From: Thomas Gleixner <tglx@linutronix.de>
Date: Fri, 1 May 2009 18:59:25 +0000 (+0200)
Subject: x86: initialize io_bitmap_base on 32bit
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=f9a196b8dceba3c1e5fe885b81e45043ad7c60fc;p=linux-beck.git

x86: initialize io_bitmap_base on 32bit

commit db949bba3c7cf2e664ac12e237c6d4c914f0c69d (x86-32: use non-lazy
io bitmap context switching) broke ioperm for 32bit because it removed
the lazy initialization of io_bitmap_base and did not set it to the
real bitmap offset.

[ Impact: fix non-working sys_ioperm() on 32-bit kernels ]

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---

diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index c4f667896c28..c1caefc82e62 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -1203,6 +1203,8 @@ void __cpuinit cpu_init(void)
 	load_TR_desc();
 	load_LDT(&init_mm.context);
 
+	t->x86_tss.io_bitmap_base = offsetof(struct tss_struct, io_bitmap);
+
 #ifdef CONFIG_DOUBLEFAULT
 	/* Set up doublefault TSS pointer in the GDT */
 	__set_tss_desc(cpu, GDT_ENTRY_DOUBLEFAULT_TSS, &doublefault_tss);