From: peterz@infradead.org
To: Masami Hiramatsu <mhiramat@kernel.org>
Cc: 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
Subject: Re: [PATCH v4 20/23] [RFC] kprobes: Remove task scan for updating kretprobe_instance
Date: Fri, 28 Aug 2020 17:18:06 +0200 [thread overview]
Message-ID: <20200828151806.GF1362448@hirez.programming.kicks-ass.net> (raw)
In-Reply-To: <20200829001010.7ec1a183c2294f7bd843b153@kernel.org>
On Sat, Aug 29, 2020 at 12:10:10AM +0900, Masami Hiramatsu wrote:
> On Fri, 28 Aug 2020 14:52:36 +0200
> peterz@infradead.org wrote:
> > > synchronize_rcu();
> >
> > This one might help, this means we can do rcu_read_lock() around
> > get_kretprobe() and it's usage. Can we call rp->handler() under RCU?
>
> Yes, as I said above, the get_kretprobe() (and kretprobe handler) must be
> called under preempt-disabled.
Then we don't need the ordering; we'll need READ_ONCE() (or
rcu_derefernce()) to make sure the address dependency works on Alpha.
And a comment/assertion that explains this might not go amiss in
get_kretprobe().
next prev parent reply other threads:[~2020-08-28 15:18 UTC|newest]
Thread overview: 41+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-08-28 12:26 [PATCH v4 00/23] kprobes: Unify kretprobe trampoline handlers and make kretprobe lockless Masami Hiramatsu
2020-08-28 12:26 ` [PATCH v4 01/23] kprobes: Add generic kretprobe trampoline handler Masami Hiramatsu
2020-08-28 12:27 ` [PATCH v4 02/23] x86/kprobes: Use " Masami Hiramatsu
2020-08-28 12:27 ` [PATCH v4 03/23] arm: kprobes: " Masami Hiramatsu
2020-08-28 12:27 ` [PATCH v4 04/23] arm64: " Masami Hiramatsu
2020-08-28 13:31 ` Mark Rutland
2020-08-28 13:37 ` peterz
2020-08-28 13:48 ` Mark Rutland
2020-08-28 13:58 ` Masami Hiramatsu
2020-08-28 12:27 ` [PATCH v4 05/23] arc: " Masami Hiramatsu
2020-08-28 12:27 ` [PATCH v4 06/23] csky: " Masami Hiramatsu
2020-08-28 12:27 ` [PATCH v4 07/23] ia64: " Masami Hiramatsu
2020-08-28 12:28 ` [PATCH v4 08/23] mips: " Masami Hiramatsu
2020-08-28 12:28 ` [PATCH v4 09/23] parisc: " Masami Hiramatsu
2020-08-28 12:28 ` [PATCH v4 10/23] powerpc: " Masami Hiramatsu
2020-08-28 12:28 ` [PATCH v4 11/23] s390: " Masami Hiramatsu
2020-08-28 12:28 ` [PATCH v4 12/23] sh: " Masami Hiramatsu
2020-08-28 12:29 ` [PATCH v4 13/23] sparc: " Masami Hiramatsu
2020-08-28 12:29 ` [PATCH v4 14/23] kprobes: Remove NMI context check Masami Hiramatsu
2020-08-28 12:29 ` [PATCH v4 15/23] kprobes: Free kretprobe_instance with rcu callback Masami Hiramatsu
2020-08-28 12:29 ` [PATCH v4 16/23] kprobes: Make local used functions static Masami Hiramatsu
2020-08-28 12:29 ` [PATCH v4 17/23] llist: Add nonatomic __llist_add() Masami Hiramatsu
2020-08-28 12:29 ` [PATCH v4 18/23] sched: Fix try_invoke_on_locked_down_task() semantics Masami Hiramatsu
2020-08-29 2:01 ` Masami Hiramatsu
2020-08-29 7:30 ` peterz
2020-08-29 17:31 ` Paul E. McKenney
2020-08-28 12:30 ` [PATCH v4 19/23] kprobes: Remove kretprobe hash Masami Hiramatsu
2020-08-28 18:37 ` Masami Hiramatsu
2020-08-28 19:02 ` peterz
2020-08-28 19:32 ` Eddy_Wu
2020-08-28 20:29 ` Peter Zijlstra
2020-08-29 1:23 ` Masami Hiramatsu
2020-08-28 12:30 ` [PATCH v4 20/23] [RFC] kprobes: Remove task scan for updating kretprobe_instance Masami Hiramatsu
2020-08-28 12:52 ` peterz
2020-08-28 15:10 ` Masami Hiramatsu
2020-08-28 15:18 ` peterz [this message]
2020-08-28 16:01 ` Masami Hiramatsu
2020-08-28 12:30 ` [PATCH v4 21/23] asm-generic/atomic: Add try_cmpxchg() fallbacks Masami Hiramatsu
2020-08-28 12:30 ` [PATCH v4 22/23] freelist: Lock less freelist Masami Hiramatsu
2020-08-28 12:30 ` [PATCH v4 23/23] kprobes: Replace rp->free_instance with freelist Masami Hiramatsu
2020-08-28 12:37 ` [PATCH v4 00/23] kprobes: Unify kretprobe trampoline handlers and make kretprobe lockless Masami Hiramatsu
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