Re: [Qemu-devel] [PATCH QEMU v1 4/4] multiboot: fprintf(stderr...) -> error_report()

[P J P <ppandit@redhat.com>]

+-- On Thu, 21 Dec 2017, Jack Schwartz wrote --+
| Change all fprintf(stderr...) calls in hw/i386/multiboot.c to call
| error_report() instead, including the mb_debug macro.  Remove the "\n"
| from strings passed to all modified calls, since error_report() appends
| one.
| 
| Signed-off-by: Jack Schwartz <jack.schwartz@oracle.com>
| Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
| ---
|  hw/i386/multiboot.c | 55 ++++++++++++++++++++++++++++-------------------------
|  1 file changed, 29 insertions(+), 26 deletions(-)
| 
| diff --git a/hw/i386/multiboot.c b/hw/i386/multiboot.c
| index 818728b..d9a0a95 100644
| --- a/hw/i386/multiboot.c
| +++ b/hw/i386/multiboot.c
| @@ -31,12 +31,13 @@
|  #include "hw/loader.h"
|  #include "elf.h"
|  #include "sysemu/sysemu.h"
| +#include "qemu/error-report.h"
|  
|  /* Show multiboot debug output */
|  //#define DEBUG_MULTIBOOT
|  
|  #ifdef DEBUG_MULTIBOOT
| -#define mb_debug(a...) fprintf(stderr, ## a)
| +#define mb_debug(a...) error_report(a)
|  #else
|  #define mb_debug(a...)
|  #endif
| @@ -137,7 +138,7 @@ static void mb_add_mod(MultibootState *s,
|      stl_p(p + MB_MOD_END,     end);
|      stl_p(p + MB_MOD_CMDLINE, cmdline_phys);
|  
| -    mb_debug("mod%02d: "TARGET_FMT_plx" - "TARGET_FMT_plx"\n",
| +    mb_debug("mod%02d: "TARGET_FMT_plx" - "TARGET_FMT_plx,
|               s->mb_mods_count, start, end);
|  
|      s->mb_mods_count++;
| @@ -179,12 +180,12 @@ int load_multiboot(FWCfgState *fw_cfg,
|      if (!is_multiboot)
|          return 0; /* no multiboot */
|  
| -    mb_debug("qemu: I believe we found a multiboot image!\n");
| +    mb_debug("qemu: I believe we found a multiboot image!");
|      memset(bootinfo, 0, sizeof(bootinfo));
|      memset(&mbs, 0, sizeof(mbs));
|  
|      if (flags & 0x00000004) { /* MULTIBOOT_HEADER_HAS_VBE */
| -        fprintf(stderr, "qemu: multiboot knows VBE. we don't.\n");
| +        error_report("qemu: multiboot knows VBE. we don't.");
|      }
|      if (!(flags & 0x00010000)) { /* MULTIBOOT_HEADER_HAS_ADDR */
|          uint64_t elf_entry;
| @@ -193,7 +194,7 @@ int load_multiboot(FWCfgState *fw_cfg,
|          fclose(f);
|  
|          if (((struct elf64_hdr*)header)->e_machine == EM_X86_64) {
| -            fprintf(stderr, "Cannot load x86-64 image, give a 32bit one.\n");
| +            error_report("Cannot load x86-64 image, give a 32bit one.");
|              exit(1);
|          }
|  
| @@ -201,7 +202,7 @@ int load_multiboot(FWCfgState *fw_cfg,
|                                 &elf_low, &elf_high, 0, I386_ELF_MACHINE,
|                                 0, 0);
|          if (kernel_size < 0) {
| -            fprintf(stderr, "Error while loading elf kernel\n");
| +            error_report("Error while loading elf kernel");
|              exit(1);
|          }
|          mh_load_addr = elf_low;
| @@ -210,12 +211,13 @@ int load_multiboot(FWCfgState *fw_cfg,
|  
|          mbs.mb_buf = g_malloc(mb_kernel_size);
|          if (rom_copy(mbs.mb_buf, mh_load_addr, mb_kernel_size) != mb_kernel_size) {
| -            fprintf(stderr, "Error while fetching elf kernel from rom\n");
| +            error_report("Error while fetching elf kernel from rom");
|              exit(1);
|          }
|  
| -        mb_debug("qemu: loading multiboot-elf kernel (%#x bytes) with entry %#zx\n",
| -                  mb_kernel_size, (size_t)mh_entry_addr);
| +        mb_debug("qemu: loading multiboot-elf kernel "
| +                 "(%#x bytes) with entry %#zx",
| +                 mb_kernel_size, (size_t)mh_entry_addr);
|      } else {
|          /* Valid if mh_flags sets MULTIBOOT_HEADER_HAS_ADDR. */
|          uint32_t mh_header_addr = ldl_p(header+i+12);
| @@ -224,7 +226,7 @@ int load_multiboot(FWCfgState *fw_cfg,
|  
|          mh_load_addr = ldl_p(header+i+16);
|          if (mh_header_addr < mh_load_addr) {
| -            fprintf(stderr, "invalid load_addr address\n");
| +            error_report("invalid load_addr address");
|              exit(1);
|          }
|  
| @@ -234,20 +236,20 @@ int load_multiboot(FWCfgState *fw_cfg,
|  
|          if (mh_load_end_addr) {
|              if (mh_load_end_addr < mh_load_addr) {
| -                fprintf(stderr, "invalid load_end_addr address\n");
| +                error_report("invalid load_end_addr address");
|                  exit(1);
|              }
|              mb_load_size = mh_load_end_addr - mh_load_addr;
|          } else {
|              if (kernel_file_size < mb_kernel_text_offset) {
| -                fprintf(stderr, "invalid kernel_file_size\n");
| +                error_report("invalid kernel_file_size");
|                  exit(1);
|              }
|              mb_load_size = kernel_file_size - mb_kernel_text_offset;
|          }
|          if (mh_bss_end_addr) {
|              if (mh_bss_end_addr < (mh_load_addr + mb_load_size)) {
| -                fprintf(stderr, "invalid bss_end_addr address\n");
| +                error_report("invalid bss_end_addr address");
|                  exit(1);
|              }
|              mb_kernel_size = mh_bss_end_addr - mh_load_addr;
| @@ -255,17 +257,17 @@ int load_multiboot(FWCfgState *fw_cfg,
|              mb_kernel_size = mb_load_size;
|          }
|  
| -        mb_debug("multiboot: header_addr = %#x\n", mh_header_addr);
| -        mb_debug("multiboot: load_addr = %#x\n", mh_load_addr);
| -        mb_debug("multiboot: load_end_addr = %#x\n", mh_load_end_addr);
| -        mb_debug("multiboot: bss_end_addr = %#x\n", mh_bss_end_addr);
| -        mb_debug("qemu: loading multiboot kernel (%#x bytes) at %#x\n",
| +        mb_debug("multiboot: header_addr = %#x", mh_header_addr);
| +        mb_debug("multiboot: load_addr = %#x", mh_load_addr);
| +        mb_debug("multiboot: load_end_addr = %#x", mh_load_end_addr);
| +        mb_debug("multiboot: bss_end_addr = %#x", mh_bss_end_addr);
| +        mb_debug("qemu: loading multiboot kernel (%#x bytes) at %#x",
|                   mb_load_size, mh_load_addr);
|  
|          mbs.mb_buf = g_malloc(mb_kernel_size);
|          fseek(f, mb_kernel_text_offset, SEEK_SET);
|          if (fread(mbs.mb_buf, 1, mb_load_size, f) != mb_load_size) {
| -            fprintf(stderr, "fread() failed\n");
| +            error_report("fread() failed");
|              exit(1);
|          }
|          memset(mbs.mb_buf + mb_load_size, 0, mb_kernel_size - mb_load_size);
| @@ -319,10 +321,10 @@ int load_multiboot(FWCfgState *fw_cfg,
|              hwaddr c = mb_add_cmdline(&mbs, tmpbuf);
|              if ((next_space = strchr(tmpbuf, ' ')))
|                  *next_space = '\0';
| -            mb_debug("multiboot loading module: %s\n", tmpbuf);
| +            mb_debug("multiboot loading module: %s", tmpbuf);
|              mb_mod_length = get_image_size(tmpbuf);
|              if (mb_mod_length < 0) {
| -                fprintf(stderr, "Failed to open file '%s'\n", tmpbuf);
| +                error_report("Failed to open file '%s'", tmpbuf);
|                  exit(1);
|              }
|  
| @@ -333,7 +335,7 @@ int load_multiboot(FWCfgState *fw_cfg,
|              mb_add_mod(&mbs, mbs.mb_buf_phys + offs,
|                         mbs.mb_buf_phys + offs + mb_mod_length, c);
|  
| -            mb_debug("mod_start: %p\nmod_end:   %p\n  cmdline: "TARGET_FMT_plx"\n",
| +            mb_debug("mod_start: %p\nmod_end:   %p\n  cmdline: "TARGET_FMT_plx,
|                       (char *)mbs.mb_buf + offs,
|                       (char *)mbs.mb_buf + offs + mb_mod_length, c);
|              initrd_filename = next_initrd+1;
| @@ -361,10 +363,11 @@ int load_multiboot(FWCfgState *fw_cfg,
|      stl_p(bootinfo + MBI_BOOT_DEVICE, 0x8000ffff); /* XXX: use the -boot switch? */
|      stl_p(bootinfo + MBI_MMAP_ADDR,   ADDR_E820_MAP);
|  
| -    mb_debug("multiboot: entry_addr = %#x\n", mh_entry_addr);
| -    mb_debug("           mb_buf_phys   = "TARGET_FMT_plx"\n", mbs.mb_buf_phys);
| -    mb_debug("           mod_start     = "TARGET_FMT_plx"\n", mbs.mb_buf_phys + mbs.offset_mods);
| -    mb_debug("           mb_mods_count = %d\n", mbs.mb_mods_count);
| +    mb_debug("multiboot: entry_addr = %#x", mh_entry_addr);
| +    mb_debug("           mb_buf_phys   = "TARGET_FMT_plx, mbs.mb_buf_phys);
| +    mb_debug("           mod_start     = "TARGET_FMT_plx,
| +             mbs.mb_buf_phys + mbs.offset_mods);
| +    mb_debug("           mb_mods_count = %d", mbs.mb_mods_count);
|  
|      /* save bootinfo off the stack */
|      mb_bootinfo_data = g_memdup(bootinfo, sizeof(bootinfo));
| 

Looks okay.

It maybe good to have version of error_report() which calls exit(1) too. I 
guess err(3) family of functions isn't used because they are nonstandard.

Thank you.
--
Prasad J Pandit / Red Hat Product Security Team
47AF CE69 3A90 54AA 9045 1053 DD13 3D32 FE5B 041F