Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755160AbbGTBLE (ORCPT ); Sun, 19 Jul 2015 21:11:04 -0400 Received: from mail-yk0-f178.google.com ([209.85.160.178]:34275 "EHLO mail-yk0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754094AbbGTBJR (ORCPT ); Sun, 19 Jul 2015 21:09:17 -0400 From: Brian Gerst To: x86@kernel.org, linux-kernel@vger.kernel.org Cc: Ingo Molnar , "H. Peter Anvin" , Denys Vlasenko , Andy Lutomirski , Linus Torvalds Subject: [PATCH 1/7] x86/vm86: Clean up saved_fs/gs Date: Sun, 19 Jul 2015 21:09:04 -0400 Message-Id: <1437354550-25858-2-git-send-email-brgerst@gmail.com> X-Mailer: git-send-email 2.4.3 In-Reply-To: <1437354550-25858-1-git-send-email-brgerst@gmail.com> References: <1437354550-25858-1-git-send-email-brgerst@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1891 Lines: 55 There is no need to save FS and non-lazy GS outside the 32-bit regs. Lazy GS still needs to be saved because it wasn't saved on syscall entry. Save it in the gs slot of regs32, which is present but unused. Signed-off-by: Brian Gerst --- arch/x86/include/asm/processor.h | 2 -- arch/x86/kernel/vm86_32.c | 6 ++---- 2 files changed, 2 insertions(+), 6 deletions(-) diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index 43e6519..f4e4e3f 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -410,8 +410,6 @@ struct thread_struct { unsigned long v86flags; unsigned long v86mask; unsigned long saved_sp0; - unsigned int saved_fs; - unsigned int saved_gs; #endif /* IO permissions: */ unsigned long *io_bitmap_ptr; diff --git a/arch/x86/kernel/vm86_32.c b/arch/x86/kernel/vm86_32.c index fc9db6e..761a2f9 100644 --- a/arch/x86/kernel/vm86_32.c +++ b/arch/x86/kernel/vm86_32.c @@ -159,8 +159,7 @@ struct pt_regs *save_v86_state(struct kernel_vm86_regs *regs) ret = KVM86->regs32; - ret->fs = current->thread.saved_fs; - set_user_gs(ret, current->thread.saved_gs); + lazy_load_gs(ret->gs); return ret; } @@ -315,8 +314,7 @@ static void do_sys_vm86(struct kernel_vm86_struct *info, struct task_struct *tsk */ info->regs32->ax = VM86_SIGNAL; tsk->thread.saved_sp0 = tsk->thread.sp0; - tsk->thread.saved_fs = info->regs32->fs; - tsk->thread.saved_gs = get_user_gs(info->regs32); + lazy_save_gs(info->regs32->gs); tss = &per_cpu(cpu_tss, get_cpu()); tsk->thread.sp0 = (unsigned long) &info->VM86_TSS_ESP0; -- 2.4.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/