From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 C8C1C3F3265; Mon, 17 Aug 2026 14:35:16 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786977318; cv=none; b=Vnyf/iXHNipM1jjyyjOECbYCFfKCXSmZYy5BtD1hNxKQkkBMWYdlRyvrnzrvRHiSth8R92sB7uR1hwY7OJDCZ/sZ8N8ns5ftaO7VOhKY9QoSW4JSc/P3E/HorOCclgpDrotIyXz90sHYikpyJPaakua84KDdBLqfP9QeNgYpBDQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786977318; c=relaxed/simple; bh=vgU+gRfpyan+CDrrb2uzsy0k8YevNdyUCoGzq9voINA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=VCBW66zm7JTTzQ4Xb7xi02gwOnidrCO99Q4ocbRqklFltv8aYadwSfnNe+ZAFZPDm5kGOKBF2Gia0lBpPE4kjqkZ8a2sO7J/vkLlHuTqErkbhBPx/B64vfe6FknzHst08YQv8KjZlctDBlFbf7lV7+NO3SvYex8Uu9LZWoI0/EA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=RMIYNixI; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="RMIYNixI" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2704D1F00A3A; Mon, 17 Aug 2026 14:35:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1786977315; bh=8r3mi7P15u9NYF1E8H51lYgoA6JyaIbh9tiUJHuYyIs=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=RMIYNixIBJJwIonpZFOessdBmRSPeT/bQ+xrwav0M3lEZJ2MTSpcNmAnrkoa8XMPa vWJdgt1k3an+peDDvXgH79K59vsXBRHOC59d2xTv2LilXLnPNqcCqctBcrJFeLhuIP EpBK8cNOQwtgkwP0JSwvdLOvkD4DKeHm6V6fPuzo= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, "Masami Hiramatsu (Google)" , Steven Rostedt , Sasha Levin Subject: [PATCH 5.15 287/456] tracing/mmiotrace: Reset dropped_count in mmio_reset_data() Date: Mon, 17 Aug 2026 15:31:17 +0200 Message-ID: <20260817132551.125515580@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260817132539.792407575@linuxfoundation.org> References: <20260817132539.792407575@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 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Masami Hiramatsu (Google) [ Upstream commit c786d2bdf1f3964deee192ad942dee2a741c1e2c ] mmio_reset_data() is called during tracer initialization, reset, and start. While it resets overrun_detected and prev_overruns, it neglects to reset dropped_count. Consequently, dropped event counts from prior tracing sessions persist in dropped_count and corrupt overrun reports in subsequent runs. Fix this by explicitly calling atomic_set(&dropped_count, 0) in mmio_reset_data(). Link: https://patch.msgid.link/178524299122.56416.16277704230639425172.stgit@devnote2 Fixes: 173ed24ee2d6 ("mmiotrace: count events lost due to not recording") Assisted-by: Antigravity:gemini-3.6-flash Signed-off-by: Masami Hiramatsu (Google) Signed-off-by: Steven Rostedt Signed-off-by: Sasha Levin --- kernel/trace/trace_mmiotrace.c | 1 + 1 file changed, 1 insertion(+) diff --git a/kernel/trace/trace_mmiotrace.c b/kernel/trace/trace_mmiotrace.c index 4d9e5c830dbe1..c523ce5aa4958 100644 --- a/kernel/trace/trace_mmiotrace.c +++ b/kernel/trace/trace_mmiotrace.c @@ -29,6 +29,7 @@ static void mmio_reset_data(struct trace_array *tr) { overrun_detected = false; prev_overruns = 0; + atomic_set(&dropped_count, 0); tracing_reset_online_cpus(&tr->array_buffer); } -- 2.53.0