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 F16E553AC for ; Sat, 30 Mar 2024 03:31:14 +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=1711769475; cv=none; b=HYBWnL8A6EdtMnhsj9X4HN121DKHHyV449kiK2ThOiJoSvVS4f2S88FDAY70gP5H1rZBrUnkJT2rxqBbd0eqH6QF1gG0A/IOUYciK2hBbc1W0iaFgmbR1FCYYFe6Sk+nGui2UEgCgwz6fDFR3bBGKmtUKl+S5q1g91f9OiPI6Ro= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711769475; c=relaxed/simple; bh=H0Q1GoocdxkjR94CLebGVWUzaJXiSQnm5f9rMD3qMEc=; h=Date:To:From:Subject:Message-Id; b=dhvk12+l6OkUE7I9cf3tvDB40lYNAKadKNEmy555AKcmY3paBziB2yhhOQGv1STNF3S9tNUeBig/rDCpnr2vgAVyoX0K4gt2dRx4peEM9TGlESAEMP343dgFGnpxCvjEXnSyAj05BeZ9CmSFI0fXUVzTxrJqfqq4Q/g526eWXt0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=shdbtR9d; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="shdbtR9d" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B6658C433C7; Sat, 30 Mar 2024 03:31:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1711769474; bh=H0Q1GoocdxkjR94CLebGVWUzaJXiSQnm5f9rMD3qMEc=; h=Date:To:From:Subject:From; b=shdbtR9dca1i8J5HdSswY+vF/kRDWxOQh3bzg9bMhZ3fTb7tMdadSF+8dOc1BDKrA Pt7NEIdRozA43LNdlvoRjHSbCUZPiJzFxJh20Lx0cD5B650xsWBW+OgrbTFWjTJAwf S1zrPN3jvP4vAK7YSKp6RYkUm49UTjPhLPYApPEc= Date: Fri, 29 Mar 2024 20:31:14 -0700 To: mm-commits@vger.kernel.org,will@kernel.org,tglx@linutronix.de,palmer@rivosinc.com,nicolas@fjasle.eu,nathan@kernel.org,mpe@ellerman.id.au,mingo@redhat.com,masahiroy@kernel.org,linux@armlinux.org.uk,hch@lst.de,git@xen0n.name,dave.hansen@linux.intel.com,corbet@lwn.net,chenhuacai@kernel.org,catalin.marinas@arm.com,bp@alien8.de,alexander.deucher@amd.com,samuel.holland@sifive.com,akpm@linux-foundation.org From: Andrew Morton Subject: + selftests-fpu-move-fp-code-to-a-separate-translation-unit.patch added to mm-nonmm-unstable branch Message-Id: <20240330033114.B6658C433C7@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The patch titled Subject: selftests/fpu: move FP code to a separate translation unit has been added to the -mm mm-nonmm-unstable branch. Its filename is selftests-fpu-move-fp-code-to-a-separate-translation-unit.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/selftests-fpu-move-fp-code-to-a-separate-translation-unit.patch This patch will later appear in the mm-nonmm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Samuel Holland Subject: selftests/fpu: move FP code to a separate translation unit Date: Fri, 29 Mar 2024 00:18:29 -0700 This ensures no compiler-generated floating-point code can appear outside kernel_fpu_{begin,end}() sections, and some architectures enforce this separation. Link: https://lkml.kernel.org/r/20240329072441.591471-15-samuel.holland@sifive.com Signed-off-by: Samuel Holland Reviewed-by: Christoph Hellwig Cc: Alex Deucher Cc: Borislav Petkov (AMD) Cc: Catalin Marinas Cc: Dave Hansen Cc: Huacai Chen Cc: Ingo Molnar Cc: Jonathan Corbet Cc: Masahiro Yamada Cc: Michael Ellerman Cc: Nathan Chancellor Cc: Nicolas Schier Cc: Palmer Dabbelt Cc: Russell King Cc: Thomas Gleixner Cc: WANG Xuerui Cc: Will Deacon Signed-off-by: Andrew Morton --- lib/Makefile | 3 - lib/test_fpu.c | 89 ------------------------------------------ lib/test_fpu.h | 8 +++ lib/test_fpu_glue.c | 59 +++++++++++++++++++++++++++ lib/test_fpu_impl.c | 37 +++++++++++++++++ 5 files changed, 106 insertions(+), 90 deletions(-) --- a/lib/Makefile~selftests-fpu-move-fp-code-to-a-separate-translation-unit +++ a/lib/Makefile @@ -133,7 +133,8 @@ FPU_CFLAGS += $(call cc-option,-msse -mp endif obj-$(CONFIG_TEST_FPU) += test_fpu.o -CFLAGS_test_fpu.o += $(FPU_CFLAGS) +test_fpu-y := test_fpu_glue.o test_fpu_impl.o +CFLAGS_test_fpu_impl.o += $(FPU_CFLAGS) # Some KUnit files (hooks.o) need to be built-in even when KUnit is a module, # so we can't just use obj-$(CONFIG_KUNIT). --- a/lib/test_fpu.c +++ /dev/null @@ -1,89 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0+ -/* - * Test cases for using floating point operations inside a kernel module. - * - * This tests kernel_fpu_begin() and kernel_fpu_end() functions, especially - * when userland has modified the floating point control registers. The kernel - * state might depend on the state set by the userland thread that was active - * before a syscall. - * - * To facilitate the test, this module registers file - * /sys/kernel/debug/selftest_helpers/test_fpu, which when read causes a - * sequence of floating point operations. If the operations fail, either the - * read returns error status or the kernel crashes. - * If the operations succeed, the read returns "1\n". - */ - -#include -#include -#include -#include - -static int test_fpu(void) -{ - /* - * This sequence of operations tests that rounding mode is - * to nearest and that denormal numbers are supported. - * Volatile variables are used to avoid compiler optimizing - * the calculations away. - */ - volatile double a, b, c, d, e, f, g; - - a = 4.0; - b = 1e-15; - c = 1e-310; - - /* Sets precision flag */ - d = a + b; - - /* Result depends on rounding mode */ - e = a + b / 2; - - /* Denormal and very large values */ - f = b / c; - - /* Depends on denormal support */ - g = a + c * f; - - if (d > a && e > a && g > a) - return 0; - else - return -EINVAL; -} - -static int test_fpu_get(void *data, u64 *val) -{ - int status = -EINVAL; - - kernel_fpu_begin(); - status = test_fpu(); - kernel_fpu_end(); - - *val = 1; - return status; -} - -DEFINE_DEBUGFS_ATTRIBUTE(test_fpu_fops, test_fpu_get, NULL, "%lld\n"); -static struct dentry *selftest_dir; - -static int __init test_fpu_init(void) -{ - selftest_dir = debugfs_create_dir("selftest_helpers", NULL); - if (!selftest_dir) - return -ENOMEM; - - debugfs_create_file_unsafe("test_fpu", 0444, selftest_dir, NULL, - &test_fpu_fops); - - return 0; -} - -static void __exit test_fpu_exit(void) -{ - debugfs_remove(selftest_dir); -} - -module_init(test_fpu_init); -module_exit(test_fpu_exit); - -MODULE_LICENSE("GPL"); --- /dev/null +++ a/lib/test_fpu_glue.c @@ -0,0 +1,59 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Test cases for using floating point operations inside a kernel module. + * + * This tests kernel_fpu_begin() and kernel_fpu_end() functions, especially + * when userland has modified the floating point control registers. The kernel + * state might depend on the state set by the userland thread that was active + * before a syscall. + * + * To facilitate the test, this module registers file + * /sys/kernel/debug/selftest_helpers/test_fpu, which when read causes a + * sequence of floating point operations. If the operations fail, either the + * read returns error status or the kernel crashes. + * If the operations succeed, the read returns "1\n". + */ + +#include +#include +#include +#include + +#include "test_fpu.h" + +static int test_fpu_get(void *data, u64 *val) +{ + int status = -EINVAL; + + kernel_fpu_begin(); + status = test_fpu(); + kernel_fpu_end(); + + *val = 1; + return status; +} + +DEFINE_DEBUGFS_ATTRIBUTE(test_fpu_fops, test_fpu_get, NULL, "%lld\n"); +static struct dentry *selftest_dir; + +static int __init test_fpu_init(void) +{ + selftest_dir = debugfs_create_dir("selftest_helpers", NULL); + if (!selftest_dir) + return -ENOMEM; + + debugfs_create_file_unsafe("test_fpu", 0444, selftest_dir, NULL, + &test_fpu_fops); + + return 0; +} + +static void __exit test_fpu_exit(void) +{ + debugfs_remove(selftest_dir); +} + +module_init(test_fpu_init); +module_exit(test_fpu_exit); + +MODULE_LICENSE("GPL"); --- /dev/null +++ a/lib/test_fpu.h @@ -0,0 +1,8 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ + +#ifndef _LIB_TEST_FPU_H +#define _LIB_TEST_FPU_H + +int test_fpu(void); + +#endif --- /dev/null +++ a/lib/test_fpu_impl.c @@ -0,0 +1,37 @@ +// SPDX-License-Identifier: GPL-2.0+ + +#include + +#include "test_fpu.h" + +int test_fpu(void) +{ + /* + * This sequence of operations tests that rounding mode is + * to nearest and that denormal numbers are supported. + * Volatile variables are used to avoid compiler optimizing + * the calculations away. + */ + volatile double a, b, c, d, e, f, g; + + a = 4.0; + b = 1e-15; + c = 1e-310; + + /* Sets precision flag */ + d = a + b; + + /* Result depends on rounding mode */ + e = a + b / 2; + + /* Denormal and very large values */ + f = b / c; + + /* Depends on denormal support */ + g = a + c * f; + + if (d > a && e > a && g > a) + return 0; + else + return -EINVAL; +} _ Patches currently in -mm which might be from samuel.holland@sifive.com are x86-fpu-fix-asm-fpu-typesh-include-guard.patch arch-add-arch_has_kernel_fpu_support.patch arm-implement-arch_has_kernel_fpu_support.patch arm-crypto-use-cc_flags_fpu-for-neon-cflags.patch arm64-implement-arch_has_kernel_fpu_support.patch arm64-crypto-use-cc_flags_fpu-for-neon-cflags.patch lib-raid6-use-cc_flags_fpu-for-neon-cflags.patch loongarch-implement-arch_has_kernel_fpu_support.patch powerpc-implement-arch_has_kernel_fpu_support.patch x86-implement-arch_has_kernel_fpu_support.patch riscv-add-support-for-kernel-mode-fpu.patch drm-amd-display-use-arch_has_kernel_fpu_support.patch selftests-fpu-move-fp-code-to-a-separate-translation-unit.patch selftests-fpu-allow-building-on-other-architectures.patch