yesterday I tried to reactivate my old 486 box and wanted to install a
current Linux with latest kernel on it. But it turned out that the
latest kernel does not boot because the machine crashes early in the
setup code.
After some debugging it turned out that the problem is the query_ist()
function. If this interrupt with that function is called the machine
simply locks up. It looks like a BIOS bug. Looking for a workaround for
this problem I wrote the attached patch. It checks for the CPUID
instruction and if it is not implemented it does not call the speedstep
BIOS function. As far as I know speedstep should be available since some
Pentium earliest.
Alan Cox observed that it's available since the Pentium II, so cpuid
levels 4 and 5 can be excluded altogether.
H. Peter Anvin cleaned up the code some more:
> Right in concept, but I dislike the implementation (duplication of the
> CPU detect code we already have). Could you try this patch and see if
> it works for you?
which, with a small modification to fix a build error with it the
resulting kernel boots on my machine.
Signed-off-by: Joerg Roedel <joro@8bytes.org>
Signed-off-by: "H. Peter Anvin" <hpa@zytor.com>
Cc: <stable@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Remove old comments that include the old arch/i386 directory.
Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Move wakeup code to .c, so that video mode setting code can be shared
between boot and wakeup. Remove nasty assembly code in 64-bit case by
re-using trampoline code. Stack setup was fixed to clear high 16bits
of %esp, maybe that fixes some machines.
.c code sharing and morse code was done H. Peter Anvin, Sam Ravnborg
reviewed kbuild related stuff, and it seems okay to him. Rafael did
some cleanups.
[rjw:
* Made the patch stop breaking compilation on x86-32
* Added arch/x86/kernel/acpi/sleep.h
* Got rid of compiler warnings in arch/x86/kernel/acpi/sleep.c
* Fixed 32-bit compilation on x86-64 systems
* Added include/asm-x86/trampoline.h and fixed the non-SMP
compilation on 64-bit x86
* Removed arch/x86/kernel/acpi/sleep_32.c which was not used
* Fixed some breakage caused by the integration of smpboot.c done
under us in the meantime]
Signed-off-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Add prototype for cmdline_find_option_bool() missing from:
x86 setup: early cmdline parser handle boolean options
Also, fix up a minor formatting error in that patch.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Fix the operand constraints for the segment accessor functions,
{rd,wr}{fs,gs}*. In particular, the 8-bit functions used "r"
constraints instead of "q" constraints.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
We use signed values for limit checking since the values can go
negative under certain circumstances. However, sizeof() is unsigned
and forces the comparison to be unsigned, so move the comparison into
the heap_free() macros so we can ensure it is a signed comparison.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Apparently some specific versions of LILO enter the kernel with a
stack pointer that doesn't match the rest of the segments. Make our
best attempt at untangling the resulting mess.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Make <asm/setup.h> usable by the boot code.
Clean up vestiges of the old command-line protocol from setup.h and
head_32.S (it is still supported from the boot loader point of
view, since it is converted to the new command-line protocol by the
boot code.)
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>