xtensa: expose syscall through user_pt_regs
authorMax Filippov <jcmvbkbc@gmail.com>
Sun, 19 Jul 2020 00:47:43 +0000 (17:47 -0700)
committerMax Filippov <jcmvbkbc@gmail.com>
Tue, 28 Jul 2020 07:57:05 +0000 (00:57 -0700)
commit8b7a87a03f7c15c7a1e1647c3527292604e80f6f
treed74522605da28d8d06f4874f8f4822a9657adb78
parentef1a935c08ea97436f62edb0b1427d60e31b777b
xtensa: expose syscall through user_pt_regs

Use one of the reserved slots in struct user_pt_regs to return syscall
number in the GPR regset. Update syscall number from the GPR regset only
when it's non-zero.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
arch/xtensa/include/uapi/asm/ptrace.h
arch/xtensa/kernel/ptrace.c