linux.git/arch/xtensa/kernel/ptrace.c, branch v5.4.55

xtensa: implement syscall tracepoints

2018-12-17T21:50:25+00:00

Add TIF_SYSCALL_TRACEPOINT flag definition; add _TIF_SYSCALL_TRACEPOINT
to _TIF_WORK_MASK. Call trace_sys_enter from do_syscall_trace_enter and
trace_sys_exit from do_syscall_trace_leave when TIF_SYSCALL_TRACEPOINT
flag is set.
Add declaration of sys_call_table to arch/xtensa/include/asm/syscall.h
Add definition of NR_syscalls to arch/xtensa/include/asm/unistd.h
Select HAVE_SYSCALL_TRACEPOINTS.

This change allows tracing each syscall entry and exit through the
ftrace mechanism.

Signed-off-by: Max Filippov

xtensa: implement TIE regset

2018-12-17T21:48:22+00:00

Put all coprocessors and non-coprocessor TIE state into the REGSET_TIE.
Mark TIE regset with NT_PRFPREG note type.
Reimplement ptrace_getxregs and ptrace_setxregs using REGSET_TIE.

Signed-off-by: Max Filippov

xtensa: implement task_user_regset_view

2018-12-17T21:48:21+00:00

- define struct user_pt_regs in the arch/xtensa/include/uapi/asm/ptrace.h
  with the same layout as xtensa_gregset_t; make xtensa_gregset_t a
  typedef;
- define REGSET_GPR regset, implement register get and set functions;
- define task_user_regset_view function and expose REGSET_GPR.

Signed-off-by: Max Filippov

xtensa: call do_syscall_trace_{enter,leave} selectively

2018-12-17T21:48:21+00:00

Check whether calls to do_syscall_trace_{enter,leave} are necessary in
the system_call function. Define _TIF_WORK_MASK to a bitmask of flags
that reuire the calls. Fix comment.

Signed-off-by: Max Filippov

xtensa: use NO_SYSCALL instead of -1

2018-12-17T21:48:21+00:00

For the sake of clarity define macro NO_SYSCALL and use it for
setting/checking struct pt_regs::syscall field.

Signed-off-by: Max Filippov

xtensa: drop custom PTRACE_{PEEK,POKE}{TEXT,DATA}

2018-12-03T09:39:23+00:00

Custom implementations of these ptrace calls are the same as generic
implementations. Drop custom code and use generic.

Signed-off-by: Max Filippov

xtensa: fix coprocessor part of ptrace_{get,set}xregs

2018-11-27T02:37:51+00:00

Layout of coprocessor registers in the elf_xtregs_t and
xtregs_coprocessor_t may be different due to alignment. Thus it is not
always possible to copy data between the xtregs_coprocessor_t structure
and the elf_xtregs_t and get correct values for all registers.
Use a table of offsets and sizes of individual coprocessor register
groups to do coprocessor context copying in the ptrace_getxregs and
ptrace_setxregs.
This fixes incorrect coprocessor register values reading from the user
process by the native gdb on an xtensa core with multiple coprocessors
and registers with high alignment requirements.

Cc: stable@vger.kernel.org
Signed-off-by: Max Filippov

signal/ptrace: Add force_sig_ptrace_errno_trap and use it where needed

2018-01-23T01:07:11+00:00

There are so many places that build struct siginfo by hand that at
least one of them is bound to get it wrong.  A handful of cases in the
kernel arguably did just that when using the errno field of siginfo to
pass no errno values to userspace.  The usage is limited to a single
si_code so at least does not mess up anything else.

Encapsulate this questionable pattern in a helper function so
that the userspace ABI is preserved.

Update all of the places that use this pattern to use the new helper
function.

Signed-off-by: "Eric W. Biederman"

xtensa: use generic tracehooks

2017-05-01T14:00:10+00:00

Use tracehook_report_syscall_{entry,exit} instead of a local copy of it
in do_syscall_trace. Allow tracehook to cancel syscall by returning
invalid syscall number to the system_call function.

Signed-off-by: Max Filippov

xtensa: clean up xtensa/kernel/ptrace.c

2017-05-01T14:00:09+00:00

- make locally-used functions static;
- drop meaningless comments and commented out code;
- fix code style and alignment.

Signed-off-by: Max Filippov