From: Wang Yufen <wangyu...@huawei.com>
Called getpid() When creating a new process with clone(), getpid() returns
the father_process's value. It should be child_process's value.
The reason is missing a RESET_PID in the arm clone impl.
Signed-off-by: Wang Yufen <wangyu...@huawei.com>
---
libc/sysdeps/linux/arm/clone.S | 61 ++++++++++++++++++++++++++++++---------
libc/sysdeps/linux/arm/sysdep.h | 45 ++++++++++++++++++++++++++++
2 files changed, 92 insertions(+), 14 deletions(-)
diff --git a/libc/sysdeps/linux/arm/clone.S b/libc/sysdeps/linux/arm/clone.S
index 03cd10e..29045ef 100644
--- a/libc/sysdeps/linux/arm/clone.S
+++ b/libc/sysdeps/linux/arm/clone.S
@@ -19,12 +19,17 @@
/* clone() is even more special than fork() as it mucks with stacks
and invokes a function in the right context after its all over. */
+#include <sysdep.h>
#define _ERRNO_H
#include <features.h>
#include <bits/errno.h>
#include <sys/syscall.h>
#include <bits/arm_asm.h>
#include <bits/arm_bx.h>
+#include <sysdep-cancel.h>
+
+#define CLONE_VM 0x00000100
+#define CLONE_THREAD 0x00010000
#if defined(__NR_clone)
/* int clone(int (*fn)(void *arg), void *child_stack, int flags, void *arg); */
@@ -87,6 +92,8 @@ __error:
.pool
#else
__clone:
+.fnstart
+.cantunwind
@ sanity check args
cmp r0, #0
IT(te, ne)
@@ -95,32 +102,58 @@ __clone:
beq __error
@ insert the args onto the new stack
- sub r1, r1, #8
- str r3, [r1, #4]
- @ save the function pointer as the 0th element
- str r0, [r1]
+ str r3, [r1, #-4]!
+ str r0, [r1, #-4]!
@ do the system call
@ get flags
mov r0, r2
+#ifdef RESET_PID
+ mov ip, r2
+#endif
@ new sp is already in r1
- @ load remaining arguments off the stack
- stmfd sp!, {r4}
- ldr r2, [sp, #4]
- ldr r3, [sp, #8]
- ldr r4, [sp, #12]
- DO_CALL (clone)
- movs a1, a1
- IT(t, ne)
- ldmnefd sp!, {r4}
+ push {r4, r7}
+ cfi_adjust_cfa_offset (8)
+ cfi_rel_offset (r4, 0)
+ cfi_rel_offset (r7, 4)
+ ldr r2, [sp, #8]
+ ldr r3, [sp, #12]
+ ldr r4, [sp, #16]
+ ldr r7, =SYS_ify(clone)
+ swi 0x0
+ cfi_endproc
+ cmp r0, #0
+ beq 1f
+ pop {r4, r7}
blt __error
- IT(t, ne)
#if defined(__USE_BX__)
bxne lr
#else
movne pc, lr
#endif
+ cfi_startproc
+.fnend
+PSEUDO_END (__clone)
+
+1:
+ .fnstart
+ .cantunwind
+#ifdef RESET_PID
+ tst ip, #CLONE_THREAD
+ bne 3f
+ GET_TLS (lr)
+ mov r1, r0
+ tst ip, #CLONE_VM
+ ldr r7, =SYS_ify(getpid)
+ ite ne
+ movne r0, #-1
+ swieq 0x0
+ NEGOFF_ADJ_BASE (r1, TID_OFFSET)
+ str r0, NEGOFF_OFF1 (r1, TID_OFFSET)
+ str r0, NEGOFF_OFF2 (r1, PID_OFFSET, TID_OFFSET)
+3:
+#endif
@ pick the function arg and call address off the stack and execute
ldr r0, [sp, #4]
mov lr, pc
diff --git a/libc/sysdeps/linux/arm/sysdep.h b/libc/sysdeps/linux/arm/sysdep.h
index 64f4040..38a131d 100644
--- a/libc/sysdeps/linux/arm/sysdep.h
+++ b/libc/sysdeps/linux/arm/sysdep.h
@@ -213,6 +213,51 @@ __local_syscall_error:
\
sees the right arguments.
*/
+#if __ARM_ARCH > 4 || defined (__ARM_ARCH_4T__)
+# define ARCH_HAS_BX
+#endif
+#if __ARM_ARCH > 4
+# define ARCH_HAS_BLX
+#endif
+#if __ARM_ARCH > 6 || defined (__ARM_ARCH_6K__) || defined (__ARM_ARCH_6ZK__)
+# define ARCH_HAS_HARD_TP
+#endif
+#if __ARM_ARCH > 6 || defined (__ARM_ARCH_6T2__)
+# define ARCH_HAS_T2
+#endif
+
+# ifdef __thumb2__
+# define NEGOFF_ADJ_BASE(R, OFF) add R, R, $OFF
+# define NEGOFF_ADJ_BASE2(D, S, OFF) add D, S, $OFF
+# define NEGOFF_OFF1(R, OFF) [R]
+# define NEGOFF_OFF2(R, OFFA, OFFB) [R, $((OFFA) - (OFFB))]
+# else
+# define NEGOFF_ADJ_BASE(R, OFF)
+# define NEGOFF_ADJ_BASE2(D, S, OFF) mov D, S
+# define NEGOFF_OFF1(R, OFF) [R, $OFF]
+# define NEGOFF_OFF2(R, OFFA, OFFB) [R, $OFFA]
+# endif
+
+# ifdef ARCH_HAS_HARD_TP
+/* If the cpu has cp15 available, use it. */
+# define GET_TLS(TMP) mrc p15, 0, r0, c13, c0, 3
+# else
+/* At this generic level we have no tricks to pull. Call the ABI routine. */
+# define GET_TLS(TMP) \
+ push { r1, r2, r3, lr }; \
+ cfi_remember_state; \
+ cfi_adjust_cfa_offset (16); \
+ cfi_rel_offset (r1, 0); \
+ cfi_rel_offset (r2, 4); \
+ cfi_rel_offset (r3, 8); \
+ cfi_rel_offset (lr, 12); \
+ bl __aeabi_read_tp; \
+ pop { r1, r2, r3, lr }; \
+ cfi_restore_state
+# endif /* ARCH_HAS_HARD_TP */
+
+
+
#undef DO_CALL
#if defined(__ARM_EABI__)
--
1.7.1
_______________________________________________
uClibc mailing list
uClibc@uclibc.org
http://lists.busybox.net/mailman/listinfo/uclibc
