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 82D8DAD4B; Fri, 31 Oct 2025 14:02:34 +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=1761919354; cv=none; b=astu+/u/A+LU1DlYPnF25sKqD5Kz2FQp07VM5hHBN9wDj7/c26xcOHKQxKYa/MPr9kGdBxngslI1y49U7xuxx7QW9tuZpKSUigqIBPoD8lVwbmtBmKJ+pettFVXNgt8l1BAIX42dYlGjdJNVdp/EJRJ6Gs2qF/UxPwvPxP9gUd4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761919354; c=relaxed/simple; bh=JX+5Pwk+Ap45tM2AI6zlx2eKiMnqR9aPSJwL8Y0NEfc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=R3C9nvynjEO627GTXg7cycksLeDE/ierOXeLPLS1zXBG2k/SySc2dKwoIn9RW/mmE1ZFYeeXj70Zt1pPcbAHjfPXYXadFPFjZqJRsMzfZ0lkYucluy3wEG/duPjz2OSSxMXTZfnp++QGJytV5dgz01aV+1Qxh5BLIJUndv68IwI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=jn6Tq11k; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="jn6Tq11k" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0E337C4CEFB; Fri, 31 Oct 2025 14:02:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1761919354; bh=JX+5Pwk+Ap45tM2AI6zlx2eKiMnqR9aPSJwL8Y0NEfc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jn6Tq11kTWva2FNC+G6HPWwUATb6nj01kFrgA9N7mjoIANvTe7UBRWKeueV9j/O6c znWHL8vzu3i7MAbAD5oLovVUCBWxGxjs9I9ax4neUWgC7tqjsFWGSOCL6zkyER1qG4 B6QaEcthMUYfhzHmiSaUYRgQopuTpoMrfXbQNVG0= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Josh Poimboeuf , "Steven Rostedt (Google)" , "Peter Zijlstra (Intel)" , Sasha Levin Subject: [PATCH 6.6 05/32] perf: Skip user unwind if the task is a kernel thread Date: Fri, 31 Oct 2025 15:00:59 +0100 Message-ID: <20251031140042.529430263@linuxfoundation.org> X-Mailer: git-send-email 2.51.2 In-Reply-To: <20251031140042.387255981@linuxfoundation.org> References: <20251031140042.387255981@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 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Josh Poimboeuf [ Upstream commit 16ed389227651330879e17bd83d43bd234006722 ] If the task is not a user thread, there's no user stack to unwind. Signed-off-by: Josh Poimboeuf Signed-off-by: Steven Rostedt (Google) Signed-off-by: Peter Zijlstra (Intel) Link: https://lore.kernel.org/r/20250820180428.930791978@kernel.org Signed-off-by: Sasha Levin --- kernel/events/core.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/events/core.c b/kernel/events/core.c index 3eb9125431b43..c9a3fb6fdb2f6 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -7724,7 +7724,8 @@ struct perf_callchain_entry * perf_callchain(struct perf_event *event, struct pt_regs *regs) { bool kernel = !event->attr.exclude_callchain_kernel; - bool user = !event->attr.exclude_callchain_user; + bool user = !event->attr.exclude_callchain_user && + !(current->flags & (PF_KTHREAD | PF_USER_WORKER)); /* Disallow cross-task user callchains. */ bool crosstask = event->ctx->task && event->ctx->task != current; const u32 max_stack = event->attr.sample_max_stack; -- 2.51.0