From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 16307606A31C for ; Thu, 29 Oct 2026 06:21:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=HldSW/uG Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 74D5410E784; Thu, 29 Oct 2026 06:21:27 +0000 (UTC) Received: from sea.source.kernel.org (sea.source.kernel.org [172.234.252.31]) by gabe.freedesktop.org (Postfix) with ESMTPS id AC85210E784 for ; Thu, 29 Oct 2026 06:21:20 +0000 (UTC) Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id 5FD3243269; Thu, 29 Oct 2026 06:21:20 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1D2291F01825; Thu, 29 Oct 2026 06:21:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793254880; bh=MwCOmZXP6z+DhMZx3i10QCICGtnTp8Zag+DzzpR+f4A=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=HldSW/uGlUNoMVkJQszV8/IK2iidbN21QOa+CKDvSGExnyoKp5sgbxg+i3gx7r7T4 8aN/u+XbUiv5EeVmtCoDrpfzpRQbdAFd3JXXmMPt6Vmx4GJyZ5r2Ts9pJJGpandtpB E6foerRGdACBrRjVCyr6C3sTU4i3y1Js0fknSOr6Z+qyPMFcCo/UeXOBvyvHadzf6N mIZpb7e1fKB3Ag99yFI0Qh3kfc4Ss/UhgwAgXzy5thLBf2IKoDZVNJhk2WuyjWdrBX vqyxsLH0WFdWo4+bhImWX/bNBILokghowKxZKbbV0AvXPF6m1vw6eRK16aKc7NDPVx bMTzI6f4RTkKA== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH v4 1/4] drm/imagination: Limit access to the MIPS firmware interface To: "Alexandru Dadu" Cc: dri-devel@lists.freedesktop.org In-Reply-To: <20261029-b4-simplify-mips-pte-defs-v4-1-9656041e040b@imgtec.com> References: <20261029-b4-simplify-mips-pte-defs-v4-0-9656041e040b@imgtec.com> <20261029-b4-simplify-mips-pte-defs-v4-1-9656041e040b@imgtec.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Thu, 29 Oct 2026 06:21:19 +0000 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: sashiko-reviews@lists.linux.dev Sender: "dri-devel" X-Spam-Status: No, score=-10.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 X-Archived-By: Thank you for your contribution! Sashiko AI review found 2 potential issue(= s) to consider: - [Medium] drm/imagination: wrong page count check and loop bound in pvr_vm= _get_pt_phys_addrs() - [Low] drm/imagination: mismatched kernel-doc member names in struct pvr_f= w_device -- commit 1c0b6ad7b66c2f99b867a56a6bc1405d6e8aad70 Author: Alessio Belle drm/imagination: Limit access to the MIPS firmware interface This commit splits struct pvr_fw_mips_data into separate structures for the main MIPS firmware logic and the MIPS VM logic, removes pvr_fw_mips.h, and adds pvr_vm_get_pt_phys_addrs() to retrieve the physical addresses of the MIPS firmware page table. > diff --git a/drivers/gpu/drm/imagination/pvr_fw.h b/drivers/gpu/drm/imagi= nation/pvr_fw.h > index 4b25291135b69..0d4507f55c84b 100644 > --- a/drivers/gpu/drm/imagination/pvr_fw.h > +++ b/drivers/gpu/drm/imagination/pvr_fw.h > @@ -310,10 +310,15 @@ struct pvr_fw_device { > /** @funcs: Function table for the FW processor used by this device. */ > const struct pvr_fw_defs *defs; > =20 > - /** @processor_data: Pointer to data specific to FW processor. */ > + /** @processor_data: Data specific to FW processor. */ > union { > - /** @mips_data: Pointer to MIPS-specific data. */ > - struct pvr_fw_mips_data *mips_data; > + /** @mips_data: MIPS-specific data. */ > + struct { > + /** @mips_fw_data: Pointer to MIPS-FW-specific data. */ > + struct pvr_fw_mips_data *fw_data; > + /** @mips_vm_data: Pointer to MIPS-VM-specific data. */ > + struct pvr_vm_mips_data *vm_data; > + } mips_data; [Severity: Low] This isn't a bug, but in struct pvr_fw_device in drivers/gpu/drm/imagination/pvr_fw.h, should the kernel-doc tags @mips_fw_data and @mips_vm_data be @fw_data and @vm_data to match the struct member names? > diff --git a/drivers/gpu/drm/imagination/pvr_vm_mips.c b/drivers/gpu/drm/= imagination/pvr_vm_mips.c > index 5847a1c92bea8..264ea0fccf9c1 100644 > --- a/drivers/gpu/drm/imagination/pvr_vm_mips.c > +++ b/drivers/gpu/drm/imagination/pvr_vm_mips.c > @@ -16,6 +17,31 @@ > #include > #include > =20 > +#define PVR_MIPS_PT_PAGE_COUNT \ > + DIV_ROUND_UP(ROGUE_MIPSFW_MAX_NUM_PAGETABLE_PAGES * ROGUE_MIPSFW_PAGE_S= IZE_4K, PAGE_SIZE) > + > +/** > + * struct pvr_vm_mips_data - MIPS-VM-specific data > + */ > +struct pvr_vm_mips_data { > + /** > + * @pt_pages: Pages containing MIPS pagetable. > + */ > + struct page *pt_pages[PVR_MIPS_PT_PAGE_COUNT]; > + > + /** @pt: Pointer to CPU mapping of MIPS pagetable. */ > + u32 *pt; > + > + /** @pt_dma_addr: DMA mappings of MIPS pagetable. */ > + dma_addr_t pt_dma_addr[PVR_MIPS_PT_PAGE_COUNT]; [ ... ] > @@ -230,8 +256,38 @@ pvr_vm_mips_unmap(struct pvr_device *pvr_dev, struct= pvr_fw_object *fw_obj) > ROGUE_MIPSFW_LOG2_PAGE_SIZE_4K; > =20 > for (u32 pfn =3D start_pfn; pfn < end_pfn; pfn++) > - WRITE_ONCE(mips_data->pt[pfn], 0); > + WRITE_ONCE(vm_data->pt[pfn], 0); > =20 > pvr_mmu_flush_request_all(pvr_dev); > WARN_ON(pvr_mmu_flush_exec(pvr_dev, true)); > } > + > +/** > + * pvr_vm_get_pt_phys_addrs() - Acquire the physical addresses of the MI= PS FW page table pages > + * @pvr_dev: Target PowerVR device. > + * @phys_addrs: Output array for physical addresses of MIPS FW page tabl= e pages. > + * @max_num_addrs: Maximum number of addresses that can be written to @p= hys_addrs. > + * > + * Returns: > + * * 0 on success, or > + * * -%EINVAL if @phys_addrs cannot accommodate all MIPS FW page table = pages. > + */ > +int > +pvr_vm_get_pt_phys_addrs(struct pvr_device *pvr_dev, u64 *phys_addrs, in= t max_num_addrs) > +{ > + struct pvr_fw_device *fw_dev =3D &pvr_dev->fw_dev; > + struct pvr_vm_mips_data *vm_data =3D fw_dev->processor_data.mips_data.v= m_data; > + > + if (ARRAY_SIZE(vm_data->pt_pages) > max_num_addrs) > + return -EINVAL; > + > + for (u32 page_nr =3D 0; page_nr < max_num_addrs; page_nr++) { > + /* Firmware expects 4k pages, but host page size might be different. */ > + u32 src_page_nr =3D (page_nr * ROGUE_MIPSFW_PAGE_SIZE_4K) >> PAGE_SHIF= T; > + u32 page_offset =3D (page_nr * ROGUE_MIPSFW_PAGE_SIZE_4K) & ~PAGE_MASK; > + > + phys_addrs[page_nr] =3D vm_data->pt_dma_addr[src_page_nr] + page_offse= t; > + } > + > + return 0; > +} [Severity: Medium] In pvr_vm_get_pt_phys_addrs() in drivers/gpu/drm/imagination/pvr_vm_mips.c (and its declaration in drivers/gpu/drm/imagination/pvr_vm_mips.h), should the size check and loop bound use ROGUE_MIPSFW_MAX_NUM_PAGETABLE_PAGES instead of ARRAY_SIZE(vm_data->pt_pages) and max_num_addrs, and should max_num_addrs be an unsigned type such as u32? vm_data->pt_pages and vm_data->pt_dma_addr are sized to PVR_MIPS_PT_PAGE_COUNT, which is the number of host PAGE_SIZE pages (for example, 1 on 16K or 64K page hosts), whereas phys_addrs is populated with 4K MIPS firmware page table addresses (ROGUE_MIPSFW_MAX_NUM_PAGETABLE_PAGES =3D 4). Checking ARRAY_SIZE(vm_data->pt_pages) > max_num_addrs validates against the host page count rather than ROGUE_MIPSFW_MAX_NUM_PAGETABLE_PAGES, so on 16K or 64K page hosts a buffer with fewer than 4 entries would pass the check. Additionally, iterating page_nr up to max_num_addrs rather than ROGUE_MIPSFW_MAX_NUM_PAGETABLE_PAGES means that if a caller passes max_num_addrs > ROGUE_MIPSFW_MAX_NUM_PAGETABLE_PAGES, src_page_nr will index past the end of vm_data->pt_dma_addr[]. Because max_num_addrs is a signed i= nt compared against unsigned ARRAY_SIZE() and u32 page_nr, this also triggers -Wsign-compare warnings and allows negative values to bypass the check. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261029-b4-simplif= y-mips-pte-defs-v4-0-9656041e040b@imgtec.com?part=3D1