Pull x86 fixes from Thomas Gleixner:
"Three fixes all related to #DB:
- Handle the BTF bit correctly so it doesn't get lost due to a kernel
#DB
- Only clear and set the virtual DR6 value used by ptrace on user
space triggered #DB. A kernel #DB must leave it alone to ensure
data consistency for ptrace.
- Make the bitmasking of the virtual DR6 storage correct so it does
not lose DR_STEP"
* tag 'x86-urgent-2020-11-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/debug: Fix DR_STEP vs ptrace_get_debugreg(6)
x86/debug: Only clear/set ->virtual_dr6 for userspace #DB
x86/debug: Fix BTF handling