monitor: Fix crashes when using HMP commands without CPU

When running certain HMP commands ("info registers", "info cpustats",
"info tlb", "nmi", "memsave" or dumping virtual memory) with the "none"
machine, QEMU crashes with a segmentation fault. This happens because the
"none" machine does not have any CPUs by default, but these HMP commands
did not check for a valid CPU pointer yet. Add such checks now, so we get
an error message about the missing CPU instead.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <1484309555-1935-1-git-send-email-thuth@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
7 files changed
tree: 95528d10774a6b5021083310dee65c7bbe376274
  1. audio/
  2. backends/
  3. block/
  4. bsd-user/
  5. chardev/
  6. contrib/
  7. crypto/
  8. default-configs/
  9. disas/
  10. docs/
  11. fpu/
  12. fsdev/
  13. gdb-xml/
  14. hw/
  15. include/
  16. io/
  17. libdecnumber/
  18. linux-headers/
  19. linux-user/
  20. migration/
  21. nbd/
  22. net/
  23. pc-bios/
  24. po/
  25. qapi/
  26. qga/
  27. qobject/
  28. qom/
  29. replay/
  30. roms/
  31. scripts/
  32. slirp/
  33. stubs/
  34. target/
  35. tcg/
  36. tests/
  37. trace/
  38. ui/
  39. util/
  40. .dir-locals.el
  41. .exrc
  42. .gitignore
  43. .gitmodules
  44. .mailmap
  45. .travis.yml
  46. accel.c
  47. arch_init.c
  48. atomic_template.h
  49. balloon.c
  50. block.c
  51. blockdev-nbd.c
  52. blockdev.c
  53. blockjob.c
  54. bootdevice.c
  55. bt-host.c
  56. bt-vhci.c
  57. Changelog
  58. CODING_STYLE
  59. configure
  60. COPYING
  61. COPYING.LIB
  62. cpu-exec-common.c
  63. cpu-exec.c
  64. cpus-common.c
  65. cpus.c
  66. cputlb.c
  67. device-hotplug.c
  68. device_tree.c
  69. disas.c
  70. dma-helpers.c
  71. dump.c
  72. exec.c
  73. gdbstub.c
  74. HACKING
  75. hax-stub.c
  76. hmp-commands-info.hx
  77. hmp-commands.hx
  78. hmp.c
  79. hmp.h
  80. ioport.c
  81. iothread.c
  82. kvm-all.c
  83. kvm-stub.c
  84. LICENSE
  85. MAINTAINERS
  86. Makefile
  87. Makefile.objs
  88. Makefile.target
  89. memory.c
  90. memory_ldst.inc.c
  91. memory_mapping.c
  92. module-common.c
  93. monitor.c
  94. numa.c
  95. os-posix.c
  96. os-win32.c
  97. page_cache.c
  98. qapi-schema.json
  99. qdev-monitor.c
  100. qdict-test-data.txt
  101. qemu-bridge-helper.c
  102. qemu-doc.texi
  103. qemu-ga.texi
  104. qemu-img-cmds.hx
  105. qemu-img.c
  106. qemu-img.texi
  107. qemu-io-cmds.c
  108. qemu-io.c
  109. qemu-nbd.c
  110. qemu-nbd.texi
  111. qemu-option-trace.texi
  112. qemu-options-wrapper.h
  113. qemu-options.h
  114. qemu-options.hx
  115. qemu-seccomp.c
  116. qemu-tech.texi
  117. qemu.nsi
  118. qemu.sasl
  119. qmp.c
  120. qtest.c
  121. README
  122. replication.c
  123. replication.h
  124. rules.mak
  125. softmmu_template.h
  126. spice-qemu-char.c
  127. tcg-runtime.c
  128. tci.c
  129. thunk.c
  130. tpm.c
  131. trace-events
  132. translate-all.c
  133. translate-all.h
  134. translate-common.c
  135. user-exec-stub.c
  136. user-exec.c
  137. VERSION
  138. version.rc
  139. vl.c
  140. xen-common-stub.c
  141. xen-common.c
  142. xen-hvm-stub.c
  143. xen-hvm.c
  144. xen-mapcache.c