linux-kernel - Re: [PATCH 0/11] LTTng-core (basic tracing infrastructure) 0.5.108

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Sun, 17 Sep 2006 10:13:56 +0000
From:	Frederik Deweerdt <deweerdt@...e.fr>
To:	Ingo Molnar <mingo@...e.hu>
Cc:	Mathieu Desnoyers <mathieu.desnoyers@...ymtl.ca>,
	Jes Sorensen <jes@....com>,
	Roman Zippel <zippel@...ux-m68k.org>,
	Andrew Morton <akpm@...l.org>, tglx@...utronix.de,
	karim@...rsys.com, Paul Mundt <lethal@...ux-sh.org>,
	linux-kernel@...r.kernel.org,
	Christoph Hellwig <hch@...radead.org>,
	Ingo Molnar <mingo@...hat.com>,
	Greg Kroah-Hartman <gregkh@...e.de>,
	Tom Zanussi <zanussi@...ibm.com>, ltt-dev@...fik.org,
	Michel Dagenais <michel.dagenais@...ymtl.ca>
Subject: Re: [PATCH 0/11] LTTng-core (basic tracing infrastructure) 0.5.108

On Sat, Sep 16, 2006 at 09:37:45PM +0200, Ingo Molnar wrote:
> --------------->
> Subject: [patch] kprobes: speed INT3 trap handling up on i386
> From: Ingo Molnar <mingo@...e.hu>
> 
> speed up kprobes trap handling by special-casing kernel-space
> INT3 traps (which do not occur otherwise) and doing a kprobes
> handler check - instead of redirecting over the i386-die-notifier
> chain.
> 
Hi Ingo,

Not that it would make any difference to the actual kprobe performance,
but I think that not using the die-notifier chain makes the DIE_INT3
handling in kprobe_exceptions_notify() useless.

Regards,
Frederik


Signed-off-by: Frederik Deweerdt <frederik.deweerdt@...il.com>

diff --git a/arch/i386/kernel/kprobes.c b/arch/i386/kernel/kprobes.c
index afe6505..90787ff 100644
--- a/arch/i386/kernel/kprobes.c
+++ b/arch/i386/kernel/kprobes.c
@@ -652,10 +652,6 @@ int __kprobes kprobe_exceptions_notify(s
 		return ret;
 
 	switch (val) {
-	case DIE_INT3:
-		if (kprobe_handler(args->regs))
-			ret = NOTIFY_STOP;
-		break;
 	case DIE_DEBUG:
 		if (post_kprobe_handler(args->regs))
 			ret = NOTIFY_STOP;
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/