From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mout-p-101.mailbox.org (mout-p-101.mailbox.org [80.241.56.151]) (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 48B8E3A1C9 for ; Tue, 25 Aug 2026 07:14:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=80.241.56.151 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787642080; cv=none; b=qbQzqrhulAu1eUanC+aZTvp2ee4CWAWiraKxqYH36yosO7fXabpA/qLfXFnBoL6Md3gkqqCBgA0Y5mnnCDtlRN6An6j5NenxXrWF0WpXYnr365Srtm6tDMjvpgQya4e9oc/Uw4TfwRgv3jHvz2ll2P/e0Y5mSgi3NuWQCY/1i1o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787642080; c=relaxed/simple; bh=dGv2KWfBDQc+FeSmUeOh9vtD6HYV/eBbEd1lhqbS16s=; h=Message-ID:Subject:From:To:Cc:Date:In-Reply-To:References: Content-Type:MIME-Version; b=AnUNO4jPsY5UpsbU+mkiiyYa2Hx8YqBuAfD73613O/0ROkzj8bUFo7BOrYbdRAYDDhLTZNU2s++zWa8YS9j0jUAtb9hOwOl5l7arEAq9lUlJLpTnanwMBDFq3ha2iA/POQwt3fGpyzXWipSz84Y0hJ8OqKIRwLemiX4sCljm8rM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=mailbox.org; spf=pass smtp.mailfrom=mailbox.org; dkim=pass (2048-bit key) header.d=mailbox.org header.i=@mailbox.org header.b=WRDKP7Ep; arc=none smtp.client-ip=80.241.56.151 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=mailbox.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=mailbox.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=mailbox.org header.i=@mailbox.org header.b="WRDKP7Ep" Received: from smtp2.mailbox.org (smtp2.mailbox.org [10.196.197.2]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange x25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mout-p-101.mailbox.org (Postfix) with ESMTPS id 4hTfD26D2lz8sp8; Tue, 25 Aug 2026 09:14:26 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mailbox.org; s=mail20150812; t=1787642066; h=from:from:reply-to: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: in-reply-to:in-reply-to:references:references; bh=SIJZZD/XaPkQPLVFhESspAkltHs+LixM6ANfzdKnl8Q=; b=WRDKP7EpQORH1V1XZv2cV2vKkh6v2tJ1HENpxAJ3tkKlHIGCT3E8oOztlKSuB90W7756MT 0QQGfGSctWCIf1RIsr/WP7H6D09ro/LO/uNuoFkEZm5CQwWjWN4hrFs1FepUEPlAK9QZMV LfIdLKn6voz17KTQMK0BIRs9YDQiPnTsRBCeCN5VXWQwjvgfM3NnRGUbPP5/TGLER+1eFU mYjqpQ9yq/uVr68mSWJJCHKycVsP0RYH/M7sCX9obtwaqHs0ihJZYuabApFW2FNLZ9iVfY QzanWa3WOkSXo+lYlwAjpF+BMQVEvAL84KVUiRdHLkqkQpSziItdGt3VVGdgAg== Message-ID: <13be98c209664e14d6dda700775c4d6c6366bb92.camel@mailbox.org> Subject: Re: [PATCH] drm/sched: Guard against NULL dev in drm_sched_job trace event From: Philipp Stanner Reply-To: phasta@kernel.org To: oushixiong1025@163.com, Matthew Brost Cc: Danilo Krummrich , Philipp Stanner , Christian =?ISO-8859-1?Q?K=F6nig?= , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Shixiong Ou Date: Tue, 25 Aug 2026 09:14:20 +0200 In-Reply-To: <20260821084748.543645-1-oushixiong1025@163.com> References: <20260821084748.543645-1-oushixiong1025@163.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MBO-RS-ID: f8a830b610e67b2e361 X-MBO-RS-META: agp4y6hfurxmuymkj81c9z9cpmkszcez On Fri, 2026-08-21 at 16:47 +0800, oushixiong1025@163.com wrote: > From: Shixiong Ou >=20 > The drm_sched_job trace event class calls dev_name() on > sched_job->sched->dev without checking for NULL. Since the > dev field in drm_sched_init_args is optional (used for > debugging), a NULL dev causes a kernel oops when the trace > event fires. >=20 > The DRM scheduler KUnit tests do not set the dev field in > drm_sched_init_args, leaving sched->dev as NULL. This causes > a NULL pointer dereference when the drm_sched_job trace event > fires during test execution, as dev_name(NULL) is called. >=20 > =C2=A0 Unable to handle kernel NULL pointer dereference at virtual addres= s 0000000000000050 > =C2=A0 Call trace: > =C2=A0=C2=A0 trace_event_raw_event_drm_sched_job+0x90/0x258 > =C2=A0=C2=A0 __traceiter_drm_sched_job_queue+0x4c/0x78 > =C2=A0=C2=A0 drm_sched_entity_push_job+0x188/0x380 > =C2=A0=C2=A0 drm_sched_basic_entity_cleanup+0xfc/0x240 > =C2=A0=C2=A0 kunit_try_run_case+0x74/0x170 Yes, that looks correct, thx for fixing. Can you send a v2 with your commit message's line length set to 72 characters? Only the title line should be aimed to be 50 chars wide. Regards, P. >=20 > Signed-off-by: Shixiong Ou > --- > =C2=A0drivers/gpu/drm/scheduler/gpu_scheduler_trace.h | 3 ++- > =C2=A01 file changed, 2 insertions(+), 1 deletion(-) >=20 > diff --git a/drivers/gpu/drm/scheduler/gpu_scheduler_trace.h b/drivers/gp= u/drm/scheduler/gpu_scheduler_trace.h > index 261713dd7d5a..319a3ec54bec 100644 > --- a/drivers/gpu/drm/scheduler/gpu_scheduler_trace.h > +++ b/drivers/gpu/drm/scheduler/gpu_scheduler_trace.h > @@ -61,7 +61,8 @@ DECLARE_EVENT_CLASS(drm_sched_job, > =C2=A0 =C2=A0=C2=A0=C2=A0=C2=A0 __string(name, sched_job->sched->name) > =C2=A0 =C2=A0=C2=A0=C2=A0=C2=A0 __field(u32, job_count) > =C2=A0 =C2=A0=C2=A0=C2=A0=C2=A0 __field(int, hw_job_count) > - =C2=A0=C2=A0=C2=A0=C2=A0 __string(dev, dev_name(sched_job->sched->dev= )) > + =C2=A0=C2=A0=C2=A0=C2=A0 __string(dev, sched_job->sched->dev ? > + =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 dev_name(sched_job->sched->dev) : "no= ne") > =C2=A0 =C2=A0=C2=A0=C2=A0=C2=A0 __field(u64, fence_context) > =C2=A0 =C2=A0=C2=A0=C2=A0=C2=A0 __field(u64, fence_seqno) > =C2=A0 =C2=A0=C2=A0=C2=A0=C2=A0 __field(u64, client_id)