Messages in this thread Patch in this message | | | Date | Thu, 1 Aug 2002 03:01:08 +0200 (MET DST) | From | Mikael Pettersson <> | Subject | Re: 2.5.29: bug in ide and hd kernel option handling |
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On Tue, 30 Jul 2002, I wrote: > On my 486 test box (ISA/VLB only, CONFIG_PCI=n), passing any > any ide or hd kernel option (like idebus=33) to 2.5.29 results > in a kernel hang at boot: I get the initial "Uncompressing .. > booting .." and then nothing.
Problem partially identified.
With CONFIG_PCI=n, include/asm-i386/ide.h:ide_init_default_hwifs() is defined to ide_register_hw() the PC's standard IDE ports, but with CONFIG_PCI=y, it's empty.
When drivers/ide/main.c:ide_setup() is called for some "ide..." kernel option, it starts by calling init_global_data(), which in turn calls ide_init_default_hwifs(). When CONFIG_PCI=n so ide_init_default_hwifs() isn't empty, the kernel either hangs or reboots at that point.
init_global_data() and ide_init_default_hwifs() can also be called much later from 'module_init(init_ata)'. In that case there is no hang or reboot -- so my guess is that the initialisation does something which normally works but is illegal and causes a fault when done at __setup()-time.
I tested every kernel from 2.5.29 and back, and the problem started with 2.5.5.
As a workaround I applied the patch below to unconditionally make ide_init_default_hwifs() do nothing. This solved my problem and doesn't seem to have had any bad side-effects: the kernel still finds all standard IDE ports on my 486.
/Mikael
--- linux-2.5.29/include/asm-i386/ide.h.~1~ Sat Jul 20 23:49:45 2002 +++ linux-2.5.29/include/asm-i386/ide.h Thu Aug 1 02:20:31 2002 @@ -65,7 +65,7 @@ static __inline__ void ide_init_default_hwifs(void) { -#ifndef CONFIG_PCI +#if 0 && !defined(CONFIG_PCI) hw_regs_t hw; int index; - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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