| commit | 5b0e508415a83989fe704b4718a1a214bc333ca7 | |
| author | Jan Beulich <jbeulich@novell.com> | |
| Mon, 10 Mar 2008 13:11:17 +0000 (10 13:11 +0000) | ||
| committer | Ingo Molnar <mingo@elte.hu> | |
| Thu, 17 Apr 2008 15:40:58 +0000 (17 17:40 +0200) | ||
| tree | bf73f1e6b944c190441413cedfb49b05e04ffe6b | treesnapshot (tar.gz zip) |
| parent | f694010185c429629ad5a65245da08103e611852 | commitdiff |
x86: prevent unconditional writes to DebugCtl MSR
Otherwise, enabling (or better, subsequent disabling) of single
stepping would cause a kernel oops on CPUs not having this MSR.
The patch could have been added a conditional to the MSR write in
user_disable_single_step(), but centralizing the updates seems safer
and (looking forward) better manageable.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Cc: Markus Metzger <markus.t.metzger@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Otherwise, enabling (or better, subsequent disabling) of single
stepping would cause a kernel oops on CPUs not having this MSR.
The patch could have been added a conditional to the MSR write in
user_disable_single_step(), but centralizing the updates seems safer
and (looking forward) better manageable.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Cc: Markus Metzger <markus.t.metzger@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>