https://bugzilla.kernel.org/show_bug.cgi?id=219787 --- Comment #16 from Ravi Bangoria (ravi.bangoria@xxxxxxx) --- (In reply to Sean Christopherson from comment #13) > And does AMD do _any_ testing? This doesn't even require a full reproducer, > e.g. the existing debug KVM-Unit-Test fails on my system (Turin) without ever > generating a split/bus lock. AFAICT, the CPU is reporting bus locks in DR6 > on > #DBs that are most definitely not due to bus locks. It seems, the CPU is preserving SW written DR6[BusLockDetected] while generating the #DB when the CPL is 0 and DEBUGCTL[BusLockTrapEn] is set. Since most of the x86/debug.c KUT tests clears DR6[BusLockDetected] before executing the test, the bit remains cleared at the exception time which causes tests to fail. -- You may reply to this email to add a comment. You are receiving this mail because: You are watching the assignee of the bug.
