[PATCH] uml: x86_64 ptrace fixes
This patch fixes some missing ptrace bits on x86_64. PTRACE_ARCH_PRCTL is
hooked up and implemented. This required generalizing arch_prctl_skas
slightly to take a task_struct to modify. Previously, it always operated on
current.
Reading and writing the debug registers is also enabled by un-ifdefing the
code that implements that. It turns out that x86_64 is identical to i386, so
the same code can be used.
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/um/sys-x86_64/syscalls.c b/arch/um/sys-x86_64/syscalls.c
index f309fa9..01b91f9 100644
--- a/arch/um/sys-x86_64/syscalls.c
+++ b/arch/um/sys-x86_64/syscalls.c
@@ -59,18 +59,20 @@
#ifdef CONFIG_MODE_SKAS
-static long arch_prctl_skas(int code, unsigned long __user *addr)
+long arch_prctl_skas(struct task_struct *task, int code,
+ unsigned long __user *addr)
{
unsigned long *ptr = addr, tmp;
long ret;
- int pid = current->mm->context.skas.id.u.pid;
+ int pid = task->mm->context.skas.id.u.pid;
/*
* With ARCH_SET_FS (and ARCH_SET_GS is treated similarly to
* be safe), we need to call arch_prctl on the host because
* setting %fs may result in something else happening (like a
- * GDT being set instead). So, we let the host fiddle the
- * registers and restore them afterwards.
+ * GDT or thread.fs being set instead). So, we let the host
+ * fiddle the registers and thread struct and restore the
+ * registers afterwards.
*
* So, the saved registers are stored to the process (this
* needed because a stub may have been the last thing to run),
@@ -118,7 +120,7 @@
long sys_arch_prctl(int code, unsigned long addr)
{
- return CHOOSE_MODE_PROC(arch_prctl_tt, arch_prctl_skas, code,
+ return CHOOSE_MODE_PROC(arch_prctl_tt, arch_prctl_skas, current, code,
(unsigned long __user *) addr);
}
@@ -141,6 +143,6 @@
if(to->thread.arch.fs == 0)
return;
- arch_prctl_skas(ARCH_SET_FS, (void __user *) to->thread.arch.fs);
+ arch_prctl_skas(to, ARCH_SET_FS, (void __user *) to->thread.arch.fs);
}