[PATCH] x86_64: Implement is_compat_task the right way
By setting a flag during a 32bit system call only
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/arch/x86_64/ia32/ia32entry.S b/arch/x86_64/ia32/ia32entry.S
index 8172e61..58f5bfb 100644
--- a/arch/x86_64/ia32/ia32entry.S
+++ b/arch/x86_64/ia32/ia32entry.S
@@ -104,6 +104,7 @@
.quad 1b,ia32_badarg
.previous
GET_THREAD_INFO(%r10)
+ orl $TS_COMPAT,threadinfo_status(%r10)
testl $(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|_TIF_SECCOMP),threadinfo_flags(%r10)
CFI_REMEMBER_STATE
jnz sysenter_tracesys
@@ -117,6 +118,7 @@
cli
testl $_TIF_ALLWORK_MASK,threadinfo_flags(%r10)
jnz int_ret_from_sys_call
+ andl $~TS_COMPAT,threadinfo_status(%r10)
/* clear IF, that popfq doesn't enable interrupts early */
andl $~0x200,EFLAGS-R11(%rsp)
RESTORE_ARGS 1,24,1,1,1,1
@@ -203,6 +205,7 @@
.quad 1b,ia32_badarg
.previous
GET_THREAD_INFO(%r10)
+ orl $TS_COMPAT,threadinfo_status(%r10)
testl $(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|_TIF_SECCOMP),threadinfo_flags(%r10)
CFI_REMEMBER_STATE
jnz cstar_tracesys
@@ -216,6 +219,7 @@
cli
testl $_TIF_ALLWORK_MASK,threadinfo_flags(%r10)
jnz int_ret_from_sys_call
+ andl $~TS_COMPAT,threadinfo_status(%r10)
RESTORE_ARGS 1,-ARG_SKIP,1,1,1
movl RIP-ARGOFFSET(%rsp),%ecx
CFI_REGISTER rip,rcx
@@ -288,6 +292,7 @@
this could be a problem. */
SAVE_ARGS 0,0,1
GET_THREAD_INFO(%r10)
+ orl $TS_COMPAT,threadinfo_status(%r10)
testl $(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|_TIF_SECCOMP),threadinfo_flags(%r10)
jnz ia32_tracesys
ia32_do_syscall:
diff --git a/arch/x86_64/kernel/asm-offsets.c b/arch/x86_64/kernel/asm-offsets.c
index 00a08d1..cfb4f9c 100644
--- a/arch/x86_64/kernel/asm-offsets.c
+++ b/arch/x86_64/kernel/asm-offsets.c
@@ -33,6 +33,7 @@
ENTRY(flags);
ENTRY(addr_limit);
ENTRY(preempt_count);
+ ENTRY(status);
BLANK();
#undef ENTRY
#define ENTRY(entry) DEFINE(pda_ ## entry, offsetof(struct x8664_pda, entry))
diff --git a/arch/x86_64/kernel/entry.S b/arch/x86_64/kernel/entry.S
index 45e0ab8..300555b 100644
--- a/arch/x86_64/kernel/entry.S
+++ b/arch/x86_64/kernel/entry.S
@@ -313,6 +313,7 @@
movl threadinfo_flags(%rcx),%edx
andl %edi,%edx
jnz int_careful
+ andl $~TS_COMPAT,threadinfo_status(%rcx)
jmp retint_swapgs
/* Either reschedule or signal or syscall exit tracking needed. */
diff --git a/drivers/input/evdev.c b/drivers/input/evdev.c
index f7490a015..362b335 100644
--- a/drivers/input/evdev.c
+++ b/drivers/input/evdev.c
@@ -154,8 +154,10 @@
__s32 value;
};
+/* Note to the author of this code: did it ever occur to
+ you why the ifdefs are needed? Think about it again. -AK */
#ifdef CONFIG_X86_64
-# define COMPAT_TEST test_thread_flag(TIF_IA32)
+# define COMPAT_TEST is_compat_task()
#elif defined(CONFIG_IA64)
# define COMPAT_TEST IS_IA32_PROCESS(ia64_task_regs(current))
#elif defined(CONFIG_S390)
diff --git a/include/asm-x86_64/compat.h b/include/asm-x86_64/compat.h
index f0155c3..3863a7d 100644
--- a/include/asm-x86_64/compat.h
+++ b/include/asm-x86_64/compat.h
@@ -202,4 +202,9 @@
return (void __user *)regs->rsp - len;
}
+static inline int is_compat_task(void)
+{
+ return current_thread_info()->status & TS_COMPAT;
+}
+
#endif /* _ASM_X86_64_COMPAT_H */
diff --git a/include/asm-x86_64/thread_info.h b/include/asm-x86_64/thread_info.h
index 08eb6e4..eb7c5fd 100644
--- a/include/asm-x86_64/thread_info.h
+++ b/include/asm-x86_64/thread_info.h
@@ -138,6 +138,7 @@
* have to worry about atomic accesses.
*/
#define TS_USEDFPU 0x0001 /* FPU was used by this task this quantum (SMP) */
+#define TS_COMPAT 0x0002 /* 32bit syscall active */
#endif /* __KERNEL__ */