From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 448CDC4743C for ; Wed, 23 Jun 2021 12:25:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3184061076 for ; Wed, 23 Jun 2021 12:25:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231326AbhFWM2A (ORCPT ); Wed, 23 Jun 2021 08:28:00 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:37028 "EHLO galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231529AbhFWM0x (ORCPT ); Wed, 23 Jun 2021 08:26:53 -0400 Message-Id: <20210623121456.211585137@linutronix.de> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1624451075; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: references:references; bh=xlv2+TnrhPjHRvGQbHtIyrZ0+7S9XLobYqIdUCbd4/I=; b=nirlt0RtZ6fYHirFaQcsmDTdVhuj/cN+NDAQ4SzSVWSeJ1FHKzNzIP6YmjNZbOpald8UDO k5TL4BbZX3AWFIBFKfsPoNepAxJqN8bXcrZdfrsUFBBqfadwUx8Ep+1s7DO9OR4G1ZNP98 cgoQdbJNNE1q+s9lur0BuwVwL8pk+9wNurVxqwzMjKnqxP4QbQeBdIxTfupP3MaAq2Sk2O W25/z4v12OnLNlmgAPY+sI+VSTV4WSD6KEUPHsaMwrc59PZwoaikht88nT7IKqBioIRdPK LkN8H8CgbqgKY9LWZaW50kkoImZhniP9632m1ExCTVz2go8sQOdCCKwi/KICYA== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1624451075; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: references:references; bh=xlv2+TnrhPjHRvGQbHtIyrZ0+7S9XLobYqIdUCbd4/I=; b=SOamXJxGHuR3AxuKyJVXr7t/2pHjlJJECXMXFs4BvHWJbsoN29N/vuO8POGG/HILeDAIdv fbo5ZniarrrYN+Aw== Date: Wed, 23 Jun 2021 14:02:16 +0200 From: Thomas Gleixner To: LKML Cc: Andy Lutomirski , Dave Hansen , Fenghua Yu , Tony Luck , Yu-cheng Yu , Sebastian Andrzej Siewior , Borislav Petkov , Peter Zijlstra , Kan Liang , "Chang Seok Bae" , Megha Dey , Oliver Sang Subject: [patch V4 49/65] x86/fpu: Rename xfeatures_mask_user() to xfeatures_mask_uabi() References: <20210623120127.327154589@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-transfer-encoding: 8-bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Rename it so it's clear that this is about user ABI features which can differ from the feature set which the kernel saves and restores because the kernel handles e.g. PKRU differently. But the user ABI (ptrace, signal frame) expects it to be there. Signed-off-by: Thomas Gleixner Reviewed-by: Borislav Petkov --- arch/x86/include/asm/fpu/internal.h | 7 ++++++- arch/x86/include/asm/fpu/xstate.h | 6 +++++- arch/x86/kernel/fpu/core.c | 2 +- arch/x86/kernel/fpu/signal.c | 10 +++++----- arch/x86/kernel/fpu/xstate.c | 18 +++++++++--------- 5 files changed, 26 insertions(+), 17 deletions(-) --- a/arch/x86/include/asm/fpu/internal.h +++ b/arch/x86/include/asm/fpu/internal.h @@ -324,7 +324,12 @@ static inline void os_xrstor(struct xreg */ static inline int xsave_to_user_sigframe(struct xregs_state __user *buf) { - u64 mask = xfeatures_mask_user(); + /* + * Include the features which are not xsaved/rstored by the kernel + * internally, e.g. PKRU. That's user space ABI and also required + * to allow the signal handler to modify PKRU. + */ + u64 mask = xfeatures_mask_uabi(); u32 lmask = mask; u32 hmask = mask >> 32; int err; --- a/arch/x86/include/asm/fpu/xstate.h +++ b/arch/x86/include/asm/fpu/xstate.h @@ -83,7 +83,11 @@ static inline u64 xfeatures_mask_supervi return xfeatures_mask_all & XFEATURE_MASK_SUPERVISOR_SUPPORTED; } -static inline u64 xfeatures_mask_user(void) +/* + * The xfeatures which are enabled in XCR0 and expected to be in ptrace + * buffers and signal frames. + */ +static inline u64 xfeatures_mask_uabi(void) { return xfeatures_mask_all & XFEATURE_MASK_USER_SUPPORTED; } --- a/arch/x86/kernel/fpu/core.c +++ b/arch/x86/kernel/fpu/core.c @@ -404,7 +404,7 @@ void fpu__clear_user_states(struct fpu * } /* Reset user states in registers. */ - restore_fpregs_from_init_fpstate(xfeatures_mask_user()); + restore_fpregs_from_init_fpstate(xfeatures_mask_uabi()); /* * Now all FPU registers have their desired values. Inform the FPU --- a/arch/x86/kernel/fpu/signal.c +++ b/arch/x86/kernel/fpu/signal.c @@ -257,14 +257,14 @@ static int copy_user_to_fpregs_zeroing(v if (use_xsave()) { if (fx_only) { - init_bv = xfeatures_mask_user() & ~XFEATURE_MASK_FPSSE; + init_bv = xfeatures_mask_uabi() & ~XFEATURE_MASK_FPSSE; r = fxrstor_from_user_sigframe(buf); if (!r) os_xrstor(&init_fpstate.xsave, init_bv); return r; } else { - init_bv = xfeatures_mask_user() & ~xbv; + init_bv = xfeatures_mask_uabi() & ~xbv; r = xrstor_from_user_sigframe(buf, xbv); if (!r && unlikely(init_bv)) @@ -420,7 +420,7 @@ static int __fpu__restore_sig(void __use fpregs_unlock(); if (use_xsave() && !fx_only) { - u64 init_bv = xfeatures_mask_user() & ~user_xfeatures; + u64 init_bv = xfeatures_mask_uabi() & ~user_xfeatures; ret = copy_sigframe_from_user_to_xstate(&fpu->state.xsave, buf_fx); if (ret) @@ -454,7 +454,7 @@ static int __fpu__restore_sig(void __use if (use_xsave()) { u64 init_bv; - init_bv = xfeatures_mask_user() & ~XFEATURE_MASK_FPSSE; + init_bv = xfeatures_mask_uabi() & ~XFEATURE_MASK_FPSSE; os_xrstor(&init_fpstate.xsave, init_bv); } @@ -549,7 +549,7 @@ void fpu__init_prepare_fx_sw_frame(void) fx_sw_reserved.magic1 = FP_XSTATE_MAGIC1; fx_sw_reserved.extended_size = size; - fx_sw_reserved.xfeatures = xfeatures_mask_user(); + fx_sw_reserved.xfeatures = xfeatures_mask_uabi(); fx_sw_reserved.xstate_size = fpu_user_xstate_size; if (IS_ENABLED(CONFIG_IA32_EMULATION) || --- a/arch/x86/kernel/fpu/xstate.c +++ b/arch/x86/kernel/fpu/xstate.c @@ -144,7 +144,7 @@ void fpu__init_cpu_xstate(void) * managed by XSAVE{C, OPT, S} and XRSTOR{S}. Only XSAVE user * states can be set here. */ - xsetbv(XCR_XFEATURE_ENABLED_MASK, xfeatures_mask_user()); + xsetbv(XCR_XFEATURE_ENABLED_MASK, xfeatures_mask_uabi()); /* * MSR_IA32_XSS sets supervisor states managed by XSAVES. @@ -453,7 +453,7 @@ int xfeature_size(int xfeature_nr) static int validate_user_xstate_header(const struct xstate_header *hdr) { /* No unknown or supervisor features may be set */ - if (hdr->xfeatures & ~xfeatures_mask_user()) + if (hdr->xfeatures & ~xfeatures_mask_uabi()) return -EINVAL; /* Userspace must use the uncompacted format */ @@ -756,7 +756,7 @@ void __init fpu__init_system_xstate(void cpuid_count(XSTATE_CPUID, 1, &eax, &ebx, &ecx, &edx); xfeatures_mask_all |= ecx + ((u64)edx << 32); - if ((xfeatures_mask_user() & XFEATURE_MASK_FPSSE) != XFEATURE_MASK_FPSSE) { + if ((xfeatures_mask_uabi() & XFEATURE_MASK_FPSSE) != XFEATURE_MASK_FPSSE) { /* * This indicates that something really unexpected happened * with the enumeration. Disable XSAVE and try to continue @@ -791,7 +791,7 @@ void __init fpu__init_system_xstate(void * Update info used for ptrace frames; use standard-format size and no * supervisor xstates: */ - update_regset_xstate_info(fpu_user_xstate_size, xfeatures_mask_user()); + update_regset_xstate_info(fpu_user_xstate_size, xfeatures_mask_uabi()); fpu__init_prepare_fx_sw_frame(); setup_init_fpu_buf(); @@ -828,14 +828,14 @@ void fpu__resume_cpu(void) /* * Restore XCR0 on xsave capable CPUs: */ - if (boot_cpu_has(X86_FEATURE_XSAVE)) - xsetbv(XCR_XFEATURE_ENABLED_MASK, xfeatures_mask_user()); + if (cpu_feature_enabled(X86_FEATURE_XSAVE)) + xsetbv(XCR_XFEATURE_ENABLED_MASK, xfeatures_mask_uabi()); /* * Restore IA32_XSS. The same CPUID bit enumerates support * of XSAVES and MSR_IA32_XSS. */ - if (boot_cpu_has(X86_FEATURE_XSAVES)) { + if (cpu_feature_enabled(X86_FEATURE_XSAVES)) { wrmsrl(MSR_IA32_XSS, xfeatures_mask_supervisor() | xfeatures_mask_independent()); } @@ -993,7 +993,7 @@ void copy_xstate_to_uabi_buf(struct memb break; case XSTATE_COPY_XSAVE: - header.xfeatures &= xfeatures_mask_user(); + header.xfeatures &= xfeatures_mask_uabi(); break; } @@ -1038,7 +1038,7 @@ void copy_xstate_to_uabi_buf(struct memb * compacted init_fpstate. The gap tracking will zero this * later. */ - if (!(xfeatures_mask_user() & BIT_ULL(i))) + if (!(xfeatures_mask_uabi() & BIT_ULL(i))) continue; /*