Current gcc generates calls not jumps to noreturn functions. When that happens the
return address can point to the next function, which confuses the unwinder.
This patch works around it by marking asynchronous exception
frames in contrast normal call frames in the unwind information. Then teach
the unwinder to decode this.
For normal call frames the unwinder now subtracts one from the address which avoids
this problem. The standard libgcc unwinder uses the same trick.
It doesn't include adjustment of the printed address (i.e. for the original
example, it'd still be kernel_math_error+0 that gets displayed, but the
unwinder wouldn't get confused anymore.
This only works with binutils 2.6.17+ and some versions of H.J.Lu's 2.6.16
unfortunately because earlier binutils don't support .cfi_signal_frame
[AK: added automatic detection of the new binutils and wrote description]
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andi Kleen <ak@suse.de>
We do some additional CPU synchronization in gettimeofday et.al. to make
sure the time stamps are always monotonic over multiple CPUs. But on
single core systems that is not needed. So don't do it.
Signed-off-by: Andi Kleen <ak@suse.de>
Got it. i8259A_resume calls init_8259A(0) unconditionally, even if
auto_eoi has been set. Keep track of the current status and restore that
on resume. This fixes it for AMD64 and i386.
Signed-off-by: Matthew Garrett <mjg59@srcf.ucam.org>
Signed-off-by: Andi Kleen <ak@suse.de>
Sometimes, bug reports come in where we've had an oops, and the
only record we have is what the reporter saw on screen shortly
before the system locked up completely. Unfortunatly, syslog
only prints lines beginning with KERN_EMERG to the console, so
some lines get lost.
An example of this can be seen at https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=203723
Some of this information isn't vital to diagnosis, but some parts
are useful, such as the tainted flag.
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Fix pack_descriptor:
1. flags are bits 20-23 in the high word
2. limit's 4 msb are bits 16-19 in the high word
These haven't mattered so far, because all users have had small limits
and a flags setting of 0.
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Andi Kleen <ak@suse.de>
===================================================================
On Sat, Sep 09, 2006 at 04:14:29PM +0200, Andi Kleen wrote:
> [patch] Looks reasonable, but probably not for 2.6.18 because this stuff
> is already too fragile and it is probably too risky to do any big changes now
> since not enough testing time is left. Can you please resubmit
> it with proper description and signed-off-by line? I can queue it for .19 then
>
> -Andi
Patch inserts PCI memory mapped config region(s) into the resource map. This
will allow for the MMCCONFIG regions to be marked as busy in the iomem
address space as well as the regions(s) showing up in /proc/iomem.
Signed-off-by: Aaron Durbin <adurbin@google.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Patch inserts the GART region into the iomem resource map. The GART will then
be visible within /proc/iomem. It will also allow for other users
utilizing the GART to subreserve the region (agp or IOMMU).
Signed-off-by: Aaron Durbin <adurbin@google.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Needs earlier patch to split type 1 probing from use.
This patch should fix the x86 macs where type 1 PCI config space access
doesn't work, but MCFG does. They also don't have a usable e820 table
so the e820 sanity check failed.
Instead assume now that if type 1 doesn't work then MCFG must work
and don't do the e820 check.
Signed-off-by: Andi Kleen <ak@suse.de>
First probe if type1/2 accesses work, but then only initialize them at the end.
This is useful for a later patch that needs this information inbetween.
Signed-off-by: Andi Kleen <ak@suse.de>
Previously exit_idle would be called more often than enter_idle
Now instead of using complicated tests just keep track of it
using the per CPU variable as a flip flop. I moved the idle state into the
PDA to make the access more efficient.
Original bug report and an initial patch from Stephane Eranian,
but redone by AK.
Cc: Stephane Eranian <eranian@hpl.hp.com>
Signed-off-by: Andi Kleen <ak@suse.de>
kexec has been marked experimental for a year now and all
of the serious problems have been worked through. So it
is time (if not past time) to remove the experimental mark.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andi Kleen <ak@suse.de>
kexec has been marked experimental for a year now and all
of the serious problems have been worked through. So it
is time (if not past time) to remove the experimental mark.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Before 2.6.16 this was changed to work around code that accessed
CPUs not in the possible map. But that code should be all fixed now,
so mark it __initdata again.
Signed-off-by: Andi Kleen <ak@suse.de>
Reindent the macros in x86-64 pda.h, making them much more readable.
Follows Jeremy's i386 version of this.
No functional changes
Signed-off-by: Andi Kleen <ak@suse.de>
Fix
linux/fs/compat.c: In function compat_sys_pselect7
linux/fs/compat.c:1869: warning: ignoring return value of copy_to_user, declared with attribute warn_unused_result
To make it easier to handle I changed to semantics to not try to
write out a timespec if an error occurred. I hope that's ok.
Cc: dwmw2@infradead.org
Signed-off-by: Andi Kleen <ak@suse.de>
- Don't zero for __copy_from_user_inatomic following i386.
This will prevent spurious zeros for parallel file system writers when
one does a exception
- The string instruction version didn't zero the output on
exception. Oops.
Also I cleaned up the code a bit while I was at it and added a minor
optimization to the string instruction path.
Signed-off-by: Andi Kleen <ak@suse.de>
Add HPET(s) into resource map. This will allow for the HPET(s) to be
visibile within /proc/iomem.
Signed-off-by: Aaron Durbin <adurbin@google.com>
Signed-off-by: Andi Kleen <ak@suse.de>
This patch places the IOAPIC(s) and the Local APIC specified by ACPI
tables into the resource map. The APICs will then be visible within
/proc/iomem
Signed-off-by: Aaron Durbin <adurbin@google.com>
Signed-off-by: Andi Kleen <ak@suse.de>
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>
We allow for the fact that the guest kernel may not run in ring 0. This
requires some abstraction in a few places when setting %cs or checking
privilege level (user vs kernel).
This is Chris' [RFC PATCH 15/33] move segment checks to subarch, except rather
than using #define USER_MODE_MASK which depends on a config option, we use
Zach's more flexible approach of assuming ring 3 == userspace. I also used
"get_kernel_rpl()" over "get_kernel_cs()" because I think it reads better in
the code...
1) Remove the hardcoded 3 and introduce #define SEGMENT_RPL_MASK 3 2) Add a
get_kernel_rpl() macro, and don't assume it's zero.
And:
Clean up of patch for letting kernel run other than ring 0:
a. Add some comments about the SEGMENT_IS_*_CODE() macros.
b. Add a USER_RPL macro. (Code was comparing a value to a mask
in some places and to the magic number 3 in other places.)
c. Add macros for table indicator field and use them.
d. Change the entry.S tests for LDT stack segment to use the macros
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Zachary Amsden <zach@vmware.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Andi Kleen <ak@suse.de>
Abstract sensitive instructions in assembler code, replacing them with macros
(which currently are #defined to the native versions). We use long names:
assembler is case-insensitive, so if something goes wrong and macros do not
expand, it would assemble anyway.
Resulting object files are exactly the same as before.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Andi Kleen <ak@suse.de>
Fix
linux/arch/x86_64/kernel/process.c: In function __switch_to:
linux/arch/x86_64/kernel/process.c:626: warning: assignment makes integer from pointer without a cast
Signed-off-by: Andi Kleen <ak@suse.de>
I just added type checking for assignments the PDA in the i386 PDA code.
Here's the x86-64 equivalent. (Obviously this doesn't contain the latest
x86-64 PDA change.)
Signed-off-by: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: Andi Kleen <ak@suse.de>
Add a feature check that checks that the gcc compiler has stack-protector
support and has the bugfix for PR28281 to make this work in kernel mode.
The easiest solution I could find was to have a shell script in scripts/
to do the detection; if needed we can make this fancier in the future
without making the makefile too complex.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andi Kleen <ak@suse.de>
CC: Andi Kleen <ak@suse.de>
CC: Sam Ravnborg <sam@ravnborg.org>
GCC emits a call to a __stack_chk_fail() function when the stack canary is
not matching the expected value.
Since this is a bad security issue; lets panic the kernel rather than limping
along; the kernel really can't be trusted anymore when this happens.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andi Kleen <ak@suse.de>
CC: Andi Kleen <ak@suse.de>
This patch adds the per thread cookie field to the task struct and the PDA.
Also it makes sure that the PDA value gets the new cookie value at context
switch, and that a new task gets a new cookie at task creation time.
Signed-off-by: Arjan van Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andi Kleen <ak@suse.de>
CC: Andi Kleen <ak@suse.de>
This patch adds the config options for -fstack-protector.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andi Kleen <ak@suse.de>
CC: Andi Kleen <ak@suse.de>
Change the comments in the pda structure to make the first fields to have
their offset documented and to have the comments aligned.
The stack protector series needs a field at offset 40 (gcc ABI); annotate
upto 40 for that reason.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andi Kleen <ak@suse.de>
CC: Andi Kleen <ak@suse.de>
Because it can take spinlocks.
Suggested by Mathieu Desnoyers
Cc: Mathieu Desnoyers <compudj@krystal.dyndns.org>
Signed-off-by: Andi Kleen <ak@suse.de>
kexec: Avoid overwriting the current pgd (V4, i386)
This patch upgrades the i386-specific kexec code to avoid overwriting the
current pgd. Overwriting the current pgd is bad when CONFIG_CRASH_DUMP is used
to start a secondary kernel that dumps the memory of the previous kernel.
The code introduces a new set of page tables. These tables are used to provide
an executable identity mapping without overwriting the current pgd.
Signed-off-by: Magnus Damm <magnus@valinux.co.jp>
Signed-off-by: Andi Kleen <ak@suse.de>
kexec: Avoid overwriting the current pgd (V4, x86_64)
This patch upgrades the x86_64-specific kexec code to avoid overwriting the
current pgd. Overwriting the current pgd is bad when CONFIG_CRASH_DUMP is used
to start a secondary kernel that dumps the memory of the previous kernel.
The code introduces a new set of page tables. These tables are used to provide
an executable identity mapping without overwriting the current pgd.
Signed-off-by: Magnus Damm <magnus@valinux.co.jp>
Signed-off-by: Andi Kleen <ak@suse.de>
Remove most of the special cases for the debug IST stack. This is a
follow on clean up patch, it requires the bug fix patch that adds
orig_ist.
Signed-off-by: Keith Owens <kaos@ocs.com.au>
Signed-off-by: Andi Kleen <ak@suse.de>
The EDD code would scan the command line as a fixed array, without
taking account of either whitespace, null-termination, the old
command-line protocol, late overrides early, or the fact that the
command line may not be reachable from INITSEG.
This should fix those problems, and enable us to use a longer command
line.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Based on a idea by Jeremy Fitzhardinge:
Replace the volatiles and memory clobbers in the PDA access with
telling gcc about access to a proxy PDA structure that doesn't
actually exist. But the dummy accesses give a defined ordering for
read/write accesses.
Also add some memory barriers to the early GS initialization to
make sure no PDA access is moved before it.
Advantage is some .text savings (probably most from better
code for accessing "current"):
text data bss dec hex filename
4845647 1223688 615864 6685199 66020f vmlinux
4837780 1223688 615864 6677332 65e354 vmlinux-pda
1.2% smaller code
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: Andi Kleen <ak@suse.de>
This patch updates x86_64 linker script to pack any .note.* sections
into a PT_NOTE segment in the output file.
To do this, we tell ld that we need a PT_NOTE segment. This requires
us to start explicitly mapping sections to segments, so we also need
to explicitly create PT_LOAD segments for text and data, and map the
sections to them appropriately. Fortunately, each section will
default to its previous section's segment, so it doesn't take many
changes to vmlinux.lds.S.
The corresponding change is already made for i386 in -mm and I'd like
this patch to join it. The section to segment mappings do change as do
the segment flags so some time in -mm would be good for that reason as
well, just in case.
In particular .data and .bss move from the text segment to the data
segment and .data.cacheline_aligned .data.read_mostly are put in the
data segment instead of a separate one.
I think that it would be possible to exactly match the existing section
to segment mapping and flags but it would be a more intrusive change and
I'm not sure there is a reason for the existing layout other than it is
what you get by default if you don't explicitly specify something else.
If there is a reason for the existing layout then I will of course make
the more intrusive change. If there is no reason we could probably drop
the executable or writable flags from some segments but I don't know how
much attention is paid to them anyway so it might not be worth the
effort.
The vsyscall related sections need to go in a different segment to the
normal data segment and so I invented a "user" segment to contain them.
I believe this should appear to be another data segment as far as the
kernel is concerned so the flags are setup accordingly.
The notes will be used in the Xen paravirt_ops backend to provide
additional information to the domain builder. I am in the process of
converting the xen-unstable kernels and tools over to this scheme at the
moment to support this in the future.
It has been suggested to me that the notes segment should have flags 0
(i.e. not readable) since it is only used by the loader and is not used
at runtime. For now I went with a readable segment since that is what
the i386 patch uses.
AK: dropped NOTES addition right now because the needed infrastructure
for that is not merged yet
Signed-off-by: Ian Campbell <ian.campbell@xensource.com>
Signed-off-by: Andi Kleen <ak@suse.de>
