More logging

Author: kereoz

cpu-exec.c

@@ -29,6 +29,8 @@
 #include "qemu/rcu.h"
 
 /* -icount align implementation. */
+uint64_t tracer_code_start,
+        tracer_code_end;
 
 typedef struct SyncClocks {
     int64_t diff_clk;
@@ -493,16 +495,23 @@ int cpu_exec(CPUArchState *env)
                     tcg_ctx.tb_ctx.tb_invalidated_flag = 0;
                 }
                 if (qemu_loglevel_mask(CPU_LOG_EXEC)) {
-                    qemu_log("Trace %p [" TARGET_FMT_lx "] %s\n",
-                             tb->tc_ptr, tb->pc, lookup_symbol(tb->pc));
+                    /* tracer only cares about transitions in .text */
+                    if (tb->pc >= tracer_code_start && tb->pc <= tracer_code_end)
+                        qemu_log("Trace %p [" TARGET_FMT_lx "] %s\n",
+                                 tb->tc_ptr, tb->pc, lookup_symbol(tb->pc));
                 }
                 /* see if we can patch the calling TB. When the TB
                    spans two pages, we cannot safely do a direct
                    jump. */
+
+                /* tracer needs to see every basic block transition */
+                /*
                 if (next_tb != 0 && tb->page_addr[1] == -1) {
                     tb_add_jump((TranslationBlock *)(next_tb & ~TB_EXIT_MASK),
                                 next_tb & TB_EXIT_MASK, tb);
                 }
+                */
+
                 have_tb_lock = false;
                 spin_unlock(&tcg_ctx.tb_ctx.tb_lock);
 

linux-user/elfload.c

@@ -28,6 +28,8 @@
 
 #define ELF_OSABI   ELFOSABI_SYSV
 
+extern uint64_t tracer_code_start, tracer_code_end;
+
 /* from personality.h */
 
 /*
@@ -1785,6 +1787,7 @@ static void load_elf_image(const char *image_name, int image_fd,
                            struct image_info *info, char **pinterp_name,
                            char bprm_buf[BPRM_BUF_SIZE])
 {
+	printf("[tracer-debug] Loading image %s\n", image_name);
     struct elfhdr *ehdr = (struct elfhdr *)bprm_buf;
     struct elf_phdr *phdr;
     abi_ulong load_addr, load_bias, loaddr, hiaddr, error;
@@ -1922,9 +1925,12 @@ static void load_elf_image(const char *image_name, int image_fd,
             if (elf_prot & PROT_EXEC) {
                 if (vaddr < info->start_code) {
                     info->start_code = vaddr;
+                    if (!tracer_code_start) tracer_code_start = vaddr;
                 }
                 if (vaddr_ef > info->end_code) {
                     info->end_code = vaddr_ef;
+					printf("[tracer-debug] highest address of mapped code: 0x%lx\n", (unsigned long)vaddr_ef);
+                    if (!tracer_code_end) tracer_code_end = vaddr_ef;
                 }
             }
             if (elf_prot & PROT_WRITE) {

linux-user/flatload.c

@@ -683,6 +683,8 @@ static int load_flat_shared_library(int id, struct lib_info *libs)
 	/* Create the file name */
 	sprintf(buf, "/lib/lib%d.so", id);
 
+	printf("[tracer-debug] Load_flat_so %s\n", buf);
+
 	/* Open the file up */
 	bprm.filename = buf;
 	bprm.file = open_exec(bprm.filename);
@@ -714,6 +716,8 @@ int load_flt_binary(struct linux_binprm *bprm, struct image_info *info)
     int res;
     int i, j;
 
+	printf("[tracer-debug] Load_flat %s\n", bprm->filename);
+
     memset(libinfo, 0, sizeof(libinfo));
     /*
      * We have to add the size of our arguments to our stack size

linux-user/mmap.c

@@ -33,6 +33,8 @@
 
 //#define DEBUG_MMAP
 
+extern uint64_t tracer_code_end;
+
 static pthread_mutex_t mmap_mutex = PTHREAD_MUTEX_INITIALIZER;
 static __thread int mmap_lock_count;
 
@@ -372,6 +374,12 @@ abi_long target_mmap(abi_ulong start, abi_ulong len, int prot,
 {
     abi_ulong ret, end, real_start, real_end, retaddr, host_offset, host_len;
 
+	if (len+start > tracer_code_end)
+	{
+		printf("[tracer-debug] mmap: tracer_code_end updated: 0x%lx\n", (unsigned long)len+start);
+		tracer_code_end = len+start;
+	}
+
     mmap_lock();
 #ifdef DEBUG_MMAP
     {

linux-user/syscall.c

@@ -204,6 +204,8 @@ static type name (type1 arg1,type2 arg2,type3 arg3,type4 arg4,type5 arg5,	\
 #define TARGET_NR__llseek TARGET_NR_llseek
 #endif
 
+static bool last_read_empty = false;
+
 #ifdef __NR_gettid
 _syscall0(int, gettid)
 #else
@@ -671,6 +673,7 @@ abi_long do_brk(abi_ulong new_brk)
         }
 	target_brk = new_brk;
         DEBUGF_BRK(TARGET_ABI_FMT_lx " (new_brk <= brk_page)\n", target_brk);
+		printf("[tracer-debug] New BRK: 0x%lx\n", (unsigned long) target_brk);
     	return target_brk;
     }
 
@@ -699,6 +702,7 @@ abi_long do_brk(abi_ulong new_brk)
         brk_page = HOST_PAGE_ALIGN(target_brk);
         DEBUGF_BRK(TARGET_ABI_FMT_lx " (mapped_addr == brk_page)\n",
             target_brk);
+		printf("[tracer-debug] New BRK: 0x%lx\n", (unsigned long) target_brk);
         return target_brk;
     } else if (mapped_addr != -1) {
         /* Mapped but at wrong address, meaning there wasn't actually
@@ -718,6 +722,7 @@ abi_long do_brk(abi_ulong new_brk)
     return -TARGET_ENOMEM;
 #endif
     /* For everything else, return the previous break. */
+	printf("[tracer-debug] BRK unchanged (0x%lx\n)", (unsigned long) target_brk);
     return target_brk;
 }
 
@@ -5572,6 +5577,14 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
             if (!(p = lock_user(VERIFY_WRITE, arg2, arg3, 0)))
                 goto efault;
             ret = get_errno(read(arg1, p, arg3));
+            if (ret == 0) {
+                if (last_read_empty) {
+                    exit_group(1);
+                }
+                last_read_empty = true;
+            } else {
+                last_read_empty = false;
+            }
             unlock_user(p, arg2, ret);
         }
         break;