bitkeeper revision 1.1159.187.26 (41a8c480rckpADNC0Lh2VZmtPTNKeg)

We must load shared_info into %esi at every external entry point into 
entry.S (i.e., every label marked ENTRY()). I was missing at least
resume_userspace which is essential for vm86.

linux-2.6.9-xen-sparse/arch/xen/i386/kernel/entry.S

@@ -194,6 +194,7 @@ ENTRY(ret_from_fork)
 	call schedule_tail
 	GET_THREAD_INFO(%ebp)
 	popl %eax
+	movl HYPERVISOR_shared_info, %esi
 	jmp syscall_exit
 
 /*
@@ -214,6 +215,7 @@ ret_from_intr:
 	testl $(VM_MASK | 2), %eax
 	jz resume_kernel		# returning to kernel or vm86-space
 ENTRY(resume_userspace)
+	movl HYPERVISOR_shared_info, %esi
 	XEN_BLOCK_EVENTS(%esi)		# make sure we don't miss an interrupt
 					# setting need_resched or sigpending
 					# between sampling and the iret
@@ -225,6 +227,7 @@ ENTRY(resume_userspace)
 
 #ifdef CONFIG_PREEMPT
 ENTRY(resume_kernel)
+	movl HYPERVISOR_shared_info, %esi
 	cmpl $0,TI_preempt_count(%ebp)	# non-zero preempt_count ?
 	jnz restore_all
 need_resched: