From patchwork Tue Mar 26 13:46:16 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jarkko Sakkinen X-Patchwork-Id: 13604227 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 E91FD80636; Tue, 26 Mar 2024 13:46:27 +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=1711460788; cv=none; b=AjAqxsNqp189ODKGFvO90ay0WjyyBA7GFa1cNRjrr9IuQw6g83WvUBZW3sbIRRTP/YQ9YvZKxO5K76MtQGAmz1Izjh0mBKuFe47gWsGeLuDE2UWIF3kZHPumVWiRdvEfQKvlvDwH3rXosqamQ006Euz506SGanYU8lXWnhNtU6k= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711460788; c=relaxed/simple; bh=c6NsflThbm35b0SKCPPV8/Xpu3AsAtft7sHECHTKMb0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=YIHE9PezC0T37xfmubFFHS9LQ/y8f5oYdWn0IYD5p/pzUqVku3VGEHPUnHYKhTG2OqwKtMfbOsDaGksO0a9/zovjCWg/60Oy3lP10+nHpK7sWrDHdbCe4F88GfYk2wrB9q/FDUNrGGEEYf80r7tX52PaAyCgXMkBRToRJK1Rf/g= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=dQxR19kU; 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="dQxR19kU" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E2570C433F1; Tue, 26 Mar 2024 13:46:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1711460787; bh=c6NsflThbm35b0SKCPPV8/Xpu3AsAtft7sHECHTKMb0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=dQxR19kUI/H7grr74pRJUFaRwgo9ZhXq3MjHzsEW6QcrzWO75pJIsjW9M7GjDwRzu JYFkoGyIdTRLH0A2nKzAzm1lCclxTSCDmEJjliUlFBnsOl/ik3v8IrKVdU4bH0htE2 v8BGxvkRlTh+hkv6X4gPUQHncxqMIArn5pir4r/lMyIgigvS7+7pWrjFtzZZBIUMMj u+5Kooy4o7nLfytPnvUM0koJceOdnlR6Ya7AT3chNdXCSfCdNhMb1xDxfpsX+CKHd4 pBjwkAhuCnABA7UjJNBRDpWkgMhaJuYklUAD/KjPZF9r8d3AzDw7ESWbmNA3/6RV/c BDmqP0hpTeplw== 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 v7 2/2] arch/riscv: Enable kprobes when CONFIG_MODULES=n Date: Tue, 26 Mar 2024 15:46:16 +0200 Message-ID: <20240326134616.7691-2-jarkko@kernel.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240326134616.7691-1-jarkko@kernel.org> References: <20240326134616.7691-1-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 --- v5-v7: - No changes. 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); +}