From patchwork Tue Mar 26 01:21:02 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jarkko Sakkinen X-Patchwork-Id: 13603225 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 5C4BF1CD3F; Tue, 26 Mar 2024 01:21:12 +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=1711416072; cv=none; b=WsdV01Y29OnMbOUW8C6RjM4Qbsw9jt62tg5ZT6BjXjf/gJkJx3MMJ0IcJvB484LhYRfvGgaazB88kK2001FvxXdJusm2nYswtfWtI0xs/VoNQ101romfaztrKSKItIhZjxgHEVyS9DfcMza5PVtOc/XKSvOpGtUiJyxAHAWFf3o= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711416072; c=relaxed/simple; bh=oxc669xa4HArX18pe0zMZ3KIpnQmQJWwkeqzhcN8JkQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=uiPLMSlWxTl28carax7u9xlDgyd8ZWTVS5l2lAgwI7vBDrnS+5UM6g5av11PR3A/cQqfOjILtycZdC/9qrvyJRHqNVIt1xczt6m3WHiNYtVKN6XooC1GOGxr876az/jQ633fmHwKcGOCOy0fh9Cya1n8b3S3h+JvQ2SyilMjAh8= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=VByYMOgn; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="VByYMOgn" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 576DAC433F1; Tue, 26 Mar 2024 01:21:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1711416071; bh=oxc669xa4HArX18pe0zMZ3KIpnQmQJWwkeqzhcN8JkQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VByYMOgnCP2iCf/wIvMGIWEZ4efp6NKR1i70mSvBsSMDbQX/BMpoSESqMLQLC+dCu Lttm79WU10PxVme+2sNIuUct8OAHnNjEAq/eg6C6/CBSLhAUQ7VqshB/vdVJdVFyZF OEY1sqJOQRV0KQ8XA462AGjzqXZa+p2s3roU9VwZOZ2H34LHiH8vtbBQcJlrYkGmH8 M4PKUXsTcaYDQCwCZxPhMT3g9b1AqE8+XTLQ7t/omtIYeje7yu6EpzGpLzLd6CsvPY 9LHe4AWYk0vXwKlhIaKm6P2VK14F47fMOXH03DiGDrI5nS/8J/7Qk9FvsWH2K25zWo GPL8moZhjgeJg== From: Jarkko Sakkinen To: linux-riscv@lists.infradead.org Cc: Jarkko Sakkinen , Paul Walmsley , Palmer Dabbelt , Albert Ou , linux-kernel@vger.kernel.org, Luis Chamberlain , linux-modules@vger.kernel.org, "Naveen N . Rao" , Anil S Keshavamurthy , "David S . Miller" , Masami Hiramatsu Subject: [PATCH v6 2/2] arch/riscv: Enable kprobes when CONFIG_MODULES=n Date: Tue, 26 Mar 2024 03:21:02 +0200 Message-ID: <20240326012102.27438-2-jarkko@kernel.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240326012102.27438-1-jarkko@kernel.org> References: <20240326012102.27438-1-jarkko@kernel.org> Precedence: bulk X-Mailing-List: linux-modules@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Tacing with kprobes while running a monolithic kernel is currently impossible due the kernel module allocator dependency. Address the issue by implementing textmem API for RISC-V. Link: https://www.sochub.fi # for power on testing new SoC's with a minimal stack Link: https://lore.kernel.org/all/20220608000014.3054333-1-jarkko@profian.com/ # continuation Signed-off-by: Jarkko Sakkinen --- v4: - Include linux/execmem.h. v3: - Architecture independent parts have been split to separate patches. - Do not change arch/riscv/kernel/module.c as it is out of scope for this patch set now. v2: - Better late than never right? :-) - Focus only to RISC-V for now to make the patch more digestable. This is the arch where I use the patch on a daily basis to help with QA. - Introduce HAVE_KPROBES_ALLOC flag to help with more gradual migration. --- arch/riscv/Kconfig | 1 + arch/riscv/kernel/Makefile | 3 +++ arch/riscv/kernel/execmem.c | 22 ++++++++++++++++++++++ 3 files changed, 26 insertions(+) create mode 100644 arch/riscv/kernel/execmem.c diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index e3142ce531a0..499512fb17ff 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -132,6 +132,7 @@ config RISCV select HAVE_KPROBES if !XIP_KERNEL select HAVE_KPROBES_ON_FTRACE if !XIP_KERNEL select HAVE_KRETPROBES if !XIP_KERNEL + select HAVE_ALLOC_EXECMEM if !XIP_KERNEL # https://github.com/ClangBuiltLinux/linux/issues/1881 select HAVE_LD_DEAD_CODE_DATA_ELIMINATION if !LD_IS_LLD select HAVE_MOVE_PMD diff --git a/arch/riscv/kernel/Makefile b/arch/riscv/kernel/Makefile index 604d6bf7e476..337797f10d3e 100644 --- a/arch/riscv/kernel/Makefile +++ b/arch/riscv/kernel/Makefile @@ -73,6 +73,9 @@ obj-$(CONFIG_SMP) += cpu_ops.o obj-$(CONFIG_RISCV_BOOT_SPINWAIT) += cpu_ops_spinwait.o obj-$(CONFIG_MODULES) += module.o +ifeq ($(CONFIG_ALLOC_EXECMEM),y) +obj-y += execmem.o +endif obj-$(CONFIG_MODULE_SECTIONS) += module-sections.o obj-$(CONFIG_CPU_PM) += suspend_entry.o suspend.o diff --git a/arch/riscv/kernel/execmem.c b/arch/riscv/kernel/execmem.c new file mode 100644 index 000000000000..3e52522ead32 --- /dev/null +++ b/arch/riscv/kernel/execmem.c @@ -0,0 +1,22 @@ +// SPDX-License-Identifier: GPL-2.0-or-later + +#include +#include +#include +#include + +void *alloc_execmem(unsigned long size, gfp_t /* gfp */) +{ + return __vmalloc_node_range(size, 1, MODULES_VADDR, + MODULES_END, GFP_KERNEL, + PAGE_KERNEL, 0, NUMA_NO_NODE, + __builtin_return_address(0)); +} + +void free_execmem(void *region) +{ + if (in_interrupt()) + pr_warn("In interrupt context: vmalloc may not work.\n"); + + vfree(region); +}