On Tue, 8 Jun 2021 23:46:05 +1000, Michael Ellerman wrote:
In commit 96d7a4e06fab ("powerpc/signal64: Rewrite handle_rt_signal64()
to minimise uaccess switches") the 64-bit signal code was rearranged to
use user_write_access_begin/end().
As part of that change the call to copy_siginfo_to_user() was moved
later in the function, so that it could be done after the
user_write_access_end().
[...]
Applied to powerpc/fixes.
[1/1] powerpc/signal64: Copy siginfo before changing regs->nip
https://git.kernel.org/powerpc/c/e41d6c3f4f9b4804e53ca87aba8ee11ada606c77
cheers