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 1BAF31BC20; Fri, 12 Jul 2024 23:33:08 +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=1720827189; cv=none; b=RUquNfdjpxv59r//pyRuG35ye04+TFtHc6blxY0/xLtCH64YO4T2oP3ciShIbQkufYr/o/R43hQ4rcJN3/SeBymeu+tJBO6wQg0+1F4Qm5Eo18MxuoPzIXa25QKW6cbJj35SazeDI+ekNsD3AF4aGssGm87hH593ByHg526gMIg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720827189; c=relaxed/simple; bh=wf9SUj8vXNTkTRRQtPM01POqFTV0CMIZQ+/FPslmrqg=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=KtmyG12Iz2ZxG1+lcC7qYT8TLsz3jql5v1YEEjLIBRfDE4XExst5LJbsE4fsnZnLB1R8KsKZF/l2HD144h/czH32VZwkof5WbgNAMD5Mc8PS9TBgjXDSnh/6hEEgsoJiGNwVHDgTxKt2GL4gJVcWVh4rchdj9TGLFQMRGlfflig= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id CC0BFC32782; Fri, 12 Jul 2024 23:33:07 +0000 (UTC) Date: Fri, 12 Jul 2024 19:33:06 -0400 From: Steven Rostedt To: Nikita Kiryushin Cc: Masami Hiramatsu , Mathieu Desnoyers , linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, lvc-project@linuxtesting.org Subject: Re: [PATCH] tracing: remove unreachable trace_array_put Message-ID: <20240712193306.3174c85e@gandalf.local.home> In-Reply-To: <20240712201258.99070-1-kiryushin@ancud.ru> References: <20240712201258.99070-1-kiryushin@ancud.ru> X-Mailer: Claws Mail 3.20.0git84 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Fri, 12 Jul 2024 23:12:58 +0300 Nikita Kiryushin wrote: > There is a trace_array_put() in check result for > nonseekable_open() in tracing_buffers_open(). However, > it would be never executed as nonseekable_open never fails > (by design). > > Remove the check and associated unreachable code. Then why does it return a value? If someday it can return a failure, this would then cause a leak. It doesn't hurt to leave it in. So NACK. -- Steve > > Found by Linux Verification Center (linuxtesting.org) with SVACE. > > Fixes: 7b85af630348 ("tracing: Get trace_array ref counts when accessing trace files") > Signed-off-by: Nikita Kiryushin > --- > kernel/trace/trace.c | 6 +----- > 1 file changed, 1 insertion(+), 5 deletions(-) > > diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c > index 578a49ff5c32..7e480501b509 100644 > --- a/kernel/trace/trace.c > +++ b/kernel/trace/trace.c > @@ -7883,11 +7883,7 @@ static int tracing_buffers_open(struct inode *inode, struct file *filp) > > mutex_unlock(&trace_types_lock); > > - ret = nonseekable_open(inode, filp); > - if (ret < 0) > - trace_array_put(tr); > - > - return ret; > + return nonseekable_open(inode, filp); > } > > static __poll_t