Re: [PATCH v8] rethook: add riscv rethook implementation

From: binglei wang
Date: Sat Oct 22 2022 - 13:16:01 EST


Hi Conor,
I would appreciate if you can send the patch for me this time !
As keen as mustard i am to see the patch applied and merged if there
is no something unsuitable.

Binglei Wang
Best wishes.



2022-10-18 22:22 GMT+08:00, Conor Dooley <conor.dooley@xxxxxxxxxxxxx>:
> On Tue, Oct 18, 2022 at 10:08:55PM +0800, binglei wang wrote:
>> Hi Conor:
>> Thank you for your help to check the merging process for this patch.
>>
>> > Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
>> > -- links below jump to the message on this page --
>> > [not found] <20220930081357.651914-1-l3b2w1@xxxxxxxxx>
>> I have no idea what this means, I guess maybe the way i sended the
>> patch was not right.
>>
>> I found the patch on the lore in this url, is this helpful ?
>> https://lore.kernel.org/lkml/20221002181035.490ad0155d741e39faa29716@xxxxxxxxxx/
>
> Hmm, looks like your patch made it to lkml itself but got rejected by
> linux-riscv which is hosted by infradead. It's missing here:
> https://lore.kernel.org/linux-riscv/CAJ3C4Kwj0yYS5JCPw=g0X9qiQhw04iKy_cTjc0x8iWdy0ay7bg@xxxxxxxxxxxxxx/T/#t
>
>>
>> > I'm not really sure what's happened there.. I can only see your v1 and
>> > your v4 on lore/patchwork.
>> I find all my commits from v1 to v8 in this addr
>> https://lore.kernel.org/lkml/?q=l3b2w1
>>
>> Should I resend the patch as a last resort ?
>
> Eh, I guess you could try (and CC patches@xxxxxxxxxxxxxxx). I'm not sure
> if that'll help at all though.. At worst, if that doesn't work I could
> possibly send the patches for you. Or if you think you may end up doing
> more upstream work you could always apply for an @linux.dev account?
> See https://korg.docs.kernel.org/linuxdev.html for more information on
> that.
>
>>
>> Binglei Wang
>> Best wishes.
>>
>> Conor Dooley <conor@xxxxxxxxxx> 于2022年10月17日周一 22:58写道:
>> >
>> > On Mon, Oct 17, 2022 at 10:31:28PM +0800, binglei wang wrote:
>> > > Hi Conor,
>> > > could you please help me to push forward merging process of this
>> > > patch
>> > > into the 6.1 ? Thank you!
>> >
>> > Hey Binglei,
>> > Unfortunately it is too late for v6.1 (the merge window closed on
>> > Sunday, Palmer sent his second PR on Friday) but I don't see why this
>> > should not be picked for v6.2. I tried last week & again just now to
>> > check the status of this patch on patchwork but I cannot find it there.
>> > Similarly, the patch does not appear on lore:
>> > https://lore.kernel.org/linux-riscv/CAJ3C4KzyAR7dKYFBKHzFEXr-dzr-JMGRFVx+dybMhRPy0uHUgA@xxxxxxxxxxxxxx/T/#t
>> > Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
>> > -- links below jump to the message on this page --
>> > [not found] <20220930081357.651914-1-l3b2w1@xxxxxxxxx>
>> > 2022-10-02 9:10 ` [PATCH v8] rethook: add riscv rethook implementation
>> > Masami Hiramatsu
>> > 2022-10-02 16:39 ` Conor Dooley
>> > 2022-10-17 14:31 ` binglei wang
>> >
>> > I'm not really sure what's happened there.. I can only see your v1 and
>> > your v4 on lore/patchwork. Maybe take a look if you changed anything
>> > between versions & try resending as v9?
>> >
>> > HTH,
>> > Conor.
>> >
>> > >
>> > > Binglei Wang
>> > > Best wishes.
>> > >
>> > >
>> > > On 2022-10-03 00:39, Conor Dooley wrote:
>> > > > Hey Binglei,
>> > > > I am not qualified to give you an actual R-b on this patch, but I
>> > > > see
>> > > > you did get one from Masami who very much is!
>> > > >
>> > > > That said, the patch looks a lot better (and much simpler!) now.
>> > > > Thanks
>> > > > for sticking with it despite the initial issues with your email
>> > > > setup
>> > > > and the submission process.
>> > > >
>> > > > Thanks,
>> > > > Conor.
>> > > >
>> > > > On Fri, Sep 30, 2022 at 04:13:57PM +0800, Binglei Wang wrote:
>> > > >> From: Binglei Wang <l3b2w1@xxxxxxxxx>
>> > > >>
>> > > >> Implement the kretprobes on riscv arch by using rethook machenism
>> > > >> which abstracts general kretprobe info into a struct rethook_node
>> > > >> to be embedded in the struct kretprobe_instance.
>> > > >>
>> > > >> Signed-off-by: Binglei Wang <l3b2w1@xxxxxxxxx>
>> > > >> ---
>> > > >>
>> > > >> Notes:
>> > > >> v8: Add the omitted rethook.h
>> > > >> v7: Add the changelog.
>> > > >> v6: Remove the kretprobes trampoline.
>> > > >> v5: Trt to fix robot compiling error and warnings.
>> > > >> v4: Add patch version number.
>> > > >> v3: Trt to fix robot compiling error and warnings.
>> > > >> v2: Add comit log to explain reasons behind changes.
>> > > >> Use my personal email instead of work email
>> > > >> to avoid the attachments of company informaton.
>> > > >> Make the kprobes_trampoline.S code to be shared.
>> > > >> v1: Add riscv rethook implementation.
>> > > >>
>> > > >> arch/riscv/Kconfig | 1 +
>> > > >> arch/riscv/include/asm/kprobes.h | 2 --
>> > > >> arch/riscv/kernel/probes/Makefile | 2 +-
>> > > >> arch/riscv/kernel/probes/kprobes.c | 13 ---------
>> > > >> arch/riscv/kernel/probes/rethook.c | 27
>> > > >> +++++++++++++++++++
>> > > >> arch/riscv/kernel/probes/rethook.h | 8 ++++++
>> > > >> ...obes_trampoline.S => rethook_trampoline.S} | 6 ++---
>> > > >> 7 files changed, 40 insertions(+), 19 deletions(-)
>> > > >> create mode 100644 arch/riscv/kernel/probes/rethook.c
>> > > >> create mode 100644 arch/riscv/kernel/probes/rethook.h
>> > > >> rename arch/riscv/kernel/probes/{kprobes_trampoline.S =>
>> > > >> rethook_trampoline.S} (94%)
>> > > >>
>> > > >> diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
>> > > >> index 59d18881f..bfb66cdc5 100644
>> > > >> --- a/arch/riscv/Kconfig
>> > > >> +++ b/arch/riscv/Kconfig
>> > > >> @@ -97,6 +97,7 @@ config RISCV
>> > > >> select HAVE_KPROBES if !XIP_KERNEL
>> > > >> select HAVE_KPROBES_ON_FTRACE if !XIP_KERNEL
>> > > >> select HAVE_KRETPROBES if !XIP_KERNEL
>> > > >> + select HAVE_RETHOOK if !XIP_KERNEL
>> > > >> select HAVE_MOVE_PMD
>> > > >> select HAVE_MOVE_PUD
>> > > >> select HAVE_PCI
>> > > >> diff --git a/arch/riscv/include/asm/kprobes.h
>> > > >> b/arch/riscv/include/asm/kprobes.h
>> > > >> index 217ef89f2..e7882ccb0 100644
>> > > >> --- a/arch/riscv/include/asm/kprobes.h
>> > > >> +++ b/arch/riscv/include/asm/kprobes.h
>> > > >> @@ -40,8 +40,6 @@ void arch_remove_kprobe(struct kprobe *p);
>> > > >> int kprobe_fault_handler(struct pt_regs *regs, unsigned int
>> > > >> trapnr);
>> > > >> bool kprobe_breakpoint_handler(struct pt_regs *regs);
>> > > >> bool kprobe_single_step_handler(struct pt_regs *regs);
>> > > >> -void __kretprobe_trampoline(void);
>> > > >> -void __kprobes *trampoline_probe_handler(struct pt_regs *regs);
>> > > >>
>> > > >> #endif /* CONFIG_KPROBES */
>> > > >> #endif /* _ASM_RISCV_KPROBES_H */
>> > > >> diff --git a/arch/riscv/kernel/probes/Makefile
>> > > >> b/arch/riscv/kernel/probes/Makefile
>> > > >> index 7f0840dcc..c40139e9c 100644
>> > > >> --- a/arch/riscv/kernel/probes/Makefile
>> > > >> +++ b/arch/riscv/kernel/probes/Makefile
>> > > >> @@ -1,6 +1,6 @@
>> > > >> # SPDX-License-Identifier: GPL-2.0
>> > > >> obj-$(CONFIG_KPROBES) += kprobes.o decode-insn.o
>> > > >> simulate-insn.o
>> > > >> -obj-$(CONFIG_KPROBES) += kprobes_trampoline.o
>> > > >> +obj-$(CONFIG_RETHOOK) += rethook.o
>> > > >> rethook_trampoline.o
>> > > >> obj-$(CONFIG_KPROBES_ON_FTRACE) += ftrace.o
>> > > >> obj-$(CONFIG_UPROBES) += uprobes.o decode-insn.o
>> > > >> simulate-insn.o
>> > > >> CFLAGS_REMOVE_simulate-insn.o = $(CC_FLAGS_FTRACE)
>> > > >> diff --git a/arch/riscv/kernel/probes/kprobes.c
>> > > >> b/arch/riscv/kernel/probes/kprobes.c
>> > > >> index e6e950b7c..f21592d20 100644
>> > > >> --- a/arch/riscv/kernel/probes/kprobes.c
>> > > >> +++ b/arch/riscv/kernel/probes/kprobes.c
>> > > >> @@ -345,19 +345,6 @@ int __init
>> > > >> arch_populate_kprobe_blacklist(void)
>> > > >> return ret;
>> > > >> }
>> > > >>
>> > > >> -void __kprobes __used *trampoline_probe_handler(struct pt_regs
>> > > >> *regs)
>> > > >> -{
>> > > >> - return (void *)kretprobe_trampoline_handler(regs, NULL);
>> > > >> -}
>> > > >> -
>> > > >> -void __kprobes arch_prepare_kretprobe(struct kretprobe_instance
>> > > >> *ri,
>> > > >> - struct pt_regs *regs)
>> > > >> -{
>> > > >> - ri->ret_addr = (kprobe_opcode_t *)regs->ra;
>> > > >> - ri->fp = NULL;
>> > > >> - regs->ra = (unsigned long) &__kretprobe_trampoline;
>> > > >> -}
>> > > >> -
>> > > >> int __kprobes arch_trampoline_kprobe(struct kprobe *p)
>> > > >> {
>> > > >> return 0;
>> > > >> diff --git a/arch/riscv/kernel/probes/rethook.c
>> > > >> b/arch/riscv/kernel/probes/rethook.c
>> > > >> new file mode 100644
>> > > >> index 000000000..cbd0da059
>> > > >> --- /dev/null
>> > > >> +++ b/arch/riscv/kernel/probes/rethook.c
>> > > >> @@ -0,0 +1,27 @@
>> > > >> +// SPDX-License-Identifier: GPL-2.0-only
>> > > >> +/*
>> > > >> + * Generic return hook for riscv.
>> > > >> + */
>> > > >> +
>> > > >> +#include <linux/kprobes.h>
>> > > >> +#include <linux/rethook.h>
>> > > >> +#include "rethook.h"
>> > > >> +
>> > > >> +/* This is called from arch_rethook_trampoline() */
>> > > >> +unsigned long __used arch_rethook_trampoline_callback(struct
>> > > >> pt_regs *regs)
>> > > >> +{
>> > > >> + return rethook_trampoline_handler(regs, regs->s0);
>> > > >> +}
>> > > >> +NOKPROBE_SYMBOL(arch_rethook_trampoline_callback);
>> > > >> +
>> > > >> +
>> > > >> +void arch_rethook_prepare(struct rethook_node *rhn, struct pt_regs
>> > > >> *regs, bool mcount)
>> > > >> +{
>> > > >> + rhn->ret_addr = regs->ra;
>> > > >> + rhn->frame = regs->s0;
>> > > >> +
>> > > >> + /* replace return addr with trampoline */
>> > > >> + regs->ra = (unsigned long)arch_rethook_trampoline;
>> > > >> +}
>> > > >> +NOKPROBE_SYMBOL(arch_rethook_prepare);
>> > > >> +
>> > > >> diff --git a/arch/riscv/kernel/probes/rethook.h
>> > > >> b/arch/riscv/kernel/probes/rethook.h
>> > > >> new file mode 100644
>> > > >> index 000000000..cc573d701
>> > > >> --- /dev/null
>> > > >> +++ b/arch/riscv/kernel/probes/rethook.h
>> > > >> @@ -0,0 +1,8 @@
>> > > >> +// SPDX-License-Identifier: GPL-2.0-only
>> > > >> +#ifndef __RISCV_RETHOOK_H
>> > > >> +#define __RISCV_RETHOOK_H
>> > > >> +
>> > > >> +unsigned long arch_rethook_trampoline_callback(struct pt_regs
>> > > >> *regs);
>> > > >> +void arch_rethook_prepare(struct rethook_node *rhn, struct pt_regs
>> > > >> *regs, bool mcount);
>> > > >> +
>> > > >> +#endif
>> > > >> diff --git a/arch/riscv/kernel/probes/kprobes_trampoline.S
>> > > >> b/arch/riscv/kernel/probes/rethook_trampoline.S
>> > > >> similarity index 94%
>> > > >> rename from arch/riscv/kernel/probes/kprobes_trampoline.S
>> > > >> rename to arch/riscv/kernel/probes/rethook_trampoline.S
>> > > >> index 7bdb09ded..21bac92a1 100644
>> > > >> --- a/arch/riscv/kernel/probes/kprobes_trampoline.S
>> > > >> +++ b/arch/riscv/kernel/probes/rethook_trampoline.S
>> > > >> @@ -75,13 +75,13 @@
>> > > >> REG_L x31, PT_T6(sp)
>> > > >> .endm
>> > > >>
>> > > >> -ENTRY(__kretprobe_trampoline)
>> > > >> +ENTRY(arch_rethook_trampoline)
>> > > >> addi sp, sp, -(PT_SIZE_ON_STACK)
>> > > >> save_all_base_regs
>> > > >>
>> > > >> move a0, sp /* pt_regs */
>> > > >>
>> > > >> - call trampoline_probe_handler
>> > > >> + call arch_rethook_trampoline_callback
>> > > >>
>> > > >> /* use the result as the return-address */
>> > > >> move ra, a0
>> > > >> @@ -90,4 +90,4 @@ ENTRY(__kretprobe_trampoline)
>> > > >> addi sp, sp, PT_SIZE_ON_STACK
>> > > >>
>> > > >> ret
>> > > >> -ENDPROC(__kretprobe_trampoline)
>> > > >> +ENDPROC(arch_rethook_trampoline)
>> > > >> --
>> > > >> 2.27.0
>> > > >>
>> > >
>> > > _______________________________________________
>> > > linux-riscv mailing list
>> > > linux-riscv@xxxxxxxxxxxxxxxxxxx
>> > > http://lists.infradead.org/mailman/listinfo/linux-riscv
>> > >
>