From patchwork Wed Nov 8 02:26:07 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Danilo Krummrich X-Patchwork-Id: 13449526 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 gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 5E539C4332F for ; Wed, 8 Nov 2023 02:27:28 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 9E79110E6F5; Wed, 8 Nov 2023 02:27:26 +0000 (UTC) Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by gabe.freedesktop.org (Postfix) with ESMTPS id BD30C10E365 for ; Wed, 8 Nov 2023 02:27:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1699410442; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=B3DL0Vft98Gq2vq6RutJxBknUxdBNOODfG1hAxtLDfY=; b=hX6oOIyIsFmH6kbrVmw0W/8BnywMc8EYmX5bqxwhYCWuYUBRx16KPPoZyx026vbq1ztJAa i2uhClM6UOYAkDOJju/eTEVPLQ5NHnxG6Wd0PIGeAzixW0Mh+Yp+YGgIyAw7PQ4DzoF/Ia rti+LlIHCDi1Q+GvjqkyQK4RnbSXn00= Received: from mail-ed1-f70.google.com (mail-ed1-f70.google.com [209.85.208.70]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-669-gcpFvI5dNLKtHtaXeOeJLA-1; Tue, 07 Nov 2023 21:27:21 -0500 X-MC-Unique: gcpFvI5dNLKtHtaXeOeJLA-1 Received: by mail-ed1-f70.google.com with SMTP id 4fb4d7f45d1cf-53df4385dccso5053578a12.0 for ; Tue, 07 Nov 2023 18:27:21 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1699410440; x=1700015240; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=B3DL0Vft98Gq2vq6RutJxBknUxdBNOODfG1hAxtLDfY=; b=nwxewtKx3cYuc+M2fKHUFJ5LiRpoSQcTKjJZ1kCaz4QPlQUpuyMZRbOZF1N+3MumdG wMOQQ55jbuRf0sL2kTBH2ECw6eQ5xuAFEBhRWbv7ftruIPvX5F184WILizafQyyEhWmL JE1vU2Wm7z/nxbSZoU1j00tS+OpaY93RYNheIo+HWwdBWg5IgeqoBVK/wYSZFDRT8XWY uAZVf7qZbIQs6jlxN3wMjIedDrzPSryleD6Tf63RGHKjMeBFMAwU7yoH4t4dnCsnTLSG ruIT1GKgJAEJNJOmoJXPRTDOBHDJCgXWIQozB3SGGG6E+JYso6IPJ9ZpEKS3eeOq8YnK jyLA== X-Gm-Message-State: AOJu0YwsTV4deKHLS4UgHYS19/bEBAqZ4grZ5gUUbIFDmdTbs7knTxN/ qb9lrCoO0QSBMCd/wahG7GhcZ9HC9d2QD4JcoQckI0oZ8dyfTWKDX4e5sbQMyoqMeLhxbErggO4 Am5WJH/704hjtYq16qbGH5+uBnl1D X-Received: by 2002:a50:d555:0:b0:540:b0ec:bcd5 with SMTP id f21-20020a50d555000000b00540b0ecbcd5mr357604edj.15.1699410440222; Tue, 07 Nov 2023 18:27:20 -0800 (PST) X-Google-Smtp-Source: AGHT+IG9Cp1VyYPjw3gjL38WhjvNs3AyxxiTpwYPuWjALttn8dwms8ZMyFDJwb9VJPRjdtsqUpNKCw== X-Received: by 2002:a50:d555:0:b0:540:b0ec:bcd5 with SMTP id f21-20020a50d555000000b00540b0ecbcd5mr357590edj.15.1699410439971; Tue, 07 Nov 2023 18:27:19 -0800 (PST) Received: from cassiopeiae.. ([2a02:810d:4b3f:de9c:642:1aff:fe31:a19f]) by smtp.gmail.com with ESMTPSA id m6-20020a50ef06000000b00543525d9fddsm5922217eds.21.2023.11.07.18.27.18 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 07 Nov 2023 18:27:19 -0800 (PST) From: Danilo Krummrich To: airlied@gmail.com, daniel@ffwll.ch, christian.koenig@amd.com, luben.tuikov@amd.com Subject: [PATCH] drm/sched: fix potential page fault in drm_sched_job_init() Date: Wed, 8 Nov 2023 03:26:07 +0100 Message-ID: <20231108022716.15250-1-dakr@redhat.com> X-Mailer: git-send-email 2.41.0 MIME-Version: 1.0 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Danilo Krummrich , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Commit 56e449603f0a ("drm/sched: Convert the GPU scheduler to variable number of run-queues") introduces drm_err() in drm_sched_job_init(), in order to indicate that the given entity has no runq, however at this time job->sched is not yet set, likely to be NULL initialized, and hence shouldn't be used. Replace the corresponding drm_err() call with pr_err() to avoid a potential page fault. While at it, extend the documentation of drm_sched_job_init() to indicate that job->sched is not a valid pointer until drm_sched_job_arm() has been called. Fixes: 56e449603f0a ("drm/sched: Convert the GPU scheduler to variable number of run-queues") Signed-off-by: Danilo Krummrich --- drivers/gpu/drm/scheduler/sched_main.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) base-commit: c015fb6d01adb616fb54824feb55ce5ab18e8ca1 diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c index 27843e37d9b7..dd28389f0ddd 100644 --- a/drivers/gpu/drm/scheduler/sched_main.c +++ b/drivers/gpu/drm/scheduler/sched_main.c @@ -680,6 +680,9 @@ EXPORT_SYMBOL(drm_sched_resubmit_jobs); * This function returns -ENOENT in this case (which probably should be -EIO as * a more meanigful return value). * + * Note that job->sched is not a valid pointer until drm_sched_job_arm() has + * been called. + * * Returns 0 for success, negative error code otherwise. */ int drm_sched_job_init(struct drm_sched_job *job, @@ -691,7 +694,7 @@ int drm_sched_job_init(struct drm_sched_job *job, * or worse--a blank screen--leave a trail in the * logs, so this can be debugged easier. */ - drm_err(job->sched, "%s: entity has no rq!\n", __func__); + pr_err("%s: entity has no rq!\n", __func__); return -ENOENT; }