# HG changeset patch
# User awilliam@xxxxxxxxxxx
# Node ID 8254ba7c0defcebb9b439a91468b6cfae89b5dc2
# Parent 357a3c90d67bad40b0bd511eea117db250486c5d
[IA64] fix paravirtualization of clone2() system call.
If audit is enabled or the child process is ptraced,
non-paravirtualized code path is executed.
Thus paravirtualized ifs is left unmodifed so that the child process
crashes after clone2().
paravirtualize ia64_ret_from_clone() to fix it.
Signed-off-by: Isaku Yamahata <yamahata@xxxxxxxxxxxxx>
---
linux-2.6-xen-sparse/arch/ia64/kernel/entry.S | 4 +-
linux-2.6-xen-sparse/arch/ia64/xen/xenentry.S | 41 +++++++++++++++++++++
linux-2.6-xen-sparse/include/asm-ia64/privop.h | 1
linux-2.6-xen-sparse/include/asm-ia64/xen/privop.h | 1
4 files changed, 45 insertions(+), 2 deletions(-)
diff -r 357a3c90d67b -r 8254ba7c0def
linux-2.6-xen-sparse/arch/ia64/kernel/entry.S
--- a/linux-2.6-xen-sparse/arch/ia64/kernel/entry.S Wed Nov 22 09:30:27
2006 -0700
+++ b/linux-2.6-xen-sparse/arch/ia64/kernel/entry.S Wed Nov 22 10:10:38
2006 -0700
@@ -602,7 +602,7 @@ GLOBAL_ENTRY(ia64_strace_leave_kernel)
.ret4: br.cond.sptk ia64_leave_kernel
END(ia64_strace_leave_kernel)
-GLOBAL_ENTRY(ia64_ret_from_clone)
+GLOBAL_ENTRY(__ia64_ret_from_clone)
PT_REGS_UNWIND_INFO(0)
{ /*
* Some versions of gas generate bad unwind info if the first
instruction of a
@@ -628,7 +628,7 @@ GLOBAL_ENTRY(ia64_ret_from_clone)
cmp.ne p6,p0=r2,r0
(p6) br.cond.spnt .strace_check_retval
;; // added stop bits to prevent
r8 dependency
-END(ia64_ret_from_clone)
+END(__ia64_ret_from_clone)
// fall through
GLOBAL_ENTRY(ia64_ret_from_syscall)
PT_REGS_UNWIND_INFO(0)
diff -r 357a3c90d67b -r 8254ba7c0def
linux-2.6-xen-sparse/arch/ia64/xen/xenentry.S
--- a/linux-2.6-xen-sparse/arch/ia64/xen/xenentry.S Wed Nov 22 09:30:27
2006 -0700
+++ b/linux-2.6-xen-sparse/arch/ia64/xen/xenentry.S Wed Nov 22 10:10:38
2006 -0700
@@ -237,6 +237,47 @@ END(ia64_trace_syscall)
END(ia64_trace_syscall)
#endif
+#ifdef CONFIG_XEN
+GLOBAL_ENTRY(xen_ret_from_clone)
+ PT_REGS_UNWIND_INFO(0)
+ movl r16=running_on_xen;;
+ ld4 r16=[r16];;
+ cmp.eq p7,p0=r16,r0
+(p7) br.cond.sptk.many __ia64_ret_from_clone;;
+#else
+GLOBAL_ENTRY(ia64_ret_from_clone)
+ PT_REGS_UNWIND_INFO(0)
+#endif
+{ /*
+ * Some versions of gas generate bad unwind info if the first
instruction of a
+ * procedure doesn't go into the first slot of a bundle. This is a
workaround.
+ */
+ nop.m 0
+ nop.i 0
+ /*
+ * We need to call schedule_tail() to complete the scheduling process.
+ * Called by ia64_switch_to() after do_fork()->copy_thread(). r8
contains the
+ * address of the previously executing task.
+ */
+ br.call.sptk.many rp=ia64_invoke_schedule_tail
+}
+.ret8:
+ adds r2=TI_FLAGS+IA64_TASK_SIZE,r13
+ ;;
+ ld4 r2=[r2]
+ ;;
+ mov r8=0
+ and r2=_TIF_SYSCALL_TRACEAUDIT,r2
+ ;;
+ cmp.ne p6,p0=r2,r0
+(p6) br.cond.spnt .strace_check_retval
+ ;; // added stop bits to prevent
r8 dependency
+#ifdef CONFIG_XEN
+ br.cond.sptk ia64_ret_from_syscall
+END(xen_ret_from_clone)
+#else
+END(ia64_ret_from_clone)
+#endif
/*
* ia64_leave_syscall(): Same as ia64_leave_kernel, except that it doesn't
* need to switch to bank 0 and doesn't restore the scratch registers.
diff -r 357a3c90d67b -r 8254ba7c0def
linux-2.6-xen-sparse/include/asm-ia64/privop.h
--- a/linux-2.6-xen-sparse/include/asm-ia64/privop.h Wed Nov 22 09:30:27
2006 -0700
+++ b/linux-2.6-xen-sparse/include/asm-ia64/privop.h Wed Nov 22 10:10:38
2006 -0700
@@ -49,6 +49,7 @@
#define ia64_leave_kernel __ia64_leave_kernel
#define ia64_leave_syscall __ia64_leave_syscall
#define ia64_trace_syscall __ia64_trace_syscall
+#define ia64_ret_from_clone __ia64_ret_from_clone
#define ia64_switch_to __ia64_switch_to
#define ia64_pal_call_static __ia64_pal_call_static
diff -r 357a3c90d67b -r 8254ba7c0def
linux-2.6-xen-sparse/include/asm-ia64/xen/privop.h
--- a/linux-2.6-xen-sparse/include/asm-ia64/xen/privop.h Wed Nov 22
09:30:27 2006 -0700
+++ b/linux-2.6-xen-sparse/include/asm-ia64/xen/privop.h Wed Nov 22
10:10:38 2006 -0700
@@ -295,6 +295,7 @@ extern void xen_ptcga(unsigned long addr
#define ia64_leave_kernel xen_leave_kernel
#define ia64_leave_syscall xen_leave_syscall
#define ia64_trace_syscall xen_trace_syscall
+#define ia64_ret_from_clone xen_ret_from_clone
#define ia64_switch_to xen_switch_to
#define ia64_pal_call_static xen_pal_call_static
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