From nobody Fri Oct 3 18:10:05 2025 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (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 8FDCA2C0272; Wed, 27 Aug 2025 06:45:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756277125; cv=none; b=TcRz1Bxydn+cqc72v42wr/sMsE5Mtx6bpNC4FKA7/hsn8+X9LNQ4mE4aXw3Z2H6OJ1NeJEt1BwYYufpAMck+Mf+g962CX9mRfV/uWniuz7VeNp+uLxG8IG40dORyhxGGW1mRdOZbZr2ARReWS1p0v3ZYefqoCT3Mkzz2jboOQuY= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756277125; c=relaxed/simple; bh=EqeCcCwX5nqul7P1Q38YGdZ3Yzbh6I9p12Bz1xn7RQU=; h=Date:From:To:Subject:Cc:In-Reply-To:References:MIME-Version: Message-ID:Content-Type; b=CR7Qrv1XT0AvM/Ln82z2yipbIlHyb2HdZe1QQ9F6KPSHLyjGZnKS9o/o0aLu8MSL8+umQclJWiNWUy/Rtk5n6n/Pg+Zjqn0SlYkotHm2JeQRWePh1dQkn5s53Qahb4Hrw4YcN2UaZ+CJscA4v7LaGLWHFJ6xerbhIugtjZRoc9g= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=E0e2huWx; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=Cz1fwAVL; arc=none smtp.client-ip=193.142.43.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="E0e2huWx"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="Cz1fwAVL" Date: Wed, 27 Aug 2025 06:45:20 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1756277122; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=s4RP5C2zXVRc8hpDXBWFxVBmI3JnQ44PEExj/NMS7oo=; b=E0e2huWx817stKDZI0JJ5fiwCvZ0Iwx5Eses2dbAjOOJCUgYn4OVEQXKLAe6fsX6kLHkVO b9hkzylAQHqDy7r9YjUifqzYA557U4DsVaFC58Jn6jG3xJvWbBkd6bz/guwWnhaNNBWQzf 8lr1Nmz2OOGZGqksoe0jB5ps0KlkwoEKMh7ND98I6sJNwEE//bB/6MY8G7cMF0Sng6dgI9 8/zUrsVKoFyGJNEMrEtziAl1XlD+TWtQNsu9U0CLXSmJg4G7xIkV/Pp4BGSeWZs8qPCOHV XfTKksxjCspuvWH63pfGcWVGimX6lxZ9SjNlTTMZDFEe1s1zIrMU9vc7lIt/Xw== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1756277122; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=s4RP5C2zXVRc8hpDXBWFxVBmI3JnQ44PEExj/NMS7oo=; b=Cz1fwAVLR1b9SPaAPSGy4owzj1z8hwalzGBTJR2CDR358tM/VfSsh39CqS1VeFEz2CpCao LAcdiD7S9dBDS5CQ== From: "tip-bot2 for Steven Rostedt" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: perf/core] perf: Use current->flags & PF_KTHREAD|PF_USER_WORKER instead of current->mm == NULL Cc: "Steven Rostedt (Google)" , "Peter Zijlstra (Intel)" , x86@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <20250820180428.592367294@kernel.org> References: <20250820180428.592367294@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-ID: <175627712063.1920.17265851610092530439.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Precedence: bulk Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable The following commit has been merged into the perf/core branch of tip: Commit-ID: 90942f9fac05702065ff82ed0bade0d08168d4ea Gitweb: https://git.kernel.org/tip/90942f9fac05702065ff82ed0bade0d08= 168d4ea Author: Steven Rostedt AuthorDate: Wed, 20 Aug 2025 14:03:41 -04:00 Committer: Peter Zijlstra CommitterDate: Tue, 26 Aug 2025 09:51:13 +02:00 perf: Use current->flags & PF_KTHREAD|PF_USER_WORKER instead of current->mm= =3D=3D NULL To determine if a task is a kernel thread or not, it is more reliable to use (current->flags & (PF_KTHREAD|PF_USER_WORKERi)) than to rely on current->mm being NULL. That is because some kernel tasks (io_uring helpers) may have a mm field. Signed-off-by: Steven Rostedt (Google) Signed-off-by: Peter Zijlstra (Intel) Link: https://lore.kernel.org/r/20250820180428.592367294@kernel.org --- kernel/events/callchain.c | 6 +++--- kernel/events/core.c | 4 ++-- 2 files changed, 5 insertions(+), 5 deletions(-) diff --git a/kernel/events/callchain.c b/kernel/events/callchain.c index cd0e3fc..5982d18 100644 --- a/kernel/events/callchain.c +++ b/kernel/events/callchain.c @@ -246,10 +246,10 @@ get_perf_callchain(struct pt_regs *regs, bool kernel,= bool user, =20 if (user && !crosstask) { if (!user_mode(regs)) { - if (current->mm) - regs =3D task_pt_regs(current); - else + if (current->flags & (PF_KTHREAD | PF_USER_WORKER)) regs =3D NULL; + else + regs =3D task_pt_regs(current); } =20 if (regs) { diff --git a/kernel/events/core.c b/kernel/events/core.c index bade8e0..f880cec 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -7446,7 +7446,7 @@ static void perf_sample_regs_user(struct perf_regs *r= egs_user, if (user_mode(regs)) { regs_user->abi =3D perf_reg_abi(current); regs_user->regs =3D regs; - } else if (!(current->flags & PF_KTHREAD)) { + } else if (!(current->flags & (PF_KTHREAD | PF_USER_WORKER))) { perf_get_regs_user(regs_user, regs); } else { regs_user->abi =3D PERF_SAMPLE_REGS_ABI_NONE; @@ -8086,7 +8086,7 @@ static u64 perf_virt_to_phys(u64 virt) * Try IRQ-safe get_user_page_fast_only first. * If failed, leave phys_addr as 0. */ - if (current->mm !=3D NULL) { + if (!(current->flags & (PF_KTHREAD | PF_USER_WORKER))) { struct page *p; =20 pagefault_disable();