From nobody Mon Feb 9 03:10:44 2026 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 983FA26982B; Fri, 2 May 2025 16:50:10 +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=1746204610; cv=none; b=j2A1BUr5smbJBbZg4fqF2lsOHD8gFRCDCnK7NOmM250GFcM3K/yxVl8L5HolsIyt/fUoGkOFmdmhYX/M0sPicFsWB+sK3/rL//OTDUR3H1kOWAgcvs0TJPZwN9g3EXvHzKYIYA2r0lT53gnjmC2vLLXEs48FJsd+MopFbGEyMSM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746204610; c=relaxed/simple; bh=6DE7KZOXrlLO0p0yUtPCwZQ+NilkphXCklG8RJnYqCw=; h=Message-ID:Date:From:To:Cc:Subject:References:MIME-Version: Content-Type; b=b7K2wxHXBJSdJ3cFRzReF2k+xpZkqWk1fp8ITTUwCXOGyIaL+FCRSg1gUtOYwgGBJiT+JESVetfFcBJcFtvvc9dtTP6tIFKXK3DWmqnymv1PlARy2cGqH9qLEMhAxnTYfxsPmHfeZXQ8+xUY34h6erv95ROop8+9xVHpWMhaPr4= 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 7E34BC4CEE9; Fri, 2 May 2025 16:50:10 +0000 (UTC) Received: from rostedt by gandalf with local (Exim 4.98.2) (envelope-from ) id 1uAtaT-0000000036G-3jZv; Fri, 02 May 2025 12:50:09 -0400 Message-ID: <20250502165009.741937086@goodmis.org> User-Agent: quilt/0.68 Date: Fri, 02 May 2025 12:48:00 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org Cc: Masami Hiramatsu , Mathieu Desnoyers , Josh Poimboeuf , Peter Zijlstra , x86@kernel.org, Jiri Olsa , Namhyung Kim Subject: [PATCH v7 14/17] perf: Have get_perf_callchain() return NULL if crosstask and user are set References: <20250502164746.178864972@goodmis.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Josh Poimboeuf 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) --- kernel/events/callchain.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/kernel/events/callchain.c b/kernel/events/callchain.c index b0f5bd228cd8..abf258913ab6 100644 --- a/kernel/events/callchain.c +++ b/kernel/events/callchain.c @@ -224,6 +224,10 @@ get_perf_callchain(struct pt_regs *regs, bool kernel, = bool user, struct perf_callchain_entry_ctx ctx; int rctx, start_entry_idx; =20 + /* crosstask is not supported for user stacks */ + if (crosstask && user) + return NULL; + entry =3D get_callchain_entry(&rctx); if (!entry) return NULL; @@ -249,9 +253,6 @@ get_perf_callchain(struct pt_regs *regs, bool kernel, b= ool user, } =20 if (regs) { - if (crosstask) - goto exit_put; - if (add_mark) perf_callchain_store_context(&ctx, PERF_CONTEXT_USER); =20 @@ -261,7 +262,6 @@ get_perf_callchain(struct pt_regs *regs, bool kernel, b= ool user, } } =20 -exit_put: put_callchain_entry(rctx); =20 return entry; --=20 2.47.2