Red Hat Bugzilla – Bug 721283
CVE-2011-2693 kernel: panic with NMI enabled while using perf
Last modified: 2016-11-08 10:55:14 EST
Kernel panic when using perf and nmi_watchdog together. The following patch solves the problems introduced by Robert's commit 41bf498 and reported by Arun Sharma. This commit gets rid of the base + index notation for reading and writing PMU msrs. The problem is that for fixed counters, the new calculation for the base did not take into account the fixed counter indexes, thus all fixed counters were read/written from fixed counter 0. Although all fixed counters share the same config MSR, they each have their own counter register. Without: $ task -e unhalted_core_cycles -e instructions_retired -e baclears noploop 1 noploop for 1 seconds 242202299 unhalted_core_cycles (0.00% scaling, ena=1000790892, run=1000790892) 2389685946 instructions_retired (0.00% scaling, ena=1000790892, run=1000790892) 49473 baclears (0.00% scaling, ena=1000790892, run=1000790892) With: $ task -e unhalted_core_cycles -e instructions_retired -e baclears noploop 1 noploop for 1 seconds 2392703238 unhalted_core_cycles (0.00% scaling, ena=1000840809, run=1000840809) 2389793744 instructions_retired (0.00% scaling, ena=1000840809, run=1000840809) 47863 baclears (0.00% scaling, ena=1000840809, run=1000840809) Upstream commit: http://git.kernel.org/linus/fc66c5210ec2539e800e87d7b3a985323c7be96e
Upstream commit: http://git.kernel.org/linus/fc66c5210ec2539e800e87d7b3a985323c7be96e
*** This bug has been marked as a duplicate of bug 719228 ***
(In reply to comment #24) > > *** This bug has been marked as a duplicate of bug 719228 *** It was found to be the same issue as CVE-2011-2521. CVE-2011-2693 is rejected.