From mboxrd@z Thu Jan 1 00:00:00 1970 From: "H. Peter Anvin" Subject: [PATCH 15/30] x32: Add a thread flag for x32 processes Date: Sun, 19 Feb 2012 16:07:53 -0800 Message-ID: <1329696488-16970-16-git-send-email-hpa@zytor.com> References: <1329696488-16970-1-git-send-email-hpa@zytor.com> Return-path: Received: from terminus.zytor.com ([198.137.202.10]:57267 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752533Ab2BTAPq (ORCPT ); Sun, 19 Feb 2012 19:15:46 -0500 In-Reply-To: <1329696488-16970-1-git-send-email-hpa@zytor.com> Sender: linux-arch-owner@vger.kernel.org List-ID: To: linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org Cc: mingo@kernel.org, tglx@linutronix.de, hpa@zytor.com, torvalds@linux-foundation.org, akpm@linux-foundation.org, hjl.tools@gmail.com From: "H. Peter Anvin" An x32 process is *almost* the same thing as a 64-bit process with a 32-bit address limit, but there are a few minor differences -- in particular core dumps are 32 bits and signal handling is different. Signed-off-by: H. Peter Anvin --- arch/x86/include/asm/thread_info.h | 2 ++ arch/x86/kernel/process_64.c | 2 ++ 2 files changed, 4 insertions(+), 0 deletions(-) diff --git a/arch/x86/include/asm/thread_info.h b/arch/x86/include/asm/thread_info.h index d1803a4..912e935 100644 --- a/arch/x86/include/asm/thread_info.h +++ b/arch/x86/include/asm/thread_info.h @@ -96,6 +96,7 @@ struct thread_info { #define TIF_LAZY_MMU_UPDATES 27 /* task is updating the mmu lazily */ #define TIF_SYSCALL_TRACEPOINT 28 /* syscall tracepoint instrumentation */ #define TIF_ADDR32 29 /* 32-bit address space on 64 bits */ +#define TIF_X32 30 /* 32-bit native x86-64 binary */ #define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE) #define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME) @@ -118,6 +119,7 @@ struct thread_info { #define _TIF_LAZY_MMU_UPDATES (1 << TIF_LAZY_MMU_UPDATES) #define _TIF_SYSCALL_TRACEPOINT (1 << TIF_SYSCALL_TRACEPOINT) #define _TIF_ADDR32 (1 << TIF_ADDR32) +#define _TIF_X32 (1 << TIF_X32) /* work to do in syscall_trace_enter() */ #define _TIF_WORK_SYSCALL_ENTRY \ diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c index 0e900d0..5fe2fba 100644 --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -509,6 +509,7 @@ void set_personality_64bit(void) /* Make sure to be in 64bit mode */ clear_thread_flag(TIF_IA32); clear_thread_flag(TIF_ADDR32); + clear_thread_flag(TIF_X32); /* Ensure the corresponding mm is not marked. */ if (current->mm) @@ -528,6 +529,7 @@ void set_personality_ia32(void) /* Make sure to be in 32bit mode */ set_thread_flag(TIF_IA32); set_thread_flag(TIF_ADDR32); + clear_thread_flag(TIF_X32); current->personality |= force_personality32; /* Mark the associated mm as containing 32-bit tasks. */ -- 1.7.6.5