On 07/29/2016 10:29 AM, Andy Lutomirski wrote:
quoted
quoted
In the end, this ensures that threads which do not know how to
manage their own pkey rights can not do damage to data which is
pkey-protected.
I think you missed the fpu__clear() caller in kernel/fpu/signal.c.
ISTM it might be more comprehensible to change fpu__clear in general
and then special case things you want to behave differently.
The code actually already patched the generic fpu__clear():
fpu__clear() ->
copy_init_fpstate_to_fpregs() ->
copy_init_pkru_to_fpregs()
So I think it hit the case you are talking about.