linux-arch.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Masami Hiramatsu <mhiramat@kernel.org>
To: fche@redhat.com (Frank Ch. Eigler)
Cc: peterz@infradead.org, Ingo Molnar <mingo@kernel.org>,
	linux-kernel@vger.kernel.org, Eddy_Wu@trendmicro.com,
	x86@kernel.org, davem@davemloft.net, rostedt@goodmis.org,
	naveen.n.rao@linux.ibm.com, anil.s.keshavamurthy@intel.com,
	linux-arch@vger.kernel.org, cameron@moodycamel.com,
	oleg@redhat.com, will@kernel.org, paulmck@kernel.org,
	systemtap@sourceware.org
Subject: Re: [PATCH v5 00/21] kprobes: Unify kretprobe trampoline handlers and make kretprobe lockless
Date: Tue, 8 Sep 2020 11:55:27 +0900	[thread overview]
Message-ID: <20200908115527.cf8d2b106bf1a9c4416bbc89@kernel.org> (raw)
In-Reply-To: <87eendo51o.fsf@redhat.com>

On Mon, 07 Sep 2020 13:44:19 -0400
fche@redhat.com (Frank Ch. Eigler) wrote:

> Masami Hiramatsu <mhiramat@kernel.org> writes:
> 
> > Sorry, for noticing this point, I Cc'd to systemtap. Is systemtap taking
> > care of spinlock too?
> 
> On PRREMPT_RT configurations, systemtap uses the raw_spinlock_t
> types/functions, to keep its probe handlers as atomic as we can make them.

OK, if the lock is only used in the probe handlers, there should be
no problem. Even if a probe hits in the NMI which happens in another
kprobe handler, the probe does not call its handler (because we don't
support nested kprobes* yet).
But maybe you'll get warnings if you enable the lockdep.

* https://lkml.kernel.org/r/158894789510.14896.13461271606820304664.stgit@devnote2
It seems that we need more work for the nested kprobes.

Thank you,

-- 
Masami Hiramatsu <mhiramat@kernel.org>

  reply	other threads:[~2020-09-08  2:55 UTC|newest]

Thread overview: 51+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-08-29 12:59 [PATCH v5 00/21] kprobes: Unify kretprobe trampoline handlers and make kretprobe lockless Masami Hiramatsu
2020-08-29 13:00 ` [PATCH v5 01/21] kprobes: Add generic kretprobe trampoline handler Masami Hiramatsu
2020-08-29 13:00 ` [PATCH v5 02/21] x86/kprobes: Use " Masami Hiramatsu
2020-08-29 13:00 ` [PATCH v5 03/21] arm: kprobes: " Masami Hiramatsu
2020-08-29 13:00 ` [PATCH v5 04/21] arm64: " Masami Hiramatsu
2020-08-29 13:00 ` [PATCH v5 05/21] arc: " Masami Hiramatsu
2020-08-29 13:00 ` [PATCH v5 06/21] csky: " Masami Hiramatsu
2020-08-29 13:01 ` [PATCH v5 07/21] ia64: " Masami Hiramatsu
2020-08-29 13:01 ` [PATCH v5 08/21] mips: " Masami Hiramatsu
2020-08-29 13:01 ` [PATCH v5 09/21] parisc: " Masami Hiramatsu
2020-08-29 13:01 ` [PATCH v5 10/21] powerpc: " Masami Hiramatsu
2020-08-29 13:02 ` [PATCH v5 11/21] s390: " Masami Hiramatsu
2020-08-29 13:02 ` [PATCH v5 12/21] sh: " Masami Hiramatsu
2020-08-29 13:02 ` [PATCH v5 13/21] sparc: " Masami Hiramatsu
2020-08-29 13:02 ` [PATCH v5 14/21] kprobes: Remove NMI context check Masami Hiramatsu
     [not found]   ` <20201030213831.04e81962@oasis.local.home>
2020-11-02  5:11     ` Masami Hiramatsu
2020-11-02  5:53       ` Masami Hiramatsu
2020-11-02  7:02         ` Masami Hiramatsu
2020-11-02 14:27           ` Steven Rostedt
2020-11-03  5:39             ` Masami Hiramatsu
2020-11-03 16:09               ` Steven Rostedt
2020-11-04  2:08                 ` Masami Hiramatsu
2020-11-04 14:47                   ` Steven Rostedt
2020-11-05  5:15                     ` Masami Hiramatsu
2020-08-29 13:02 ` [PATCH v5 15/21] kprobes: Free kretprobe_instance with rcu callback Masami Hiramatsu
2020-08-29 13:03 ` [PATCH v5 16/21] kprobes: Make local used functions static Masami Hiramatsu
2020-08-29 13:03 ` [PATCH v5 17/21] llist: Add nonatomic __llist_add() and __llist_dell_all() Masami Hiramatsu
2020-10-12 16:24   ` Ingo Molnar
2020-10-14  0:24     ` Masami Hiramatsu
2020-08-29 13:03 ` [PATCH v5 18/21] kprobes: Remove kretprobe hash Masami Hiramatsu
2020-08-29 13:03 ` [PATCH v5 19/21] asm-generic/atomic: Add try_cmpxchg() fallbacks Masami Hiramatsu
2020-10-12 16:25   ` Ingo Molnar
2020-08-29 13:03 ` [PATCH v5 20/21] freelist: Lock less freelist Masami Hiramatsu
2020-08-29 13:03 ` [PATCH v5 21/21] kprobes: Replace rp->free_instance with freelist Masami Hiramatsu
2020-09-01 19:08 ` [PATCH v5 00/21] kprobes: Unify kretprobe trampoline handlers and make kretprobe lockless Peter Zijlstra
2020-09-02  0:37   ` Masami Hiramatsu
2020-09-02  7:02     ` peterz
2020-09-02  8:17       ` Masami Hiramatsu
2020-09-02  9:36         ` peterz
2020-09-02 13:19           ` Masami Hiramatsu
2020-09-02 13:42             ` peterz
2020-09-03  1:39               ` Masami Hiramatsu
2020-09-03  2:02                 ` Masami Hiramatsu
2020-09-07 17:44                   ` Frank Ch. Eigler
2020-09-08  2:55                     ` Masami Hiramatsu [this message]
2020-09-08 10:37                 ` peterz
2020-09-08 11:15                   ` Eddy_Wu
2020-09-08 11:33                     ` peterz
2020-09-08 15:09                   ` Masami Hiramatsu
2020-09-09  5:28                     ` Masami Hiramatsu
2020-09-11  2:32       ` Masami Hiramatsu

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=20200908115527.cf8d2b106bf1a9c4416bbc89@kernel.org \
    --to=mhiramat@kernel.org \
    --cc=Eddy_Wu@trendmicro.com \
    --cc=anil.s.keshavamurthy@intel.com \
    --cc=cameron@moodycamel.com \
    --cc=davem@davemloft.net \
    --cc=fche@redhat.com \
    --cc=linux-arch@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@kernel.org \
    --cc=naveen.n.rao@linux.ibm.com \
    --cc=oleg@redhat.com \
    --cc=paulmck@kernel.org \
    --cc=peterz@infradead.org \
    --cc=rostedt@goodmis.org \
    --cc=systemtap@sourceware.org \
    --cc=will@kernel.org \
    --cc=x86@kernel.org \
    /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).