From: Masami Hiramatsu <mhiramat@kernel.org>
To: David Long <dave.long@linaro.org>
Cc: "Daniel Thompson" <daniel.thompson@linaro.org>,
"Catalin Marinas" <catalin.marinas@arm.com>,
"Mark Rutland" <mark.rutland@arm.com>,
"Yang Shi" <yang.shi@linaro.org>,
"Zi Shen Lim" <zlim.lnx@gmail.com>,
"Will Deacon" <will.deacon@arm.com>,
"Andrey Ryabinin" <ryabinin.a.a@gmail.com>,
"yalin wang" <yalin.wang2010@gmail.com>,
"Li Bin" <huawei.libin@huawei.com>,
"Jisheng Zhang" <jszhang@marvell.com>,
"John Blackwood" <john.blackwood@ccur.com>,
"Pratyush Anand" <panand@redhat.com>,
"Huang Shijie" <shijie.huang@arm.com>,
"Dave P Martin" <Dave.Martin@arm.com>,
"Petr Mladek" <pmladek@suse.com>,
"Vladimir Murzin" <Vladimir.Murzin@arm.com>,
"Steve Capper" <steve.capper@linaro.org>,
"Suzuki K Poulose" <suzuki.poulose@arm.com>,
"Marc Zyngier" <marc.zyngier@arm.com>,
"Mark Brown" <broonie@kernel.org>,
"Sandeepa Prabhu" <sandeepa.s.prabhu@gmail.com>,
"William Cohen" <wcohen@redhat.com>,
"Alex Bennée" <alex.bennee@linaro.org>,
"Adam Buchbinder" <adam.buchbinder@gmail.com>,
linux-arm-kernel@lists.infradead.org,
"Ard Biesheuvel" <ard.biesheuvel@linaro.org>,
linux-kernel@vger.kernel.org, "James Morse" <james.morse@arm.com>,
"Masami Hiramatsu" <mhiramat@kernel.org>,
"Andrew Morton" <akpm@linux-foundation.org>,
"Robin Murphy" <robin.murphy@arm.com>,
"Jens Wiklander" <jens.wiklander@linaro.org>,
"Christoffer Dall" <christoffer.dall@linaro.org>,
sparclinux <sparclinux@vger.kernel.org>
Subject: Re: [PATCH v15 04/10] arm64: Kprobes with single stepping support
Date: Tue, 9 Aug 2016 07:49:40 +0900 [thread overview]
Message-ID: <20160809074940.1f33751bc1e6f81b8ee69d44@kernel.org> (raw)
In-Reply-To: <57A89731.20709@linaro.org>
On Mon, 8 Aug 2016 10:29:05 -0400
David Long <dave.long@linaro.org> wrote:
> >> @@ -489,20 +477,15 @@ int __kprobes setjmp_pre_handler(struct kprobe
> >> *p, struct pt_regs *regs)
> >> {
> >> struct jprobe *jp = container_of(p, struct jprobe, kp);
> >> struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
> >> - long stack_ptr = kernel_stack_pointer(regs);
> >>
> >> kcb->jprobe_saved_regs = *regs;
> >> /*
> >> - * As Linus pointed out, gcc assumes that the callee
> >> - * owns the argument space and could overwrite it, e.g.
> >> - * tailcall optimization. So, to be absolutely safe
> >> - * we also save and restore enough stack bytes to cover
> >> - * the argument area.
> >> + * Since we can't be sure where in the stack frame "stacked"
> >> + * pass-by-value arguments are stored we just don't try to
> >> + * duplicate any of the stack.
> > > ...
> >> Do not use jprobes on functions
> >> that
> >> + * use more than 64 bytes (after padding each to an 8 byte boundary)
> >> + * of arguments, or pass individual arguments larger than 16 bytes.
> >
> > I like this wording. So much so that it really would be great to repeat
> > this in the Documentation/. Could this be included in the list of
> > architecture support/restrictions?
> >
>
> Are you thinking specifically of the "5. Kprobes Features and
> Limitations" section in Documentation/kprobes.txt?
OK, That's a good idea :)
If you update the patch for that, please feel free to add my Ack.
Thank you,
--
Masami Hiramatsu <mhiramat@kernel.org>
next prev parent reply other threads:[~2016-08-08 22:49 UTC|newest]
Thread overview: 71+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-07-08 16:35 [PATCH v15 00/10] arm64: Add kernel probes (kprobes) support David Long
2016-07-08 16:35 ` [PATCH v15 01/10] arm64: Add HAVE_REGS_AND_STACK_ACCESS_API feature David Long
2016-07-15 10:57 ` Catalin Marinas
2016-07-15 14:51 ` David Long
2016-07-15 15:13 ` Catalin Marinas
2016-07-15 17:51 ` David Long
2016-07-19 14:17 ` Catalin Marinas
2016-07-08 16:35 ` [PATCH v15 02/10] arm64: Add more test functions to insn.c David Long
2016-07-08 16:35 ` [PATCH v15 03/10] arm64: add conditional instruction simulation support David Long
2016-07-08 16:35 ` [PATCH v15 04/10] arm64: Kprobes with single stepping support David Long
2016-07-20 9:36 ` Marc Zyngier
2016-07-20 11:16 ` Catalin Marinas
2016-07-20 19:08 ` David Long
2016-07-21 8:44 ` Marc Zyngier
2016-07-20 15:49 ` Catalin Marinas
2016-07-21 14:50 ` David Long
2016-07-20 16:09 ` Marc Zyngier
2016-07-20 16:28 ` Catalin Marinas
2016-07-20 16:31 ` Marc Zyngier
2016-07-20 16:46 ` Marc Zyngier
2016-07-20 17:04 ` Catalin Marinas
2016-07-21 16:33 ` David Long
2016-07-21 17:16 ` Catalin Marinas
2016-07-21 17:23 ` Marc Zyngier
2016-07-21 18:33 ` David Long
2016-07-22 10:16 ` Catalin Marinas
2016-07-22 15:51 ` David Long
2016-07-25 17:13 ` Catalin Marinas
2016-07-25 22:27 ` David Long
2016-07-27 11:50 ` Daniel Thompson
2016-07-27 22:13 ` David Long
2016-07-28 14:40 ` Catalin Marinas
2016-07-29 9:01 ` Daniel Thompson
2016-08-04 4:47 ` David Long
2016-08-08 11:13 ` Daniel Thompson
2016-08-08 14:29 ` David Long
2016-08-08 22:49 ` Masami Hiramatsu [this message]
2016-08-09 17:23 ` Catalin Marinas
2016-08-10 20:41 ` David Long
2016-08-08 22:19 ` Masami Hiramatsu
2016-07-26 9:50 ` Daniel Thompson
2016-07-26 16:55 ` Catalin Marinas
2016-07-27 10:01 ` Dave Martin
2016-07-26 17:54 ` Mark Rutland
2016-07-27 11:19 ` Daniel Thompson
2016-07-27 11:38 ` Dave Martin
2016-07-27 11:42 ` Daniel Thompson
2016-07-27 13:38 ` Mark Rutland
2016-07-08 16:35 ` [PATCH v15 05/10] arm64: Blacklist non-kprobe-able symbol David Long
2016-07-08 16:35 ` [PATCH v15 06/10] arm64: Treat all entry code as non-kprobe-able David Long
2016-07-15 16:47 ` Catalin Marinas
2016-07-19 0:53 ` David Long
2016-07-08 16:35 ` [PATCH v15 07/10] arm64: kprobes instruction simulation support David Long
2016-07-10 22:51 ` Paul Gortmaker
2016-07-08 16:35 ` [PATCH v15 08/10] arm64: Add trampoline code for kretprobes David Long
2016-07-19 13:46 ` Catalin Marinas
2016-07-20 18:28 ` David Long
2016-07-08 16:35 ` [PATCH v15 09/10] arm64: Add kernel return probes support (kretprobes) David Long
2016-07-08 16:35 ` [PATCH v15 10/10] kprobes: Add arm64 case in kprobe example module David Long
2016-07-14 16:22 ` [PATCH v15 00/10] arm64: Add kernel probes (kprobes) support Catalin Marinas
2016-07-14 17:09 ` William Cohen
2016-07-15 7:50 ` Catalin Marinas
2016-07-15 8:01 ` Marc Zyngier
2016-07-15 8:59 ` Alex Bennée
2016-07-15 9:04 ` Marc Zyngier
2016-07-15 9:53 ` Marc Zyngier
2016-07-14 17:56 ` David Long
2016-07-19 13:57 ` Catalin Marinas
2016-07-19 14:01 ` David Long
2016-07-19 18:27 ` Catalin Marinas
2016-07-19 19:38 ` David Long
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20160809074940.1f33751bc1e6f81b8ee69d44@kernel.org \
--to=mhiramat@kernel.org \
--cc=Dave.Martin@arm.com \
--cc=Vladimir.Murzin@arm.com \
--cc=adam.buchbinder@gmail.com \
--cc=akpm@linux-foundation.org \
--cc=alex.bennee@linaro.org \
--cc=ard.biesheuvel@linaro.org \
--cc=broonie@kernel.org \
--cc=catalin.marinas@arm.com \
--cc=christoffer.dall@linaro.org \
--cc=daniel.thompson@linaro.org \
--cc=dave.long@linaro.org \
--cc=huawei.libin@huawei.com \
--cc=james.morse@arm.com \
--cc=jens.wiklander@linaro.org \
--cc=john.blackwood@ccur.com \
--cc=jszhang@marvell.com \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=marc.zyngier@arm.com \
--cc=mark.rutland@arm.com \
--cc=panand@redhat.com \
--cc=pmladek@suse.com \
--cc=robin.murphy@arm.com \
--cc=ryabinin.a.a@gmail.com \
--cc=sandeepa.s.prabhu@gmail.com \
--cc=shijie.huang@arm.com \
--cc=sparclinux@vger.kernel.org \
--cc=steve.capper@linaro.org \
--cc=suzuki.poulose@arm.com \
--cc=wcohen@redhat.com \
--cc=will.deacon@arm.com \
--cc=yalin.wang2010@gmail.com \
--cc=yang.shi@linaro.org \
--cc=zlim.lnx@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).