[RFC PATCH -tip v5 00/27] kprobes: Cleanup jprobe implementation
From: Masami Hiramatsu
Date: Mon Jun 04 2018 - 11:49:04 EST
Hello,
Since we decided to remove jprobe from kernel last year,
its APIs are disabled and we worked on moving in-kernel
jprobe users to kprobes or trace-events. And now no jprobe
users are here anymore.
This is the 5th version of the series for removing jprobe.
Previous version is here:
https://lkml.org/lkml/2018/5/28/71
In this version, I just fixed [24/27] patch to remove unneeded
preempt_disable/enabel and cleanup current_kprobe in
kprobe_ftrace_handler on arch/powerpc too.
Also, I added arch-specific mailing lists to Cc but optimize
Cc list for each patch. So only arch related patches are sent
to each mailing list.
BTW, in the previous version I missed RFC on the patch tag...
This time I added it.
Series structure
=====
Basically this series introduces 3 major changes;
- Remove jprobe implementation ([2/27] - [12/27])
- Remove break_handler() related code ([13/27] - [23/27])
This should be done after (or with) removing jprobe
because break_handler is only used by jprobe.
(I'm not so sure, should I merge above patches into one
arch-wide patch as next one does?)
- Clean current_kprobe and enable preempt if pre_handler()
returns !0 ([24/27] and [25/27]<- x86 specific update)
This also depends on above patches because those
current_kprobe and preemption are expected to be adjusted
by jprobe implementation via break_handler.
And some minor changes;
- Document cleanup and update ([1/27], [26/27])
And finally remove jprobe stub APIs and break_handler
from kprobes.h ([27/27]). Of course this depends on
above patches.
Since removing jprobes and break_handler related code
involve archtecture specific changes in some archs,
I splitted it for each arch. But "clean current_kprobe and
enable preempt if pre_handler() returns !0" patch modifies
all architectures, since it changes expected kprobe
handler behavior. I think this would be better done in
one patch for consistency.
Result
=====
I've tested it with kprobe sanity test on x86-64, and arm64
but for other archs, I just did cross-build test.
With this series, we finally cleanup all jprobe code
and break_handler as below.
$ git grep -wi break_handler | wc -l
0
$ git grep -wi jprobe | wc -l
0
Actually, there is one place where mentioning jprobe,
Documentation/kprobes.txt explains jprobe is deprecated
and how to migrate jprobe user to ftrace or kprobe.
I didn't remove it because it might be useful for
some users.
Thank you,
---
Masami Hiramatsu (27):
Documentation/kprobes: Fix to remove remaining jprobe
kprobes: Remove jprobe API implementation
kprobes/x86: Remove jprobe implementation
ARC: kprobes: Remove jprobe implementation
ARM: kprobes: Remove jprobe arm implementation
arm64: kprobes: Remove jprobe implementation
powerpc/kprobes: Remove jprobe powerpc implementation
ia64: kprobes: Remove jprobe implementation
MIPS: kprobes: Remove jprobe implementation
s390/kprobes: Remove jprobe implementation
sh: kprobes: Remove jprobe implementation
sparc64: kprobes: Remove jprobe implementation
kprobes: Don't check the ->break_handler() in generic kprobes code
kprobes/x86: Don't call ->break_handler() in x86 kprobes
ARC: kprobes: Don't call the ->break_handler() in ARC kprobes code
ARM: kprobes: Don't call the ->break_handler() in arm kprobes code
arm64: kprobes: Don't call the ->break_handler() in arm kprobes code
powerpc/kprobes: Don't call the ->break_handler() in arm kprobes code
ia64: kprobes: Don't call the ->break_handler() in ia64 kprobes code
MIPS: kprobes: Don't call the ->break_handler() in MIPS kprobes code
s390/kprobes: Don't call the ->break_handler() in s390 kprobes code
sh: kprobes: Don't call the ->break_handler() in SH kprobes code
sparc64: kprobes: Don't call the ->break_handler() in sparc64 kprobes code
bpf: error-inject: kprobes: Clear current_kprobe and enable preempt in kprobe
kprobes/x86: Do not disable preempt on int3 path
Documentation: kprobes: Add how to change the execution path
kprobes: Remove jprobe stub API
Documentation/kprobes.txt | 35 +++++-
arch/arc/include/asm/kprobes.h | 2
arch/arc/kernel/kprobes.c | 50 +--------
arch/arm/include/asm/kprobes.h | 2
arch/arm/include/asm/probes.h | 1
arch/arm/probes/kprobes/core.c | 135 +-----------------------
arch/arm64/include/asm/kprobes.h | 1
arch/arm64/kernel/probes/kprobes.c | 86 +--------------
arch/ia64/include/asm/kprobes.h | 2
arch/ia64/include/uapi/asm/break.h | 1
arch/ia64/kernel/Makefile | 2
arch/ia64/kernel/jprobes.S | 90 ----------------
arch/ia64/kernel/kprobes.c | 93 +----------------
arch/mips/include/asm/kprobes.h | 13 --
arch/mips/kernel/kprobes.c | 70 ++----------
arch/powerpc/include/asm/kprobes.h | 12 --
arch/powerpc/kernel/kprobes-ftrace.c | 46 ++------
arch/powerpc/kernel/kprobes.c | 92 +++-------------
arch/powerpc/kernel/trace/ftrace_64_mprofile.S | 39 +------
arch/s390/include/asm/kprobes.h | 2
arch/s390/kernel/kprobes.c | 86 +--------------
arch/sh/include/asm/kprobes.h | 4 -
arch/sh/kernel/kprobes.c | 72 +------------
arch/sparc/include/asm/kprobes.h | 1
arch/sparc/kernel/kprobes.c | 65 +-----------
arch/x86/include/asm/kprobes.h | 5 -
arch/x86/kernel/kprobes/common.h | 10 --
arch/x86/kernel/kprobes/core.c | 119 +--------------------
arch/x86/kernel/kprobes/ftrace.c | 31 ++----
arch/x86/kernel/kprobes/opt.c | 1
include/linux/kprobes.h | 53 ---------
kernel/fail_function.c | 3 -
kernel/kprobes.c | 115 +-------------------
kernel/test_kprobes.c | 94 -----------------
kernel/trace/trace_kprobe.c | 11 +-
lib/Kconfig.debug | 2
36 files changed, 131 insertions(+), 1315 deletions(-)
delete mode 100644 arch/ia64/kernel/jprobes.S
--
Masami Hiramatsu (Linaro)