Changeset e3038b4 in mainline for kernel/arch/amd64/src/asm_utils.S

Timestamp:

2010-06-28T22:45:51Z (15 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

49eb681

Parents:

05e3cb8 (diff), e4a4b44 (diff)
Note: this is a merge changeset, the changes displayed below correspond to the merge itself.
Use the (diff) links above to see all the changes relative to each parent.

Message:

Merge unified panic architecture (Phase 1).

Note that this is still work in progress as there are the following sharp edges:

• imprecise detection of read/write accesses on some architectures
• missing or imperfect capability to print stack traces on some architectures
• istate_t on some architectures may contain too little valuable information
• basically all trap frames need to be reorganized to look like a normal stack frame on the stack trace so that there are no missing frames
• panic_common() could print more information about the current context such as the task name, thread name, ASID etc.
• functions that call panic_*() should be protected against inlining to avoid missing or confusing stack frames in the stack trace

File:

• kernel/arch/amd64/src/asm_utils.S (modified) (3 diffs)

kernel/arch/amd64/src/asm_utils.S

@@ -51 +51 @@
 .global interrupt_handlers
 .global syscall_entry
-.global panic_printf
-
-panic_printf:
-        movabsq $halt, %rax
-        movq %rax, (%rsp)
-        jmp printf
-
 .global cpuid
 .global has_cpuid
@@ -234 +227 @@
         save_all_gpr
         cld
-        
-        # Stop stack traces here
-        xorq %rbp, %rbp
-        
-        movq $(\i), %rdi    # %rdi - first parameter
-        movq %rsp, %rsi     # %rsi - pointer to istate
-        call exc_dispatch   # exc_dispatch(i, istate)
+
+        #
+        # Stop stack traces here if we came from userspace.
+        #
+        movq %cs, %rax
+        xorq %rdx, %rdx
+        cmpq %rax, IREGISTER_SPACE+16(%rsp)
+        cmovneq %rdx, %rbp
+
+        movq $(\i), %rdi        # %rdi - first parameter
+        movq %rsp, %rsi         # %rsi - pointer to istate
+        call exc_dispatch       # exc_dispatch(i, istate)
         
         restore_all_gpr
@@ -290 +288 @@
         pushq %rcx
         pushq %r11
-        
-        movq %r10, %rcx   # Copy the 4th argument where it is expected 
+        pushq %rbp
+
+        xorq %rbp, %rbp         # stop the stack traces here
+
+        movq %r10, %rcx         # Copy the 4th argument where it is expected 
         pushq %rax
         call syscall_handler
         addq $8, %rsp
-        
+                
+        popq %rbp
         popq %r11
         popq %rcx