From patchwork Fri Dec 23 09:27:02 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 13080770 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id CECC0C3DA6E for ; Fri, 23 Dec 2022 09:27:20 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id BEC14900002; Fri, 23 Dec 2022 04:27:19 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id B9BFF940007; Fri, 23 Dec 2022 04:27:19 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id A63BC900002; Fri, 23 Dec 2022 04:27:19 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id 86812940007 for ; Fri, 23 Dec 2022 04:27:19 -0500 (EST) Received: from smtpin07.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id 5614D80F74 for ; Fri, 23 Dec 2022 09:27:19 +0000 (UTC) X-FDA: 80273042598.07.BA20601 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) by imf28.hostedemail.com (Postfix) with ESMTP id D7C6AC0007 for ; Fri, 23 Dec 2022 09:27:16 +0000 (UTC) Authentication-Results: imf28.hostedemail.com; dkim=pass header.d=infradead.org header.s=bombadil.20210309 header.b=ha7RjNVe; dmarc=none; spf=none (imf28.hostedemail.com: domain of BATV+a36cbb7ae26730e9169d+7061+infradead.org+hch@bombadil.srs.infradead.org has no SPF policy when checking 198.137.202.133) smtp.mailfrom=BATV+a36cbb7ae26730e9169d+7061+infradead.org+hch@bombadil.srs.infradead.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1671787637; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=bsLsQ8oRMe9VK1Dry6x0Z4+LOSid6dNOzo+yQXaFItk=; b=brux5FG97NuHAZ994KmiUepD2EzkgJK6QX1uKHNhZegJEaCzDLYfVhpcmDw4A39u7WvBrZ aQN/vqRteHQWzDMPyz1VABv7oOZSmHQ+B+OB55GdHX112KlPfvgrzyVsDoxK9y+KuwSf+4 oOi5R00KcMEouxv8wcd9j5Xlp/3ssTw= ARC-Authentication-Results: i=1; imf28.hostedemail.com; dkim=pass header.d=infradead.org header.s=bombadil.20210309 header.b=ha7RjNVe; dmarc=none; spf=none (imf28.hostedemail.com: domain of BATV+a36cbb7ae26730e9169d+7061+infradead.org+hch@bombadil.srs.infradead.org has no SPF policy when checking 198.137.202.133) smtp.mailfrom=BATV+a36cbb7ae26730e9169d+7061+infradead.org+hch@bombadil.srs.infradead.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1671787637; a=rsa-sha256; cv=none; b=zZXCqi5iNi7MqoAji24QR0MEbS2S67D1veMiQpatUBsHwWuwdNfdqxW3e9rhx8XoApPfvj JQJqKAYGRMS1T9u+h2jRXu0dEnWmkx0ZphAwvFHwP+ftkMsOtUrQstxH+HDFQFN7CyRYiz mJAWZz/ymWWkajbUb5GdtjP8BCybZn8= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender :Reply-To:Content-Type:Content-ID:Content-Description; bh=bsLsQ8oRMe9VK1Dry6x0Z4+LOSid6dNOzo+yQXaFItk=; b=ha7RjNVen/T0MpbA1+zAHQrVM9 TcOw6Jvc4pcCbgvO1/8lOxnIomOqMaRlR4a8wR+ZcYtehEK3uCFGtxYfcdlY3XLtN9I9qIeifuz+r cxSnqPzC+yBXi7Y4C/3o8ZLVvB3ycAfTQftPjP48RIP/tzUI1djqlGf7SJ/sBV5gwJolcvWrOp4yr u8xnaYh+LWW+SfSYbyzuDkUB1qgsA97kfsC61X6fJ7/FDOzE2Caov2TwMtdE5tzhj+mhjIviwpuPs 6/c3j8S/6Eg0C7vf9oUnnQqeNxmWVO88Lfo78K2cInJf+crbu9Uz0CVK1+fS3XPgR7RcVdLCljc3i WIyjqJXQ==; Received: from [2001:4bb8:199:7829:8d88:c8b3:6416:2f03] (helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1p8eKb-005hRT-Hi; Fri, 23 Dec 2022 09:27:10 +0000 From: Christoph Hellwig To: Andy Gross , Bjorn Andersson , Konrad Dybcio , Mathieu Poirier , Andrew Morton , Uladzislau Rezki Cc: linux-arm-msm@vger.kernel.org, linux-remoteproc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, iommu@lists.linux.dev Subject: [PATCH 1/2] Revert "remoteproc: qcom_q6v5_mss: map/unmap metadata region before/after use" Date: Fri, 23 Dec 2022 10:27:02 +0100 Message-Id: <20221223092703.61927-2-hch@lst.de> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20221223092703.61927-1-hch@lst.de> References: <20221223092703.61927-1-hch@lst.de> MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. 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This commit manages to do three API violations at once: - dereference the return value of dma_alloc_attrs with the DMA_ATTR_NO_KERNEL_MAPPING mapping, which is clearly forbidden and will do the wrong thing on various dma mapping implementations. The fact that dma-direct uses a struct page as a cookie is an undocumented implementation detail - include dma-map-ops.h and use pgprot_dmacoherent despite a clear comment documenting that this is not acceptable - use of the VM_DMA_COHERENT for something that is not the dma-mapping code - use of VM_FLUSH_RESET_PERMS for vmap, while it is only supported for vmalloc Signed-off-by: Christoph Hellwig Acked-by: Manivannan Sadhasivam --- drivers/remoteproc/qcom_q6v5_mss.c | 38 +++++------------------------- 1 file changed, 6 insertions(+), 32 deletions(-) diff --git a/drivers/remoteproc/qcom_q6v5_mss.c b/drivers/remoteproc/qcom_q6v5_mss.c index fddb63cffee078..a8b141db4de63f 100644 --- a/drivers/remoteproc/qcom_q6v5_mss.c +++ b/drivers/remoteproc/qcom_q6v5_mss.c @@ -10,7 +10,6 @@ #include #include #include -#include #include #include #include @@ -933,52 +932,27 @@ static void q6v5proc_halt_axi_port(struct q6v5 *qproc, static int q6v5_mpss_init_image(struct q6v5 *qproc, const struct firmware *fw, const char *fw_name) { - unsigned long dma_attrs = DMA_ATTR_FORCE_CONTIGUOUS | DMA_ATTR_NO_KERNEL_MAPPING; - unsigned long flags = VM_DMA_COHERENT | VM_FLUSH_RESET_PERMS; - struct page **pages; - struct page *page; + unsigned long dma_attrs = DMA_ATTR_FORCE_CONTIGUOUS; dma_addr_t phys; void *metadata; int mdata_perm; int xferop_ret; size_t size; - void *vaddr; - int count; + void *ptr; int ret; - int i; metadata = qcom_mdt_read_metadata(fw, &size, fw_name, qproc->dev); if (IS_ERR(metadata)) return PTR_ERR(metadata); - page = dma_alloc_attrs(qproc->dev, size, &phys, GFP_KERNEL, dma_attrs); - if (!page) { + ptr = dma_alloc_attrs(qproc->dev, size, &phys, GFP_KERNEL, dma_attrs); + if (!ptr) { kfree(metadata); dev_err(qproc->dev, "failed to allocate mdt buffer\n"); return -ENOMEM; } - count = PAGE_ALIGN(size) >> PAGE_SHIFT; - pages = kmalloc_array(count, sizeof(struct page *), GFP_KERNEL); - if (!pages) { - ret = -ENOMEM; - goto free_dma_attrs; - } - - for (i = 0; i < count; i++) - pages[i] = nth_page(page, i); - - vaddr = vmap(pages, count, flags, pgprot_dmacoherent(PAGE_KERNEL)); - kfree(pages); - if (!vaddr) { - dev_err(qproc->dev, "unable to map memory region: %pa+%zx\n", &phys, size); - ret = -EBUSY; - goto free_dma_attrs; - } - - memcpy(vaddr, metadata, size); - - vunmap(vaddr); + memcpy(ptr, metadata, size); /* Hypervisor mapping to access metadata by modem */ mdata_perm = BIT(QCOM_SCM_VMID_HLOS); @@ -1008,7 +982,7 @@ static int q6v5_mpss_init_image(struct q6v5 *qproc, const struct firmware *fw, "mdt buffer not reclaimed system may become unstable\n"); free_dma_attrs: - dma_free_attrs(qproc->dev, size, page, phys, dma_attrs); + dma_free_attrs(qproc->dev, size, ptr, phys, dma_attrs); kfree(metadata); return ret < 0 ? ret : 0; From patchwork Fri Dec 23 09:27:03 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 13080771 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5F723C3DA7A for ; Fri, 23 Dec 2022 09:27:22 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 2C6DE940008; Fri, 23 Dec 2022 04:27:21 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 29CF5940007; Fri, 23 Dec 2022 04:27:21 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 1157F940008; Fri, 23 Dec 2022 04:27:21 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id F0720940007 for ; Fri, 23 Dec 2022 04:27:20 -0500 (EST) Received: from smtpin28.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay03.hostedemail.com (Postfix) with ESMTP id C75F4A0F63 for ; Fri, 23 Dec 2022 09:27:20 +0000 (UTC) X-FDA: 80273042640.28.521B62D Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) by imf10.hostedemail.com (Postfix) with ESMTP id 60146C0008 for ; Fri, 23 Dec 2022 09:27:19 +0000 (UTC) Authentication-Results: imf10.hostedemail.com; dkim=pass header.d=infradead.org header.s=bombadil.20210309 header.b=nIi94Z7x; dmarc=none; spf=none (imf10.hostedemail.com: domain of BATV+a36cbb7ae26730e9169d+7061+infradead.org+hch@bombadil.srs.infradead.org has no SPF policy when checking 198.137.202.133) smtp.mailfrom=BATV+a36cbb7ae26730e9169d+7061+infradead.org+hch@bombadil.srs.infradead.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1671787639; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=uj5J1LKb/4UIpagExHs49WqhLRVbYSUrTZ0b+D0WTrE=; b=U1t6OEFunvbiopk965wf3OZBAqTAEcqs70N98LqNUEV7b2OyCAC7CEUL490SkgOTNvKVqo voiCP+oMFbCjt0NQ1GnHdxcBV9a1QZo8rDoN/PN9tU4UIDoUPvM4rON4LcbNKHQyfP6kqm hndYDj4sI2uJOUbaRK3KlBe7lQycA2k= ARC-Authentication-Results: i=1; imf10.hostedemail.com; dkim=pass header.d=infradead.org header.s=bombadil.20210309 header.b=nIi94Z7x; dmarc=none; spf=none (imf10.hostedemail.com: domain of BATV+a36cbb7ae26730e9169d+7061+infradead.org+hch@bombadil.srs.infradead.org has no SPF policy when checking 198.137.202.133) smtp.mailfrom=BATV+a36cbb7ae26730e9169d+7061+infradead.org+hch@bombadil.srs.infradead.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1671787639; a=rsa-sha256; cv=none; b=snoW0/CQlhbn1XX6j7k5GdJ1268izh1aDI3oNdqaqlex/WGSoZx7weg600sSLGFQgrc/Rn WXubxqD0DvblpbYLpvST0Z+uNrEe4YBNJTwlJD4ttvKHm/kW+1p+sFt1eLPa3LmRSb97R1 uVjfuoSxohIwBAHvcPxYPrYCwQ2xR+A= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender :Reply-To:Content-Type:Content-ID:Content-Description; bh=uj5J1LKb/4UIpagExHs49WqhLRVbYSUrTZ0b+D0WTrE=; b=nIi94Z7xg6PPdFGLsL4tc1cRkg fk8vpDY3Qb3un4xD1x2lRvrSE26lm0N2VFu2vOaxEEGO0wHPAN1Yxwhvxql+tye9eIB5BRKK8X8XV qanYlBggDmH2iPfyygKTQw+sRmJFClDwKQ2kuS5u26BxfEccIXUncjf++Bd5jYUx+wbGGQKfYdk4c 7/mdYbO9Mwpwbfp/CjA+1UI4MNSaFjOBU4i6+PdCtDeRCOcmkq8GcN830iPnmFv/pc+vl/vmUZblo TDK7c8vj1Clg2JWlevxJIVFeIehSHNSv5VExgK9skZq/Qyl4aoiTv6ZetYah0ZlvZ0ESd3tYFwVPO Judum79A==; Received: from [2001:4bb8:199:7829:8d88:c8b3:6416:2f03] (helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1p8eKe-005hTn-Jv; Fri, 23 Dec 2022 09:27:13 +0000 From: Christoph Hellwig To: Andy Gross , Bjorn Andersson , Konrad Dybcio , Mathieu Poirier , Andrew Morton , Uladzislau Rezki Cc: linux-arm-msm@vger.kernel.org, linux-remoteproc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, iommu@lists.linux.dev Subject: [PATCH 2/2] vmalloc: reject vmap with VM_FLUSH_RESET_PERMS Date: Fri, 23 Dec 2022 10:27:03 +0100 Message-Id: <20221223092703.61927-3-hch@lst.de> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20221223092703.61927-1-hch@lst.de> References: <20221223092703.61927-1-hch@lst.de> MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. 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Signed-off-by: Christoph Hellwig --- mm/vmalloc.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/mm/vmalloc.c b/mm/vmalloc.c index 9e30f0b3920325..88a644cde9fb12 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -2849,6 +2849,9 @@ void *vmap(struct page **pages, unsigned int count, might_sleep(); + if (WARN_ON_ONCE(flags & VM_FLUSH_RESET_PERMS)) + return NULL; + /* * Your top guard is someone else's bottom guard. Not having a top * guard compromises someone else's mappings too.