Re: Kernel Bug in 2.4.35 when compiled gcc>=4.2.0 and -march=c3
From: Willy Tarreau
Date: Sun Aug 05 2007 - 15:19:36 EST
On Sun, Aug 05, 2007 at 05:43:37PM +0200, Willy Tarreau wrote:
> On Sun, Aug 05, 2007 at 10:56:04AM +0200, Axel Reinhold wrote:
> > i found a bug in linux-2.4.35.
> >
> > the bug produces a crashing kernel when compiled
> > with gcc >=4.2.0 and VIA C3 optimized -march=c3
> > (CONFIG_MCYRIXIII=y)
> >
> > this issue was first discussed on the gcc bugzilla:
> > http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32264
> >
> > and tracked down to the include/asm-i386/hw_irq.h
> > module with the help of the gcc guys:
> >
> > (pluto at agmk dot net) wrote:
> > >yup, i see something new :)
> > >
> > >please look at line 12137 of i8259.i:
> > >
> > >__attribute__((regparm(0))) void call_do_IRQ(void); __asm__(...
> > >
> > >as you can see there is a semicolon after call_do_IRQ(void)
> > >and following asm statement isn't treated as a function body.
> > >in this way -O1 -f{no-}unit-at-a-time accidentally produces
> > >different code. it's not a gcc bug.
> > >
> > >linux-2.4.35/include/asm-i386/hw_irq.h
> > >contains these evil macros.
> >
> > is there a chance to fix this?
> > these macros a far beyond my capabilities to fix.
>
> Axel,
>
> I've reproduced it and posted the following explanation to GCC's
> bugzilla ; I think I can provide you with a simple fix very soon.
OK Axel,
I have a fix now. Three good news :
- there were other symbols which were affected by -fno-unit-at-a-time under
gcc-4.2
- gcc-4.1 was also slightly affected but it was not very serious, since the
difference only lie in data <-> rodata
- vmlinux is smaller by 65 kB on my machine with both gcc-4.1 and gcc-4.2,
and bzImage is smaller by 7 kB. gcc-4.2's bzImage was 2.5 kB larger and
is now 100 bytes smaller.
The fix simply consists in removing -fno-unit-at-a-time with gcc-4, as is
done in 2.6. This was added for gcc-3.4 and is not appropriate for 4.x.
Here's the list of the other affected symbols. First column is the type of
the symbol and second one is the symbol name. It's a diff -y of the symbols
between vmlinux build with both gcc versions :
2.4.35 + gcc-4.2.1 | 2.4.35-git + gcc-4.2.1
d IRQ0x00_interrupt | t IRQ0x00_interrupt
d IRQ0x01_interrupt | t IRQ0x01_interrupt
d IRQ0x02_interrupt | t IRQ0x02_interrupt
d IRQ0x03_interrupt | t IRQ0x03_interrupt
d IRQ0x04_interrupt | t IRQ0x04_interrupt
d IRQ0x05_interrupt | t IRQ0x05_interrupt
d IRQ0x06_interrupt | t IRQ0x06_interrupt
d IRQ0x07_interrupt | t IRQ0x07_interrupt
d IRQ0x08_interrupt | t IRQ0x08_interrupt
d IRQ0x09_interrupt | t IRQ0x09_interrupt
d IRQ0x0a_interrupt | t IRQ0x0a_interrupt
d IRQ0x0b_interrupt | t IRQ0x0b_interrupt
d IRQ0x0c_interrupt | t IRQ0x0c_interrupt
d IRQ0x0d_interrupt | t IRQ0x0d_interrupt
d IRQ0x0e_interrupt | t IRQ0x0e_interrupt
d IRQ0x0f_interrupt | t IRQ0x0f_interrupt
d IRQ0x10_interrupt | t IRQ0x10_interrupt
d IRQ0x11_interrupt | t IRQ0x11_interrupt
d IRQ0x12_interrupt | t IRQ0x12_interrupt
d IRQ0x13_interrupt | t IRQ0x13_interrupt
d IRQ0x14_interrupt | t IRQ0x14_interrupt
d IRQ0x15_interrupt | t IRQ0x15_interrupt
d IRQ0x16_interrupt | t IRQ0x16_interrupt
d IRQ0x17_interrupt | t IRQ0x17_interrupt
d IRQ0x18_interrupt | t IRQ0x18_interrupt
d IRQ0x19_interrupt | t IRQ0x19_interrupt
d IRQ0x1a_interrupt | t IRQ0x1a_interrupt
d IRQ0x1b_interrupt | t IRQ0x1b_interrupt
d IRQ0x1c_interrupt | t IRQ0x1c_interrupt
d IRQ0x1d_interrupt | t IRQ0x1d_interrupt
d IRQ0x1e_interrupt | t IRQ0x1e_interrupt
d IRQ0x1f_interrupt | t IRQ0x1f_interrupt
d IRQ0x20_interrupt | t IRQ0x20_interrupt
d IRQ0x21_interrupt | t IRQ0x21_interrupt
d IRQ0x22_interrupt | t IRQ0x22_interrupt
d IRQ0x23_interrupt | t IRQ0x23_interrupt
d IRQ0x24_interrupt | t IRQ0x24_interrupt
d IRQ0x25_interrupt | t IRQ0x25_interrupt
d IRQ0x26_interrupt | t IRQ0x26_interrupt
d IRQ0x27_interrupt | t IRQ0x27_interrupt
d IRQ0x28_interrupt | t IRQ0x28_interrupt
d IRQ0x29_interrupt | t IRQ0x29_interrupt
d IRQ0x2a_interrupt | t IRQ0x2a_interrupt
d IRQ0x2b_interrupt | t IRQ0x2b_interrupt
d IRQ0x2c_interrupt | t IRQ0x2c_interrupt
d IRQ0x2d_interrupt | t IRQ0x2d_interrupt
d IRQ0x2e_interrupt | t IRQ0x2e_interrupt
d IRQ0x2f_interrupt | t IRQ0x2f_interrupt
d IRQ0x30_interrupt | t IRQ0x30_interrupt
d IRQ0x31_interrupt | t IRQ0x31_interrupt
d IRQ0x32_interrupt | t IRQ0x32_interrupt
d IRQ0x33_interrupt | t IRQ0x33_interrupt
d IRQ0x34_interrupt | t IRQ0x34_interrupt
d IRQ0x35_interrupt | t IRQ0x35_interrupt
d IRQ0x36_interrupt | t IRQ0x36_interrupt
d IRQ0x37_interrupt | t IRQ0x37_interrupt
d IRQ0x38_interrupt | t IRQ0x38_interrupt
d IRQ0x39_interrupt | t IRQ0x39_interrupt
d IRQ0x3a_interrupt | t IRQ0x3a_interrupt
d IRQ0x3b_interrupt | t IRQ0x3b_interrupt
d IRQ0x3c_interrupt | t IRQ0x3c_interrupt
d IRQ0x3d_interrupt | t IRQ0x3d_interrupt
d IRQ0x3e_interrupt | t IRQ0x3e_interrupt
d IRQ0x3f_interrupt | t IRQ0x3f_interrupt
d IRQ0x40_interrupt | t IRQ0x40_interrupt
d IRQ0x41_interrupt | t IRQ0x41_interrupt
d IRQ0x42_interrupt | t IRQ0x42_interrupt
d IRQ0x43_interrupt | t IRQ0x43_interrupt
d IRQ0x44_interrupt | t IRQ0x44_interrupt
d IRQ0x45_interrupt | t IRQ0x45_interrupt
d IRQ0x46_interrupt | t IRQ0x46_interrupt
d IRQ0x47_interrupt | t IRQ0x47_interrupt
d IRQ0x48_interrupt | t IRQ0x48_interrupt
d IRQ0x49_interrupt | t IRQ0x49_interrupt
d IRQ0x4a_interrupt | t IRQ0x4a_interrupt
d IRQ0x4b_interrupt | t IRQ0x4b_interrupt
d IRQ0x4c_interrupt | t IRQ0x4c_interrupt
d IRQ0x4d_interrupt | t IRQ0x4d_interrupt
d IRQ0x4e_interrupt | t IRQ0x4e_interrupt
d IRQ0x4f_interrupt | t IRQ0x4f_interrupt
d IRQ0x50_interrupt | t IRQ0x50_interrupt
d IRQ0x51_interrupt | t IRQ0x51_interrupt
d IRQ0x52_interrupt | t IRQ0x52_interrupt
d IRQ0x53_interrupt | t IRQ0x53_interrupt
d IRQ0x54_interrupt | t IRQ0x54_interrupt
d IRQ0x55_interrupt | t IRQ0x55_interrupt
d IRQ0x56_interrupt | t IRQ0x56_interrupt
d IRQ0x57_interrupt | t IRQ0x57_interrupt
d IRQ0x58_interrupt | t IRQ0x58_interrupt
d IRQ0x59_interrupt | t IRQ0x59_interrupt
d IRQ0x5a_interrupt | t IRQ0x5a_interrupt
d IRQ0x5b_interrupt | t IRQ0x5b_interrupt
d IRQ0x5c_interrupt | t IRQ0x5c_interrupt
d IRQ0x5d_interrupt | t IRQ0x5d_interrupt
d IRQ0x5e_interrupt | t IRQ0x5e_interrupt
d IRQ0x5f_interrupt | t IRQ0x5f_interrupt
d IRQ0x60_interrupt | t IRQ0x60_interrupt
d IRQ0x61_interrupt | t IRQ0x61_interrupt
d IRQ0x62_interrupt | t IRQ0x62_interrupt
d IRQ0x63_interrupt | t IRQ0x63_interrupt
d IRQ0x64_interrupt | t IRQ0x64_interrupt
d IRQ0x65_interrupt | t IRQ0x65_interrupt
d IRQ0x66_interrupt | t IRQ0x66_interrupt
d IRQ0x67_interrupt | t IRQ0x67_interrupt
d IRQ0x68_interrupt | t IRQ0x68_interrupt
d IRQ0x69_interrupt | t IRQ0x69_interrupt
d IRQ0x6a_interrupt | t IRQ0x6a_interrupt
d IRQ0x6b_interrupt | t IRQ0x6b_interrupt
d IRQ0x6c_interrupt | t IRQ0x6c_interrupt
d IRQ0x6d_interrupt | t IRQ0x6d_interrupt
d IRQ0x6e_interrupt | t IRQ0x6e_interrupt
d IRQ0x6f_interrupt | t IRQ0x6f_interrupt
d IRQ0x70_interrupt | t IRQ0x70_interrupt
d IRQ0x71_interrupt | t IRQ0x71_interrupt
d IRQ0x72_interrupt | t IRQ0x72_interrupt
d IRQ0x73_interrupt | t IRQ0x73_interrupt
d IRQ0x74_interrupt | t IRQ0x74_interrupt
d IRQ0x75_interrupt | t IRQ0x75_interrupt
d IRQ0x76_interrupt | t IRQ0x76_interrupt
d IRQ0x77_interrupt | t IRQ0x77_interrupt
d IRQ0x78_interrupt | t IRQ0x78_interrupt
d IRQ0x79_interrupt | t IRQ0x79_interrupt
d IRQ0x7a_interrupt | t IRQ0x7a_interrupt
d IRQ0x7b_interrupt | t IRQ0x7b_interrupt
d IRQ0x7c_interrupt | t IRQ0x7c_interrupt
d IRQ0x7d_interrupt | t IRQ0x7d_interrupt
d IRQ0x7e_interrupt | t IRQ0x7e_interrupt
d IRQ0x7f_interrupt | t IRQ0x7f_interrupt
d IRQ0x80_interrupt | t IRQ0x80_interrupt
d IRQ0x81_interrupt | t IRQ0x81_interrupt
d IRQ0x82_interrupt | t IRQ0x82_interrupt
d IRQ0x83_interrupt | t IRQ0x83_interrupt
d IRQ0x84_interrupt | t IRQ0x84_interrupt
d IRQ0x85_interrupt | t IRQ0x85_interrupt
d IRQ0x86_interrupt | t IRQ0x86_interrupt
d IRQ0x87_interrupt | t IRQ0x87_interrupt
d IRQ0x88_interrupt | t IRQ0x88_interrupt
d IRQ0x89_interrupt | t IRQ0x89_interrupt
d IRQ0x8a_interrupt | t IRQ0x8a_interrupt
d IRQ0x8b_interrupt | t IRQ0x8b_interrupt
d IRQ0x8c_interrupt | t IRQ0x8c_interrupt
d IRQ0x8d_interrupt | t IRQ0x8d_interrupt
d IRQ0x8e_interrupt | t IRQ0x8e_interrupt
d IRQ0x8f_interrupt | t IRQ0x8f_interrupt
d IRQ0x90_interrupt | t IRQ0x90_interrupt
d IRQ0x91_interrupt | t IRQ0x91_interrupt
d IRQ0x92_interrupt | t IRQ0x92_interrupt
d IRQ0x93_interrupt | t IRQ0x93_interrupt
d IRQ0x94_interrupt | t IRQ0x94_interrupt
d IRQ0x95_interrupt | t IRQ0x95_interrupt
d IRQ0x96_interrupt | t IRQ0x96_interrupt
d IRQ0x97_interrupt | t IRQ0x97_interrupt
d IRQ0x98_interrupt | t IRQ0x98_interrupt
d IRQ0x99_interrupt | t IRQ0x99_interrupt
d IRQ0x9a_interrupt | t IRQ0x9a_interrupt
d IRQ0x9b_interrupt | t IRQ0x9b_interrupt
d IRQ0x9c_interrupt | t IRQ0x9c_interrupt
d IRQ0x9d_interrupt | t IRQ0x9d_interrupt
d IRQ0x9e_interrupt | t IRQ0x9e_interrupt
d IRQ0x9f_interrupt | t IRQ0x9f_interrupt
d IRQ0xa0_interrupt | t IRQ0xa0_interrupt
d IRQ0xa1_interrupt | t IRQ0xa1_interrupt
d IRQ0xa2_interrupt | t IRQ0xa2_interrupt
d IRQ0xa3_interrupt | t IRQ0xa3_interrupt
d IRQ0xa4_interrupt | t IRQ0xa4_interrupt
d IRQ0xa5_interrupt | t IRQ0xa5_interrupt
d IRQ0xa6_interrupt | t IRQ0xa6_interrupt
d IRQ0xa7_interrupt | t IRQ0xa7_interrupt
d IRQ0xa8_interrupt | t IRQ0xa8_interrupt
d IRQ0xa9_interrupt | t IRQ0xa9_interrupt
d IRQ0xaa_interrupt | t IRQ0xaa_interrupt
d IRQ0xab_interrupt | t IRQ0xab_interrupt
d IRQ0xac_interrupt | t IRQ0xac_interrupt
d IRQ0xad_interrupt | t IRQ0xad_interrupt
d IRQ0xae_interrupt | t IRQ0xae_interrupt
d IRQ0xaf_interrupt | t IRQ0xaf_interrupt
d IRQ0xb0_interrupt | t IRQ0xb0_interrupt
d IRQ0xb1_interrupt | t IRQ0xb1_interrupt
d IRQ0xb2_interrupt | t IRQ0xb2_interrupt
d IRQ0xb3_interrupt | t IRQ0xb3_interrupt
d IRQ0xb4_interrupt | t IRQ0xb4_interrupt
d IRQ0xb5_interrupt | t IRQ0xb5_interrupt
d IRQ0xb6_interrupt | t IRQ0xb6_interrupt
d IRQ0xb7_interrupt | t IRQ0xb7_interrupt
d IRQ0xb8_interrupt | t IRQ0xb8_interrupt
d IRQ0xb9_interrupt | t IRQ0xb9_interrupt
d IRQ0xba_interrupt | t IRQ0xba_interrupt
d IRQ0xbb_interrupt | t IRQ0xbb_interrupt
d IRQ0xbc_interrupt | t IRQ0xbc_interrupt
d IRQ0xbd_interrupt | t IRQ0xbd_interrupt
d IRQ0xbe_interrupt | t IRQ0xbe_interrupt
d IRQ0xbf_interrupt | t IRQ0xbf_interrupt
d IRQ0xc0_interrupt | t IRQ0xc0_interrupt
d IRQ0xc1_interrupt | t IRQ0xc1_interrupt
d IRQ0xc2_interrupt | t IRQ0xc2_interrupt
d IRQ0xc3_interrupt | t IRQ0xc3_interrupt
d IRQ0xc4_interrupt | t IRQ0xc4_interrupt
d IRQ0xc5_interrupt | t IRQ0xc5_interrupt
d IRQ0xc6_interrupt | t IRQ0xc6_interrupt
d IRQ0xc7_interrupt | t IRQ0xc7_interrupt
d IRQ0xc8_interrupt | t IRQ0xc8_interrupt
d IRQ0xc9_interrupt | t IRQ0xc9_interrupt
d IRQ0xca_interrupt | t IRQ0xca_interrupt
d IRQ0xcb_interrupt | t IRQ0xcb_interrupt
d IRQ0xcc_interrupt | t IRQ0xcc_interrupt
d IRQ0xcd_interrupt | t IRQ0xcd_interrupt
d IRQ0xce_interrupt | t IRQ0xce_interrupt
d IRQ0xcf_interrupt | t IRQ0xcf_interrupt
d IRQ0xd0_interrupt | t IRQ0xd0_interrupt
d IRQ0xd1_interrupt | t IRQ0xd1_interrupt
d IRQ0xd2_interrupt | t IRQ0xd2_interrupt
d IRQ0xd3_interrupt | t IRQ0xd3_interrupt
d IRQ0xd4_interrupt | t IRQ0xd4_interrupt
d IRQ0xd5_interrupt | t IRQ0xd5_interrupt
d IRQ0xd6_interrupt | t IRQ0xd6_interrupt
d IRQ0xd7_interrupt | t IRQ0xd7_interrupt
d IRQ0xd8_interrupt | t IRQ0xd8_interrupt
d IRQ0xd9_interrupt | t IRQ0xd9_interrupt
d IRQ0xda_interrupt | t IRQ0xda_interrupt
d IRQ0xdb_interrupt | t IRQ0xdb_interrupt
d IRQ0xdc_interrupt | t IRQ0xdc_interrupt
d IRQ0xdd_interrupt | t IRQ0xdd_interrupt
d IRQ0xde_interrupt | t IRQ0xde_interrupt
d IRQ0xdf_interrupt | t IRQ0xdf_interrupt
d apic_timer_interrupt | t apic_timer_interrupt
d call_apic_timer_interrupt | t call_apic_timer_interrupt
d call_call_function_interrup | t call_call_function_interrup
d call_do_IRQ | t call_do_IRQ
d call_error_interrupt | t call_error_interrupt
d call_function_interrupt | t call_function_interrupt
d call_invalidate_interrupt | t call_invalidate_interrupt
d call_reschedule_interrupt | t call_reschedule_interrupt
d call_spurious_interrupt | t call_spurious_interrupt
d common_interrupt | t common_interrupt
d error_interrupt | t error_interrupt
d invalidate_interrupt | t invalidate_interrupt
d reschedule_interrupt | t reschedule_interrupt
I also noticed a few drivers which do not build with gcc-4.2 (eg: wdt83627).
I'll have to adress this later.
Anyway, could you please try the appended patch ? At least it works for me,
and I expect it to fix your problem too :
willy@pcw:~$ cat /proc/version
Linux version 2.4.35 (willy@pcw) (gcc version 4.2.1) #1 SMP Sun Aug 5 20:55:56 CEST 2007
Thanks,
Willy