From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 70D2B3451BF; Tue, 16 Dec 2025 11:57:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765886272; cv=none; b=HtCDJwdYUxXVSc+isRXMoKOY1D2Mawut8n8jsNBt4WlsfmfnB5lCiBVG4YhkDhRCojtC3eTGJR4hFnv3zR7TaWvx1SQxdm9dP+esRVaw86YJsjsn2q4YonA/cSflFzwfe3RRLhytRMMJbn+yBSAyIpe1esN0QZMatv0CaAOpBY0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765886272; c=relaxed/simple; bh=EyRCKv2NApV1PQLD6KgCY4F4cZu0xbRRWn1g6uBc1KM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=iYcL87YBt1niL3FFvGw30zW809zhMrDQcLrlsLFKXZzeX39MwVE9U/uuHAyHdMOuSUxnu5ZH6iBhAHcOFGH/NT5Rn/xz4LeqcAuLHpkGBtRmX00bsk8KS87J9CedREkHdUmReWOYvCZWyiodtJqgtr5+Q2gwmv3W3/+3t6dW7uc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=LEBnaRy8; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="LEBnaRy8" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DE14DC4CEF1; Tue, 16 Dec 2025 11:57:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1765886272; bh=EyRCKv2NApV1PQLD6KgCY4F4cZu0xbRRWn1g6uBc1KM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=LEBnaRy8iZZ9yjhs5aigBn1QkCxrWXaQscgKULUxvKEPs0iP1iZ8ptLehex5ScIwH ICTWd+g4J3uglu3NzMppxCtc5ix3h1LReuofKjDQnU5EIW+smfLHATOMGc/q8+w4Qa nOu8pvNG/Md+Xt7U/I1+lPKbrdvqY3+3MZCsJMtI= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Akash Goel , Boris Brezillon , Steven Price , Sasha Levin Subject: [PATCH 6.17 355/507] drm/panthor: Avoid adding of kernel BOs to extobj list Date: Tue, 16 Dec 2025 12:13:16 +0100 Message-ID: <20251216111358.318068712@linuxfoundation.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20251216111345.522190956@linuxfoundation.org> References: <20251216111345.522190956@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.17-stable review patch. If anyone has any objections, please let me know. ------------------ From: Akash Goel [ Upstream commit ce04ec03a9c2c4f3e60e26f21311b25d5a478208 ] The kernel BOs unnecessarily got added to the external objects list of drm_gpuvm, when mapping to GPU, which would have resulted in few extra CPU cycles being spent at the time of job submission as drm_exec_until_all_locked() loop iterates over all external objects. Kernel BOs are private to a VM and so they share the dma_resv object of the dummy GEM object created for a VM. Use of DRM_EXEC_IGNORE_DUPLICATES flag ensured the recursive locking of the dummy GEM object was ignored. Also no extra space got allocated to add fences to the dma_resv object of dummy GEM object. So no other impact apart from few extra CPU cycles. This commit sets the pointer to dma_resv object of GEM object of kernel BOs before they are mapped to GPU, to prevent them from being added to external objects list. v2: Add R-bs and fixes tags Fixes: 8a1cc07578bf ("drm/panthor: Add GEM logical block") Signed-off-by: Akash Goel Reviewed-by: Boris Brezillon Reviewed-by: Steven Price Link: https://patch.msgid.link/20251120172118.2741724-1-akash.goel@arm.com Signed-off-by: Boris Brezillon Signed-off-by: Sasha Levin --- drivers/gpu/drm/panthor/panthor_gem.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/panthor/panthor_gem.c b/drivers/gpu/drm/panthor/panthor_gem.c index 6830a89a7c10b..aca09bc449fc1 100644 --- a/drivers/gpu/drm/panthor/panthor_gem.c +++ b/drivers/gpu/drm/panthor/panthor_gem.c @@ -145,6 +145,9 @@ panthor_kernel_bo_create(struct panthor_device *ptdev, struct panthor_vm *vm, bo = to_panthor_bo(&obj->base); kbo->obj = &obj->base; bo->flags = bo_flags; + bo->exclusive_vm_root_gem = panthor_vm_root_gem(vm); + drm_gem_object_get(bo->exclusive_vm_root_gem); + bo->base.base.resv = bo->exclusive_vm_root_gem->resv; if (vm == panthor_fw_vm(ptdev)) debug_flags |= PANTHOR_DEBUGFS_GEM_USAGE_FLAG_FW_MAPPED; @@ -168,9 +171,6 @@ panthor_kernel_bo_create(struct panthor_device *ptdev, struct panthor_vm *vm, goto err_free_va; kbo->vm = panthor_vm_get(vm); - bo->exclusive_vm_root_gem = panthor_vm_root_gem(vm); - drm_gem_object_get(bo->exclusive_vm_root_gem); - bo->base.base.resv = bo->exclusive_vm_root_gem->resv; return kbo; err_free_va: -- 2.51.0