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x86: mark associated mm when running a task in 32 bit compatibility mode

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This patch simply follows the same practice as for setting the TIF_IA32 flag.
In particular, an mm is marked as holding 32-bit tasks when a 32-bit binary is
exec'ed.  Both ELF and a.out formats are updated.

Signed-off-by: Stephen Wilson <wilsons@start.ca>
Reviewed-by: Michel Lespinasse <walken@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Stephen Wilson 2011-03-13 15:49:14 -04:00 committed by Al Viro
parent c2ef45df3b
commit 375906f876
2 changed files with 9 additions and 0 deletions
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1
arch/x86/ia32/ia32_aout.c
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@ -298,6 +298,7 @@ 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);
current->mm->context.ia32_compat = 1;
setup_new_exec(bprm);

8
arch/x86/kernel/process_64.c
View file

@ -501,6 +501,10 @@ void set_personality_64bit(void)
/* Make sure to be in 64bit mode */
clear_thread_flag(TIF_IA32);
/* Ensure the corresponding mm is not marked. */
if (current->mm)
current->mm->context.ia32_compat = 0;
/* TBD: overwrites user setup. Should have two bits.
But 64bit processes have always behaved this way,
so it's not too bad. The main problem is just that
@ -516,6 +520,10 @@ void set_personality_ia32(void)
set_thread_flag(TIF_IA32);
current->personality |= force_personality32;
/* Mark the associated mm as containing 32-bit tasks. */
if (current->mm)
current->mm->context.ia32_compat = 1;
/* Prepare the first "return" to user space */
current_thread_info()->status |= TS_COMPAT;
}