From mboxrd@z Thu Jan  1 00:00:00 1970
From: Samuel Thibault <samuel.thibault@eu.citrix.com>
Subject: [PATCH] minios: fix gnttab allocation boundary
Date: Tue, 17 Jun 2008 17:54:51 +0100
Message-ID: <20080617165451.GI5994@implementation.uk.xensource.com>
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minios: fix gnttab allocation boundary

The gnttab_sem is already fed during initialization's put_free_entry
loop.

Signed-off-by: Samuel Thibault <samuel.thibault@eu.citrix.com>

diff -r 78f90b0f707f extras/mini-os/gnttab.c
--- a/extras/mini-os/gnttab.c	Tue Jun 17 14:45:18 2008 +0100
+++ b/extras/mini-os/gnttab.c	Tue Jun 17 17:53:51 2008 +0100
@@ -35,7 +35,7 @@
 #ifdef GNT_DEBUG
 static char inuse[NR_GRANT_ENTRIES];
 #endif
-static __DECLARE_SEMAPHORE_GENERIC(gnttab_sem, NR_GRANT_ENTRIES);
+static __DECLARE_SEMAPHORE_GENERIC(gnttab_sem, 0);
 
 static void
 put_free_entry(grant_ref_t ref)
@@ -60,6 +60,7 @@
     down(&gnttab_sem);
     local_irq_save(flags);
     ref = gnttab_list[0];
+    BUG_ON(ref < NR_RESERVED_ENTRIES || ref >= NR_GRANT_ENTRIES);
     gnttab_list[0] = gnttab_list[ref];
 #ifdef GNT_DEBUG
     BUG_ON(inuse[ref]);