZXJ0aW9ucygrKSwgMyBkZWxldGlvbnMoLSkKPiAKPiBkaWZmIC0tZ2l0IGEvZHJpdmVy cy9ncHUvZHJtL3R0bS90dG1fcGFnZV9hbGxvY19kbWEuYyBiL2RyaXZlcnMvZ3B1L2RybS90dG0v dHRtX3BhZ2VfYWxsb2NfZG1hLmMKPiBpbmRleCAwMWUxZDI3ZWIwNzguLjMwNzdmMTU1NDA5OSAx MDA2NDQKPiAtLS0gYS9kcml2ZXJzL2dwdS9kcm0vdHRtL3R0bV9wYWdlX2FsbG9jX2RtYS5jCj4g KysrIGIvZHJpdmVycy9ncHUvZHJtL3R0bS90dG1fcGFnZV9hbGxvY19kbWEuYwo+IEBAIC0zNDIs OSArMzQyLDEyIEBAIHN0YXRpYyBzdHJ1Y3QgZG1hX3BhZ2UgKl9fdHRtX2RtYV9hbGxvY19wYWdl KHN0cnVjdCBkbWFfcG9vbCAqcG9vbCkKPiAgCWRfcGFnZS0+dmFkZHIgPSBkbWFfYWxsb2NfY29o ZXJlbnQocG9vbC0+ZGV2LCBwb29sLT5zaXplLAo+ICAJCQkJCSAgICZkX3BhZ2UtPmRtYSwKPiAg CQkJCQkgICBwb29sLT5nZnBfZmxhZ3MpOwo+IC0JaWYgKGRfcGFnZS0+dmFkZHIpCj4gLQkJZF9w YWdlLT5wID0gdmlydF90b19wYWdlKGRfcGFnZS0+dmFkZHIpOwo+IC0JZWxzZSB7Cj4gKwlpZiAo ZF9wYWdlLT52YWRkcikgewo+ICsJCWlmIChpc192bWFsbG9jX2FkZHIoZF9wYWdlLT52YWRkcikp Cj4gKwkJCWRfcGFnZS0+cCA9IHZtYWxsb2NfdG9fcGFnZShkX3BhZ2UtPnZhZGRyKTsKPiArCQll bHNlCj4gKwkJCWRfcGFnZS0+cCA9IHZpcnRfdG9fcGFnZShkX3BhZ2UtPnZhZGRyKTsKPiArCX0g ZWxzZSB7CgoKTG9va3MgT0sgdG8gbWUuCgo+ICAJCWtmcmVlKGRfcGFnZSk7Cj4gIAkJZF9wYWdl ID0gTlVMTDsKPiAgCX0KPiAtLSAKPiAyLjQuMAo+IApfX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX19fX19fX19fXwpkcmktZGV2ZWwgbWFpbGluZyBsaXN0CmRyaS1kZXZlbEBs aXN0cy5mcmVlZGVza3RvcC5vcmcKaHR0cDovL2xpc3RzLmZyZWVkZXNrdG9wLm9yZy9tYWlsbWFu L2xpc3RpbmZvL2RyaS1kZXZlbAo= From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934772AbbEOT4N (ORCPT ); Fri, 15 May 2015 15:56:13 -0400 Received: from userp1040.oracle.com ([156.151.31.81]:48327 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934313AbbEOT4F (ORCPT ); Fri, 15 May 2015 15:56:05 -0400 Date: Fri, 15 May 2015 15:55:51 -0400 From: Konrad Rzeszutek Wilk To: Alexandre Courbot Cc: Thierry Reding , Thomas Hellstrom , Arnd Bergmann , David Airlie , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, gnurou@gmail.com Subject: Re: [PATCH] drm/ttm: dma: Don't crash on memory in the vmalloc range Message-ID: <20150515195551.GE23819@l.oracle.com> References: <1431673794-16169-1-git-send-email-acourbot@nvidia.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1431673794-16169-1-git-send-email-acourbot@nvidia.com> User-Agent: Mutt/1.5.23 (2014-03-12) X-Source-IP: aserv0021.oracle.com [141.146.126.233] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, May 15, 2015 at 04:09:54PM +0900, Alexandre Courbot wrote: > dma_alloc_coherent() can return memory in the vmalloc range. > virt_to_page() cannot handle such addresses and crashes. This > patch detects such cases and obtains the struct page * using > vmalloc_to_page() instead. > > Signed-off-by: Alexandre Courbot > --- > This patch is a follow-up of the following discussion: > > https://www.marc.info/?l=dri-devel&m=141579595431254&w=3 > > It works for me on both 32-bit and 64-bit Tegra, so I am not convinced > that Thierry's initial change from virt_to_page() to phys_to_page() is > still required - Thierry, can you confirm whether your patch is still > relevant after this one? > > drivers/gpu/drm/ttm/ttm_page_alloc_dma.c | 9 ++++++--- > 1 file changed, 6 insertions(+), 3 deletions(-) > > diff --git a/drivers/gpu/drm/ttm/ttm_page_alloc_dma.c b/drivers/gpu/drm/ttm/ttm_page_alloc_dma.c > index 01e1d27eb078..3077f1554099 100644 > --- a/drivers/gpu/drm/ttm/ttm_page_alloc_dma.c > +++ b/drivers/gpu/drm/ttm/ttm_page_alloc_dma.c > @@ -342,9 +342,12 @@ static struct dma_page *__ttm_dma_alloc_page(struct dma_pool *pool) > d_page->vaddr = dma_alloc_coherent(pool->dev, pool->size, > &d_page->dma, > pool->gfp_flags); > - if (d_page->vaddr) > - d_page->p = virt_to_page(d_page->vaddr); > - else { > + if (d_page->vaddr) { > + if (is_vmalloc_addr(d_page->vaddr)) > + d_page->p = vmalloc_to_page(d_page->vaddr); > + else > + d_page->p = virt_to_page(d_page->vaddr); > + } else { Looks OK to me. > kfree(d_page); > d_page = NULL; > } > -- > 2.4.0 >