KVM: Rework of guest debug state writing

So far we synchronized any dirty VCPU state back into the kernel before
updating the guest debug state. This was a tribute to a deficite in x86
kernels before 2.6.33. But as this is an arch-dependent issue, it is
better handle in the x86 part of KVM and remove the writeback point for
generic code. This also avoids overwriting the flushed state later on if
user space decides to change some more registers before resuming the
guest.

We furthermore need to reinject guest exceptions via the appropriate
mechanism. That is KVM_SET_GUEST_DEBUG for older kernels and
KVM_SET_VCPU_EVENTS for recent ones. Using both mechanisms at the same
time will cause state corruptions.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
3 files changed
tree: d49073cd79a4987ded9b57a1b057a6329877160f
  1. audio/
  2. block/
  3. bsd-user/
  4. darwin-user/
  5. default-configs/
  6. docs/
  7. fpu/
  8. gdb-xml/
  9. hw/
  10. linux-user/
  11. net/
  12. pc-bios/
  13. QMP/
  14. roms/
  15. slirp/
  16. sysconfigs/
  17. target-alpha/
  18. target-arm/
  19. target-cris/
  20. target-i386/
  21. target-m68k/
  22. target-microblaze/
  23. target-mips/
  24. target-ppc/
  25. target-s390x/
  26. target-sh4/
  27. target-sparc/
  28. tcg/
  29. tests/
  30. .gitignore
  31. .gitmodules
  32. a.out.h
  33. acl.c
  34. acl.h
  35. aes.c
  36. aes.h
  37. aio.c
  38. alpha-dis.c
  39. alpha.ld
  40. arm-dis.c
  41. arm-semi.c
  42. arm.ld
  43. async.c
  44. balloon.h
  45. block-migration.c
  46. block-migration.h
  47. block.c
  48. block.h
  49. block_int.h
  50. bswap.h
  51. bt-host.c
  52. bt-host.h
  53. bt-vhci.c
  54. buffered_file.c
  55. buffered_file.h
  56. cache-utils.c
  57. cache-utils.h
  58. Changelog
  59. check-qdict.c
  60. check-qfloat.c
  61. check-qint.c
  62. check-qjson.c
  63. check-qlist.c
  64. check-qstring.c
  65. cmd.c
  66. cmd.h
  67. cocoa.m
  68. CODING_STYLE
  69. config.h
  70. configure
  71. console.c
  72. console.h
  73. COPYING
  74. COPYING.LIB
  75. cpu-all.h
  76. cpu-common.h
  77. cpu-defs.h
  78. cpu-exec.c
  79. create_config
  80. cris-dis.c
  81. curses.c
  82. curses_keys.h
  83. cutils.c
  84. d3des.c
  85. d3des.h
  86. def-helper.h
  87. device_tree.c
  88. device_tree.h
  89. dis-asm.h
  90. disas.c
  91. disas.h
  92. dma-helpers.c
  93. dma.h
  94. dyngen-exec.h
  95. elf.h
  96. envlist.c
  97. envlist.h
  98. exec-all.h
  99. exec.c
  100. feature_to_c.sh
  101. gdbstub.c
  102. gdbstub.h
  103. gen-icount.h
  104. host-utils.c
  105. host-utils.h
  106. hpet.h
  107. hppa-dis.c
  108. hppa.ld
  109. hxtool
  110. i386-dis.c
  111. i386.ld
  112. ia64.ld
  113. input.c
  114. ioport-user.c
  115. ioport.c
  116. ioport.h
  117. json-lexer.c
  118. json-lexer.h
  119. json-parser.c
  120. json-parser.h
  121. json-streamer.c
  122. json-streamer.h
  123. keymaps.c
  124. keymaps.h
  125. kvm-all.c
  126. kvm.h
  127. libfdt_env.h
  128. LICENSE
  129. linux-aio.c
  130. m68k-dis.c
  131. m68k-semi.c
  132. m68k.ld
  133. MAINTAINERS
  134. Makefile
  135. Makefile.hw
  136. Makefile.objs
  137. Makefile.target
  138. Makefile.user
  139. microblaze-dis.c
  140. migration-exec.c
  141. migration-fd.c
  142. migration-tcp.c
  143. migration-unix.c
  144. migration.c
  145. migration.h
  146. mips-dis.c
  147. mips.ld
  148. module.c
  149. module.h
  150. monitor.c
  151. monitor.h
  152. nbd.c
  153. nbd.h
  154. net-checksum.c
  155. net.c
  156. net.h
  157. osdep.c
  158. osdep.h
  159. path.c
  160. pci-ids.txt
  161. posix-aio-compat.c
  162. ppc-dis.c
  163. ppc.ld
  164. ppc64.ld
  165. qbool.c
  166. qbool.h
  167. qdict-test-data.txt
  168. qdict.c
  169. qdict.h
  170. qemu-aio.h
  171. qemu-barrier.h
  172. qemu-binfmt-conf.sh
  173. qemu-char.c
  174. qemu-char.h
  175. qemu-common.h
  176. qemu-config.c
  177. qemu-config.h
  178. qemu-doc.texi
  179. qemu-img-cmds.hx
  180. qemu-img.c
  181. qemu-img.texi
  182. qemu-io.c
  183. qemu-lock.h
  184. qemu-log.h
  185. qemu-malloc.c
  186. qemu-monitor.hx
  187. qemu-nbd.c
  188. qemu-nbd.texi
  189. qemu-objects.h
  190. qemu-option.c
  191. qemu-option.h
  192. qemu-options.hx
  193. qemu-queue.h
  194. qemu-sockets.c
  195. qemu-tech.texi
  196. qemu-thread.c
  197. qemu-thread.h
  198. qemu-timer.h
  199. qemu-tool.c
  200. qemu.sasl
  201. qemu_socket.h
  202. qerror.c
  203. qerror.h
  204. qfloat.c
  205. qfloat.h
  206. qint.c
  207. qint.h
  208. qjson.c
  209. qjson.h
  210. qlist.c
  211. qlist.h
  212. qobject.h
  213. qstring.c
  214. qstring.h
  215. readline.c
  216. readline.h
  217. README
  218. rules.mak
  219. rwhandler.c
  220. rwhandler.h
  221. s390-dis.c
  222. s390.ld
  223. savevm.c
  224. sdl.c
  225. sdl_keysym.h
  226. sdl_zoom.c
  227. sdl_zoom.h
  228. sdl_zoom_template.h
  229. sh4-dis.c
  230. softmmu-semi.h
  231. softmmu_defs.h
  232. softmmu_exec.h
  233. softmmu_header.h
  234. softmmu_template.h
  235. sparc-dis.c
  236. sparc.ld
  237. sparc64.ld
  238. sysemu.h
  239. targphys.h
  240. tcg-runtime.c
  241. texi2pod.pl
  242. thunk.c
  243. thunk.h
  244. TODO
  245. translate-all.c
  246. uboot_image.h
  247. usb-bsd.c
  248. usb-linux.c
  249. usb-stub.c
  250. VERSION
  251. vgafont.h
  252. vl.c
  253. vnc-auth-sasl.c
  254. vnc-auth-sasl.h
  255. vnc-auth-vencrypt.c
  256. vnc-auth-vencrypt.h
  257. vnc-tls.c
  258. vnc-tls.h
  259. vnc.c
  260. vnc.h
  261. vnc_keysym.h
  262. vnchextile.h
  263. x86_64.ld
  264. x_keymap.c
  265. x_keymap.h