x86: get rid of the insane TIF_ABI_PENDING bit

commit 05d43ed8a89c159ff641d472f970e3f1baa66318 upstream.

Now that the previous commit made it possible to do the personality
setting at the point of no return, we do just that for ELF binaries.
And suddenly all the reasons for that insane TIF_ABI_PENDING bit go
away, and we can just make SET_PERSONALITY() just do the obvious thing
for a 32-bit compat process.

Everything becomes much more straightforward this way.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/arch/x86/ia32/ia32_aout.c b/arch/x86/ia32/ia32_aout.c
index 435d2a5323daf466b208b00ff22955f09873ebe7..f9f472462753c1dd41f1a4a3087769dfdc0af6ec 100644 (file)
--- a/arch/x86/ia32/ia32_aout.c
+++ b/arch/x86/ia32/ia32_aout.c
@@ -311,7 +311,6 @@ static int load_aout_binary(struct linux_binprm *bprm, struct pt_regs *regs)
        /* OK, This is the point of no return */
        set_personality(PER_LINUX);
        set_thread_flag(TIF_IA32);
-       clear_thread_flag(TIF_ABI_PENDING);
 
        setup_new_exec(bprm);
 

diff --git a/arch/x86/include/asm/elf.h b/arch/x86/include/asm/elf.h
index 456a304b817266320ad59d6f6b49419ea4e1aa15..8ac9d9ae129e787d99979472880c1ba53f2fd830 100644 (file)
--- a/arch/x86/include/asm/elf.h
+++ b/arch/x86/include/asm/elf.h
@@ -197,14 +197,8 @@ do {                                                       \
        set_fs(USER_DS);                                \
 } while (0)
 
-#define COMPAT_SET_PERSONALITY(ex)                     \
-do {                                                   \
-       if (test_thread_flag(TIF_IA32))                 \
-               clear_thread_flag(TIF_ABI_PENDING);     \
-       else                                            \
-               set_thread_flag(TIF_ABI_PENDING);       \
-       current->personality |= force_personality32;    \
-} while (0)
+void set_personality_ia32(void);
+#define COMPAT_SET_PERSONALITY(ex) set_personality_ia32()
 
 #define COMPAT_ELF_PLATFORM                    ("i686")
 

diff --git a/arch/x86/include/asm/thread_info.h b/arch/x86/include/asm/thread_info.h
index d27d0a2fec4c227540fe4042ea823853fd82a8d3..19c3ce4aaea7eac490082d8545be7dadcbaac45f 100644 (file)
--- a/arch/x86/include/asm/thread_info.h
+++ b/arch/x86/include/asm/thread_info.h
@@ -86,7 +86,6 @@ struct thread_info {
 #define TIF_NOTSC              16      /* TSC is not accessible in userland */
 #define TIF_IA32               17      /* 32bit process */
 #define TIF_FORK               18      /* ret_from_fork */
-#define TIF_ABI_PENDING                19
 #define TIF_MEMDIE             20
 #define TIF_DEBUG              21      /* uses debug registers */
 #define TIF_IO_BITMAP          22      /* uses I/O bitmap */
@@ -110,7 +109,6 @@ struct thread_info {
 #define _TIF_NOTSC             (1 << TIF_NOTSC)
 #define _TIF_IA32              (1 << TIF_IA32)
 #define _TIF_FORK              (1 << TIF_FORK)
-#define _TIF_ABI_PENDING       (1 << TIF_ABI_PENDING)
 #define _TIF_DEBUG             (1 << TIF_DEBUG)
 #define _TIF_IO_BITMAP         (1 << TIF_IO_BITMAP)
 #define _TIF_FREEZE            (1 << TIF_FREEZE)

diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index 5284cd2b57769f53e79f520ecc6f8199720497cf..f010ab424f1f9ccc03b3f8ed7b4e759609ef733a 100644 (file)
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -91,18 +91,6 @@ void flush_thread(void)
 {
        struct task_struct *tsk = current;
 
-#ifdef CONFIG_X86_64
-       if (test_tsk_thread_flag(tsk, TIF_ABI_PENDING)) {
-               clear_tsk_thread_flag(tsk, TIF_ABI_PENDING);
-               if (test_tsk_thread_flag(tsk, TIF_IA32)) {
-                       clear_tsk_thread_flag(tsk, TIF_IA32);
-               } else {
-                       set_tsk_thread_flag(tsk, TIF_IA32);
-                       current_thread_info()->status |= TS_COMPAT;
-               }
-       }
-#endif
-
        clear_tsk_thread_flag(tsk, TIF_DEBUG);
 
        tsk->thread.debugreg0 = 0;

diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index eb62cbcaa490ad553ef5d70b6751a2288d25089e..f9ce04f610038ca14d91efbedb3a1055b0ac3129 100644 (file)
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -540,6 +540,17 @@ sys_clone(unsigned long clone_flags, unsigned long newsp,
        return do_fork(clone_flags, newsp, regs, 0, parent_tid, child_tid);
 }
 
+void set_personality_ia32(void)
+{
+       /* inherit personality from parent */
+
+       /* Make sure to be in 32bit mode */
+       set_thread_flag(TIF_IA32);
+
+       /* Prepare the first "return" to user space */
+       current_thread_info()->status |= TS_COMPAT;
+}
+
 unsigned long get_wchan(struct task_struct *p)
 {
        unsigned long stack;