While looking in the code I discovered that
alpha has fallen behind because it doesn't use sys_getppid.
The problem is that it doesn't follow the task struct
to the task_group_leader.
The following (untested) patch should fix the problem.
Eric
---
arch/alpha/kernel/asm-offsets.c | 1 +
arch/alpha/kernel/entry.S | 16 +++++++++-------
2 files changed, 10 insertions(+), 7 deletions(-)
df0f0250c67ba8366c3c70570412b8dee08bd710
diff --git a/arch/alpha/kernel/asm-offsets.c b/arch/alpha/kernel/asm-offsets.c
index 8f2e5c7..6c56c75 100644
--- a/arch/alpha/kernel/asm-offsets.c
+++ b/arch/alpha/kernel/asm-offsets.c
@@ -28,6 +28,7 @@ void foo(void)
DEFINE(TASK_GID, offsetof(struct task_struct, gid));
DEFINE(TASK_EGID, offsetof(struct task_struct, egid));
DEFINE(TASK_REAL_PARENT, offsetof(struct task_struct, real_parent));
+ DEFINE(TASK_GROUP_LEADER, offsetof(struct task_struct, group_leader));
DEFINE(TASK_TGID, offsetof(struct task_struct, tgid));
BLANK();
diff --git a/arch/alpha/kernel/entry.S b/arch/alpha/kernel/entry.S
index e38671c..7af15bf 100644
--- a/arch/alpha/kernel/entry.S
+++ b/arch/alpha/kernel/entry.S
@@ -879,17 +879,19 @@ sys_getxpid:
/* See linux/kernel/timer.c sys_getppid for discussion
about this loop. */
- ldq $3, TASK_REAL_PARENT($2)
-1: ldl $1, TASK_TGID($3)
+ ldq $3, TASK_GROUP_LEADER($2)
+ ldq $4, TASK_REAL_PARENT($3)
+ ldl $0, TASK_TGID($2)
+1: ldl $1, TASK_TGID($4)
#ifdef CONFIG_SMP
- mov $3, $4
+ mov $4, $5
mb
- ldq $3, TASK_REAL_PARENT($2)
- cmpeq $3, $4, $4
- beq $4, 1b
+ ldq $3, TASK_GROUP_LEADER($2)
+ ldq $4, TASK_REAL_PARENT($3)
+ cmpeq $4, $5, $5
+ beq $5, 1b
#endif
stq $1, 80($sp)
- ldl $0, TASK_TGID($2)
ret
.end sys_getxpid
--
1.1.3.g5c7d
On Wed, Jan 25, 2006 at 12:05:58PM -0700, Eric W. Biederman wrote:
> The following (untested) patch should fix the problem.
Looks good; well spotted.
r~