From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) (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 8FBFC25486D; Wed, 8 Oct 2025 15:47:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=216.40.44.13 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759938474; cv=none; b=OonYmOZicDkzoTa5H3DlusSlZ5pyrq1Mm8G3X4IJKKTkjysSsaeZU7mT4AEypQjmjneTZRgh6pH/QcEtjZ2BqG5KXg7f1R/W8LmEOxcOnbmq1F/vC8qbZwcEitZ9UbPDA5BwnOiNpiZeX30cgZuzESAfdgrVuQHOIJk4DztUHlM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759938474; c=relaxed/simple; bh=iTPbxraedZD3neNFGfY1HUmZOBnuTBKr9Z6Mu5jfHGE=; h=Date:From:To:Cc:Subject:Message-ID:MIME-Version:Content-Type; b=YpuQqslQZNT3+dZSjtp5pJLDHOqwRt0WDlV7ifcSwH14BB+nwQBtP2zl034YOxRBXTigrP/2jF0g77XMdhSRh2jjLyO45mGNUPQID0c0RPJnVdznxd2xaEbmosaixYXGiOaupTHsRzvkEgJE9vfiENFomZ54FU+HZBkqQZpmJwk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=goodmis.org; spf=pass smtp.mailfrom=goodmis.org; arc=none smtp.client-ip=216.40.44.13 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=goodmis.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=goodmis.org Received: from omf03.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id 5DB2613B347; Wed, 8 Oct 2025 15:47:51 +0000 (UTC) Received: from [HIDDEN] (Authenticated sender: rostedt@goodmis.org) by omf03.hostedemail.com (Postfix) with ESMTPA id 9EC056000D; Wed, 8 Oct 2025 15:47:49 +0000 (UTC) Date: Wed, 8 Oct 2025 11:49:43 -0400 From: Steven Rostedt To: LKML , Linux Trace Kernel Cc: Masami Hiramatsu , Mathieu Desnoyers , Sasha Levin Subject: [PATCH] tracing: Fix irqoff tracers on failure of acquiring calltime Message-ID: <20251008114943.6f60f30f@gandalf.local.home> 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 X-Rspamd-Queue-Id: 9EC056000D X-Stat-Signature: pkk4u41ktrogas6r3u5u1mycyheyho9d X-Rspamd-Server: rspamout02 X-Session-Marker: 726F737465647440676F6F646D69732E6F7267 X-Session-ID: U2FsdGVkX1+rO6qzSFGfBADFEp/Zv/mePxJvGgyc4Zs= X-HE-Tag: 1759938469-557830 X-HE-Meta: U2FsdGVkX1+Likmk7TE9ksRVH3n6t+YtPSlpLPvHiZ/hcW6eNgRNHNpypuG3xqUETUqQNsDUCdY2A/s6gWQHGdGKOTfnL1vVZG7FWF1fJG7ZmFBOhN6pbeThgi0yAgxkhdbWG0+S2AnLJ5DgMLrSTC5DkwlcNAO53UtllWbXXgBLjw0LZMiQUrwi6c6DRCYFtxcV70i8yK6qkNXWg4pc+lTT7LUa6kVaOwL4TYNfsUcoL0FLpFtOVftnky5USYcdVG0/ncUI7HoZCK3g2ojph8RKip6+3sZIEu8ai1D5p7fM7c0wwqIG0bDjQbqYfzNc6SG2xVq8YQy5JCrOHmdB/PXHv6OKy3zYPwA9w57zibhA++ruLjhzn92HgLcP8M+edrQDvwIWBFJbiYngmPDnkg== From: Steven Rostedt The functions irqsoff_graph_entry() and irqsoff_graph_return() both call func_prolog_dec() that will test if the data->disable is already set and if not, increment it and return. If it was set, it returns false and the caller exits. The caller of this function must decrement the disable counter, but misses doing so if the calltime fails to be acquired. Instead of exiting out when calltime is NULL, change the logic to do the work if it is not NULL and still do the clean up at the end of the function if it is NULL. Cc: stable@vger.kernel.org Fixes: a485ea9e3ef3 ("tracing: Fix irqsoff and wakeup latency tracers when using function graph") Reported-by: Sasha Levin Closes: https://lore.kernel.org/linux-trace-kernel/20251006175848.1906912-2-sashal@kernel.org/ Signed-off-by: Steven Rostedt (Google) --- kernel/trace/trace_irqsoff.c | 23 ++++++++++------------- 1 file changed, 10 insertions(+), 13 deletions(-) diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c index 5496758b6c76..4c45c49b06c8 100644 --- a/kernel/trace/trace_irqsoff.c +++ b/kernel/trace/trace_irqsoff.c @@ -184,7 +184,7 @@ static int irqsoff_graph_entry(struct ftrace_graph_ent *trace, unsigned long flags; unsigned int trace_ctx; u64 *calltime; - int ret; + int ret = 0; if (ftrace_graph_ignore_func(gops, trace)) return 0; @@ -202,13 +202,11 @@ static int irqsoff_graph_entry(struct ftrace_graph_ent *trace, return 0; calltime = fgraph_reserve_data(gops->idx, sizeof(*calltime)); - if (!calltime) - return 0; - - *calltime = trace_clock_local(); - - trace_ctx = tracing_gen_ctx_flags(flags); - ret = __trace_graph_entry(tr, trace, trace_ctx); + if (calltime) { + *calltime = trace_clock_local(); + trace_ctx = tracing_gen_ctx_flags(flags); + ret = __trace_graph_entry(tr, trace, trace_ctx); + } local_dec(&data->disabled); return ret; @@ -233,11 +231,10 @@ static void irqsoff_graph_return(struct ftrace_graph_ret *trace, rettime = trace_clock_local(); calltime = fgraph_retrieve_data(gops->idx, &size); - if (!calltime) - return; - - trace_ctx = tracing_gen_ctx_flags(flags); - __trace_graph_return(tr, trace, trace_ctx, *calltime, rettime); + if (calltime) { + trace_ctx = tracing_gen_ctx_flags(flags); + __trace_graph_return(tr, trace, trace_ctx, *calltime, rettime); + } local_dec(&data->disabled); } -- 2.51.0