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 679232D2483 for ; Sun, 14 Dec 2025 08:47:56 +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=1765702076; cv=none; b=p28r4LABbB246JGl3bayB0OFWeFbglaV+AesFzzhWt3/t1mDxkRM7kBcPISeJQdwNV7JqPsYa2xEkWVmpkMowdXlAdBPPHnSlBoVhOrUWx58iN1rus9+R9Y8KDJJymgLMkRDK1wdgs+1VU/zGJnAmolXR919I2+WbFWm76EOCfY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765702076; c=relaxed/simple; bh=pO2rrhCNt/5Y3XRCSvN45526PKlyB+Ni48LJd0E83No=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=BmDtoqmbTDk5LeJC8ueCWdClWkV4QXrU0y1q6vqenR1DZyxO617wT1Qp+CUs2ecV7MBG9yHoW5ZVGj9RfllFcALS33AT3gG1wS++PQQtEv9c4GTD2jcDUkPao3MiWt+7ZAprpvRmVPONPHv3XKcPi+FX29YbBzmEzbxqF+taPds= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=IhVmEyf4; 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="IhVmEyf4" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E7C1FC4CEF1; Sun, 14 Dec 2025 08:47:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1765702076; bh=pO2rrhCNt/5Y3XRCSvN45526PKlyB+Ni48LJd0E83No=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=IhVmEyf4Pn6niuzgF+I4mISzSZATa8dcOvrO2fVrjhsHT1A6ZN1zZnHqhBWv8uQ83 7DyEJGMAGFsLivMA9hK49BzV5g8xuItxYH9B2FSM7cP9jL45zvqi/4m7WBdAiOddn4 vhZNgsRa5zr4wK+XHxvFAK7yV4QCgv0RWUm1B9ckn5OH1KLpIVN0FDZxmxNcAESXuL 469ZKzCfugF6zrDyExScQhHkTDatEElD/L0BJ/nFy+/ND8zuCGGfsaAUvTwzZf02Ne cq4PGAVjLAJl0LObSpZ7qbHH0k+gxKHyWz6nGHQXMWLjKqTVDVnunJXtsqJjvvrxWs 9rCW6wrJZGcJw== From: Ingo Molnar To: linux-kernel@vger.kernel.org Cc: Ingo Molnar , "Ahmed S . Darwish" , Andrew Cooper , Ard Biesheuvel , Arnd Bergmann , Borislav Petkov , Dave Hansen , "H . Peter Anvin" , John Ogness , Linus Torvalds , Peter Zijlstra , Thomas Gleixner , Arnd Bergmann Subject: [PATCH 09/15] x86/fpu: Remove the 'no387' boot option Date: Sun, 14 Dec 2025 09:46:57 +0100 Message-ID: <20251214084710.3606385-10-mingo@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20251214084710.3606385-1-mingo@kernel.org> References: <20251214084710.3606385-1-mingo@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Without math emulation there's no point to this option. Signed-off-by: Ingo Molnar Reviewed-by: Arnd Bergmann Acked-by: Dave Hansen Cc: Ahmed S . Darwish Cc: Andrew Cooper Cc: Ard Biesheuvel Cc: H . Peter Anvin Cc: John Ogness Cc: Linus Torvalds Cc: Peter Zijlstra Link: https://lore.kernel.org/r/20250425084216.3913608-10-mingo@kernel.org --- Documentation/admin-guide/kernel-parameters.txt | 4 ---- arch/x86/Kconfig | 20 +++++++++----------- arch/x86/kernel/cpu/common.c | 7 ------- 3 files changed, 9 insertions(+), 22 deletions(-) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index a8d0afde7f85..9da4c7bba5c5 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -4340,10 +4340,6 @@ Kernel parameters These settings can be accessed at runtime via the nmi_watchdog and hardlockup_panic sysctls. - no387 [BUGS=X86-32] Tells the kernel to use the 387 maths - emulation library even if a 387 maths coprocessor - is present. - no4lvl [RISCV,EARLY] Disable 4-level and 5-level paging modes. Forces kernel to use 3-level paging instead. diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 60a03b61214a..90ec7f2cda93 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -2730,18 +2730,16 @@ menuconfig APM 1) make sure that you have enough swap space and that it is enabled. 2) pass the "idle=poll" option to the kernel - 3) switch on floating point emulation in the kernel and pass - the "no387" option to the kernel - 4) pass the "floppy=nodma" option to the kernel - 5) pass the "mem=4M" option to the kernel (thereby disabling + 3) pass the "floppy=nodma" option to the kernel + 4) pass the "mem=4M" option to the kernel (thereby disabling all but the first 4 MB of RAM) - 6) make sure that the CPU is not over clocked. - 7) read the sig11 FAQ at - 8) disable the cache from your BIOS settings - 9) install a fan for the video card or exchange video RAM - 10) install a better fan for the CPU - 11) exchange RAM chips - 12) exchange the motherboard. + 5) make sure that the CPU is not over clocked. + 6) read the sig11 FAQ at + 7) disable the cache from your BIOS settings + 8) install a fan for the video card or exchange video RAM + 9) install a better fan for the CPU + 10) exchange RAM chips + 11) exchange the motherboard. To compile this driver as a module, choose M here: the module will be called apm. diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index e7ab22fce3b5..0f2a869fb0e6 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -1715,13 +1715,6 @@ static void __init cpu_parse_early_param(void) int arglen; #ifdef CONFIG_X86_32 - if (cmdline_find_option_bool(boot_command_line, "no387")) -#ifdef CONFIG_MATH_EMULATION - setup_clear_cpu_cap(X86_FEATURE_FPU); -#else - pr_err("Option 'no387' required CONFIG_MATH_EMULATION enabled.\n"); -#endif - if (cmdline_find_option_bool(boot_command_line, "nofxsr")) setup_clear_cpu_cap(X86_FEATURE_FXSR); #endif -- 2.51.0