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 1973822A4D6; Fri, 31 Oct 2025 14:05:41 +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=1761919541; cv=none; b=FsEbin4aqYofd7trmwK6XLTWLPyziuWsLXUfzYW97kO20iVFLUBeBlEXQ9MEvxbCetB2+ey+bbByhs0GnnPOEgVNo8OflIA02y8yxSAYoZbMN/+Qz6dTvMB5nwVj6Na7XOvwe3POvQB0V47EcWOxRmL4nvGdh60fEajAxRhXCik= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761919541; c=relaxed/simple; bh=H0BTvXIHfv54WGbD/a0VKztSIOcJNQi+mQgVpsnfRRI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=rsu9cJKIDQRXIlhaRVgvtaCkHkvbtx83O7l0RAGu+q8kqe98R9OGDslJ2L0WhiOS9OktW/jbfgTjI3L+h7Dmwrph4eZmyD9V7UMSCV/71oxg5e3qEKf/zaJPH4dE9WirWSFefh7bGabV+YHmW16PUVYU3NVr4kBhqAN0o7fhsyQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=0YQBptRm; 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="0YQBptRm" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8CA18C4CEE7; Fri, 31 Oct 2025 14:05:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1761919541; bh=H0BTvXIHfv54WGbD/a0VKztSIOcJNQi+mQgVpsnfRRI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=0YQBptRmOq5b0VpOD8jPGqEr6I/bbKlrcB8J+5Cv/8sRM6/6WqNH4wEjao8y4F9P1 4o2qr1hPX4AxjbS5kWJu7Ii0dv+0DF09azjCJ0ufvkiUghH+bYvlswKStFOXDgxlEJ kelhhkrUArlPGi4f2XdFygTkZ5/o74fr5FWc5Kxw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, "Steven Rostedt (Google)" , "Peter Zijlstra (Intel)" , Sasha Levin Subject: [PATCH 6.17 13/35] perf: Use current->flags & PF_KTHREAD|PF_USER_WORKER instead of current->mm == NULL Date: Fri, 31 Oct 2025 15:01:21 +0100 Message-ID: <20251031140043.876231714@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: Steven Rostedt [ Upstream commit 90942f9fac05702065ff82ed0bade0d08168d4ea ] 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 Signed-off-by: Sasha Levin --- 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 6c83ad674d010..decff7266cfbd 100644 --- a/kernel/events/callchain.c +++ b/kernel/events/callchain.c @@ -242,10 +242,10 @@ get_perf_callchain(struct pt_regs *regs, u32 init_nr, bool kernel, bool user, if (user) { if (!user_mode(regs)) { - if (current->mm) - regs = task_pt_regs(current); - else + if (current->flags & (PF_KTHREAD | PF_USER_WORKER)) regs = NULL; + else + regs = task_pt_regs(current); } if (regs) { diff --git a/kernel/events/core.c b/kernel/events/core.c index 6e9427c4aaff7..a3dc79ec6f879 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -7440,7 +7440,7 @@ static void perf_sample_regs_user(struct perf_regs *regs_user, if (user_mode(regs)) { regs_user->abi = perf_reg_abi(current); regs_user->regs = 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 = PERF_SAMPLE_REGS_ABI_NONE; @@ -8080,7 +8080,7 @@ 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 != NULL) { + if (!(current->flags & (PF_KTHREAD | PF_USER_WORKER))) { struct page *p; pagefault_disable(); -- 2.51.0