Commit graph

26 commits

Author SHA1 Message Date
Rusty Russell
2a57ff1a70 [PATCH] i386: Rename cpu_gdt_descr and remove extern declaration from smpboot.c
When I implemented the DECLARE_PER_CPU(var) macros, I was careful that
people couldn't use "var" in a non-percpu context, by prepending
percpu__.  I never considered that this would allow them to overload
the same name for a per-cpu and a non-percpu variable.

It is only one of many horrors in the i386 boot code, but let's rename
the non-perpcu cpu_gdt_descr to early_gdt_descr (not boot_gdt_descr,
that's something else...)

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andi Kleen <ak@suse.de>

===================================================================
2007-02-13 13:26:26 +01:00
Rusty Russell
992af68147 [PATCH] i386: paravirt unhandled fallthrough
The current code simply calls "start_kernel" directly if we're under a
hypervisor and no paravirt_ops backend wants us, because paravirt.c
registers that as a backend.

This was always a vain hope; start_kernel won't get far without setup.
It's also impossible for paravirt_ops backends which don't sit in the
arch/i386/kernel directory: they can't link before paravirt.o anyway.

Keep it simple: if we pass all the registered paravirt probes, BUG().

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andi Kleen <ak@suse.de>
2007-02-13 13:26:26 +01:00
Vivek Goyal
f8657e1b55 [PATCH] i386: move startup_32() in text.head section
o Entry startup_32 was in .text section but it was accessing some init
  data too and it prompts MODPOST to generate compilation warnings.

WARNING: vmlinux - Section mismatch: reference to .init.data:boot_params from
.text between '_text' (at offset 0xc0100029) and 'startup_32_smp'
WARNING: vmlinux - Section mismatch: reference to .init.data:boot_params from
.text between '_text' (at offset 0xc0100037) and 'startup_32_smp'
WARNING: vmlinux - Section mismatch: reference to
.init.data:init_pg_tables_end from .text between '_text' (at offset
0xc0100099) and 'startup_32_smp'

o Can't move startup_32 to .init.text as this entry point has to be at the
  start of bzImage. Hence moved startup_32 to a new section .text.head and
  instructed MODPOST to not to generate warnings if init data is being
  accessed from .text.head section. This code has been audited.

o SMP boot up code (startup_32_smp) can go into .init.text if CPU hotplug
  is not supported. Otherwise it generates more warnings

WARNING: vmlinux - Section mismatch: reference to .init.data:new_cpu_data from
.text between 'checkCPUtype' (at offset 0xc0100126) and 'is486'
WARNING: vmlinux - Section mismatch: reference to .init.data:new_cpu_data from
.text between 'checkCPUtype' (at offset 0xc0100130) and 'is486'

Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Andi Kleen <ak@suse.de>
2007-02-13 13:26:22 +01:00
Zachary Amsden
7ce0bcfd16 [PATCH] i386: vMI backend for paravirt-ops
Fairly straightforward implementation of VMI backend for paravirt-ops.

[Adrian Bunk: some cleanups]

Signed-off-by: Zachary Amsden <zach@vmware.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Andi Kleen <ak@suse.de>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
2007-02-13 13:26:21 +01:00
Jeremy Fitzhardinge
464d1a78fb [PATCH] i386: Convert i386 PDA code to use %fs
Convert the PDA code to use %fs rather than %gs as the segment for
per-processor data.  This is because some processors show a small but
measurable performance gain for reloading a NULL segment selector (as %fs
generally is in user-space) versus a non-NULL one (as %gs generally is).

On modern processors the difference is very small, perhaps undetectable.
Some old AMD "K6 3D+" processors are noticably slower when %fs is used
rather than %gs; I have no idea why this might be, but I think they're
sufficiently rare that it doesn't matter much.

This patch also fixes the math emulator, which had not been adjusted to
match the changed struct pt_regs.

[frederik.deweerdt@gmail.com: fixit with gdb]
[mingo@elte.hu: Fix KVM too]

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Ian Campbell <Ian.Campbell@XenSource.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Zachary Amsden <zach@vmware.com>
Cc: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Frederik Deweerdt <frederik.deweerdt@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
2007-02-13 13:26:20 +01:00
Alon Bar-Lev
4e498b6610 [PATCH] Dynamic kernel command-line: i386
1. Rename saved_command_line into boot_command_line.
2. Set command_line as __initdata.

Signed-off-by: Alon Bar-Lev <alon.barlev@gmail.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-12 09:48:38 -08:00
Rusty Russell
c9ccf30d77 [PATCH] paravirt: Add startup infrastructure for paravirtualization
1) Each hypervisor writes a probe function to detect whether we are
   running under that hypervisor.  paravirt_probe() registers this
   function.

2) If vmlinux is booted with ring != 0, we call all the probe
   functions (with registers except %esp intact) in link order: the
   winner will not return.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Zachary Amsden <zach@vmware.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
2006-12-07 02:14:08 +01:00
Jeremy Fitzhardinge
f95d47caae [PATCH] i386: Use %gs as the PDA base-segment in the kernel
This patch is the meat of the PDA change.  This patch makes several related
changes:

1: Most significantly, %gs is now used in the kernel.  This means that on
   entry, the old value of %gs is saved away, and it is reloaded with
   __KERNEL_PDA.

2: entry.S constructs the stack in the shape of struct pt_regs, and this
   is passed around the kernel so that the process's saved register
   state can be accessed.

   Unfortunately struct pt_regs doesn't currently have space for %gs
   (or %fs). This patch extends pt_regs to add space for gs (no space
   is allocated for %fs, since it won't be used, and it would just
   complicate the code in entry.S to work around the space).

3: Because %gs is now saved on the stack like %ds, %es and the integer
   registers, there are a number of places where it no longer needs to
   be handled specially; namely context switch, and saving/restoring the
   register state in a signal context.

4: And since kernel threads run in kernel space and call normal kernel
   code, they need to be created with their %gs == __KERNEL_PDA.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Chuck Ebbert <76306.1226@compuserve.com>
Cc: Zachary Amsden <zach@vmware.com>
Cc: Jan Beulich <jbeulich@novell.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
2006-12-07 02:14:02 +01:00
Jeremy Fitzhardinge
9ca36101a8 [PATCH] i386: Basic definitions for i386-pda
This patch has the basic definitions of struct i386_pda, and the segment
selector in the GDT.

asm-i386/pda.h is more or less a direct copy of asm-x86_64/pda.h.  The most
interesting difference is the use of _proxy_pda, which is used to give gcc a
model for the actual memory operations on the real pda structure.  No actual
reference is ever made to _proxy_pda, so it is never defined.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Chuck Ebbert <76306.1226@compuserve.com>
Cc: Zachary Amsden <zach@vmware.com>
Cc: Jan Beulich <jbeulich@novell.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
2006-12-07 02:14:02 +01:00
Stas Sergeev
be44d2aabc [PATCH] i386: espfix cleanup
Clean up the espfix code:

- Introduced PER_CPU() macro to be used from asm
- Introduced GET_DESC_BASE() macro to be used from asm
- Rewrote the fixup code in asm, as calling a C code with the altered %ss
  appeared to be unsafe
- No longer altering the stack from a .fixup section
- 16bit per-cpu stack is no longer used, instead the stack segment base
  is patched the way so that the high word of the kernel and user %esp
  are the same.
- Added the limit-patching for the espfix segment. (Chuck Ebbert)

[jeremy@goop.org: use the x86 scaling addressing mode rather than shifting]
Signed-off-by: Stas Sergeev <stsp@aknet.ru>
Signed-off-by: Andi Kleen <ak@suse.de>
Acked-by: Zachary Amsden <zach@vmware.com>
Acked-by: Chuck Ebbert <76306.1226@compuserve.com>
Acked-by: Jan Beulich <jbeulich@novell.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
2006-12-07 02:14:01 +01:00
Jeremy Fitzhardinge
26fd5e084e [PATCH] i386: Fix fake return address
The fake return address was being set to __KERNEL_PDA, rather than 0.
Push it earlier while %eax still equals 0.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Andi Kleen <ak@muc.de>
Cc: Andrew Morton <akpm@osdl.org>
2006-10-21 18:37:02 +02:00
Chuck Ebbert
ec5c09269b [PATCH] i386: Do better early exception handlers
Add early i386 fault handlers with debug information for common faults.
Handles:

        divide error
        invalid opcode
        protection fault
        page fault

Also adds code to detect early recursive/multiple faults and halt the
system when they happen (taken from x86_64.)

Signed-off-by: Chuck Ebbert <76306.1226@compuserve.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Andi Kleen <ak@muc.de>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
2006-09-26 10:52:39 +02:00
Andi Kleen
29fe5f3baf [PATCH] i386: Add kernel thread stack frame termination for properly stopping stack unwinds.
One open question: Should this added push perhaps be made conditional
upon CONFIG_STACK_UNWIND or CONFIG_UNWIND_INFO?
[AK: not needed, these are all very slow paths]

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-08-30 16:05:15 -07:00
Jörn Engel
6ab3d5624e Remove obsolete #include <linux/config.h>
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-06-30 19:25:36 +02:00
Jan Beulich
4ef0652a74 [PATCH] i386: cleanup after cpu_gdt_descr conversion to per-cpu data
With cpu_gdt_descr having been converted to per-CPU data, the old object
(in head.S) no longer needs to reserve space for each CPU's instance.  With
cpu_gdt_table not being used for CPU 0 anymore, it doesn't seem to need
page alignment (or if in fact there is a need for it to retain that
alignment, the whole object should go into .data.page_align).

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Acked-by: Zachary Amsden <zach@vmware.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-23 07:38:06 -08:00
James Bottomley
2b932f6cf0 [PATCH] x86: fix broken SMP boot sequence
Recent GDT changes broke the SMP boot sequence if the booting CPU is
numbered anything other than zero.  There's also a subtle source of error
in that the boot time CPU now uses cpu_gdt_table (which is actually the GDT
for booting CPUs in head.S).  This patch fixes both problems by making GDT
descriptors themselves allocated from a per_cpu area and switching to them
in cpu_init(), which now means that cpu_gdt_table is exclusively used for
booting CPUs again.

Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
Cc: Zachary Amsden <zach@vmware.com>
Cc: Matt Tolentino <metolent@snoqualmie.dp.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-24 14:31:38 -08:00
Ingo Molnar
c0cdf1935c [PATCH] x86: print out early faults via early_printk()
Lost a few hours debugging an early-bootup fault within printk itself,
which manifested itself as a hard to debug early hang.

This patch makes it much easier by printing out early faults via
early_printk(), which function is a lot simpler than a full printk, and
hence more likely to succeed in emergencies.  (We do not recover from early
faults anyway, so there's no loss from not having these messages in the
normal printk buffer.)

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-11 21:41:11 -08:00
Zachary Amsden
e6a9918c96 [PATCH] x86: Fixed pnp bios limits
PnP BIOS data, code, and 32-bit entry segments all have fixed limits as well;
set them in the GDT rather than adding more code.  It would be nice to add
these fixups to the boot GDT rather than setting the GDT for each CPU; perhaps
I can wiggle this in later, but getting it in before the subsys init looks
tricky.

Also, make some progress on deprecating the ugly Q_SET_SEL macros.

Signed-off-by: Zachary Amsden <zach@vmware.com>
Cc: "Seth, Rohit" <rohit.seth@intel.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:35 -08:00
Zachary Amsden
5fe9fe3c6f [PATCH] x86: Pnp byte granularity
The one remaining caller of set_limit, the PnP BIOS code, calls into the PnP
BIOS, passing kernel parameters in and out.  These parameteres may be passed
from arbitrary kernel virtual memory, so they deserve strict protection to
stop a bad BIOS from smashing beyond the object size.

Unfortunately, the use of set_limit was badly botching this by setting the
limit in terms of pages, when it really should have byte granularity.

When doing this, I discovered my BIOS had the buggy code during the "get
system device node" call:

 mov ax, es:[bx]

Which is harmless, but has a trivial workaround.

Signed-off-by: Zachary Amsden <zach@vmware.com>
Cc: "Seth, Rohit" <rohit.seth@intel.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:35 -08:00
Zachary Amsden
99022c4695 [PATCH] x86: Apm seg in gdt
Since APM BIOS segment limits are now fixed, set them in head.S GDT and don't
use the complicated _set_limit() macro expansion.

Signed-off-by: Zachary Amsden <zach@vmware.com>
Acked-by: "Seth, Rohit" <rohit.seth@intel.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:35 -08:00
Zachary Amsden
7c4cb60e5b [PATCH] x86: GDT alignment fix
Make GDT page aligned and page padded to support running inside of a
hypervisor.  This prevents false sharing of the GDT page with other hot
data, which is not allowed in Xen, and causes performance problems in
VMware.

Rather than go back to the old method of statically allocating the GDT
(which wastes unneded space for non-present CPUs), the GDT for APs is
allocated dynamically.

Signed-off-by: Zachary Amsden <zach@vmware.com>
Cc: "Seth, Rohit" <rohit.seth@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:33 -08:00
Sam Ravnborg
86feeaa812 kbuild: full dependency check on asm-offsets.h
Building asm-offsets.h has been moved to a seperate Kbuild file
located in the top-level directory. This allow us to share the
functionality across the architectures.

The old rules in architecture specific Makefiles will die
in subsequent patches.

Furhtermore the usual kbuild dependency tracking is now used
when deciding to rebuild asm-offsets.s. So we no longer risk
to fail a rebuild caused by asm-offsets.c dependencies being touched.

With this common rule-set we now force the same name across
all architectures. Following patches will fix the rest.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2005-09-09 19:28:28 +02:00
Vivek Goyal
484b90c4b9 [PATCH] kdump: Save parameter segment in protected mode (x86)
o With introduction of kexec as boot-loader, the assumption that parameter
  segment will always be loaded at lower address than kernel and will be
  addressable by early bootup page tables is no longer valid. In kexec on
  panic case parameter segment might well be loaded beyond kernel image and
  might not be addressable by early boot page tables.
o This case might hit in the scenario where user has reserved a chunk of
  memory for second kernel, for example 16MB to 64MB, and has also built
  second kernel for physical memory location 16MB. In this case kexec has no
  choice but to load the parameter segment at a higher address than new kernel
  image at safe location where new kernel does not stomp it.
o Though problem should automatically go away once relocatable kernel for i386
  is in place and kexec can determine the location of new kernel at run time
  and load parameter segment at lower address than kernel image. But till then
  this patch can go in (assuming it does not break something else).
o This patch moves up the boot parameter saving code. Now boot parameters
  are copied out in protected mode before page tables are initialized. This
  will ensure that parameter segment is always addressable irrespective of
  its physical location.

Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:06:09 -07:00
Shaohua Li
d92de65cab [PATCH] variable overflow after hundreds round of hotplug CPU
I'm doing the cpu hotplug stress test and found a variable ('ready') is
overflow after several hundreds rounds of cpu hotplug.  Here is a fix.

Signed-off-by: Shaohua Li<shaohua.li@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-25 16:24:28 -07:00
Matt Mackall
d59745ce3e [PATCH] clean up kernel messages
Arrange for all kernel printks to be no-ops.  Only available if
CONFIG_EMBEDDED.

This patch saves about 375k on my laptop config and nearly 100k on minimal
configs.

Signed-off-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-01 08:59:02 -07:00
Linus Torvalds
1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00