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 1819022A4D6; Fri, 31 Oct 2025 14:05:44 +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=1761919544; cv=none; b=HAlbDsFLJZLSVF9wnLUr/K/vKnElk5azzij/uElwi19pkffpLdOGxiKa26Qp0mhMdrZ2GoSaCzW3DEifI4Ll32EAgI29NGWJy3PqbB3ugx4sRe3eGrUJqxn9oXtAL8SuJo0cDRuCn6hovjR4nzW3bGJBzh22RlPqB3EBdHg83wM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761919544; c=relaxed/simple; bh=Ep8ttPbCAdYc8+RFZ7M94sPSuZGu1VwsK+EpeDQ7APM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=NgG7A9QsUvkrlfQ8fNb8PFSLLmiNV9n4JaSw7cM8wOCNGxz6vOroD5UjMa9L9XHFSGN2y6B40DgE27Dq2Mez8eXZxhZMaZAIkB3VY9B3R13UVqIKCH+1hI+86B/+AEQsD1JaGeTQHxE1U9SKQKgFiuzjQenO7R9eLeupEiiKG/4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=KZB2QWUV; 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="KZB2QWUV" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6B1D5C4CEE7; Fri, 31 Oct 2025 14:05:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1761919544; bh=Ep8ttPbCAdYc8+RFZ7M94sPSuZGu1VwsK+EpeDQ7APM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=KZB2QWUVCzO4D3UpgCWynI2zpm7nd7/a6c8YswH9Gh7EYrObnoo8VE5eAkqTRjFV+ 8BoTaQZIZUI7Uh/CBlLlTxtgKlBnOmas/3msiMu5QIaLVQ2M9HJSGx6CdhLzHLF6Pz Y/ukjrB2SJawEfkNRLX6MaSPHzYgW8ZBc0M5ucp0= 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 6.17 14/35] perf: Have get_perf_callchain() return NULL if crosstask and user are set Date: Fri, 31 Oct 2025 15:01:22 +0100 Message-ID: <20251031140043.901751352@linuxfoundation.org> X-Mailer: git-send-email 2.51.2 In-Reply-To: <20251031140043.564670400@linuxfoundation.org> References: <20251031140043.564670400@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 6.17-stable review patch. If anyone has any objections, please let me know. ------------------ From: Josh Poimboeuf [ Upstream commit 153f9e74dec230f2e070e16fa061bc7adfd2c450 ] get_perf_callchain() doesn't support cross-task unwinding for user space stacks, have it return NULL if both the crosstask and user arguments are set. Signed-off-by: Josh Poimboeuf Signed-off-by: Steven Rostedt (Google) Signed-off-by: Peter Zijlstra (Intel) Link: https://lore.kernel.org/r/20250820180428.426423415@kernel.org Signed-off-by: Sasha Levin --- kernel/events/callchain.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/kernel/events/callchain.c b/kernel/events/callchain.c index decff7266cfbd..2609998ca07f1 100644 --- a/kernel/events/callchain.c +++ b/kernel/events/callchain.c @@ -224,6 +224,10 @@ get_perf_callchain(struct pt_regs *regs, u32 init_nr, bool kernel, bool user, struct perf_callchain_entry_ctx ctx; int rctx, start_entry_idx; + /* crosstask is not supported for user stacks */ + if (crosstask && user && !kernel) + return NULL; + entry = get_callchain_entry(&rctx); if (!entry) return NULL; @@ -240,7 +244,7 @@ get_perf_callchain(struct pt_regs *regs, u32 init_nr, bool kernel, bool user, perf_callchain_kernel(&ctx, regs); } - if (user) { + if (user && !crosstask) { if (!user_mode(regs)) { if (current->flags & (PF_KTHREAD | PF_USER_WORKER)) regs = NULL; @@ -249,9 +253,6 @@ get_perf_callchain(struct pt_regs *regs, u32 init_nr, bool kernel, bool user, } if (regs) { - if (crosstask) - goto exit_put; - if (add_mark) perf_callchain_store_context(&ctx, PERF_CONTEXT_USER); @@ -261,7 +262,6 @@ get_perf_callchain(struct pt_regs *regs, u32 init_nr, bool kernel, bool user, } } -exit_put: put_callchain_entry(rctx); return entry; -- 2.51.0