From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C15A3C43142 for ; Tue, 26 Jun 2018 14:31:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6595B26C6F for ; Tue, 26 Jun 2018 14:31:55 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6595B26C6F Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=daenzer.net Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S936120AbeFZObx (ORCPT ); Tue, 26 Jun 2018 10:31:53 -0400 Received: from mail.netline.ch ([148.251.143.178]:52561 "EHLO netline-mail3.netline.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935535AbeFZObw (ORCPT ); Tue, 26 Jun 2018 10:31:52 -0400 Received: from localhost (localhost [127.0.0.1]) by netline-mail3.netline.ch (Postfix) with ESMTP id B9E2D2A604F; Tue, 26 Jun 2018 16:31:49 +0200 (CEST) X-Virus-Scanned: Debian amavisd-new at netline-mail3.netline.ch Received: from netline-mail3.netline.ch ([127.0.0.1]) by localhost (netline-mail3.netline.ch [127.0.0.1]) (amavisd-new, port 10024) with LMTP id 8_XT_7TIJPtH; Tue, 26 Jun 2018 16:31:49 +0200 (CEST) Received: from kaveri (252.228.127.176.dynamic.wline.res.cust.swisscom.ch [176.127.228.252]) by netline-mail3.netline.ch (Postfix) with ESMTPSA id 5E4B02A604C; Tue, 26 Jun 2018 16:31:48 +0200 (CEST) Received: from daenzer by kaveri with local (Exim 4.91) (envelope-from ) id 1fXp0V-0003jL-Gd; Tue, 26 Jun 2018 16:31:47 +0200 From: =?UTF-8?q?Michel=20D=C3=A4nzer?= To: Sumit Semwal Cc: linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org, linux-kernel@vger.kernel.org, amd-gfx@lists.freedesktop.org Subject: [PATCH] dma-buf: Move BUG_ON from _add_shared_fence to _add_shared_inplace Date: Tue, 26 Jun 2018 16:31:47 +0200 Message-Id: <20180626143147.14296-1-michel@daenzer.net> X-Mailer: git-send-email 2.18.0 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Michel Dänzer Fixes the BUG_ON spuriously triggering under the following circumstances: * ttm_eu_reserve_buffers processes a list containing multiple BOs using the same reservation object, so it calls reservation_object_reserve_shared with that reservation object once for each such BO. * In reservation_object_reserve_shared, old->shared_count == old->shared_max - 1, so obj->staged is freed in preparation of an in-place update. * ttm_eu_fence_buffer_objects calls reservation_object_add_shared_fence once for each of the BOs above, always with the same fence. * The first call adds the fence in the remaining free slot, after which old->shared_count == old->shared_max. In the next call to reservation_object_add_shared_fence, the BUG_ON triggers. However, nothing bad would happen in reservation_object_add_shared_inplace, since the fence is already in the reservation object. Prevent this by moving the BUG_ON to where an overflow would actually happen (e.g. if a buggy caller didn't call reservation_object_reserve_shared before). Cc: stable@vger.kernel.org Signed-off-by: Michel Dänzer --- drivers/dma-buf/reservation.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/dma-buf/reservation.c b/drivers/dma-buf/reservation.c index 314eb1071cce..532545b9488e 100644 --- a/drivers/dma-buf/reservation.c +++ b/drivers/dma-buf/reservation.c @@ -141,6 +141,7 @@ reservation_object_add_shared_inplace(struct reservation_object *obj, if (signaled) { RCU_INIT_POINTER(fobj->shared[signaled_idx], fence); } else { + BUG_ON(fobj->shared_count >= fobj->shared_max); RCU_INIT_POINTER(fobj->shared[fobj->shared_count], fence); fobj->shared_count++; } @@ -230,10 +231,9 @@ void reservation_object_add_shared_fence(struct reservation_object *obj, old = reservation_object_get_list(obj); obj->staged = NULL; - if (!fobj) { - BUG_ON(old->shared_count >= old->shared_max); + if (!fobj) reservation_object_add_shared_inplace(obj, old, fence); - } else + else reservation_object_add_shared_replace(obj, old, fobj, fence); } EXPORT_SYMBOL(reservation_object_add_shared_fence); -- 2.18.0 From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?UTF-8?q?Michel=20D=C3=A4nzer?= Subject: [PATCH] dma-buf: Move BUG_ON from _add_shared_fence to _add_shared_inplace Date: Tue, 26 Jun 2018 16:31:47 +0200 Message-ID: <20180626143147.14296-1-michel@daenzer.net> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: amd-gfx-bounces-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org Sender: "amd-gfx" To: Sumit Semwal Cc: linaro-mm-sig-cunTk1MwBs8s++Sfvej+rw@public.gmane.org, amd-gfx-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, dri-devel-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org, linux-media-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: dri-devel@lists.freedesktop.org RnJvbTogTWljaGVsIETDpG56ZXIgPG1pY2hlbC5kYWVuemVyQGFtZC5jb20+CgpGaXhlcyB0aGUg QlVHX09OIHNwdXJpb3VzbHkgdHJpZ2dlcmluZyB1bmRlciB0aGUgZm9sbG93aW5nCmNpcmN1bXN0 YW5jZXM6CgoqIHR0bV9ldV9yZXNlcnZlX2J1ZmZlcnMgcHJvY2Vzc2VzIGEgbGlzdCBjb250YWlu aW5nIG11bHRpcGxlIEJPcyB1c2luZwogIHRoZSBzYW1lIHJlc2VydmF0aW9uIG9iamVjdCwgc28g aXQgY2FsbHMKICByZXNlcnZhdGlvbl9vYmplY3RfcmVzZXJ2ZV9zaGFyZWQgd2l0aCB0aGF0IHJl c2VydmF0aW9uIG9iamVjdCBvbmNlCiAgZm9yIGVhY2ggc3VjaCBCTy4KKiBJbiByZXNlcnZhdGlv bl9vYmplY3RfcmVzZXJ2ZV9zaGFyZWQsIG9sZC0+c2hhcmVkX2NvdW50ID09CiAgb2xkLT5zaGFy ZWRfbWF4IC0gMSwgc28gb2JqLT5zdGFnZWQgaXMgZnJlZWQgaW4gcHJlcGFyYXRpb24gb2YgYW4K ICBpbi1wbGFjZSB1cGRhdGUuCiogdHRtX2V1X2ZlbmNlX2J1ZmZlcl9vYmplY3RzIGNhbGxzIHJl c2VydmF0aW9uX29iamVjdF9hZGRfc2hhcmVkX2ZlbmNlCiAgb25jZSBmb3IgZWFjaCBvZiB0aGUg Qk9zIGFib3ZlLCBhbHdheXMgd2l0aCB0aGUgc2FtZSBmZW5jZS4KKiBUaGUgZmlyc3QgY2FsbCBh ZGRzIHRoZSBmZW5jZSBpbiB0aGUgcmVtYWluaW5nIGZyZWUgc2xvdCwgYWZ0ZXIgd2hpY2gKICBv bGQtPnNoYXJlZF9jb3VudCA9PSBvbGQtPnNoYXJlZF9tYXguCgpJbiB0aGUgbmV4dCBjYWxsIHRv IHJlc2VydmF0aW9uX29iamVjdF9hZGRfc2hhcmVkX2ZlbmNlLCB0aGUgQlVHX09OCnRyaWdnZXJz LiBIb3dldmVyLCBub3RoaW5nIGJhZCB3b3VsZCBoYXBwZW4gaW4KcmVzZXJ2YXRpb25fb2JqZWN0 X2FkZF9zaGFyZWRfaW5wbGFjZSwgc2luY2UgdGhlIGZlbmNlIGlzIGFscmVhZHkgaW4gdGhlCnJl c2VydmF0aW9uIG9iamVjdC4KClByZXZlbnQgdGhpcyBieSBtb3ZpbmcgdGhlIEJVR19PTiB0byB3 aGVyZSBhbiBvdmVyZmxvdyB3b3VsZCBhY3R1YWxseQpoYXBwZW4gKGUuZy4gaWYgYSBidWdneSBj YWxsZXIgZGlkbid0IGNhbGwKcmVzZXJ2YXRpb25fb2JqZWN0X3Jlc2VydmVfc2hhcmVkIGJlZm9y ZSkuCgpDYzogc3RhYmxlQHZnZXIua2VybmVsLm9yZwpTaWduZWQtb2ZmLWJ5OiBNaWNoZWwgRMOk bnplciA8bWljaGVsLmRhZW56ZXJAYW1kLmNvbT4KLS0tCiBkcml2ZXJzL2RtYS1idWYvcmVzZXJ2 YXRpb24uYyB8IDYgKysrLS0tCiAxIGZpbGUgY2hhbmdlZCwgMyBpbnNlcnRpb25zKCspLCAzIGRl bGV0aW9ucygtKQoKZGlmZiAtLWdpdCBhL2RyaXZlcnMvZG1hLWJ1Zi9yZXNlcnZhdGlvbi5jIGIv ZHJpdmVycy9kbWEtYnVmL3Jlc2VydmF0aW9uLmMKaW5kZXggMzE0ZWIxMDcxY2NlLi41MzI1NDVi OTQ4OGUgMTAwNjQ0Ci0tLSBhL2RyaXZlcnMvZG1hLWJ1Zi9yZXNlcnZhdGlvbi5jCisrKyBiL2Ry aXZlcnMvZG1hLWJ1Zi9yZXNlcnZhdGlvbi5jCkBAIC0xNDEsNiArMTQxLDcgQEAgcmVzZXJ2YXRp b25fb2JqZWN0X2FkZF9zaGFyZWRfaW5wbGFjZShzdHJ1Y3QgcmVzZXJ2YXRpb25fb2JqZWN0ICpv YmosCiAJaWYgKHNpZ25hbGVkKSB7CiAJCVJDVV9JTklUX1BPSU5URVIoZm9iai0+c2hhcmVkW3Np Z25hbGVkX2lkeF0sIGZlbmNlKTsKIAl9IGVsc2UgeworCQlCVUdfT04oZm9iai0+c2hhcmVkX2Nv dW50ID49IGZvYmotPnNoYXJlZF9tYXgpOwogCQlSQ1VfSU5JVF9QT0lOVEVSKGZvYmotPnNoYXJl ZFtmb2JqLT5zaGFyZWRfY291bnRdLCBmZW5jZSk7CiAJCWZvYmotPnNoYXJlZF9jb3VudCsrOwog CX0KQEAgLTIzMCwxMCArMjMxLDkgQEAgdm9pZCByZXNlcnZhdGlvbl9vYmplY3RfYWRkX3NoYXJl ZF9mZW5jZShzdHJ1Y3QgcmVzZXJ2YXRpb25fb2JqZWN0ICpvYmosCiAJb2xkID0gcmVzZXJ2YXRp b25fb2JqZWN0X2dldF9saXN0KG9iaik7CiAJb2JqLT5zdGFnZWQgPSBOVUxMOwogCi0JaWYgKCFm b2JqKSB7Ci0JCUJVR19PTihvbGQtPnNoYXJlZF9jb3VudCA+PSBvbGQtPnNoYXJlZF9tYXgpOwor CWlmICghZm9iaikKIAkJcmVzZXJ2YXRpb25fb2JqZWN0X2FkZF9zaGFyZWRfaW5wbGFjZShvYmos IG9sZCwgZmVuY2UpOwotCX0gZWxzZQorCWVsc2UKIAkJcmVzZXJ2YXRpb25fb2JqZWN0X2FkZF9z aGFyZWRfcmVwbGFjZShvYmosIG9sZCwgZm9iaiwgZmVuY2UpOwogfQogRVhQT1JUX1NZTUJPTChy ZXNlcnZhdGlvbl9vYmplY3RfYWRkX3NoYXJlZF9mZW5jZSk7Ci0tIAoyLjE4LjAKCl9fX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fCmFtZC1nZnggbWFpbGluZyBs aXN0CmFtZC1nZnhAbGlzdHMuZnJlZWRlc2t0b3Aub3JnCmh0dHBzOi8vbGlzdHMuZnJlZWRlc2t0 b3Aub3JnL21haWxtYW4vbGlzdGluZm8vYW1kLWdmeAo=