K 10
svn:author
V 8
jhibbits
K 8
svn:date
V 27
2018-05-30T03:48:27.771316Z
K 7
svn:log
V 219
Protect dtrace_getpcstack() from a NULL stack pointer in a trap frame

Found when trying to use lockstat on a POWER9, the stack pointer (r1) could
be NULL, and result in a NULL pointer dereference, crashing the kernel.

END