bitkeeper revision 1.1705.1.9 (42a958fa_rGV-3MvG5pqfsVcnP31ag)

Fixup SYSCALL path correctly in xenlinux when calling into C code.
Signed-off-by: Keir Fraser <keir@xensource.com>

diff --git a/linux-2.6.11-xen-sparse/arch/xen/x86_64/kernel/entry.S b/linux-2.6.11-xen-sparse/arch/xen/x86_64/kernel/entry.S
index c0569ffc4a8755dd2fdbdc40ec114f3602f623b7..3f28d0e04efe6ef2e288969516cadf1a9ca1e80d 100644 (file)
--- a/linux-2.6.11-xen-sparse/arch/xen/x86_64/kernel/entry.S
+++ b/linux-2.6.11-xen-sparse/arch/xen/x86_64/kernel/entry.S
@@ -109,7 +109,6 @@ VGCF_IN_SYSCALL = (1<<8)
 #define preempt_stop
 #define retint_kernel retint_restore_args
 #endif 
-       
 
 /*
  * C code is not supposed to know about undefined top of stack. Every time 
@@ -118,7 +117,15 @@ VGCF_IN_SYSCALL = (1<<8)
  * RESTORE_TOP_OF_STACK syncs the syscall state after any possible ptregs
  * manipulation.
  */            
-               
+
+       /* %rsp:at FRAMEEND */ 
+       .macro FIXUP_TOP_OF_STACK tmp
+       movq    $__USER_CS,CS(%rsp)
+       movq    $-1,RCX(%rsp)
+       .endm
+
+       .macro RESTORE_TOP_OF_STACK tmp,offset=0
+       .endm
 
        .macro FAKE_STACK_FRAME child_rip
        /* push in order ss, rsp, eflags, cs, rip */
@@ -209,6 +216,7 @@ rff_action:
        je   int_ret_from_sys_call
        testl $_TIF_IA32,threadinfo_flags(%rcx)
        jnz  int_ret_from_sys_call
+       RESTORE_TOP_OF_STACK %rdi,ARGOFFSET
        jmp ret_from_sys_call
 rff_trace:
        movq %rsp,%rdi
@@ -311,6 +319,7 @@ sysret_signal:
 tracesys:                       
        SAVE_REST
        movq $-ENOSYS,RAX(%rsp)
+       FIXUP_TOP_OF_STACK %rdi
        movq %rsp,%rdi
        call syscall_trace_enter
        LOAD_ARGS ARGOFFSET  /* reload args from stack in case ptrace changed it */
@@ -323,6 +332,7 @@ tracesys:
 1:     SAVE_REST
        movq %rsp,%rdi
        call syscall_trace_leave
+       RESTORE_TOP_OF_STACK %rbx
        RESTORE_REST
        jmp ret_from_sys_call
                
@@ -421,7 +431,9 @@ ENTRY(ptregscall_common)
        CFI_ADJUST_CFA_OFFSET   -8
        SAVE_REST
        movq %r11, %r15
+       FIXUP_TOP_OF_STACK %r11
        call *%rax
+       RESTORE_TOP_OF_STACK %r11
        movq %r15, %r11
        RESTORE_REST
        pushq %r11
@@ -435,10 +447,12 @@ ENTRY(stub_execve)
        CFI_ADJUST_CFA_OFFSET   -8
        SAVE_REST
        movq %r11, %r15
+       FIXUP_TOP_OF_STACK %r11
        call sys_execve
        GET_THREAD_INFO(%rcx)
        bt $TIF_IA32,threadinfo_flags(%rcx)
        jc exec_32bit
+       RESTORE_TOP_OF_STACK %r11
        movq %r15, %r11
        RESTORE_REST
        push %r11
@@ -460,6 +474,7 @@ ENTRY(stub_rt_sigreturn)
        addq $8, %rsp           
        SAVE_REST
        movq %rsp,%rdi
+       FIXUP_TOP_OF_STACK %r11
        call sys_rt_sigreturn
        movq %rax,RAX(%rsp) # fixme, this could be done at the higher layer
        RESTORE_REST