When compiling a Linux 2.6 kernel using gcc 3.3.3, gcc was able to inline the function do_test_wp_bit().  This causes i386 kernels to panic on boot, since the exception handler doesn't work properly.

The fix is straightforward - don't ever allow this function to be inlined.

Here's a disassembly to confirm the bad inline:

c02aecf1 <test_wp_bit>:
c02aecf1:       55                      push   %ebp
c02aecf2:       89 e5                   mov    %esp,%ebp
c02aecf4:       83 ec 0c                sub    $0xc,%esp
c02aecf7:       c7 04 24 0c a0 25 c0    movl   $0xc025a00c,(%esp)
c02aecfe:       e8 63 73 e6 ff          call   c0116066 <printk>
c02aed03:       c7 44 24 08 25 00 00    movl   $0x25,0x8(%esp)
c02aed0a:       00 
c02aed0b:       c7 44 24 04 00 10 10    movl   $0x101000,0x4(%esp)
c02aed12:       00 
c02aed13:       c7 04 24 12 00 00 00    movl   $0x12,(%esp)
c02aed1a:       e8 d5 11 e6 ff          call   c010fef4 <__set_fixmap>
c02aed1f:       b8 01 00 00 00          mov    $0x1,%eax
c02aed24:       8a 15 00 d0 fe ff       mov    0xfffed000,%dl
c02aed2a:       88 15 00 d0 fe ff       mov    %dl,0xfffed000

Cheers,

Zachary Amsden (zach@vmware.com)