Re: [2.6.25-rc3 regression] sysctl table check failed: /kernel/vsyscall64

[Thomas Gleixner <tglx@linutronix.de>]

On Wed, 27 Feb 2008, Pavel Emelyanov wrote:

> Frans Pop wrote:
> > Just tried 2.6.25-rc3 and got the error below. Boot continued normally.
> > Error was not present in rc2.
> > 
> > System is x86_64, dual core Pentium D, Debian unstable.
> > 
> > Cheers,
> > FJP
> > 
> > P.S. Yes, I do have VirtualBox working under 2.6.25 now ;-)
> 
> That's due to commit ce28b9 x86: fix vsyscall wreckage
> 
> The proc_handler initialization is simply dropped for this table,
> but AFAIS from the commit comment this was done simply to disable
> the vsyscall_gtod_data.sysctl_enabled tuning. Did I miss something?

No. I noticed my stupidity already. Patch below is queued for Linus.

Thanks,
	tglx

------------>
Subject: x86: restore vsyscall64 prochandler
From: Thomas Gleixner <tglx@linutronix.de>
Date: Wed, 27 Feb 2008 09:39:52 +0100

commit ce28b9864b853803320c3f1d8de1b81aa4120b14
       x86: fix vsyscall wreckage

removed the prochandler completely. This triggers:
sysctl table check failed: /kernel/vsyscall64  No proc_handler

Restore the sane part of the proc handler.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
 arch/x86/kernel/vsyscall_64.c |   11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

Index: linux-2.6/arch/x86/kernel/vsyscall_64.c
===================================================================
--- linux-2.6.orig/arch/x86/kernel/vsyscall_64.c
+++ linux-2.6/arch/x86/kernel/vsyscall_64.c
@@ -222,10 +222,19 @@ long __vsyscall(3) venosys_1(void)
 }
 
 #ifdef CONFIG_SYSCTL
+
+static int
+vsyscall_sysctl_change(ctl_table *ctl, int write, struct file * filp,
+		       void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+	return proc_dointvec(ctl, write, filp, buffer, lenp, ppos);
+}
+
 static ctl_table kernel_table2[] = {
 	{ .procname = "vsyscall64",
 	  .data = &vsyscall_gtod_data.sysctl_enabled, .maxlen = sizeof(int),
-	  .mode = 0644 },
+	  .mode = 0644,
+	  .proc_handler = vsyscall_sysctl_change },
 	{}
 };