From: tip-bot for Masami Hiramatsu <tipbot@zytor.com>
To: linux-tip-commits@vger.kernel.org
Cc: tglx@linutronix.de, oleg@redhat.com,
torvalds@linux-foundation.org, namit@vmware.com,
mingo@kernel.org, alexei.starovoitov@gmail.com, hpa@zytor.com,
mhiramat@kernel.org, peterz@infradead.org,
linux-kernel@vger.kernel.org, luto@kernel.org,
stable@vger.kernel.org, bp@alien8.de
Subject: [tip:perf/core] kprobes/x86: Use preempt_enable() in optimized_callback()
Date: Sun, 21 Oct 2018 18:33:51 -0700 [thread overview]
Message-ID: <tip-2e62024c265aa69315ed02835623740030435380@git.kernel.org> (raw)
In-Reply-To: <154002887331.7627.10194920925792947001.stgit@devbox>
Commit-ID: 2e62024c265aa69315ed02835623740030435380
Gitweb: https://git.kernel.org/tip/2e62024c265aa69315ed02835623740030435380
Author: Masami Hiramatsu <mhiramat@kernel.org>
AuthorDate: Sat, 20 Oct 2018 18:47:53 +0900
Committer: Ingo Molnar <mingo@kernel.org>
CommitDate: Mon, 22 Oct 2018 03:31:01 +0200
kprobes/x86: Use preempt_enable() in optimized_callback()
The following commit:
a19b2e3d7839 ("kprobes/x86: Remove IRQ disabling from ftrace-based/optimized kprobes”)
removed local_irq_save/restore() from optimized_callback(), the handler
might be interrupted by the rescheduling interrupt and might be
rescheduled - so we must not use the preempt_enable_no_resched() macro.
Use preempt_enable() instead, to not lose preemption events.
[ mingo: Improved the changelog. ]
Reported-by: Nadav Amit <namit@vmware.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <stable@vger.kernel.org>
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dwmw@amazon.co.uk
Fixes: a19b2e3d7839 ("kprobes/x86: Remove IRQ disabling from ftrace-based/optimized kprobes”)
Link: http://lkml.kernel.org/r/154002887331.7627.10194920925792947001.stgit@devbox
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
arch/x86/kernel/kprobes/opt.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/kernel/kprobes/opt.c b/arch/x86/kernel/kprobes/opt.c
index eaf02f2e7300..40b16b270656 100644
--- a/arch/x86/kernel/kprobes/opt.c
+++ b/arch/x86/kernel/kprobes/opt.c
@@ -179,7 +179,7 @@ optimized_callback(struct optimized_kprobe *op, struct pt_regs *regs)
opt_pre_handler(&op->kp, regs);
__this_cpu_write(current_kprobe, NULL);
}
- preempt_enable_no_resched();
+ preempt_enable();
}
NOKPROBE_SYMBOL(optimized_callback);
prev parent reply other threads:[~2018-10-22 1:34 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-10-20 9:47 [PATCH -tip] kprobes/x86: Use preempt_enable() in optimized_callback() Masami Hiramatsu
2018-10-21 20:42 ` Peter Zijlstra
2018-10-22 1:33 ` tip-bot for Masami Hiramatsu [this message]
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=tip-2e62024c265aa69315ed02835623740030435380@git.kernel.org \
--to=tipbot@zytor.com \
--cc=alexei.starovoitov@gmail.com \
--cc=bp@alien8.de \
--cc=hpa@zytor.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-tip-commits@vger.kernel.org \
--cc=luto@kernel.org \
--cc=mhiramat@kernel.org \
--cc=mingo@kernel.org \
--cc=namit@vmware.com \
--cc=oleg@redhat.com \
--cc=peterz@infradead.org \
--cc=stable@vger.kernel.org \
--cc=tglx@linutronix.de \
--cc=torvalds@linux-foundation.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).