3 files changed, 149 insertions, 56 deletions

diff --git a/arch/sh/kernel/cpu/sh3/entry.S b/arch/sh/kernel/cpu/sh3/entry.S
index 3f7e2a22c7c2..f6a389c996cb 100644
--- a/arch/sh/kernel/cpu/sh3/entry.S
+++ b/arch/sh/kernel/cpu/sh3/entry.S
@@ -132,7 +132,6 @@ ENTRY(tlb_protection_violation_store)
          mov    #1, r5
 
 call_handle_tlbmiss:
-        setup_frame_reg
         mov.l   1f, r0
         mov     r5, r8
         mov.l   @r0, r6
@@ -365,6 +364,8 @@ handle_exception:
          mov.l  @k2, k2         ! read out vector and keep in k2
 
 handle_exception_special:
+        setup_frame_reg
+
         ! Setup return address and jump to exception handler
         mov.l   7f, r9          ! fetch return address
         stc     r2_bank, r0     ! k2 (vector)
diff --git a/arch/sh/kernel/dwarf.c b/arch/sh/kernel/dwarf.c
index 88d28ec3780a..bd1c497280a6 100644
--- a/arch/sh/kernel/dwarf.c
+++ b/arch/sh/kernel/dwarf.c
@@ -39,10 +39,10 @@ static mempool_t *dwarf_frame_pool;
 static struct kmem_cache *dwarf_reg_cachep;
 static mempool_t *dwarf_reg_pool;
 
-static LIST_HEAD(dwarf_cie_list);
+static struct rb_root cie_root;
 static DEFINE_SPINLOCK(dwarf_cie_lock);
 
-static LIST_HEAD(dwarf_fde_list);
+static struct rb_root fde_root;
 static DEFINE_SPINLOCK(dwarf_fde_lock);
 
 static struct dwarf_cie *cached_cie;
@@ -301,7 +301,8 @@ static inline int dwarf_entry_len(char *addr, unsigned long *len)
  */
 static struct dwarf_cie *dwarf_lookup_cie(unsigned long cie_ptr)
 {
-        struct dwarf_cie *cie;
+        struct rb_node **rb_node = &cie_root.rb_node;
+        struct dwarf_cie *cie = NULL;
         unsigned long flags;
 
         spin_lock_irqsave(&dwarf_cie_lock, flags);
@@ -315,16 +316,24 @@ static struct dwarf_cie *dwarf_lookup_cie(unsigned long cie_ptr)
                 goto out;
         }
 
-        list_for_each_entry(cie, &dwarf_cie_list, link) {
-                if (cie->cie_pointer == cie_ptr) {
-                        cached_cie = cie;
-                        break;
+        while (*rb_node) {
+                struct dwarf_cie *cie_tmp;
+
+                cie_tmp = rb_entry(*rb_node, struct dwarf_cie, node);
+                BUG_ON(!cie_tmp);
+
+                if (cie_ptr == cie_tmp->cie_pointer) {
+                        cie = cie_tmp;
+                        cached_cie = cie_tmp;
+                        goto out;
+                } else {
+                        if (cie_ptr < cie_tmp->cie_pointer)
+                                rb_node = &(*rb_node)->rb_left;
+                        else
+                                rb_node = &(*rb_node)->rb_right;
                 }
         }
 
-        /* Couldn't find the entry in the list. */
-        if (&cie->link == &dwarf_cie_list)
-                cie = NULL;
 out:
         spin_unlock_irqrestore(&dwarf_cie_lock, flags);
         return cie;
@@ -336,25 +345,34 @@ out:
  */
 struct dwarf_fde *dwarf_lookup_fde(unsigned long pc)
 {
-        struct dwarf_fde *fde;
+        struct rb_node **rb_node = &fde_root.rb_node;
+        struct dwarf_fde *fde = NULL;
         unsigned long flags;
 
         spin_lock_irqsave(&dwarf_fde_lock, flags);
 
-        list_for_each_entry(fde, &dwarf_fde_list, link) {
-                unsigned long start, end;
+        while (*rb_node) {
+                struct dwarf_fde *fde_tmp;
+                unsigned long tmp_start, tmp_end;
 
-                start = fde->initial_location;
-                end = fde->initial_location + fde->address_range;
+                fde_tmp = rb_entry(*rb_node, struct dwarf_fde, node);
+                BUG_ON(!fde_tmp);
 
-                if (pc >= start && pc < end)
-                        break;
-        }
+                tmp_start = fde_tmp->initial_location;
+                tmp_end = fde_tmp->initial_location + fde_tmp->address_range;
 
-        /* Couldn't find the entry in the list. */
-        if (&fde->link == &dwarf_fde_list)
-                fde = NULL;
+                if (pc < tmp_start) {
+                        rb_node = &(*rb_node)->rb_left;
+                } else {
+                        if (pc < tmp_end) {
+                                fde = fde_tmp;
+                                goto out;
+                        } else
+                                rb_node = &(*rb_node)->rb_right;
+                }
+        }
 
+out:
         spin_unlock_irqrestore(&dwarf_fde_lock, flags);
 
         return fde;
@@ -540,6 +558,8 @@ void dwarf_free_frame(struct dwarf_frame *frame)
         mempool_free(frame, dwarf_frame_pool);
 }
 
+extern void ret_from_irq(void);
+
 /**
  *      dwarf_unwind_stack - unwind the stack
  *
@@ -550,8 +570,8 @@ void dwarf_free_frame(struct dwarf_frame *frame)
  *      on the callstack. Each of the lower (older) stack frames are
  *      linked via the "prev" member.
  */
-struct dwarf_frame * dwarf_unwind_stack(unsigned long pc,
-                                        struct dwarf_frame *prev)
+struct dwarf_frame *dwarf_unwind_stack(unsigned long pc,
+                                       struct dwarf_frame *prev)
 {
         struct dwarf_frame *frame;
         struct dwarf_cie *cie;
@@ -678,6 +698,24 @@ struct dwarf_frame * dwarf_unwind_stack(unsigned long pc,
         addr = frame->cfa + reg->addr;
         frame->return_addr = __raw_readl(addr);
 
+        /*
+         * Ah, the joys of unwinding through interrupts.
+         *
+         * Interrupts are tricky - the DWARF info needs to be _really_
+         * accurate and unfortunately I'm seeing a lot of bogus DWARF
+         * info. For example, I've seen interrupts occur in epilogues
+         * just after the frame pointer (r14) had been restored. The
+         * problem was that the DWARF info claimed that the CFA could be
+         * reached by using the value of the frame pointer before it was
+         * restored.
+         *
+         * So until the compiler can be trusted to produce reliable
+         * DWARF info when it really matters, let's stop unwinding once
+         * we've calculated the function that was interrupted.
+         */
+        if (prev && prev->pc == (unsigned long)ret_from_irq)
+                frame->return_addr = 0;
+
         return frame;
 
 bail:
@@ -688,6 +726,8 @@ bail:
 static int dwarf_parse_cie(void *entry, void *p, unsigned long len,
                            unsigned char *end, struct module *mod)
 {
+        struct rb_node **rb_node = &cie_root.rb_node;
+        struct rb_node *parent;
         struct dwarf_cie *cie;
         unsigned long flags;
         int count;
@@ -782,11 +822,30 @@ static int dwarf_parse_cie(void *entry, void *p, unsigned long len,
         cie->initial_instructions = p;
         cie->instructions_end = end;
 
-        cie->mod = mod;
-
         /* Add to list */
         spin_lock_irqsave(&dwarf_cie_lock, flags);
-        list_add_tail(&cie->link, &dwarf_cie_list);
+
+        while (*rb_node) {
+                struct dwarf_cie *cie_tmp;
+
+                cie_tmp = rb_entry(*rb_node, struct dwarf_cie, node);
+
+                parent = *rb_node;
+
+                if (cie->cie_pointer < cie_tmp->cie_pointer)
+                        rb_node = &parent->rb_left;
+                else if (cie->cie_pointer >= cie_tmp->cie_pointer)
+                        rb_node = &parent->rb_right;
+                else
+                        WARN_ON(1);
+        }
+
+        rb_link_node(&cie->node, parent, rb_node);
+        rb_insert_color(&cie->node, &cie_root);
+
+        if (mod != NULL)
+                list_add_tail(&cie->link, &mod->arch.cie_list);
+
         spin_unlock_irqrestore(&dwarf_cie_lock, flags);
 
         return 0;
@@ -796,6 +855,8 @@ static int dwarf_parse_fde(void *entry, u32 entry_type,
                            void *start, unsigned long len,
                            unsigned char *end, struct module *mod)
 {
+        struct rb_node **rb_node = &fde_root.rb_node;
+        struct rb_node *parent;
         struct dwarf_fde *fde;
         struct dwarf_cie *cie;
         unsigned long flags;
@@ -843,11 +904,38 @@ static int dwarf_parse_fde(void *entry, u32 entry_type,
         fde->instructions = p;
         fde->end = end;
 
-        fde->mod = mod;
-
         /* Add to list. */
         spin_lock_irqsave(&dwarf_fde_lock, flags);
-        list_add_tail(&fde->link, &dwarf_fde_list);
+
+        while (*rb_node) {
+                struct dwarf_fde *fde_tmp;
+                unsigned long tmp_start, tmp_end;
+                unsigned long start, end;
+
+                fde_tmp = rb_entry(*rb_node, struct dwarf_fde, node);
+
+                start = fde->initial_location;
+                end = fde->initial_location + fde->address_range;
+
+                tmp_start = fde_tmp->initial_location;
+                tmp_end = fde_tmp->initial_location + fde_tmp->address_range;
+
+                parent = *rb_node;
+
+                if (start < tmp_start)
+                        rb_node = &parent->rb_left;
+                else if (start >= tmp_end)
+                        rb_node = &parent->rb_right;
+                else
+                        WARN_ON(1);
+        }
+
+        rb_link_node(&fde->node, parent, rb_node);
+        rb_insert_color(&fde->node, &fde_root);
+
+        if (mod != NULL)
+                list_add_tail(&fde->link, &mod->arch.fde_list);
+
         spin_unlock_irqrestore(&dwarf_fde_lock, flags);
 
         return 0;
@@ -892,19 +980,29 @@ static struct unwinder dwarf_unwinder = {
 
 static void dwarf_unwinder_cleanup(void)
 {
-        struct dwarf_cie *cie, *cie_tmp;
-        struct dwarf_fde *fde, *fde_tmp;
+        struct rb_node **fde_rb_node = &fde_root.rb_node;
+        struct rb_node **cie_rb_node = &cie_root.rb_node;
 
         /*
          * Deallocate all the memory allocated for the DWARF unwinder.
          * Traverse all the FDE/CIE lists and remove and free all the
          * memory associated with those data structures.
          */
-        list_for_each_entry_safe(cie, cie_tmp, &dwarf_cie_list, link)
-                kfree(cie);
+        while (*fde_rb_node) {
+                struct dwarf_fde *fde;
 
-        list_for_each_entry_safe(fde, fde_tmp, &dwarf_fde_list, link)
+                fde = rb_entry(*fde_rb_node, struct dwarf_fde, node);
+                rb_erase(*fde_rb_node, &fde_root);
                 kfree(fde);
+        }
+
+        while (*cie_rb_node) {
+                struct dwarf_cie *cie;
+
+                cie = rb_entry(*cie_rb_node, struct dwarf_cie, node);
+                rb_erase(*cie_rb_node, &cie_root);
+                kfree(cie);
+        }
 
         kmem_cache_destroy(dwarf_reg_cachep);
         kmem_cache_destroy(dwarf_frame_cachep);
@@ -1004,6 +1102,8 @@ int module_dwarf_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs,
 
         /* Did we find the .eh_frame section? */
         if (i != hdr->e_shnum) {
+                INIT_LIST_HEAD(&me->arch.cie_list);
+                INIT_LIST_HEAD(&me->arch.fde_list);
                 err = dwarf_parse_section((char *)start, (char *)end, me);
                 if (err) {
                         printk(KERN_WARNING "%s: failed to parse DWARF info\n",
@@ -1024,38 +1124,26 @@ int module_dwarf_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs,
  */
 void module_dwarf_cleanup(struct module *mod)
 {
-        struct dwarf_fde *fde;
-        struct dwarf_cie *cie;
+        struct dwarf_fde *fde, *ftmp;
+        struct dwarf_cie *cie, *ctmp;
         unsigned long flags;
 
         spin_lock_irqsave(&dwarf_cie_lock, flags);
 
-again_cie:
-        list_for_each_entry(cie, &dwarf_cie_list, link) {
-                if (cie->mod == mod)
-                        break;
-        }
-
-        if (&cie->link != &dwarf_cie_list) {
+        list_for_each_entry_safe(cie, ctmp, &mod->arch.cie_list, link) {
                 list_del(&cie->link);
+                rb_erase(&cie->node, &cie_root);
                 kfree(cie);
-                goto again_cie;
         }
 
         spin_unlock_irqrestore(&dwarf_cie_lock, flags);
 
         spin_lock_irqsave(&dwarf_fde_lock, flags);
 
-again_fde:
-        list_for_each_entry(fde, &dwarf_fde_list, link) {
-                if (fde->mod == mod)
-                        break;
-        }
-
-        if (&fde->link != &dwarf_fde_list) {
+        list_for_each_entry_safe(fde, ftmp, &mod->arch.fde_list, link) {
                 list_del(&fde->link);
+                rb_erase(&fde->node, &fde_root);
                 kfree(fde);
-                goto again_fde;
         }
 
         spin_unlock_irqrestore(&dwarf_fde_lock, flags);
@@ -1074,8 +1162,6 @@ again_fde:
 static int __init dwarf_unwinder_init(void)
 {
         int err;
-        INIT_LIST_HEAD(&dwarf_cie_list);
-        INIT_LIST_HEAD(&dwarf_fde_list);
 
         dwarf_frame_cachep = kmem_cache_create("dwarf_frames",
                         sizeof(struct dwarf_frame), 0,
diff --git a/arch/sh/kernel/entry-common.S b/arch/sh/kernel/entry-common.S
index f0abd58c3a69..2b15ae60c3a0 100644
--- a/arch/sh/kernel/entry-common.S
+++ b/arch/sh/kernel/entry-common.S
@@ -70,8 +70,14 @@ ret_from_exception:
         CFI_STARTPROC simple
         CFI_DEF_CFA r14, 0
         CFI_REL_OFFSET 17, 64
-        CFI_REL_OFFSET 15, 0
+        CFI_REL_OFFSET 15, 60
         CFI_REL_OFFSET 14, 56
+        CFI_REL_OFFSET 13, 52
+        CFI_REL_OFFSET 12, 48
+        CFI_REL_OFFSET 11, 44
+        CFI_REL_OFFSET 10, 40
+        CFI_REL_OFFSET 9, 36
+        CFI_REL_OFFSET 8, 32
         preempt_stop()
 ENTRY(ret_from_irq)
         !