From patchwork Tue Mar 18 20:48:34 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeremy Linton X-Patchwork-Id: 14021527 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 437031F3FDC; Tue, 18 Mar 2025 20:48:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742330934; cv=none; b=jJfq8YhVjMA7AoHP29IEEgkD97yPKw15V65eTJ12TRFKLtrrz0EeaTOJGJB47Yn3agD/j26SIb45ryLTykpKUM8hz/qdgbFOs7skt8Ced0X8IBUFMGfoYnNPOA66Po7NP9YVNoReHjdqDVmS9jIr+8aucaugNKtpguLWPRpTX/U= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742330934; c=relaxed/simple; bh=Onx+0LsIZ2ltycXQSzL79FM6FqL0cWVeyD1K2eT+kq4=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=ghzQEpH+4U+Zo+TDeCGlOi5feXgaBYTTo/jgV28wc79MvcIj7O7buZrYxvJJoYlZSQvIVi0bcdUV68yA4cEQII4KOftwQnB9rUKXoJp7hE/zeTPT4mCLyIqfPhXe/5bmC4whk+y1YUvQBBajHa+Hmyix6r53JE7X1e4m8wsnzoE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 8E7DF13D5; Tue, 18 Mar 2025 13:48:59 -0700 (PDT) Received: from u200865.usa.arm.com (usa-sjc-mx-foss1.foss.arm.com [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 97D0A3F694; Tue, 18 Mar 2025 13:48:50 -0700 (PDT) From: Jeremy Linton To: linux-trace-kernel@vger.kernel.org Cc: linux-perf-users@vger.kernel.org, mhiramat@kernel.org, oleg@redhat.com, peterz@infradead.org, acme@kernel.org, namhyung@kernel.org, mark.rutland@arm.com, alexander.shishkin@linux.intel.com, jolsa@kernel.org, irogers@google.com, adrian.hunter@intel.com, kan.liang@linux.intel.com, thiago.bauermann@linaro.org, broonie@kernel.org, yury.khrustalev@arm.com, kristina.martsenko@arm.com, liaochang1@huawei.com, catalin.marinas@arm.com, will@kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Jeremy Linton Subject: [PATCH 0/7] arm64: Enable UPROBES with GCS Date: Tue, 18 Mar 2025 15:48:34 -0500 Message-ID: <20250318204841.373116-1-jeremy.linton@arm.com> X-Mailer: git-send-email 2.48.1 Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Currently uprobes and the Arm Guarded Control Stack (GCS) feature are exclusive of each other. This restriction needs to be lifted in order to utilize GCS for generic Linux distro images where the expectation is that core debugging features like uprobes work. This series adds some user accessors to read/push/pop the userspace shadow stack. It then utilizes those functions in the uprobe paths as needed to synchronize GCS with the changes in control flow at probe locations. Along the way we fix a bug in the core gcs task handling and export some uprobe quality of life functionality for use in arch specific code. The KCONFIG restriction is then dropped. Jeremy Linton (7): arm64/gcs: task_gcs_el0_enable() should use passed task arm64: probes: Break ret out from bl/blr arm64: uaccess: Add additional userspace GCS accessors arm64: probes: Add GCS support to bl/blr/ret arm64: uprobes: Add GCS support to uretprobes uprobes: Allow the use of uprobe_warn() in arch code arm64: Kconfig: Remove GCS restrictions on UPROBES arch/arm64/Kconfig | 1 - arch/arm64/include/asm/gcs.h | 2 +- arch/arm64/include/asm/uaccess.h | 42 ++++++++++++++++++++++++ arch/arm64/kernel/probes/decode-insn.c | 7 ++-- arch/arm64/kernel/probes/simulate-insn.c | 42 +++++++++++++++++++++--- arch/arm64/kernel/probes/simulate-insn.h | 3 +- arch/arm64/kernel/probes/uprobes.c | 34 +++++++++++++++++++ include/linux/uprobes.h | 1 + kernel/events/uprobes.c | 2 +- 9 files changed, 122 insertions(+), 12 deletions(-)