linux 2.6.18: assembly annotations

This adds (or moves to the proper place) annotations paralleling those
added in native code in 2.6.18. To make this look less ugly, it
required moving around a few things.

Signed-off-by: Jan Beulich <jbeulich@novell.com>

diff --git a/linux-2.6-xen-sparse/arch/i386/kernel/entry-xen.S b/linux-2.6-xen-sparse/arch/i386/kernel/entry-xen.S
index ab569d974bf50f004e9ef5537f69d630d5c52b39..c7f38485cf1efe755c1152ea5e0b6b194f98aab0 100644 (file)
--- a/linux-2.6-xen-sparse/arch/i386/kernel/entry-xen.S
+++ b/linux-2.6-xen-sparse/arch/i386/kernel/entry-xen.S
@@ -368,6 +368,7 @@ sysexit_scrit:      /**** START OF SYSEXIT CRITICAL REGION ****/
        movl ESI(%esp), %esi
        sysexit
 14:    __DISABLE_INTERRUPTS
+       TRACE_IRQS_OFF
 sysexit_ecrit: /**** END OF SYSEXIT CRITICAL REGION ****/
        push %esp
        call evtchn_do_upcall
@@ -427,11 +428,13 @@ restore_nocheck:
 restore_nocheck:
        movl EFLAGS(%esp), %eax
        testl $(VM_MASK|NMI_MASK), %eax
+       CFI_REMEMBER_STATE
        jnz hypervisor_iret
        shr $9, %eax                    # EAX[0] == IRET_EFLAGS.IF
        GET_VCPU_INFO
        andb evtchn_upcall_mask(%esi),%al
        andb $1,%al                     # EAX[0] == IRET_EFLAGS.IF & event_mask
+       CFI_REMEMBER_STATE
        jnz restore_all_enable_events   #        != 0 => enable event delivery
 #endif
        TRACE_IRQS_IRET
@@ -455,8 +458,8 @@ iret_exc:
        .long 1b,iret_exc
 .previous
 
-#ifndef CONFIG_XEN
        CFI_RESTORE_STATE
+#ifndef CONFIG_XEN
 ldt_ss:
        larl OLDSS(%esp), %eax
        jnz restore_nocheck
@@ -485,14 +488,36 @@ ldt_ss:
        .align 4
        .long 1b,iret_exc
 .previous
-       CFI_ENDPROC
 #else
+        ALIGN
+restore_all_enable_events:
+       TRACE_IRQS_ON
+       __ENABLE_INTERRUPTS
+scrit: /**** START OF CRITICAL REGION ****/
+       __TEST_PENDING
+       jnz  14f                        # process more events if necessary...
+       RESTORE_REGS
+       addl $4, %esp
+       CFI_ADJUST_CFA_OFFSET -4
+1:     iret
+.section __ex_table,"a"
+       .align 4
+       .long 1b,iret_exc
+.previous
+14:    __DISABLE_INTERRUPTS
+       TRACE_IRQS_OFF
+       jmp  11f
+ecrit:  /**** END OF CRITICAL REGION ****/
+
+       CFI_RESTORE_STATE
 hypervisor_iret:
        andl $~NMI_MASK, EFLAGS(%esp)
        RESTORE_REGS
        addl $4, %esp
+       CFI_ADJUST_CFA_OFFSET -4
        jmp  hypercall_page + (__HYPERVISOR_iret * 32)
 #endif
+       CFI_ENDPROC
 
        # perform work that needs to be done immediately before resumption
        ALIGN
@@ -736,7 +761,9 @@ error_code:
 # critical region we know that the entire frame is present and correct
 # so we can simply throw away the new one.
 ENTRY(hypervisor_callback)
+       RING0_INT_FRAME
        pushl %eax
+       CFI_ADJUST_CFA_OFFSET 4
        SAVE_ALL
        movl EIP(%esp),%eax
        cmpl $scrit,%eax
@@ -749,26 +776,13 @@ ENTRY(hypervisor_callback)
        ja   11f
        addl $OLDESP,%esp               # Remove eflags...ebx from stack frame.
 11:    push %esp
+       CFI_ADJUST_CFA_OFFSET 4
        call evtchn_do_upcall
        add  $4,%esp
+       CFI_ADJUST_CFA_OFFSET -4
        jmp  ret_from_intr
+       CFI_ENDPROC
 
-        ALIGN
-restore_all_enable_events:
-       __ENABLE_INTERRUPTS
-scrit: /**** START OF CRITICAL REGION ****/
-       __TEST_PENDING
-       jnz  14f                        # process more events if necessary...
-       RESTORE_REGS
-       addl $4, %esp
-1:     iret
-.section __ex_table,"a"
-       .align 4
-       .long 1b,iret_exc
-.previous
-14:    __DISABLE_INTERRUPTS
-       jmp  11b
-ecrit:  /**** END OF CRITICAL REGION ****/
 # [How we do the fixup]. We want to merge the current stack frame with the
 # just-interrupted frame. How we do this depends on where in the critical
 # region the interrupted handler was executing, and so how many saved
@@ -835,6 +849,7 @@ ENTRY(failsafe_callback)
        addl $16,%esp           # EAX != 0 => Category 2 (Bad IRET)
        jmp iret_exc
 5:     addl $16,%esp           # EAX == 0 => Category 1 (Bad segment)
+       RING0_INT_FRAME
        pushl $0
        SAVE_ALL
        jmp ret_from_exception
@@ -860,6 +875,7 @@ ENTRY(failsafe_callback)
        .long 4b,9b;            \
 .previous
 #endif
+       CFI_ENDPROC
 
 ENTRY(coprocessor_error)
        RING0_INT_FRAME
@@ -1187,8 +1203,11 @@ ENDPROC(arch_unwind_init_running)
 #endif
 
 ENTRY(fixup_4gb_segment)
+       RING0_EC_FRAME
        pushl $do_fixup_4gb_segment
+       CFI_ADJUST_CFA_OFFSET 4
        jmp error_code
+       CFI_ENDPROC
 
 .section .rodata,"a"
 .align 4

diff --git a/linux-2.6-xen-sparse/arch/i386/kernel/head-xen.S b/linux-2.6-xen-sparse/arch/i386/kernel/head-xen.S
index 3d6d430ed8bdb4b23a9a5e9d29759938369c73f0..ff05486f112d1f7eed6cc199627f61ed2664d152 100644 (file)
--- a/linux-2.6-xen-sparse/arch/i386/kernel/head-xen.S
+++ b/linux-2.6-xen-sparse/arch/i386/kernel/head-xen.S
@@ -9,6 +9,7 @@
 #include <asm/cache.h>
 #include <asm/thread_info.h>
 #include <asm/asm-offsets.h>
+#include <asm/dwarf2.h>
 #include <xen/interface/xen.h>
 #include <xen/interface/elfnote.h>
 
@@ -70,7 +71,9 @@ L6:
 #define HYPERCALL_PAGE_OFFSET 0x1000
 .org HYPERCALL_PAGE_OFFSET
 ENTRY(hypercall_page)
+       CFI_STARTPROC
 .skip 0x1000
+       CFI_ENDPROC
 
 /*
  * Real beginning of normal "text" segment

diff --git a/linux-2.6-xen-sparse/arch/x86_64/kernel/entry-xen.S b/linux-2.6-xen-sparse/arch/x86_64/kernel/entry-xen.S
index cfe59a67832c2be19409a0c08fef1cc0b8061bf4..a22433f43542d9e90c5e10e8e91ecef442472824 100644 (file)
--- a/linux-2.6-xen-sparse/arch/x86_64/kernel/entry-xen.S
+++ b/linux-2.6-xen-sparse/arch/x86_64/kernel/entry-xen.S
@@ -116,19 +116,21 @@ NMI_MASK = 0x80000000
        CFI_ADJUST_CFA_OFFSET   -(6*8)
        .endm
 
-       .macro  CFI_DEFAULT_STACK start=1
+       .macro  CFI_DEFAULT_STACK start=1,adj=0
        .if \start
        CFI_STARTPROC   simple
-       CFI_DEF_CFA     rsp,SS+8
+       CFI_DEF_CFA     rsp,SS+8-(\adj*ARGOFFSET)
        .else
-       CFI_DEF_CFA_OFFSET SS+8
+       CFI_DEF_CFA_OFFSET SS+8-(\adj*ARGOFFSET)
        .endif
+       .if \adj == 0
        CFI_REL_OFFSET  r15,R15
        CFI_REL_OFFSET  r14,R14
        CFI_REL_OFFSET  r13,R13
        CFI_REL_OFFSET  r12,R12
        CFI_REL_OFFSET  rbp,RBP
        CFI_REL_OFFSET  rbx,RBX
+       .endif
        CFI_REL_OFFSET  r11,R11
        CFI_REL_OFFSET  r10,R10
        CFI_REL_OFFSET  r9,R9
@@ -363,8 +365,8 @@ ENTRY(int_ret_from_sys_call)
        CFI_REL_OFFSET  r9,R9-ARGOFFSET
        CFI_REL_OFFSET  r10,R10-ARGOFFSET
        CFI_REL_OFFSET  r11,R11-ARGOFFSET
-       TRACE_IRQS_OFF
         XEN_BLOCK_EVENTS(%rsi)
+       TRACE_IRQS_OFF
        testb $3,CS-ARGOFFSET(%rsp)
         jnz 1f
         /* Need to set the proper %ss (not NULL) for ring 3 iretq */
@@ -534,7 +536,7 @@ END(stub_rt_sigreturn)
  */ 
 
 retint_check:
-       CFI_DEFAULT_STACK
+       CFI_DEFAULT_STACK adj=1
        movl threadinfo_flags(%rcx),%edx
        andl %edi,%edx
        CFI_REMEMBER_STATE
@@ -838,6 +840,7 @@ ENTRY(error_entry)
        CFI_REL_OFFSET  r15,R15
 #if 0        
        cmpl $__KERNEL_CS,CS(%rsp)
+       CFI_REMEMBER_STATE
        je  error_kernelspace
 #endif        
 error_call_handler:
@@ -864,7 +867,7 @@ error_exit:
        TRACE_IRQS_IRETQ
        jmp   retint_restore_args
 
-error_kernelspace:
+#if 0
          /*
          * We need to re-write the logic here because we don't do iretq to 
          * to return to user mode. It's still possible that we get trap/fault
@@ -872,7 +875,8 @@ error_kernelspace:
          * for example).
          *
          */           
-#if 0
+       CFI_RESTORE_STATE
+error_kernelspace:
        incl %ebx
        /* There are two places in the kernel that can potentially fault with
           usergs. Handle them here. The exception handlers after
@@ -888,11 +892,13 @@ error_kernelspace:
        cmpq $gs_change,RIP(%rsp)
         je   error_swapgs
        jmp  error_sti
-#endif        
+#endif
+       CFI_ENDPROC
 END(error_entry)
        
 ENTRY(hypervisor_callback)
        zeroentry do_hypervisor_callback
+END(hypervisor_callback)
         
 /*
  * Copied from arch/xen/i386/kernel/entry.S
@@ -909,48 +915,66 @@ ENTRY(hypervisor_callback)
 # existing activation in its critical region -- if so, we pop the current
 # activation and restart the handler using the previous one.
 ENTRY(do_hypervisor_callback)   # do_hypervisor_callback(struct *pt_regs)
+       CFI_STARTPROC
 # Since we don't modify %rdi, evtchn_do_upall(struct *pt_regs) will
 # see the correct pointer to the pt_regs
        movq %rdi, %rsp            # we don't return, adjust the stack frame
-11:    movq %gs:pda_irqstackptr,%rax
-       incl %gs:pda_irqcount
-       cmovzq %rax,%rsp
-       pushq %rdi
+       CFI_ENDPROC
+       CFI_DEFAULT_STACK
+11:    incl %gs:pda_irqcount
+       movq %rsp,%rbp
+       CFI_DEF_CFA_REGISTER rbp
+       cmovzq %gs:pda_irqstackptr,%rsp
+       pushq %rbp                      # backlink for old unwinder
        call evtchn_do_upcall
        popq %rsp
+       CFI_DEF_CFA_REGISTER rsp
        decl %gs:pda_irqcount
        jmp  error_exit
+       CFI_ENDPROC
+END(do_hypervisor_callback)
 
 #ifdef CONFIG_X86_LOCAL_APIC
 KPROBE_ENTRY(nmi)
        zeroentry do_nmi_callback
 ENTRY(do_nmi_callback)
+       CFI_STARTPROC
         addq $8, %rsp
+       CFI_ENDPROC
+       CFI_DEFAULT_STACK
         call do_nmi
         orl  $NMI_MASK,EFLAGS(%rsp)
         RESTORE_REST
         XEN_BLOCK_EVENTS(%rsi)
+       TRACE_IRQS_OFF
         GET_THREAD_INFO(%rcx)
         jmp  retint_restore_args
+       CFI_ENDPROC
        .previous .text
+END(nmi)
 #endif
 
         ALIGN
 restore_all_enable_events:  
+       CFI_DEFAULT_STACK adj=1
+       TRACE_IRQS_ON
        XEN_UNBLOCK_EVENTS(%rsi)        # %rsi is already set up...
 
 scrit: /**** START OF CRITICAL REGION ****/
        XEN_TEST_PENDING(%rsi)
+       CFI_REMEMBER_STATE
        jnz  14f                        # process more events if necessary...
        XEN_PUT_VCPU_INFO(%rsi)
         RESTORE_ARGS 0,8,0
         HYPERVISOR_IRET 0
         
+       CFI_RESTORE_STATE
 14:    XEN_LOCKED_BLOCK_EVENTS(%rsi)
        XEN_PUT_VCPU_INFO(%rsi)
        SAVE_REST
         movq %rsp,%rdi                  # set the argument again
        jmp  11b
+       CFI_ENDPROC
 ecrit:  /**** END OF CRITICAL REGION ****/
 # At this point, unlike on x86-32, we don't do the fixup to simplify the 
 # code and the stack frame is more complex on x86-64.
@@ -970,8 +994,12 @@ ecrit:  /**** END OF CRITICAL REGION ****/
 # We distinguish between categories by comparing each saved segment register
 # with its current contents: any discrepancy means we in category 1.
 ENTRY(failsafe_callback)
+       _frame (RIP-0x30)
+       CFI_REL_OFFSET rcx, 0
+       CFI_REL_OFFSET r11, 8
        movw %ds,%cx
        cmpw %cx,0x10(%rsp)
+       CFI_REMEMBER_STATE
        jne 1f
        movw %es,%cx
        cmpw %cx,0x18(%rsp)
@@ -984,17 +1012,26 @@ ENTRY(failsafe_callback)
        jne 1f
        /* All segments match their saved values => Category 2 (Bad IRET). */
        movq (%rsp),%rcx
+       CFI_RESTORE rcx
        movq 8(%rsp),%r11
+       CFI_RESTORE r11
        addq $0x30,%rsp
+       CFI_ADJUST_CFA_OFFSET -0x30
        movq $11,%rdi   /* SIGSEGV */
        jmp do_exit                     
+       CFI_RESTORE_STATE
 1:     /* Segment mismatch => Category 1 (Bad segment). Retry the IRET. */
        movq (%rsp),%rcx
+       CFI_RESTORE rcx
        movq 8(%rsp),%r11
+       CFI_RESTORE r11
        addq $0x30,%rsp
+       CFI_ADJUST_CFA_OFFSET -0x30
        pushq $0
+       CFI_ADJUST_CFA_OFFSET 8
        SAVE_ALL
        jmp error_exit
+       CFI_ENDPROC
 #if 0        
         .section __ex_table,"a"
         .align 8
@@ -1117,12 +1154,12 @@ END(device_not_available)
 
        /* runs on exception stack */
 KPROBE_ENTRY(debug)
-       INTR_FRAME
-/*     pushq $0
+/*     INTR_FRAME
+       pushq $0
        CFI_ADJUST_CFA_OFFSET 8 */
        zeroentry do_debug
-/*     paranoid_exit */
-       CFI_ENDPROC
+/*     paranoidexit
+       CFI_ENDPROC */
 END(debug)
        .previous .text
 
@@ -1144,12 +1181,12 @@ END(nmi)
 #endif        
 
 KPROBE_ENTRY(int3)
-       INTR_FRAME
-/*     pushq $0
+/*     INTR_FRAME
+       pushq $0
        CFI_ADJUST_CFA_OFFSET 8 */
        zeroentry do_int3
-/*     jmp paranoid_exit1 */
-       CFI_ENDPROC
+/*     jmp paranoid_exit1
+       CFI_ENDPROC */
 END(int3)
        .previous .text
 
@@ -1193,9 +1230,11 @@ END(segment_not_present)
 
        /* runs on exception stack */
 ENTRY(stack_segment)
-       XCPT_FRAME
+/*     XCPT_FRAME
+       paranoidentry do_stack_segment */
        errorentry do_stack_segment
-       CFI_ENDPROC
+/*     jmp paranoid_exit1
+       CFI_ENDPROC */
 END(stack_segment)
 
 KPROBE_ENTRY(general_protection)

diff --git a/linux-2.6-xen-sparse/arch/x86_64/kernel/head-xen.S b/linux-2.6-xen-sparse/arch/x86_64/kernel/head-xen.S
index 424c1903c943eb490f1d1fa1559051089a25b20d..ca7fbf5a2bf8e31798fefc6c18fd0207745b084d 100644 (file)
--- a/linux-2.6-xen-sparse/arch/x86_64/kernel/head-xen.S
+++ b/linux-2.6-xen-sparse/arch/x86_64/kernel/head-xen.S
@@ -22,7 +22,7 @@
 #include <asm/page.h>
 #include <asm/msr.h>
 #include <asm/cache.h>
-
+#include <asm/dwarf2.h>
 #include <xen/interface/elfnote.h>
 
        .section .bootstrap.text, "ax", @progbits
@@ -40,6 +40,7 @@ ENTRY(_start)
        /* rsi is pointer to startup info structure.
           pass it to C */
        movq %rsi,%rdi
+       pushq $0                # fake return address
        jmp x86_64_start_kernel
 
 ENTRY(stext)
@@ -80,7 +81,25 @@ NEXT_PAGE(level2_kernel_pgt)
        .fill   512,8,0
 
 NEXT_PAGE(hypercall_page)
-       .fill   512,8,0
+       CFI_STARTPROC
+       .rept 0x1000 / 0x20
+       .skip 1 /* push %rcx */
+       CFI_ADJUST_CFA_OFFSET   8
+       CFI_REL_OFFSET  rcx,0
+       .skip 2 /* push %r11 */
+       CFI_ADJUST_CFA_OFFSET   8
+       CFI_REL_OFFSET  rcx,0
+       .skip 5 /* mov $#,%eax */
+       .skip 2 /* syscall */
+       .skip 2 /* pop %r11 */
+       CFI_ADJUST_CFA_OFFSET -8
+       CFI_RESTORE r11
+       .skip 1 /* pop %rcx */
+       CFI_ADJUST_CFA_OFFSET -8
+       CFI_RESTORE rcx
+       .align 0x20,0 /* ret */
+       .endr
+       CFI_ENDPROC
 
 #undef NEXT_PAGE