cr4 is a 32-bit register, so casting the mask to an unsigned char is wrong,
as it clears more than the PGE bit.
Signed-off-by: Brian Gerst <bgerst@didntduck.org>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
        /*  Save value of CR4 and clear Page Global Enable (bit 7)  */
        if ( cpu_has_pge ) {
                cr4 = read_cr4();
-               write_cr4(cr4 & (unsigned char) ~(1 << 7));
+               write_cr4(cr4 & ~X86_CR4_PGE);
        }
 
        /*  Disable and flush caches. Note that wbinvd flushes the TLBs as
 
                /*  Save value of CR4 and clear Page Global Enable (bit 7)  */
                if ( cpu_has_pge ) {
                        ctxt->cr4val = read_cr4();
-                       write_cr4(ctxt->cr4val & (unsigned char) ~(1 << 7));
+                       write_cr4(ctxt->cr4val & ~X86_CR4_PGE);
                }
 
                /*  Disable and flush caches. Note that wbinvd flushes the TLBs as