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 D935025A2B5; Tue, 7 Apr 2026 14:30:09 +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=1775572209; cv=none; b=nW5o5HSASePpB6Xvb/91uJXT9dHryagrKswJ0dQr+8a5AcNLcGUcYF/A0h/k1wcydHDZE30IIiz87NNLJLIQxRwOiBDVdWkPftTy2ExWrHbTHIE9HpM2gS54n9xMS/o2Uncc5PaFHInp6ClYMG4HXCLd8Hu0n5D4IS9E2wh1yx8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775572209; c=relaxed/simple; bh=F6zPippwXT9NoAaPuBCmjQXM7i5cwJ55Lk+dK97iVfo=; h=From:Subject:Date:Message-Id:MIME-Version:Content-Type:To:Cc; b=QI7yCXjsu3Bfqr82+wqMmKmf9v/qyuJKCfblIhakwwPV4I6glhhMr6qzjlF5zTI96VKyt2mLRxEqgyXKT5tHV6SdUDDvYAD+jreMwQiBcHCD8DcBlT6rWox1m3vxZ7WRFCXV39uk5PZVqJ5/xuSlbtxCB+Kpmfu7QHXE8ABq4g0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=SGGpCilo; 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="SGGpCilo" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4B4AFC116C6; Tue, 7 Apr 2026 14:30:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1775572209; bh=F6zPippwXT9NoAaPuBCmjQXM7i5cwJ55Lk+dK97iVfo=; h=From:Subject:Date:To:Cc:From; b=SGGpCiloA16YGCNOBtnjqATKduo9VqxPftvhFTU4wQ99oD6xhZII3QIIPuZ2BteZi It4oNSzT+9TV6imSaukmNALxBbaSIH04pnHw+M6T4s3hbGTZk66/6p4/JDiCZ1VdLA sAQn37Sb6xna/XRQ3bokAGI4LKLj7xAfa4HSGVbr+crUhyoVjTFNNgF0zVgexUITaG 3oO0IctM29eF06Ko+4LKEtWm/Y5wll033MXeJp4amWrRhRc8aRdB9Fsi2Ax/RP3KVY Y8DZqVWkFinHJV507eYo9FG4A3vIba8mdeHmRheb1U4J/C6vnYUKpC5VRqfkbkMLh6 sCi7TVjgfAdYQ== From: "Rob Herring (Arm)" Subject: [PATCH v4 0/6] arm64: Add support for FEAT_Debugv8p9 Date: Tue, 07 Apr 2026 09:29:42 -0500 Message-Id: <20260407-arm-debug-8-9-v4-0-a4864e69b0ea@kernel.org> Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-B4-Tracking: v=1; b=H4sIANYU1WkC/6tWKk4tykwtVrJSqFYqSi3LLM7MzwNyTHQUlJIzE vPSU3UzU4B8JSMDIzMDEwMz3cSiXN2U1KTSdF0LXUtdE8M0szSDVHNjyyRTJaCegqLUtMwKsHn RsbW1ABe/erJfAAAA X-Change-ID: 20260406-arm-debug-8-9-41f6f0e739b5 To: Will Deacon , Mark Rutland , Catalin Marinas , Jonathan Corbet , Shuah Khan Cc: Anshuman Khandual , linux-arm-kernel@lists.infradead.org, linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, Marc Zyngier , kvmarm@lists.linux.dev, Oliver Upton X-Mailer: b4 0.15-dev This series enables FEAT_Debugv8p9 which extends the breakpoint and watchpoint support from 16 up to 64. I've picked up this series from Anshuman. Changes in V4: - Limit enabling of FEAT_Debugv8p9 to only when more than 16 breakpoints or watchpoints are present. - Add lockdep_assert_irqs_disabled() to document the constraints. Drop unnecessary IRQ disabling. - Add more kprobe blacklist annotations and disallow breakpoints in the nokprobe code. - Drop previously applied sysreg patches. Prior versions from Anshuman: Changes in V3: https://lore.kernel.org/all/20241216040831.2448257-1-anshuman.khandual@arm.com/ - Marked ID_AA64DFR1_EL1.ABLE as FTR_NONSTRICT in ftr_id_aa64dfr1[] - Dropped MDCR_EL3.TDA boot requirement from documentation (separate series) - Dropped MDCR_EL2_EBWE definition as MDCR_EL2 is now defined in tools sysreg - Used SYS_FIELD_PREP() in read_wb_reg() and write_wb_reg() - Added MAX_PER_BANK based BUILD_BUG_ON() tests in arch_hw_breakpoint_init() - Dropped local variables i.e mdsel_bank and index - Derived bank and index from MAX_PER_BANK as required Changes in V2: https://lore.kernel.org/all/20241028053426.2486633-1-anshuman.khandual@arm.com/ Following changes have been made per review comments from Mark Rutland - Orr MDCR_EL2_EBWE directly without an intermittent register - Alphabetically order header files in debug-monitors.c - Dropped embwe_ref_count mechanism - Dropped preempt_enable() from AARCH64_DBG_READ - Dropped preempt_disable() from AARCH64_DBG_WRITE - Dropped set_bank_index() - Renamed read/write_wb_reg() as __read/__write_wb_reg() - Modified read/write_wb_reg() to have MDSELR_E1 based banked read/write - Added required sysreg tools patches from KVM FEAT_FGT2 series for build Changes in V1: https://lore.kernel.org/all/20241001043602.1116991-1-anshuman.khandual@arm.com/ - Changed FTR_STRICT to FTR_NONSTRICT for the following ID_AA64DFR1_EL1 register fields - ABL_CMPs, DPFZS, PMICNTR, CTX_CMPs, WRPs and BRPs Changes in RFC V2: https://lore.kernel.org/linux-arm-kernel/20240620092607.267132-1-anshuman.khandual@arm.com/ - This series has been split from RFC V1 dealing only with arm64 breakpoints - Restored back DBG_MDSCR_MASK definition (unrelated change) - Added preempt_disable()/enable() blocks between selecting banks and registers Changes in RFC: https://lore.kernel.org/all/20240405080008.1225223-1-anshuman.khandual@arm.com/ Signed-off-by: Rob Herring (Arm) --- Anshuman Khandual (3): arm64/cpufeature: Add field details for ID_AA64DFR1_EL1 register arm64/boot: Enable EL2 requirements for FEAT_Debugv8p9 arm64: hw_breakpoint: Enable FEAT_Debugv8p9 Rob Herring (Arm) (3): arm64: hw_breakpoint: Disallow breakpoints in no kprobe code arm64: hw_breakpoint: Add additional kprobe excluded functions arm64: hw_breakpoint: Add lockdep_assert_irqs_disabled() on install/uninstall Documentation/arch/arm64/booting.rst | 13 +++++++ arch/arm64/include/asm/el2_setup.h | 14 +++++++ arch/arm64/include/asm/hw_breakpoint.h | 47 ++++++++++++++++++----- arch/arm64/kernel/cpufeature.c | 21 ++++++++--- arch/arm64/kernel/debug-monitors.c | 16 +++++--- arch/arm64/kernel/hw_breakpoint.c | 68 +++++++++++++++++++++++++++++----- 6 files changed, 150 insertions(+), 29 deletions(-) --- base-commit: 6de23f81a5e08be8fbf5e8d7e9febc72a5b5f27f change-id: 20260406-arm-debug-8-9-41f6f0e739b5 Best regards, -- Rob Herring (Arm)